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
  • F04B43/08—Machines, pumps, or pumping installations having flexible working members having tubular flexible members
  • F04B43/09—Pumps having electric drive
• • 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
  • F04B43/0009—Special features
  • F04B43/0054—Special features particularities of the flexible members
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
  • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
  • F04C2/00—Rotary-piston machines or pumps
  • F04C2/02—Rotary-piston machines or pumps of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents
  • F04C2/025—Rotary-piston machines or pumps of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents the moving and the stationary member having co-operating elements in spiral form

Definitions

• the field of the invention relates to scroll pumps.
• said at least one flexible member is formed of one or more materials structured such that said stiffness of said material decreases from said outer portion to said inner portion.
• the clearance distances can be controlled by controlling the difference in height of the outer member and of the flexible member, they may alternatively be formed of the same height, indeed they may be formed from a single sheet and shims may be used between the outer member and the plates to provide the low clearances required.
• the outer member and flexible member may be formed of a single sheet of material and this may be machined such that the flexible member has a different height than the outer member. Machining techniques are such that this can be done to high accuracy in a relatively straightforward manner allowing differences in heights of tens of microns to be accurately achieved. Alternatively, they may be machined to a single uniform height and shims may be used to provide the clearances between the flexible member and the plates.
• the spiral may be a circular involute.
• said driving member comprises a motor and crankshaft.
• the driving member and in particular the path of rotation that it is configured to follow can be selected such that the distance between the flexible members forming the channel can be controlled to provide an appropriate constriction.
• the distance between adjacent flexible members is small but finite such that they do not contact.
• knowledge of the stiffness of the flexible members and the size of the axial offset of the crankshaft can be used to set the distance between adjacent flexible members and thus, the size of the constriction used in the pumping to a certain value.
• the distance between adjacent flexible members is set to be between 10 and 200 microns of each other at the closest point. This sets the constriction size and affects the efficiency of the pumping.
• Figure 1 schematically shows the flexible spiral of a pump according to an embodiment
• a traditional scroll pump requires two rigid matched spirals in the form of interleaving scrolls that mesh together.
• Embodiments employ a single flexible scroll, which in some embodiments also comprises a central hub driven in an orbiting motion attached to a central portion of the flexible scroll.
• the orbiting motion has a large enough orbit to push at least some of the adjacent flexible wraps or members along the constricted radius together in phase with the offset.
• all of the flexible members or wraps are pushed together.
• flexible members are considered to be pushed together where they contact each other or are within 200 microns of each other.
• Stiff polymers e.g. polyamides
• the polymer wall could be reinforced with longitudinal fibres to resist gas pressure distortion (although this should be carefully managed as the increase in stiffness may have a detrimental effect on power requirements); or a moulded/extruded scroll form could be used where the wall has some internal hollow structure to increase buckling resistance. Dynamic behaviour and stress may dictate shaft rotational speed.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Rotary Pumps (AREA)
• Applications Or Details Of Rotary Compressors (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=65998775

Family Applications (1)

Country Status (4)

Citations (2)

Family Cites Families (6)

• 2019
  • 2019-02-15 GB GB1902135.1A patent/GB2581387B/en active Active
• 2020
  • 2020-02-13 EP EP20707775.1A patent/EP3924623B1/de active Active
  • 2020-02-13 WO PCT/GB2020/050336 patent/WO2020165590A1/en unknown
  • 2020-02-13 CN CN202080014199.7A patent/CN113396282B/zh active Active

Patent Citations (2)

Also Published As

Similar Documents

Legal Events