Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
  • F04B43/00—Machines, pumps, or pumping installations having flexible working members
  • F04B43/12—Machines, pumps, or pumping installations having flexible working members having peristaltic action
  • F04B43/1253—Machines, pumps, or pumping installations having flexible working members having peristaltic action by using two or more rollers as squeezing elements, the rollers moving on an arc of a circle during squeezing

Definitions

• the invention relates to peristaltic pumping systems comprising a flexible tube, a series of rollers adapted to compress the flexible tube in a peristaltic way, a driving unit and a housing which comprises a preferable cylindrical raceway for receiving the flexible tube.
• a peristaltic pump unit of this kind is disclosed for instance in US 5 044 902.
• This unit discloses the use of a central shaft which is in direct contact with the rollers.
• the shaft has two functions, namely, driving the rollers during use and pushing them against the flexible tube when the shaft is inserted into the system.
• This unit shows however some disadvantages. For instance, it wears rapidly and frequently blocks due to the opposite rotation direction of adjacent rollers.
• One object of the invention is to provide a peristaltic pumping system of the type defined above, which is of a simple and robust construction and which allows an efficient pumping over prolonged period of time.
• the peristaltic pumping system comprises a flexible tube, a substantially cylindrical rotating roller unit containing a series of rollers which are freely rotating around their axes and freely moving along a radial segment, holding means for commonly holding the rollers, a central spreader element for pushing the rollers against the flexible tube and a driving unit comprising a driving coupling element, characterized by the fact that said holding means is made of at least one planar element having retaining and guiding means along such radial segment for rollers, said planar element being furthermore adapted to be directly coupled to said coupling element in such a way that rollers are driven through said planar element.
• the housing has preferably an internal groove with a concave cross-section into which is housed the flexible tube, while the rollers are externally barrel-shaped, with a convex curvature combined with the concave curvature of the groove of the housing, to rest against the flexible tube; such a housing with a concave internal profile allows a self-centering of the tube and the rollers.
• the tubular rollers are generally made of a flexible plastic material. Their shape is not limited to shape indicated previously. They may be cylindrical or conical. They may also be of a flexible material to improve the elastic functioning of the peristaltic pumping system.
• the driving unit preferably comprises a driving shaft provided with a support containing pins which are adapted to cooperate with holes in the planar element of the roller unit.
• the spreader is loosely mounted on an extension of the driving shaft to avoid any friction with the rollers during use.
• FIG. 1 of these drawings is a perspective view of a roller unit according to the invention.
• FIG. 2 is an enlarged view of a portion of the roller unit of fig. 1.
• FIG. 3 shows a peristaltic pump unit according to the invention including the roller unit, the housing, the driving shaft and the spreader.
• FIG. 4 represents the roller unit of fig. 1 containing the spreader.
• FIG. 5 is a longitudinal cross-section of the roller unit with the spreader-shaft arrangement in a non-active position.
• FIG. 6 is a longitudinal cross-section of the roller unit with the spreader-shaft arrangement in an active position.
• FIG. 7 is en enlarged view of a disc portion.
• a peristaltic pump system can be seen on figure 3, comprising a housing 9 containing a raceway 10 for receiving a flexible tube (not shown), forming the body of the pump.
• the tube is interposed between the housing walls and a roller unit 8,11 capable of co-operating with a support 2 fixed to a driving shaft 1 which is, in turn, driven by an electric motor (not shown).
• Figure 3 and 5 represents a non-active position where the driving shaft 1 has not penetrated the roller unit 8,11.
• the roller unit 8,11 is made of three rollers 11 held between two separator discs 8, the rollers 11 are commonly retained and guided through their axis ends 12 to the separator discs 8.
• At least one separator disc 8 contains a plurality of receiving means 13 which are adapted to receive the pins 3 of the driving support 2.
• the driving shaft distal end extends from the driving support 2 and is covered by a sheath 5 freely rotating around the driving shaft 1.
• the sheath 5 is sufficiently large in order to act as a spreader which pushes the rollers 11 against the flexible tube when the shaft distal end penetrates the roller unit 8,11 (see figures 4 and 6).
• the tube can be kept in position by two welded stop rings foreseen for being clamped into accurate recesses under the pressure of a supporting collar integral with the cover of the cartridge.
• this tube When manufactured in series, this tube is mounted very quickly into the cartridge.
• the peristaltic pump unit operates as follows :
• the housing 9 and the roller unit 8,11 are first placed on the driving unit 1 ,2 (see fig. 4 and 6) .
• the central shaft distal end, together with the sheath 5 pushes the rollers 11 against the tube and, in addition, the pins 3 engage the receiving means 13 of the discs 8.
• the coupling of said pin 3 in the receiving means can be self-aligned by having receiving means which are close to each other with a taper at the periphery to guide the pin into said receiving, said pin having a conical end.
• the coupling can also be obtained by pins being placed on the disc 8 and the receiving means being placed on the driving unit 2.
• the pumping action is obtained when the motor is started to rotate, driving the discs 8 and the rollers 11.
• the driving of the disc 8 can also be obtained by a gear coupling on the periphery of such planar disc.
• rollers 11 When the roller unit 8,11 and the housing 9 are separated from the driving unit 1,2 the rollers 11 are brought back to the centre under the pressure of the tube at rest, this tube remaining open.
• the rollers are not able to return to the center position once they have been pushed by the central shaft and sheath 5 against the flexible tube. In such a case, once the central shaft has been removed the peristaltic system remains occlusive, such as to prevent free-flow after use.
• this can also be obtained by having the sheath 5 remaining inside the roller unit 8,9 after the shaft is removed.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Reciprocating Pumps (AREA)
• Massaging Devices (AREA)
• Fertilizing (AREA)
• External Artificial Organs (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=34932087

Family Applications (1)

Country Status (6)

Cited By (4)

Families Citing this family (4)

Citations (4)

Family Cites Families (6)

• 2004
  • 2004-04-30 EP EP04405275A patent/EP1591660A1/en not_active Withdrawn
• 2005
  • 2005-04-27 US US11/587,438 patent/US8297956B2/en not_active Expired - Fee Related
  • 2005-04-27 AT AT05731140T patent/ATE394597T1/de not_active IP Right Cessation
  • 2005-04-27 WO PCT/IB2005/051372 patent/WO2005106251A1/en not_active Ceased
  • 2005-04-27 DE DE602005006552T patent/DE602005006552D1/de not_active Expired - Lifetime
  • 2005-04-27 JP JP2007510222A patent/JP4838237B2/ja not_active Expired - Fee Related
  • 2005-04-27 EP EP05731140A patent/EP1743100B1/en not_active Expired - Lifetime

Patent Citations (4)

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