Engine speed governor with peak load control

Claim 1

A maximum-minimum speed limiting governor in combination with a compression-ignition engine having a fuel rack actuator for varying fuel input to the cylinders, said governor comprising a housing, first actuating means in said housing and connectible with such fuel rack actuator, said actuating means being movable between maximum and minimum fuel positions, engine speed responsive means in said housing and connected with said first actuating means, said speed responsive means being movable between maximum and minimum speed positions and arranged such that movement thereof toward said maximum speed position moves said first actuating means toward its minimum fuel position and movement of said speed responsive means toward its minimum speed position moves said first actuating means toward its maximum fuel position, support means in said housing and having a cylindrical bore with an annular abutment surrounding said bore at one end thereof, a cylindrical plunger received for reciprocating movement in said bore, said plunger having an annular flange extending axially opposite said abutment, a cap member reciprocably received within a recess in said plunger and low speed spring means in said recess and biasing said cap member outwardly therefrom and into engagement with and urging said speed respoNsive means toward its maximum speed position, said cap member having a flange stop thereon engagable with the end of said plunger to limit compression of said low speed spring and provide a non-yielding connection between said plunger and said speed responsive means at operating speeds above a preset engine idle speed, a high speed spring received on said plunger and acting between said annular flange and said housing so as to bias said annular flange toward said support abutment, and a peak load control spring acting between said abutment and said annular flange and opposing the bias of said high speed spring during the initial portion of the travel of said plunger flange away from said abutment, said speed responsive means being operable to apply a force increasing with increasing engine speed against said low and high speed springs through said cap member and plunger such that said low speed spring is partially compressed in the idle speed range and said high speed spring is partially compressed in the maximum speed range, said peak load control spring acting to reduce the maximum engine fuel input near the maximum speed range so as to maintain a relatively constant maximum engine horsepower over a range of operating speeds adjacent the maximum speed range.