A rose joint and a spherical joint are basically the same.. 'rose' is a generic term usually applied to a range of non-booted universal spherical joints.. they were originally made by the Rose manufacturing company.. the story goes that they were copies of joints taken from a shot down German aircraft.. anyway I digress..
The joints on our cars are usually referred to as spherical joints.. they also have a nylon insert..
Both types come in all different sizes and applications and both are often referred to as Rose joint.Spherical joint.. Ball joint... in other words take your pick
So to sum up they are all basically a caged ball with a hole drilled through it.. sometimes a male spigot is attached to the ball.. just like the steering rack joints which are also called Track rod ends.. confusing innit!
The picture on the left is a pair of Alfa GTV springpan joints.. the one on the right is a Rose joint..
Road car applications usually use rubber joints as they are a lot more resiliant and give a more comfortable ride at the expence of precision suspension control. Ball joints which are not resiliant at all, give better suspension control at the expence of comfort.. Poly /Powerfex is somewhere between the two..
My track car was fitted with all Rose Joints and was un-drivable on normal public roads..
Ball/ Rose/ Spherical Joints for motor vehicle applications are usually protected by a rubber boot or cover to prevent the ingress of dirt/grit etc.. applications such as race cars, aircraft etc. can be left open.. no dirt!!
or at least the maintenance regime is so tight that they are checked a lot more frequently..
So it was invented by German engineers.. copied by British engineers while the Italian engineers were designing beautiful cars to impress the girls with.. Meccanica Aventura