Triumph TR6 PI Operation Manual page 280

SOLENOID AND OPERATING VALVE
Energising
The solenoid and operating valve are a self contained
factory sealed unit, situated on the main case of the
overdrive.
The solenoid has a single coil, encapsulated and
completely waterproof, with a continuous current
consumption of approximately 2 amperes. There are no
electrical contacts in the solenoid.
In direct drive a residual pressure of approximately
20 p.s.i. maintains the system in primed condition and
provides lubrication. This is achieved by the relief valve
piston reacting on the residual pressure spring. When
overdrive is engaged pressure increases to a pre-determined
operating pressure of 430/460 p.s.i. When the solenoid is
energised, its valve opens and oil which is at residual
pressure is directed via passage
'z'
to the bottom of the
dashpot piston. This causes the dashpot piston to rise and
compress the dashpot spring causing a progressive increase
in hydraulic pressure until the piston reaches its stop by
which time the relief valve spring has been compressed to
its working length, thus giving full operating pressure. This
pressure causes the operating pistons to move forward
overcoming the clutch springs and engages the cone clutch
in the brake ring.
4
4
PT 2301
KEY
I. Pressure filter.
2. Cam.
3. Input shaft.
4. Operating pistons.
5. To central lubrication.
40.00.09J
6. Solenoid valve.
7. Dashpot.
8. Passage Z.
9. Relief valve.
10. Pump.
Triumph TR6 ManuaL Part No. 545277 I..ue I
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