Curtis OL 812 Manuale Utente

 
 
 

CAP-215 

16 

 
 
4. VALVES 
 
4.1. 

 
 

The valve head of the first stage forms the top part 

 

of the cylinder.  The intake valve is fitted on the top 

 

of the piston.  The pressure valve is mounted between 

 

valve head and cylinder. 

 
 

Note that the valves are operated by the flow of 

 

the air.  On the suction stroke, the intake 

 

valves open and the air flows into the cylinders. 

 
 

At the start of the compression stroke the intake 

 

valve closes and the air opens the pressure valve, 

 

see Fig. 10. 

 
 
 
 
 
 
 
 
 

 

 

 

 

 

 

 

         Fig. 12:  Valve operation 1st stage 

 
 
 
 
4.2. 

 
 

The intake valve is fitted between valve head and 

 cylinder. 
 
 

On the suction stroke, the intake valves open and 

 

the air flows into the cylinders.  At the start of the 

 

compression stroke the intake valve closes and the 

 

air opens the pressure valve, see Fig. 11. 

 
 
 
 
 
 
 
 
 
 

 
 
 
 

Figure 13:  Valve operation 2nd stage