| 摘要 |
An annular valve seat 2 for an EGR valve having a tapered or conical valve head 4, the valve seat 2 having a cooperating conical contact face 8, said contact face having a plurality of radially spaced regions 12 having a width in a substantially axial direction greater than the width of regions 10 of the valve seat therebetween, such that the contact area between the valve seat 2 and valve head 4 in said spaced regions is greater than the contact area between the valve seat 2 and the valve head 4 in the regions between said spaced regions. |
