Peristaltic pump

Abstract

A peristaltic pump including a support surface including an interior face, a drive device for driving the rotation of rollers so as to compress the tube at least at one point on the interior face of the support surface, this drive device being a direct-drive device.The peristaltic pump includes: a central roller, positioned between the rollers and in contact therewith, the central roller forming a central point of contact for relaying the load applied to the at least one roller compressing the deformable tube against the interior face;a geared drive device for driving the rotation of the rollers so as to compress the tube at least at one point on the interior face of the support surface; and/orthe central roller driving the frictionally rotation of the rollers;where the pump is offers, using the same set of rollers, at least three different reduction ratios.

What is claimed is: 
     
         1 . A peristaltic pump intended to operate with a deformable tube, said peristaltic pump comprising a support surface comprising an interior face, a drive device for driving the rotation of the rollers so as to compress said tube at least at one point on the interior face of said support surface, this drive device being a direct-drive device, characterized in that
 said peristaltic pump comprises a central roller, positioned between said rollers and in contact therewith, said central roller forming a central point of contact for relaying the load applied to said at least one roller compressing said deformable tube against said interior face, said central roller having a longitudinal axis,   said peristaltic pump comprises a gearwheel support element which is pierced at its center and comprises pins on at least one of its faces to support peripheral gearwheels, a central gearwheel engaging with said peripheral gearwheels so as to drive same, the assembly forming a geared drive device for driving the rotation of said rollers so as to compress said tube at least at one point on the interior face of said support surface, and/or   said central roller comprises an orifice extending along its longitudinal axis and opening onto at least one of the lateral edges of said roller, said orifice having a female socket shape configured to be connected to the shaft of a motor for driving the rotation of said roller and, therefore, for driving the rotation of said rollers, this rotational driving of said rollers being what is known as friction drive, and   said peristaltic pump is thus configured to offer, using the same set of rollers, at least two different reduction ratios when it has two of said devices for driving the rollers, and at least three different reduction ratios when it comprises all three devices for driving the rollers.   
     
     
         2 . The peristaltic pump according to  claim 1 , characterized in that, with said peristaltic pump comprising a device for the geared driving of the rollers and with said central roller comprising an orifice extending along its longitudinal axis and opening onto at least one of its lateral edges, said central gearwheel is removable so as to allow just the central roller to be driven directly by the shaft of a motor so as to drive the rotation of said rollers by friction, said peristaltic pump thus offering a third different geared-down reduction ratio. 
     
     
         3 . The peristaltic pump according to  claim 1 , characterized in that, with said peristaltic pump comprising a device for the geared driving of the rollers, one lateral edge, or end, of said central roller is inserted into the central hole in said gearwheel support element in order to support said central roller. 
     
     
         4 . The peristaltic pump according to  claim 1 , characterized in that, with said peristaltic pump comprising a device for the geared driving of the rollers and with said gearwheel support element comprising pins for supporting said rollers and thus forming a separator, said peristaltic pump comprises a single separator and is said to be a single-separator pump, the central hole in this separator determining a female socket that complements the male end shape of the shaft of a motor so that these can be assembled by fitting the one into the other so as to allow direct rotational drive of said rollers. 
     
     
         5 . The peristaltic pump according to  claim 4 , characterized in that said central roller is configured to maintain its position between said rollers. 
     
     
         6 . The peristaltic pump according to  claim 5 , characterized in that, with said central roller having a longitudinal dimension greater than that of the rollers, each of its lateral edges, or ends, has a flared shape or a boss to prevent movement of said central roller along the main axis about which said rollers are rotationally driven by said geared driving device. 
     
     
         7 . The peristaltic pump according to Claims  claim 1 , characterized in that, with said gearwheel support element also comprising pins for supporting said rollers and thus forming a first separator, it comprises a second separator pierced at its center and comprising pins on at least one of its faces, said first and second separators defining a cage to receive and support at least said rollers and the central roller, said second separator comprising a central hole supporting a pinion intended to be driven directly by a shaft of a motor in order to drive the rotation of said rollers, or this central hole in said second separator defining a female socket that complements the male end shape of the shaft of a motor so that these can be assembled by fitting the one into the other so as to allow direct rotational drive of said rollers. 
     
     
         8 . The peristaltic pump according to  claim 1 , characterized in that, with said pump comprising n rollers, said gearwheel support element comprising pins for supporting said rollers and thus forming a separator, said or at least one of said separators comprises two opposite faces, at least one of said faces receiving at least two sets of n pins, the n pins of a first set being distributed on a circle of diameter D and the n pins of another set being distributed on a circle of diameter G so as to define two distinct reduction ratios for said peristaltic pump using corresponding rollers. 
     
     
         9 . The peristaltic pump according to  claim 1 , characterized in that, with said pump comprising n rollers, said gearwheel support element comprising pins for supporting said rollers and thus forming a separator, said or at least one of said separators comprises at least two sets of n holes distributed on corresponding circles of different diameters and a single set of n spindles so as to form, with each set of holes, pins for supporting corresponding rollers, said sets of n holes defining distinct reduction ratios for said peristaltic pump. 
     
     
         10 . The peristaltic pump according to  claim 1 , characterized in that it is configured in such a way that this secondary, so-called friction, driving of said rollers by said central roller combines with the geared-driving of the rotation of said rollers the drive thus formed being said to be hybrid. 
     
     
         11 . The peristaltic pump according to  claim 10 , characterized in that, with said peristaltic pump comprising a geared-drive device for driving the rollers and said central roller of comprising an orifice extending along its longitudinal axis and opening onto at least one of its lateral edges, said central gearwheel has a hole placed facing the orifice of said central roller, the hole in said gearwheel and the orifice of said roller having the same female socket shape that complements the male shape of the shaft of a motor so that these can be assembled by fitting the one into the other so as to allow rotational driving of said rollers and of said central roller. 
     
     
         12 . The peristaltic pump according to  claim 10 , characterized in that, with said peristaltic pump comprising a device for the geared driving of the rollers and said central roller comprising an orifice extending along its longitudinal axis and opening onto at least one of its lateral edges, said central gearwheel comprises an assembly element projecting from its opposite face from the one that is intended to face toward the motor, said assembly element being configured for assembling this central gearwheel with said central roller. 
     
     
         13 . The peristaltic pump according to  claim 7 , characterized in that it comprises an externally-toothed gearwheel supported by a separator distinct from said gearwheel support element, an assembly element projecting from the opposite face of this externally-toothed gearwheel from the face that is intended to face toward the motor, said assembly element being configured to allow assembly of said externally-toothed gearwheel and of said central roller, or a central opening configured to house one end of said central roller and allow it to be assembled with said central roller, said peristaltic pump additionally comprising an individual component of which the periphery or external surface defines a shape, such as a square or hexagonal shape, intended to collaborate with an orifice of complementary shape belonging to a separator of said peristaltic pump, said individual component having a central orifice configured to allow the passage of the end of said central roller. 
     
     
         14 . The peristaltic pump according to  claim 1  characterized in that the components that make up said pump are made of plastic, the body of the peristaltic pump, also known as the pump casing, being made as two half-casings assembled with one another, said half-casings being identical. 
     
     
         15 . A preassembled subassembly comprising a peristaltic pump according to  claim 1  and a peristaltic-pump deformable tube.