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
  • F04B43/10—Pumps having fluid drive
  • F04B43/113—Pumps having fluid drive the actuating fluid being controlled by at least one valve
  • F04B43/1136—Pumps having fluid drive the actuating fluid being controlled by at least one valve with two or more pumping chambers in parallel
• • 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
  • F04B9/00—Piston machines or pumps characterised by the driving or driven means to or from their working members
  • F04B9/08—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid
  • F04B9/12—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being elastic, e.g. steam or air
  • F04B9/129—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being elastic, e.g. steam or air having plural pumping chambers
  • F04B9/137—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being elastic, e.g. steam or air having plural pumping chambers the pumping members not being mechanically connected to each other
  • F04B9/1372—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being elastic, e.g. steam or air having plural pumping chambers the pumping members not being mechanically connected to each other the movement of each pump piston in the two directions is obtained by a double-acting piston fluid motor

Definitions

• the present invention relates to a pump arrangement for liquids comprising at least one pair of cooperating pump chambers which, when actuated upon by a pneumatic control system, are alternately supplied with or drain ⁇ ed of the liquid being pumped, each of said chambers being connected, via an inlet branch line having a non ⁇ return valve, to a tank or the like via an inlet trunk line and, via an outlet branch line, each of which also having a non-return valve, to a common trunk outlet line, a control valve being provided to govern the filling and emptying of pneumatic control chambers related to said pump chambers.
• diaphragm pumps are generally used because they exhibit several operational advantages, primarily the fact that, when the outlet flow is shut off, the pumping pressure is maintained but the drive unit is not operating meaning that no energy is supplied to the liquid. Also as far as mechanical forces are concerned diaphragm pumps are kind to the liquids pumped. Further, such pumps are relatively insensitive to the presence of bigger par ⁇ ticles, fibres and the like in the liquid. However, on the other hand diaphragm pumps have certain operational limitations or drawbacks, especially that the outgoing flow is not constant timewise but heavily pulsating.
• the object of the invention is to provide a pump arrangement at which the above-mentioned disadvantages and limitations have been eliminated or in any case essentially reduced.
• the pump arrange ⁇ ment includes means which start the pressure stroke in the one pump chamber before the pressure stroke in the other pump chamber has ended.
• the two pump chambers must operate independently of each other.
• the invention is based on the realization that such an individual mode of operation and the corres ⁇ ponding advantages cannot be attained in prior art pump arrangements where the chambers are dependent of each other.
• diaphragm pumps the two diaphragms are mechanically interconnected and mechani ⁇ cally connected with the control valve. According to the present invention there is no such mechanical connection between the pump chambers and the control valve.
• Fig. 1 illustrates a pump arrangement having two single-acting diaphragm pumps which are not mechani ⁇ cally interconnected.
• Fig. 2 illustrates a pump arrangement having two single-acting pumps with no diaphragm or other mechani- cal partition between the control fluid and the pumped fluid.
• the pump arrangement shown in fig. 1 comprises two pump chambers 1 and 2, each having a diaphragm 3 and 4, respectively.
• the pumped liquid 8 enters through a trunk feed line 5 and continues via branch lines 6, 7 with non-return valves into the space below the dia ⁇ phragm in the related pump chamber.
• Liquid 8 exits through two branch lines 9 and 10, respectively, which are connected to a common trunk outlet line 11.
• the two diaphragm pumps are controlled by means of a pneumatic system. That system comprises a pressure source 12 connected to the inlet port of a fourway two- position valve 13, the valve body of which, shaped e.g. as a slide, is controlled by a unit 14 operating pneu ⁇ matically or electrically and governed either by a time circuit or by the pump chambers 1, 2. Above each liquid chamber there is a pneumatic compression chamber la, 2a, which via a conduit lb, 2b is connected to the valve 13. Numeral 15 designates a suction unit con ⁇ trolling the suction movement of the diaphragm in operation at a given moment. The unit has a drive means 16. If the inlet pressure in the feed line 5 is gene ⁇ rated in some other way, e.g. by a feed pump or by a positive static pressure, means 15 and 16 are not necessary.
• Fig. 1 illustrates a segment of the operational cycle during which pressurized air has been supplied to the left control chamber la from pressure source 12 and through valve 13.
• this chamber In this way there has in this chamber been built up a compression pressure which has forced diaphragm 3 downwards so that liquid is pressed out through branch line 9 having a non-return valve 17. While a portion of the downward movement of diaphragm 3 still remains, valve 13 is switched to its other posi ⁇ tion. This,starts the creation of a compression in chamber 2a.
• the air volume which is locked up in chamber la and which still is subjected to a positive pressure, will continue to press diaphragm 3 downwards.
• non-return valve is intended to cover any suitable valve capable of carrying out the function of a conventional non ⁇ return valve, e.g. a valve controlled electrically or mechanically.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Reciprocating Pumps (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20386624

Family Applications (1)

Country Status (2)

Cited By (5)

Families Citing this family (1)

Citations (5)

• 1992
  • 1992-06-26 SE SE9201981A patent/SE9201981L/ not_active Application Discontinuation
• 1993
  • 1993-06-24 WO PCT/SE1993/000571 patent/WO1994000689A1/en active Application Filing

Patent Citations (5)

Non-Patent Citations (2)

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