PRM Delta

[RLWP]

Like the PRM 160 this is a hydraulic, constant mesh gearbox with two plate clutches. The main differences are that the case is aluminium and splits perpendicular to the shafts, and everything is a lot smaller and lighter.

 

Building up the gearbox, we start with the input shaft:

 

 

This shaft has the input splines on the right and the reverse gear drive gear on the left

 

The drive gear contains a concentric piston (the big ring thing):

 

 

Onto this shaft goes the forward gear clutch. The PRM clutch kit is very comprehensive, having all of the wearing parts and fixings:

 

 

The clutch pack starts with a driven plate:

 

 

The tubes are carried on the fixing bolts and push the driveplates around. The springs are to disengage the clutch

 

Alternating with the driveplates are the driven plates (!):

 

 

The teeth in the middle of these engage with a spline on the output gear.

 

This is the whole assembly with the output gear installed:

 

 

Here we have the three shafts in the rear half of the casing:

 

 

Top right is the input shaft, top left is the reverse shaft permanently meshed with the input shaft. At the bottom is the output shaft.

 

Here we have the output gear installed:

 

 

The output shaft gear meshes with the two output gears, one on the input/forward shaft and one on the reverse shaft.

 

Richard

[n.b.Goldie]

Many thanks for this and the thread showing the driveplate workings.

The Delta has been superceded by the PRM 150. I am told many of the parts are interchangeable excepting the output shaft which is beefier on the 150.

 

My question is regarding mating the gearbox to the driveplate. I have been told that a Delta 'box can be mated to a 150 driveplate but not vice-versa because the 150 output shaft is too large for a Delta driveplate. The last bit I understand but surely the Delta output shaft would be a very loose fit in a 150 driveplate and 'chatter' causing premature wear. What do you think?

 

Regards

Ditchdabbler

[RLWP]

I can't see they would be at all compatible, the 150 shaft is very different. I have one in the workshop somewhere, I'll put a photo up for you when I find it

 

The casings are different too, as is the pump housing, and I think it has different bearings

 

Richard

Edited December 3, 2012 by RLWP

[system 4-50]

Engineering porn! Drool!

[RLWP]

Right.

 

PRM Delta input shaft:

 

 

PRM 150 input shaft:

 

 

PRM 150 shaft with PRM Delta driveplate:

 

 

The shaft of the Delta would sit in the middle of a 150 driveplate without touching or driving

 

More on the PRM Delta on my website, including this:

 

 

Richard

Edited December 3, 2012 by RLWP

[n.b.Goldie]

Thank you that was very clear.

 

Much appreciated.

 

Regards

Ditchdabbler

[RLWP]

 

To finish off the Delta box,

 

On the end of the input shaft is a gear pump:

 

 

 

 

 

The top image shows the gears in their housing, the bottom one shows the feed and delivery pipes. Oil is drawn in from one of the holes, travels around the outside of the gears and exits through the other hole.

 

It is this oil that makes the gearbox work. Oil is pumped into the space behind the piston on one of the gear/clutch clusters, squeezing the clutch plates together and locking the output gear to the output shaft

 

Richard

Edited December 3, 2012 by RLWP