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US 4,292,887 AGranted
Power servo booster
AssigneeJidosha Kiki Co., Ltd.
InventorsRyuji Ohta, Yoshimichi Inoue
Life of this patent
Estimating the term…
Abstract
A power servo of the fluid differential type having a power piston and a diaphragm defining two cavities maintained at a differential pressure. An air passage is formed to release any air present in a space between the diaphragm and the disc portion of the power piston. The air passage may be formed as a split groove in the flange or as a hole through it. The groove may be either circumferential or axial to allow air to escape into the atmospheric chamber of the power servo.
Claims9
A power servo operable by differential pressure comprising:
- a housing, a unitary piston disposed in said housing, a control member coupled to said piston, said unitary piston including a disc element and a flange portion with an annular groove formed between said disc and said flange, a diaphragm member secured at its outer periphery to said housing to divide said housing into two compartments one compartment a negative pressure chamber and the other an atmospheric pressure chamber, said diaphragm member having a generally cylindrical section and an inner peripheral portion secured in said annular groove, means disposed in said negative pressure chamber for biasing said unitary piston toward said atmospheric pressure chamber and means associated with said annular groove for defining a path of fluid communication from the atmospheric pressure chamber to a space formed between said diaphragm and said disc.
A power servo operable by differential pressure comprising:
- a housing, a piston disposed in said housing, a control member coupled to said piston, said piston including a disc element and a flange portion with an annular groove formed between said disc and said flange, a diaphragm member secured at its outer periphery to said housing to divide said housing into two compartments one compartment a negative pressure chamber and the other an atmospheric pressure chamber, said diaphragm member having a generally cylindrical section and an inner peripheral portion secured in said annular groove, means disposed in said negative pressure chamber for biasing said piston toward said atmospheric pressure chamber and, means associated with said annular groove for defining a path of fluid communication from the atmospheric pressure chamber to a space formed between said diaphragm and said disc comprising a pair of protrusions formed in said annular groove and a split groove formed in said flange portion, the width of said split groove corresponding substantially to the distance between said protrusions, whereby an air passage is formed between said protrusions and under the inner peripheral portion of said diaphragm.
Dependencies are inferred from the claim text.