CA2084878A1

CA2084878A1 - Diaphragm and piston pump

Info

Publication number: CA2084878A1
Application number: CA002084878A
Authority: CA
Inventors: Louis Van Den Bergh; Georges Verberckmoes; Werner De Jonghe
Original assignee: Individual
Current assignee: Aro Corp
Priority date: 1991-05-02
Filing date: 1992-05-01
Publication date: 1992-11-03
Also published as: WO1992019868A1; JPH06501086A; EP0537334A1

Abstract

An improved double acting diaphragm pump utilizes at least one supplemental pressure chamber (26, 34), including a supplemental piston (24) and cylinder, arranged coaxially with the connecting shaft (60) of the two diaphragms (14, 16). The supplemental chambers (26, 34) are connected via parallel pressure lines or conduits (90, 91) to the pressure source for the two diaphragms (14, 16) and associated pressure chambers (64, 76).

Description

92/19868 PCr/US9~/03~3 7 ~3 DL~PHR~GM A~-D PISTO~ PUMP

BACKGROUND OF THE I~IVE~'TlO~;

This invention relates generally to an impro~ed double acting diaphraom pump and~ more particularlv~ to a double acting diaphragm pump wherein the pumping force upon ~he fluid which is tO be pumped exceeds the force attributable to pneumatic or other fluid pressure directlv on the diaphragm. Such pumps are often called 2:1. 3:1.
etc. diaphra~m pumps.

Heretofore. a double acting diaphragm pump t~picall~ includes first and second.
main diaphragms each of which separate a pump chamber from a pressure cham~er. -The pump chamber receives the fluid or material pumped or transported and the pressure charnber receives pressurized fluid such as air that acls upon the diaphragm to effect flexure and thus pumping action. The separate diaphragms for a double actin~
diaphra~m pump are generally connected b!~ a shaft so that the diaphraPms will reciprocate in unison in a manner which alternately provides pumping of fluid from one of the pump chambers or the other. Since the two pump chambers are connectedto a common inlet manifold and a common outlet manifold. a continuous flow of fluid into the inlet manifold and from the outlet manifold is pro~ided b\ the described operation of the pump.

The force to effect the pumping action b~ such a pump is equal to the area of the diaphra m times the pressure per unit of area of the diaphraom. Thus. in a double acting diaphragm pump which provides a continuous output. the pumpine force is limited bv the area of the rnain diaphra~m.

There has, therefore. been a need to enhance the pumpinu force. Herelofore. a ~;nown double acting diaphragTn pump which provides for enhanced pumpin~ force on fluid in the pumping chamber includes a separate fluid pressure diaphraom WO 9~/19868 PCrtUS92/03~ `

.t3~3 2 mechanicall~ connected to a spaced main pumpin~ diaphra~m b~ a shafc The separate fluid pressure diaphragm has a surface area which may be equal to or ~reater than the main pumping diaphragm thus providing an increased pumpine force throu~h the mechanical shaft connection to the main pumping diaphra~m. U.S. Palent ~o.
4,83û,586, assigned to the Aro Corporation, Bryan~ Ohio ~the assignee of ~his patent application) shows such a device.

Nevertheless, there has remained a need to provide an improved diaphraem pump capable of providing enhanced pressure for pumpine fluid and impro~ed operating life particularly at hieher operating pressure.

SUMMAI~Y OF THE ]I~,'VENTIOI~

Briefly, the present invention relates to a double acting diaphragm pump of the type which includes a pair of flexible diaphragms interconnected b~ a shaf~ and operative to reciprocate in response to pressure on one or the other of the diaphraems to effect pumping through a first pumping chamber associated with one diaphragm and a second pumping chamber associated with the other diaphraem. Therebv a continuous fluid input and output is effected b! the double acting diaphra~m pump.
The invention specificall relates to the impro-ement of a supplemental pressure chamber defined, in part~ bv a piston and cylinder which provides an additive pumping force to the main diaphragm via a connected shaft means. The additive force is synchronized with the force derived from pressure on the appropriate main diaphra~m.
Such svnchronization is effected by means of a parallel fluid pressure conduit connection to the supplemental chamber and the pressure chamber. In this manner~additive force mav be provided for each of the pumping chambers. Additional supplemental chambers connected in parallel in the manner described mav provide further additive forces for pumping.

9~/19868 . P~r/l 1~9~/03~
` 7 ~

Thus. it is an object of the present invention to provide an impro~ed~ double acting, diaphragm pump comprisin~ at least one supplemental pressure housin~
including first and second supplemental fluid pressure chambers and a supplemental piston and cylinder, each of said first and second supplemental fluid pressure chambers havin~ a wall thereof defined by said supplemental piston~ said supplernental piston bein~ connected to the shaft means for movement therewith; and fluid conduit means for connecting said source nneans with said second supplemçntal fluid pressure chamber in parallel with said first pumping chamber and for connecting said source means with said first supplemental fluid pressure chamber in parallel with said second pumping charnber~ therebv effec~ing an additive pumping force associated with the supplemental piston and drivin~ said shaft means for pumpino bv said first and second pumping chambers.

The foregoing and other aspects will become apparent from the following detailed description of the invention when considered in conjunction with the accompanyin~ drawing figures.

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. . ~ .

BRlEF DESCRIPTION OF THF. DRAWll~IGS

I:ig. I is a cross sec~ l view ol all ~n~bodiltlenl ol` lhe iu~prove(l duuble acting diaphragm pump of the present invention. -DETAILED D,~CR~IPTION

The present invention is shown in a preferred embodiment in Fig. 1 and constitutes an improvernent relative to ~he construction described in U.S. Patent No.
4,830,586. The present invention thus relates to a double acting diaphragm pump. As shown in Fig. 1, the double acthIg diaphragm pump of the invention includes an inlet manifold 18 and an outlet manifold 20, and thence into one of two pumping chambers 10 or 12. Fluid frorn the chambers 10 or'I2 then flows into the outlet manifold 2~) and subsequently through outlet 50. Fluid is pumped alternatively frorn pumping chamber 10 and from pumping chamber 12. In this manner fluid is continuously pumped from the inlet 44 through the outl,et 50 as the fluid alternatively is pumped via chambers 10 and 12. A~s known to those of ordinary skill in the art, check valves 47, 49, 51 and 53 are provided at the entranee and exit of each chamber 10 and 12 tocontrol the direction of fluid flow through the chambers I0 and 12 from the inlet manifold 18 to the outlet manifold 20 as the diaphragms 14 and 16 associated with the pumping chambers flex to effect fluid flow.

The construction of each of the chambers 10 and 12 is substantially the same.
Charnber 10 is formed, in part, by a housing 52, and a flexible diaphragm 14 whieh is a main diaphragm 14 that cooperates with housing 52~ Diaphragm 14 is sandwiehed between plates 56 and 58 which connects to a shaft 22~ The shaft 22 reciprocateswithin a second housing 62~ The second housing 62 and diaphragm 14 fur~her define a pressure chamber 64. A fluid pressure conduit 66 connects from a pilot controlvalve assembly 28 to chamber 64 and provides high pressure fluid to the chamber 64 that acts against the surface area of the diaphragm 14 causing operation or flexure of .,.,~ .
-.. , ... . - . - , , . ,, , , ~ - . . . . .
.:; ~ - . . .. . :.

~ 92/198~8 Pc~/uss~ ?~

~ s~ 7 ~$
~he diaphra~m 14 and pumpino of fluid throuoh chamber ln ~l~ernatel~. condui~, 66 connects to an exhaust as controlled b~ assembl~ 28 In a similar fashion. chamber 12 is defined b~ a housino 66 and a main fle~ible diaphra~m 1$. The diaphra~m 16 is held between plates 70 and 72 which attach with the shaft 60. The shaft 60 is further retained within a housincr 74- which defines a second pressure chamber 76. A fluid conduit 69 connects to the second pressure charnber 76 bv wav of the control mechanism 2~, Conduit 69 mav also connec~ to exhaust. The chambers 64 and 76 are alternativel~ pressurized and the diaphrams ]4 and 16 alternatively flex in reciprocal fashion to cause fluid to flow into the chambers 10 and from the chambers 12 or vice versa, The operation and flow of pressure to the chambers 64 and 76 via conduits 66. 69 is effected bv the control means 2S

The improvement of the present invention constitutes the inclusion of supplemental pressure chambers 26 and 34 defined by the housinc- 62 and 74 in combination with an additional supplemental piston 2~ Piston 24 separa~es the supplemental pressure chambers 34 and 26 and is ~enerally coaxial with the chambers 10 and 12 and the shafts 60 and 22. Thus the supplemental piston 24 is sandwicl~ed between shaft 60 and adapter 8n. This assembly reciprocates in unison with the shaft 60. The direction of movement of the piston 2~ within the supplemental pressurt~charnbers 3~ and 26 is determined by the pressure actin~ on piston 24 w,hich, in turn.
is a function of control means 28 and the connection thereof throuoh appropriateconduits to chambers 34 and 26. Specifically. conduit 66 is in parallel relation with a conduit 90 to charnber 26 so that chamber 26 is pressurized simultaneousl~ with chamber 6~.

In like fashion, the chamber 34 is connected in parallel via conduit 91 with thecharnber 76. In this manner. the chambers 34 and 76 are simultaneously pressurized and the force of fluid pressure within those chambers 34 and 36 acts on the diaphra~rns 16 and throu~h the shaft 60 a~ainst fluid within the chamber 12 ., ,, ,,,, ~ . . . . .
. . ~ : , , ~ . ; . . , , ....
. . , ., . . : . . . . .
: . . ' . '' '~ . ' . ' . ':
': , :. , . '. . ' . '. '. :

WO 92/1~868 PC~ R~ 3/,~
37~, If the pis~on 24 has a surface area exactl- equal to that of the diaphragm l~.
then the total force on the fluid within the chamber 10 is rwice that of a t~pical prior art pump that does not include the piston 2~. in other words. a Iypical double ac~ing diaphragm pump. Similarly. the pressure on fluid within the chamber 1' would be doubled due ~o pressure in chambers 34 and 76.

The piston 24 is thus typically circular and concentric with the shaft 60. The shaft 60 reciprocates bacl; and forth and acts to transmit ~orce and mo~ement of the various diaphra~ms at each of the chambers 34~ 76~ 26 and ~4 are alternatel~ filled with pressurized air or fluid and connected to exhaust. ~ote that the surface area or effective surface area of the piston 24 rnay be of anv desired size in order to thereb~i control the additive force imparted to the shaft 60. For example~ the area of the piston 24 may be twice that of the area of the diaphragm 1~. Alternativel~, the area of ~he piston 24 may be one half that of the area of the diaphragm 1 l.

Also, a plurality of piston and cvlinders providing supplemental pressure ma!
be arranged along the axis of the shaft 60. That is, plura]ity of supplemental piston and cylinders and associated supplemental chambers mav be arranged in parallel ~-arrangement along the axis of the shaft 60~ each of the supplemental chambers associated with a supplemental piston and cvlinder bein~ appropriatel! connec~ed with a pressure source in parallel with the main pressure chamber tO drive the shaft 6~1 and provide pressure to the appropriate pumpin~ chamber.

Other variations of the invention are possible. Thus. while there has been sel forth a preferred embodiment of the invention~ it is to be understood thal the invention is to be limited only by the following claims and their equivalents.

::. , , . : : . . : .

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a double acting diaphragm pump of the type including first and second pumping chambers for alternately receiving and discharging a fluid which is to be pumped, said first and second pumping chambers having a wall thereof defined by first and second flexible main diaphragms, respectively, each of said first and second flexible main diaphragms having a surface for contact with said fluid, said first and second flexible main diaphragms also having another surface in communication with first and second pressure chambers, respectively, for receipt of a pressurized fluid to effect pumping, said pump further including source means for providing said pressurized fluid alternately to said first and second pressure chambers, said first and second flexible main diaphragms being mechanically connected by shaft means to thereby move in unison and reciprocate and alternately effect ingress and egress of comprising, in combination:
at least one supplemental pressure housing including first and second supplemental fluid pressure chambers and a supplemental piston and cylinder, each of said first and second supplemental fluid pressure chambers having a wall thereof defined by said supplemental piston, said supplemental piston being connected to said shaft means for movement therewith; and fluid conduit means for connecting said source means with said second supplemental fluid pressure chamber in parallel with said first pumping chamber and for connecting said source means with said first supplemental fluid pressure chamber in parallel with said second pumping chamber, to alternately supply said pressure fluid to said supplemental pressures fluid chambers, thereby effecting an additive pumping force associated with said supplemental piston and driving said shaft means for pumping by said first and second pumping chambers.

2. The improved double acting diaphragm pump of claim 1 wherein the areas of said first and second flexible main diaphragms and said supplemental piston are WO 92/19868 PCT/US?

substantially equal to provide a pumping force which is substantially double the force associated with said first and second flexible main diaphragms.

3. The improved double acting diaphragm pump of claim 1 wherein said supplemental piston has an area which is a selected multiple of the area of said first flexible main diaphragm to provide a selected pumping force.