초록 ▼

A vacuum controller for controlling the vacuum at a controlled vacuum which includes a balanced piston arrangement coupled to a valve piston reciprocal with respet to a valve seat positioned between the controlled vacuum and a high header or source vacuum. A throttling of the header vacuum takes pla

A vacuum controller for controlling the vacuum at a controlled vacuum which includes a balanced piston arrangement coupled to a valve piston reciprocal with respet to a valve seat positioned between the controlled vacuum and a high header or source vacuum. A throttling of the header vacuum takes place across the space between the valve piston and valve seat and is such that the header vacuum does not influence the movement of the valve piston.

대표청구항 ▼

A vacuum controller for controlling the amount of vacuum at a location, said controller comprising: a housing; means for connecting said housing to a source of vacuum; means for connecting said housing to a control vacuum; balance piston means disposed in said housing and reciprocal therein, said pi

A vacuum controller for controlling the amount of vacuum at a location, said controller comprising: a housing; means for connecting said housing to a source of vacuum; means for connecting said housing to a control vacuum; balance piston means disposed in said housing and reciprocal therein, said piston means including first piston means reciprocal in a chamber and responsive to a control pressure in said chamber regulating the movement of said balance piston means therein; value piston coupled to the balance piston means so as to provide a concentric unbiased loading of said valve piston wherein movement of said balance piston means causes a corresponding movement of the valve piston; valve seat means positioned between the source vacuum and the controlled vacuum; said valve seat means adapted to receive said valve piston which is reciprocal with respect thereto between a fully open position and a fully closed position so as to regulate the amount of vacuum provided by the source vacuum to the controlled vacuum; and wherein a throttling of the source vacuum with respect to the controlled vacuum occurs between said valve piston and said valve seat such that the source vacuum does not influence the movement of the valve piston between said positions for throttling purposes and the valve piston remains balanced throughout its movement.