Abstract: A method of manufacturing a conical valve seat, wherein the valve seat surface is placed in alignment with a cutting edge of a pattern impression pin, a predetermined amount of pressure is applied to the valve seat to move the seat surface relative to the cutting edge of a pattern impression pin to form a groove in the seat surface, hardening the seat member, and then grinding a conical surface on the seat surface to finish it.

Abstract: The conical valve seat in the valve body of a fuel injector has a circumferential groove means forming a pocket to capture an amount of the fuel that flows through the injector. The needle valve seals and seats on the downstream edge of the groove means, but is not in contact with the upstream edge. The groove means functions to improve "durability wear" of the components and as a result eliminates a "lean shift" in the dynamic flow rate of the injector. In addition the groove means functions as a dampening means to the closing of the needle on the valve seat. In the manufacturing of the conical valve seat, the valve seat is fabricated, the groove means is formed, the valve seat is then hardened and a light grind smoothes out the valve seat.

Abstract: A solenoid valve that is to be used to control flow of a liquid medium is tested in a test fixture which applies a leak test, a flow test, and a response test using a gas as a test medium. The test results are compared with a test specification that has been previously derived from an established correlation of tests using gas as a test medium versus liquid as a test medium. The invention enables the valves to be tested with gas instead of liquid.

Abstract: A multiple spindle automatic screw machine is provided with an electrically insulated metal stock feed stop which is connected in an electrical circuit so as to provide an electrical signal when the grounded bar stock makes contact therewith for indicating part count and stock presence.