Lubricating system, bearing utilizing the system, universal joint utilizing the system, and process for production thereof

A lubricating system comprising a first foam lubricant containing a lubricating component in a resin thereof which foams, hardens and becomes porous;

• and a second lubricant for initial lubrication wherein said second lubricant is present together with said first foam lubricant in a portion to be lubricated,
• wherein in said first foam lubricant, said resin which foams, hardens and becomes porous is a rubber-like elastic substance;
• and said lubricating component contained in said resin has an exuding property displayed by deformation of said-rubber like elastic substance,
• wherein said second lubricant for initial lubrication consists of grease having a worked penetration not less than 300 or having a degree of oil separation not less than 0.7 wt % when said grease is left 24 hours at 70° C. or consist of lubricating oil having a kinematic viscosity not less than 50 mm2/second and 40° C.;
• and
• in initial lubrication of said lubricating system, said second lubricant for initial lubrication is essentially present at a sliding portion of said portion to be lubricated,
• wherein a foaming magnification of said resin is 1.1 to 100.

A universal joint in which a lubricating system is utilized, said lubricating system comprising a first foam lubricant containing a lubricating component in a resin thereof which foams, hardens, and becomes porous;

• and a second lubricant for initial lubrication wherein said second lubricant is present together with said first foam lubricant a portion to be lubricated, wherein in said first foam lubricant, said resin which foams, hardens and becomes porous is a rubber-like elastic substance;
• and said lubricating component contained in said resin has an exuding property displayed by deformation of said rubber-like elastic substance, wherein said second lubricant for initial lubrication consists of grease having a worked penetration no less than 300 or having a degree of oil separation not less than 0.7 wt % when said grease is left at 70° C. or consists of lubricating oil having a kinematic viscosity not less than 50 mm2/second at 40° C.;
• and in initial lubrication of said lubricating system, said second lubricant for initial lubrication is essentially present at a sliding portion of said portion to be lubricated,
• wherein a rotational torque is transmitted owing to engagement between track grooves and torque transmission members provided on an outer member and an inner member;
• said torque transmission members roll along said track grooves to allow said torque transmission members to move in an axial direction;
• and said first foam lubricant and said second lubricant for initial lubrication are present together in an inside of said universal joint, which is a portion to be lubricated, and
• in initial lubrication of said universal joint, said second lubricant for initial lubrication is present in a rolling portion of said universal joint in addition to said sliding portion.

A universal joint in which a lubricating system is utilized, said lubricating system comprising a first foam lubricant containing a lubricating component in a resin thereof which foams, hardens, and becomes porous;

• and a second lubricant foir initial lubrication wherein said second lubricant is present together with said first foam lubricant a portion to be lubricated, wherein in said first foam lubricant, said resin which foams, hardens and becomes porous is a rubber-like elastic substance;
• and said lubricating component contained in said resin has an exuding property displayed by deformation of said rubber-like elastic substance, wherein said second lubricant for initial lubrications consist of grease having a worked penetration not less than 300 or having a degree of oil separation not less than 0.7 wt % when said grease is left at 70° C. or consists of lubricating oil having a kinematic viscosity not less than 50 mm2/second at 40° C.;
• and in initial lubrication of said lubricating system, said second lubricant for initial lubrication is essentially present at a sliding portion of said portion to be lubricated,
• wherein a rotational torque is transmitted owing to engagement between track grooves and torque transmission members provided on an outer member and an inner member;
• said torque transmission members roll along said track grooves to allow said torque transmission members to move in an axial direction;
• and said first foam lubricant and said second lubricant for initial lubrication are present together in an inside of said universal joint, which is a portion to be lubricated, and
• in initial lubrication of said universal joint, said second lubricant for initial lubrication is present in a sliding portion of said universal joint.