RevisionC-Developmentofconceptofcompressorforcommercialvehicle

element to Valve lift Inlet valve Cylinder bore Delivery valve stopper Delivery valve Cylinder bore
Valve lift return to the seat lands and close the valve on time. Preferably, the valve is completely
closed when the piston is at or near dead centre.
A reed valve is a flow actuated one-way valve. A port in the line is covered by the free
end of a thin and flexible blade whose other end is fastened so that the port is normally closed.
Pressure in the port or vacuum on the far side, will lift the blade, permitting the flow. If the pressure
reverses, it closes the blade, stopping the flow. Usually the reed valves use a single blade, but
modern versions combine four, six or eight blades, or petals, into tent-like arrays, fastened to a
multi-ported reed cage. Reed valve involves the loss of pressure, as some pressure difference is
required to open the valve. Even with this limitation, they have excellent versatility. Figure 3.3
shows the inlet and delivery valves employed in a 160-cc air cooled compressor.
Figure 2:6: Inlet and Delivery disc valve openings
Modern compressors employ reed valves because of the following features:
• Number of components required is less. So almost no wear takes place.
• The number of holes in the valve plate can be increased which will increase the
flow area. This will reduce the pressure required to open the valves, and hence
lesser pressure drop across the valves.
• Lesser assembly difficulties.
Page 27 of 93