Patent attributes
A valve having a first segment between a first outer wall and a first inner wall and has a first outer port near the first outer wall and a side port between the first inner and outer walls; a second segment between a second outer wall and a second inner wall and has a second outer port near the second outer wall; a center segment between the first and second inner walls, and a center port; and a piston within the valve, having: a first piston head in the first segment that slides to block and unblock the side port; a second piston head in the second segment that slides between the second inner and outer walls, the second piston head having a surface area that is the same as the first piston head; and a shaft connecting the first and second piston heads.
