Intermittent patient suction system and control means therefor

In an intermittent suction system having output means for alternately applying a vacuum and atmospheric pressure to a patient for removing fluids from said patient and wherein said system includes a vacuum source and first and second container means adapted to be interconnected to operating means of control means and to said source and said atmospheric pressure by said operating means of said control means that is adapted to apply said vacuum through said output means to said patient in response to a vacuum condition of said first container means and to apply said atmospheric pressure through said output means to said patient in response to a vacuum condition in said second container means, the improvement comprising means in said operating means of said control means for always interconnecting said vacuum through said output means to said patient when said vacuum condition in said first container means is a certain percentage of the vacuum condition of said source regardless of the vacuum value of said source so as to prevent any adverse interruption in said system during the use thereof for said patient should the vacuum level of said source fall to an undesirable level.