Peristaltic pump

Claim 1

A peristaltic pump, comprising in combination: a. a housing including spaced apart tube supports for holding tubing between said supports; b. a drum rotor member with a central drive shaft to drive said drum rotor member disposed between said tube supports, the drive shaft being disposed normal to tubing extending between said tube supports, with rollers disposed around the periphery of said dRum rotor member parallel to said drive shaft so as to engage tubing extending between said tube supports, also bearing assemblies including a flexible inner center disposed in said housing to support said drive shaft for rotation; c. a floating arcuate press plate, said press plate forming a section of a cylinder whose axis somewhat coincides with said drum axis, the concave side of said press plate being disposed over said drum rotor member and generally conforming to the curvature of said drum rotor member, said press plate serving to hold tubing against said rollers, said press plate having at least two arcuate longitudinal ridges parallel to tubing extending between said tube supports, said ridges preventing the tubing from being pressed beyond its elastic limits; and, d. extended support means disposed over said press plate and connected to said housing, said press plate connected to said support means by loose connecting means allowing said press plate considerable movement up and down and from side to side over a wide space, whereby when the drum rotor member rotates, the rollers pass over the flexible tubing successively to drive liquid in the flexible tubing in the same direction as the motion of the rotor, the press plate assuming different positions so as to conform to variations in the height and position of said rollers, the press plate floating while being spring loaded, correcting for lack of alignment and circularity of the drum rotor member.