Need help identifying this universal joint

[John Fitzpatrick]

I can't find any information for this sort of U-joint. It acts as a U-joint between the transaxle and the driveshaft and allows the driveshaft to move in and out horizontally. I think most of the contemporary cars I've seen either used the rubber donut along with the Spicer type U joint or U joint with a splined shaft and tube. Some questions-
What is the proper name for this part?
Why would it have been used in preference to the donut style?
It allows for sliding movement but doesn't provide dampening. Is that a potential problem in some instances?
Was it safe and reliable?

Thanks, I've been wondering about this for several years now, and finally got off by butt and took some photos.
John

 

[Robert May Eng.]

Its no different in principle to the peugeot type inner cv. Still in use today.

Bob

 

[Michel]

This U joint is named "tripode "

It moves horizontaly to allow cinematic of suspension
It is much more effective in torque for less weight
It is more reliable than a cv joint due to only 3 big spherical balls instade of 6 small

 

[John Oxborough]

John,
The joint in your picture is a "ball and trunnion" type, this type of joint was used on Rolls Royce Silver Shadow cars 1965 onwards,
The joint in Bobs picture is indeed a "triplode" ,so called due to having 3 bearings/trunnions.
On the Rolls Royce the joint was filled with EP90 oil via a level plug all very nicely engineered, fine until the gaiter failed , oil disappeared and joint filled up with debris and an expensive and time consuming rebuild, shimming the trunnions to be dead central to avoid axle vibration.
cheers,
John.

 

[jyrki sulka]

Typical tripod problem is weak bowl.
It`ll stretch and-or crack, cousing vibrations.

In Ford-europe -world this is common problem in front driveshafts of 4x4 Sierra/Escort/Cosworth. I even tried steel support sleeves and "billett" -versions of bowl, no luck, both rally and road cars. Moving to Gr A cv`s; no problems.
And out of box standard Mondeos and Focuses, same thing.

My choice is cv (löbro-quality) instead of tripod anyday.

 

[John Fitzpatrick]

John-
Thank you--now I'll know to call it when it falls on my hand next time! Damn thing weighs a ton, and the integral solid driveshaft is a good 1-1/2" thick. I'm not surprised RR used one like it after watching the Top Gear episode with the RR (I think the term "canal boat" was used at some point) since it isn't going to wear out in our lifetime!
John

 

[Wally]

Hi John This looks like the ones used in Mopars in the 50s & 60s. Haven't seen one in years. Wally

 

[John Fitzpatrick]

John,
I know the inner arms of two drive shaft universal joints should be coplanar, and I can visualize why that's necessary, but I can't for the life of me visualize how the motion of a tripod (or is that "tripload"?) on one end of a shaft could compensate for the variations in rotational speed of a standard U-joint on the other.
Would you have to use one at each end of the driveshaft?

 

[Robert May Eng.]

Its an oddball design. The uj on one end of the driveshaft is going to be pumping the other joint in and out of its housing on every revolution of the shaft on anything other than straight. Thats not to mention the suspension movement, thats going to be one busy little joint in that housing.

Bob