Abstract A combination equalizer and over-pressure control for use with fluid compressors comprises a passage having a first piston including a relief port therethrough, the piston when in a first position preventing any flow of fluid through a second relief port. A second piston, disposed upstream of the first piston, is movable relative thereto. A first spring provides a force to maintain the second piston in spaced relationship relative to the first piston, the second piston moving into sealing abutment with the first piston to close the first relief port when fluid pressure acting on the second piston exceeds a predetermined value. A second spring provides a force to maintain the first and second pistons in position relative to the second relief port to prevent any fluid flow therethrough. The first and second pistons move jointly at a predetermined over-pressure condition to open the second relief port. Upon the deenergization of the fluid compressor the second piston moves relative to the first piston, whereby the first relief port is opened to relatively quickly equalize pressures across the control.
A combination equalizer and over pressure control for use with fluid compressors comprising: a. a housing defining a chamber with a flange-like wall at one end thereof; b. means forming a passage adapted to conduct pressure fluid, and including a first piston-like member having a first relief port therethrough, and when in a first position preventing any flow of fluid through a second relief port; c. means for closing said relief port including a second piston-like member disposed upstream of said first piston-like member, said first and second members being movable relative to one another; d. control means including first force supplying means disposed between said first and second piston-like members to bias said second member away from said first member, said second member moving into sealing abutment with said first member to close said first relief port when fluid pressure acting on said second member exceeds a predetermined value, and second means providing a force to maintain said first and second members in position relative to said second relief port to prevent any fluid flow therethrough, said first and second members moving jointly at a predetermined over pressure condition to open said second relief port; and e. said first force supplying means moving said second member relative to said first member to bias said second piston-like member toward said wall of said housing when the fluid compressor becomes inoperable thereby opening said first relief port, said second member including abutment means contacting said wall to maintain said passage means in an open state when said first relief port is opened to relatively quickly equalize pressure across said control.
Claim 2
Dependent Claim
269 words
A combination equalizer and over pressure control for use with fluid compressors comprising: a. a housing defining a chamber with a flange-like wall at one end thereof; b. means forming a passage adapted to conduct pressure fluid, and including a first piston-like member having a first relief port therethrough, and when in a first position preventing any flow of fluid through a second relief port; c. means for closing said relief port including a second piston-like member disposed upstream of said first piston-like member, said first and second members being movable relative to one another; d. control means including first force supplying means disposed between said first and second piston-like members to bias said second member away from said first member, said second member moving into sealing abutment with said first member to close said first relief port when fluid pressure acting on said second member exceeds a predetermined value, and second means providing a force to maintain said first and second members in position relative to said second relief port to prevent any fluid flow therethrough, said first and second members moving jointly at a predetermined over pressure condition to open said second relief port; and e. said first force supplying means moving said second member relative to said first member to bias said second piston-like member toward said wall of said housing when the fluid compressor becomes inoperable thereby opening said first relief port, said second member including abutment means contacting said wall to maintain said passage means in an open state when said first relief port is opened to relatively quickly equalize pressure across said control.