Common Terms
| Common Terms | Definition |
|---|---|
|
Bearing Plate |
A retainer plate fixed to the back of a round bearing used to position the bearing in the yoke. |
|
Balancing |
A procedure in which the distribution of mass in a rotating body is
checked and altered where necessary to ensure that vibration does not occur during operation. |
|
Ball Seat |
A full or segmented angular contact bearing located in a socket that supports and centers the ball stud. |
|
Ball Stud |
A yoke generally used in CV applications which incorporates a stud onto which a ball is mounted |
|
Brinnelling |
Failure that occurs when the static forces between two curved surfaces in contact result in local yielding of one or both mating members to produce permanent surface discontinuity. Example: Needle roller indents on a u-joint trunnion or trunnions |
|
Cardan Universal Joint |
A non-constant velocity universal joint consisting of two yokes connected by a cross through four bearings and driveable by external sources. |
|
Center Support |
A rolling bearing element surrounded by rubber, mounted in a bracket
configuration used to mount the support to an outside structure. |
|
Centering Socket Yoke |
A yoke assembly that functions as a self-aligning bearing and provides support and a means of centering in double cardan universal joints. |
|
Companion Flange |
A flanged member that attaches a driveline to drivetrain components,
typically affixed by some bolt-together method. |
|
Critical Speed |
The speed at which the rotational speed of a shaft coincides with the
natural vibration frequency of the shaft, causing a dynamically unstable condition. |
|
Cross and
Bearing Kit |
Drive member with four equally spaced trunnions in the same plane and four bearing cups with attaching parts. Also referred to as a universal joint kit or u-joint kit. |
|
Cross Hole |
A through hole located in each ear of a yoke used to locate a round
bearing. |
|
Double Cardan
Universal Joint |
A near constant velocity universal joint consisting of two trunnion type Cardan universal joints whose trunnion yokes are connected by a coupling yoke or H-yoke with internal supporting and centering means. |
|
Driveline |
An assembly of one or more driveshafts with provisions for axial
movement, which transmits torque and/or rotary motion. |
|
Driveshaft |
An assembly of one or two universal joints connected to a solid or tubular shaft member. |
|
Driveshaft Length
Center to Center |
The distance between the outermost universal joint centers on a
driveshaft. |
|
Drive Train |
Term used for the unit of all components from the Transmission to Rear differential. Also referred to as Power Train. |
|
Ear |
One of two projecting parts of a yoke symmetrically located with respect to the rotational axis. |
|
End Yoke |
A yoke which attaches a driveshaft to another drive train component such as the transmission. |
|
Flange Yoke |
The yoke which attaches the driveshaft assembly to a companion flange. |
|
Flinger |
A protective shield used in front of and behind the bearing and rubber on many center supports and end yokes. |
|
Galling |
Failure that occurs when two sliding surfaces are subjected to such a
combination of loads, sliding velocities, temperatures, environments, and lubricants, that massive surface destruction is caused by welding and tearing, plowing, and gouging. Example: Bearing cup/trunnion end galling on a cross and bearing kit. |
|
Glidecote |
The blue, nylon, wear-resistant coating on yoke shafts and tube shafts. |
|
H-Yoke |
A double yoke which connects the two halves of a double cardan universal joint. |
|
Half Round Yoke
Cross Hole |
A semicircular hole located on the end of each ear of some end yokes and used to locate a round bearing. |
|
Hub |
The central part of a yoke used for attachment to another member. |
|
Inside Lock-up |
Term referring to either a cross and bearing kit or a yoke that utilizes a snap ring seated in a groove in the bearing cups and located inside the yoke ears to retain the kit in the yoke. |
|
Joint Angle |
The angle described by the intersection of rotational axis of the input and output members of a universal joint and measured on the same plane described by these areas. |
|
Knuckle |
A slange term used when referring to some driveshaft joint parts and components. |
|
Liner |
A sound and vibrational deadening material added to the inside surfaces of a tube. |
|
Midship
Stub Shaft. |
A short shaft, generally splined, used in applications requiring more than one driveshaft. It mounts through the center of a support bearing and allows an additional driveshaft component to be fixed. |
|
Outside Lock-Up |
Term referring to either a cross and bearing kit or a yoke that utilizes a retaining ring in a groove near the outside edge of the yoke ear, rested against the outside face of the bearing cup. |
|
Phase/Phase
Angle |
The relative positioning of the universal joint yokes on a driveshaft or driveline. |
|
Retaining Ring |
A removable ring used as a shoulder to retain and position a round
bearing in a hole. |
|
Ring Groove
Round Bearing |
The surface used for positioning a round bearing with a retaining ring.
Consists of a round bearing cup with needle rollers designed to ride on a trunnion. |
|
Seal |
A flexible member which prevents the escape of lubricant and the
entrance of foreign matter. |
|
Slip Movement |
A permissible length of axial movement. |
|
Slip Stub Shaft |
A short, machined shaft, generally splined, which, when used with a slip yoke allows axial movement. |
|
Slip Yoke |
A yoke which allows axial movement. |
|
Snap Ring |
Same as RETAINING RING. |
|
ContentStrap Bearing Clamp |
A semi circular device that conforms to the bearing profile holding them in place in half round and some DC yokes. |
|
Swaged Tubing |
A tube with one or both ends having a smaller diameter then the middle section. |
|
Swing Diameter |
The maximum diameter of the circular path described by a rotating
universal joint. |
|
Thrust End |
The end of a cross trunnion used as a thrust surface. |
|
T.I.R. |
Total Indicator Reading on a specific point thru 1 revolution of a shaft. |
|
Torsional Damper |
A mechanical device, generally an inertia ring, attached to a drivetrain
component by means of a rubber inner ring to minimize driveline vibration in addition to balancing. |
|
Trunnion |
One of four projecting journals of a cross. |
|
Tubing |
The tubular connecting member of a driveshaft. |
|
Tube Diameter |
The outside diameter of a tube. |
|
Tube Yoke |
A yoke with a piloting hub for attachment of a tube. |
|
U-Bolt |
A clamping bolt with two parallel threaded legs used to retain a round bearing in certain end yoke designs. |
|
Universal Joint |
A device which can transmit torque and/or rotary motion from one shaft to another at fixed or varying angles of intersection of the shaft areas. |
|
Wall Thickness |
The measurement between the inside and outside diameter of a tube. |
|
Weld Yoke |
Same as tube yoke. |
|
Wing Bearing |
A member with a key and projecting wings used as the bearing base and positioning the thrust end of a cross trunnion. |
|
Yoke Shaft |
A one piece member designed to incorporate a tube yoke, tubing and stub shaft. It is used in close-couple applications and eliminates the need to use tubing. |
|
Zerk |
A lubrication fitting, usually threaded into a driveline component that will allow grease to be injected into the component, but does not allow grease to escape. |
