Intermittent patient suction system, self-contained control

Claim 1

In a self-contained control device for an intermittent suction system and having operating means and output means for alternately applying a vacuum and atmospheric pressure to a patient for removing fluids from said patient, said system including a vacuum source and first and second container means adapted to be interconnected to said operating means of said control device and to said source and said atmospheric pressure by said operating means of said control device 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, said operating means of said control device having 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, said control device having a housing means, and two restrictor means for respectively controlling the "on" time and "off" time that said control device applies said vacuum and does not apply said vacuum through said output means to said patient, said housing means comprising a plurality of plates disposed in stacked relation so that two of said plates define outer plates and the remainder of said plates define inner plates, the improvement wherein said restrictor means are carried solely by one of said inner plates of said housing means.