Hamilton Jet HJ241, Manual

Page: 42 / 202

3.8
3 DESIGN BASICS
3.3 D
RIVELINES
HJ-241 / HSRX
3.3.3 Drive Shaft Options
The diagrams Figure 15: Double Universal Slip joint-
ed Driveshaft and Figure 16: Torsionally Flexible Fly-
wheel Coupling show two common Driveline
components and their arrangements. These
diagrams are a guide only. Always contact C.W.F.
Hamilton & Co. Ltd before designing the Driveline.
UNIVERSAL DRIVESHAFTS:
These are double universal slip-jointed Driveshafts,
also called Cardan shafts. They bolt directly to the
Jet Unit Coupling.
Lengths range from approximately 900 mm to
3,000 mm. Lengths are limited by the weight
which can be allowed at the Jet Unit Coupling.
(Refer to Section 3.3.7 Critical Speed of Mainshaft
and Section 3.3.2 Engineering Checks ).
TORSIONALLY FLEXIBLE COUPLING (TFC):
The torsional vibration analysis will determine how
many TFC’s are required and where they should be
located. At least one TFC should be fitted either:
• Between the engine and the gearbox.
• Immediately between the gearbox and any
shafting leading to the Jet Unit.
DOUBLE ELEMENT TORSIONALLY FLEXIBLE COU-
PLINGS:
Examples of such couplings are "Centaflex" and
"Megaflex".
Use a double element torsionally flexible driveshaft
with support bearings such as the "Centaflex GZ"
type illustrated. The engine is located In-line with
the Jet Unit and can be flexibly mounted with this
type of coupling.
Length - From approximately 200 mm (8")
upwards, but limited by the weight which can be
allowed at the Jet Unit coupling.
Refer to Section
3.3.7 Critical Speed of Mainshaft .
DOUBLE ELEMENT NON TORSIONALLY FLEXIBLE
COUPLINGS:
An example of such a Coupling is "Centalink".
GEAR COUPLINGS:
This Coupling is steel double -jointed coupling
which is both flexible to allow for angular offset and
also rigid to absorb torsional twisting.
The Coupling is formed by two hubs which engage
into a flanged sleeve with internal straight parallel
teeth. Due to the design of the of the teeth
curvature, if shaft misalignment occurs, the hub can
oscillate in the flanged sleeve.
Figure 15: Double Universal Slip jointed Driveshaft
Figure 16: Torsionally Flexible Flywheel Coupling
DRIVESHAFT
DOUBLE UNIVERSAL SLIP JOINTED
FLYWHEEL ADAPTOR
YOKES IN SAME PLANE
OFFSET ANGLES EQUAL
JET COUPLING
A°
ENGINE FLYWHEEL
A°
Figure 17: Double Element Torsionally Flexible Coupling