A double Cardan universal joint is a near-constant velocity universal joint that may be used to correct deficiencies associated with a single Cardan universal joint. A typical double Cardan universal joint generally includes two single Cardan universal joints connected by a unitary coupling yoke having a centering mechanism. Thus, a typical double Cardan universal joint includes a first yoke connected to a first cross shaft, a coupling yoke having a first end connected to the first cross shaft and a second end connected to a second cross shaft, and a second yoke connected to the second cross shaft. The centering mechanism may include mating ball and socket portions provided on the first and second yokes. The coupling yoke cooperates with the centering mechanism to generally bisect an angle between the first and second yokes. As a result, near constant velocity operating characteristics may be attained during operation.
Referring now to the discussion that follows and also to the drawings, illustrative approaches to the disclosed systems and methods are shown in detail. Although the drawings represent some possible approaches, the drawings are not necessarily to scale and certain features may be exaggerated, removed, or partially sectioned to better illustrate and explain the present disclosure. Further, the descriptions set forth herein are not intended to be exhaustive, otherwise limit, or restrict the claims to the precise forms and configurations shown in the drawings and disclosed in the following detailed description.
With reference to
With continued to reference to
First universal joint 12 may include a first yoke 26 attached to an end of first shaft 14, and a second yoke 28 extending from an end of universal joint coupling yoke 20. A first cross shaft 30 interconnects first yoke 26 to second yoke 28. First yoke 26 is bifurcated and includes a pair of laterally spaced legs 32 arranged generally symmetrical with respect to rotary longitudinal axis 21 of first shaft 14. Only one of the two legs 32 is visible in
First cross shaft 30 includes a first pair of coaxially aligned trunions 40, and a second pair of coaxially aligned trunions 42. Trunions 40 and 42 extend radially outward from a hub 44 of first cross shaft 30. First trunions 40 are arranged substantially perpendicular to second trunions 42. Only one of the two first trunions 40 is visible in
First universal joint 12 also includes a first pair of bearing caps 46 mounted in apertures 34 of first yoke 26, and a second pair of bearing caps 48 mounted in apertures 38 of second yoke 28. First bearing caps 46 receive and rotatably support first trunions 40 in apertures 34. Similarly, second bearing caps 48 receive and rotatably support second trunions 42 in apertures 38. A roller bearing 50 is arranged between each first bearing cap 46 and first trunion 40, and between each second bearing cap 48 and second trunion 42. Roller bearing 50 associated with bearing cap 46 and first trunion 40 is not visible in
Second universal joint 16 may include a third yoke 52 attached to an end of second shaft 18 and a fourth yoke 54 extending from an end of universal joint coupling yoke 20. A second cross shaft 56 interconnects third yoke 52 to fourth yoke 54. Third yoke 52 is bifurcated and includes a pair of laterally spaced legs 58 arranged generally symmetrical with respect to rotary longitudinal axis 23 of second shaft 18. Only one of the two legs 58 is visible in
Second cross shaft 56 includes a first pair of coaxially aligned trunions 66 and a second pair of coaxially aligned trunions 68. Trunions 66 and 68 extend radially outward from a hub 70 of second cross shaft 56. First trunions 66 are arranged substantially perpendicular to second trunions 68. Only one of the two first trunions 66 is visible in
Second universal joint 16 also includes a first pair of bearing caps 72 mounted in apertures 60 of third yoke 52, and a second pair of bearing caps 74 mounted in apertures 64 of fourth yoke 54. First bearing caps 72 receive and rotatably support first trunions 66 in apertures 60. Similarly, second bearing caps 74 receive and rotatably support second trunions 68 in apertures 64. A roller bearing 75 is arranged between each first bearing cap 72 and first trunion 66, and between each second bearing cap 74 and second trunion 68. Roller bearing 75 associated with bearing cap 72 and first trunion 66 is not visible in
Referring also to
Centering mechanism 22 may also include a cylindrical stem 84 that extends from an end 86 of second shaft 18. A counterbore 88 may be formed in the cylindrical stem 84 for receiving a biasing member 90 therein. A spherical ball 92 having the ends thereof truncated includes a bore 91 for receiving cylindrical stem 84. Interposed between ball 92 and cylindrical stem 84 are a plurality of pins 94 for enabling ball 92 to slide and rotate relative to stem 84. A bearing assembly, such as a roller bearing, may be used in place of pins 94. A bushing 96 arranged within bore 91 engages a flange 98 of spherical ball 92.
Biasing member 90 is disposed within counterbore 88 formed in stem 84 of second shaft 18. Biasing member 90 may be a spring or similar biasing device providing a biasing force to direct ball 92 in a biasing direction “A”. In a non-displaced condition of constant velocity joint 10 (as shown in
When first universal joint 12 and second universal joint 16 rotate in response to a deflection load, centering mechanism 22 can displace in a centering displacement path represented by arrow “B”. In a non-displaced condition for constant velocity joint 10, first shaft 14 and second shaft 18 are both aligned coaxially along rotary longitudinal axis 24 of constant velocity joint 10.
Continuing to refer to
Bearing member 80 may also include a generally spherical-shaped region 106 arranged adjacent conical inside surface region 102. Spherical shaped region 106 may be sized larger than outer surface 100 of ball 92 to provide a gap 108 between outer surface 100 of ball 92 and spherical-shaped region 106 of bearing member 80. Gap 108 may be sized to maximize wicking of lubricant toward contact line 104 between ball 92 and bearing member 80.
Centering mechanism 22 may further include a first seal 110 secured within recessed pocket 76. First seal 110 operates to help prevent leakage of lubricant and prevent foreign matter from entering between ball 92 and bearing member 80. A second seal 112 positioned over cylindrical stem 84 engages bore 91 of spherical ball 92. Second seal 112 operates to help prevent leakage of lubricant and to prevent foreign matter from entering between cylindrical stem 84 and ball 92.
It will be appreciated that the exemplary constant velocity joint described herein has broad applications. The foregoing configuration were chosen and described in order to illustrate principles of the methods and apparatuses as well as some practical applications. The preceding description enables others skilled in the art to utilize methods and apparatuses in various configurations and with various modifications as are suited to the particular use contemplated. In accordance with the provisions of the patent statutes, the principles and modes of operation of the disclosed constant velocity joint have been explained and illustrated in exemplary configurations.
It is intended that the scope of the present methods and apparatuses be defined by the following claims. However, it must be understood that the disclosed exemplary constant velocity joint may be practiced otherwise than is specifically explained and illustrated without departing from its spirit or scope. It should be understood by those skilled in the art that various alternatives to the configuration described herein may be employed in practicing the claims without departing from the spirit and scope as defined in the following claims. The scope of the disclosed constant velocity joint should be determined, not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. It is anticipated and intended that future developments will occur in the arts discussed herein, and that the disclosed systems and methods will be incorporated into such future examples. Furthermore, all terms used in the claims are intended to be given their broadest reasonable constructions and their ordinary meanings as understood by those skilled in the art unless an explicit indication to the contrary is made herein. In particular, use of the singular articles such as “a,” “the,” “said,” etc. should be read to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary. It is intended that the following claims define the scope of the device and that the method and apparatus within the scope of these claims and their equivalents be covered thereby. In sum, it should be understood that the device is capable of modification and variation and is limited only by the following claims.