Spring retainer for a poppet valve and method of assembling

An apparatus comprising:

• a poppet valve having a valve stem with an axis, said valve stem having a groove;
• a valve spring for biasing said poppet valve, said valve spring having a plurality of coils which encircle said valve stem;
• and
• a spring retainer for retaining said valve spring, said spring retainer having first and second body portions, each of said first and second body portions having surface means for defining a central opening extending through said spring retainer, said central opening being coaxial with said valve stem, each of said first and second body portions having a spring engagement surface means for engaging said valve spring and for receiving a spring force from said valve spring, each of said first and second body portions having finger means for engaging said valve stem and for extending into said groove on said valve stem to lock said spring retainer to said valve stem;
• said spring retainer having frangible means for retaining said first and second body portions together as a unitary part prior to installation of said spring retainer on said poppet valve and for breaking during installation of said spring retainer on said poppet valve to permit relative outward movement of said first and second body portions to permit passage of said valve stem between said first and second body portions during installation.

A method of assembling a poppet valve, a valve spring and a spring retainer, the spring retainer having a body with first and second body portions, the spring retainer having a frangible connector web located between the first and second body portions, said method comprising:

• locating the valve spring concentrically about a valve stem of the poppet valve;
• axially aligning a central opening of the spring retainer with the valve stem;
• engaging a spring flange segment on each of the first and second body portions with the valve spring;
• engaging a tip portion of the valve stem with a finger segment of each of the first and second body portions;
• moving the spring retainer axially relative to the valve stem by applying an axial force to the spring retainer to cause the tip portion of the valve stem to pass through the central opening of the spring retainer;
• compressing the valve spring due to force applied to the valve spring by the spring flange segments as the spring retainer moves axially relative to the valve stem;
• breaking the frangible connector web between the first and second body portions such that said first body portion is separated from said second body portion as the spring retainer moves axially relative to the valve stem;
• relatively moving the first and second body portions due to force applied to the first and second body portions by the tip portion of the valve stem including pivoting the finger segments outward and pushing the first and second body portions outward relative to the valve stem;
• and
• pivoting the finger segments inward into a groove on the valve stem to lock the spring retainer onto the valve stem.