US3881846A

US3881846A - Fluid pump with resilient pumping membrane

Info

Publication number: US3881846A
Application number: US385853A
Authority: US
Inventors: Gerald E Kashmerick
Original assignee: Outboard Marine Corp
Current assignee: Outboard Marine Corp
Priority date: 1973-08-06
Filing date: 1973-08-06
Publication date: 1975-05-06
Anticipated expiration: 1992-05-06
Also published as: JPS5044505A; JPS587836B2; CA1005276A

Abstract

Disclosed herein is a fluid pump comprising a housing having therein a pocket, a pumping membrane of resilient material and including therein a pumping cavity located in the housing pocket, together with one-way fluid inlet and outlet valves connected to the opposite ends of the pumping membrane and means for periodically squeezing the pumping cavity within the pocket so as to reduce the volume of the cavity and thereafter permitting expansion of the cavity to thereby induce fluid flow from the membrane through the outlet valve in response to squeezing of the cavity and to induce fluid into the cavity through the inlet valve in response to expansion of the cavity.

Description

United States Patent 11 1 1111 3,881,846 Kashmerick 1 May 6, 1975 1 FLUID PUMP WITH RESILIENT PUMPING 1,503,660 2/1970 Germany 418/48 MEMBRANE 597,046 1/1948 United Kingdom 417/478 FOREIGN PATENTS OR APPLICATIONS France 417/475 Primary Examiner-William L.. Freeh Assistant Examiner-Richard E. Gluck Attorney, Agent, or FirmMichael, Best & Friedrich [57] ABSTRACT Disclosed herein is a fluid pump comprising a housing having therein a pocket, a pumping membrane of resilient material and including therein a pumping cavity located in the housing pocket, together with one-way fluid inlet and outlet valves connected to the opposite ends of the pumping membrane and means for periodically squeezing the pumping cavity within the pocket so as to reduce the volume of the cavity and thereafter permitting expansion of the cavity to thereby induce fluid flow from the membrane through the outlet valve in response to squeezing of the cavity and to induce fluid into the cavity through the inlet valve in response to expansion of the cavity,

4 Claims, 4 Drawing Figures FLUID PUMP WITH RESILIENT PUMPING MEMBRANE BACKGROUND OF THE INVENTION The invention relates generally to pumps and more particularly to pumps including a resilient membrane containing the fluid being pumped.

Most prior pumps include rubbing contact between the surfaces which contact the fluid being pumped and are accordingly subject to high wear and heat genera tion when operating dry and have a low tolerability for pumping abrasive fluids i.e., for instance, sandy fluids. In addition, such pumps provide poor suction characteristics especially when started in a dry condition.

SUMMARY OF THE INVENTION The invention provides a fluid pump including a housing having therein a pocket, a pumping membrane or member of resilient material located in the housing pocket and including therein a pumping cavity, a oneway fluid inlet valve connected to one end of the pumping cavity, a one-way outlet fluid valve connected to the other end of the pumping cavity, and means for periodically squeezing the membrane within the pocket so as to reduce the volume of the cavity and thereafter permitting expansion of the cavity to thereby induce fluid outflow from the cavity through the outlet valve in response to squeezing of the membrane and to induce fluid inflow into the cavity through the inlet valve in response to expansion of the cavity.

In further accordance with the invention, the housing includes a plurality of inwardly open pockets arranged in a circular array, the membrane includes a like plurality of cavities located in the pockets, and a series of inlet and outlet valves are provided, one inlet and one outlet valve for each cavity. In addition, the means for periodically squeezing the membrane and thereafter permitting expansion of the cavities comprises a drive shaft extending through the housing in concentric relation to the array of pockets, a cylindrical cam element mounted on the drive shaft in excentric relation thereto and for common rotation therewith, a bearing located on the outer surface of the cam element, and a hollow cylindrical member including an outer surface bonded to the membrane and an inner surface in engagement with the bearing.

One of the principal features of the invention is the provision of a fluid pump in which there is no rubbing between fluid contacting components.

Another of the principal features of the invention is the provision of a fluid pump having dry suction ability.

Still another of the principal features of the invention is the provision of a fluid pump which provides pumping action without encountering high wear and heat generation when started dry and without experiencing high wear when pumping abrasive liquids.

Still another of the principal features of the invention is the provision of a fluid pump including a pumping membrane which is constructed of resilient material, such as rubber. and which includes a plurality of elongated cavities extending between one-way inlet and outlet valves and which are periodically squeezed in the direction transverse to the elongation of the cavities and then released to effect flow through the cavities from the inlet valves and out the outlet valves.

Other features and advantages of the invention will become known by reference to the following drawings,

FIG. 1 is a diametrical sectional view of a fluid pump in accordance with the invention.

FIG. 2 is a sectional view taken along line 22 of FIG. 1.

FIG. 3 is a sectional view taken along line 3-3 of FIG. I.

FIG. 4 is a sectional view taken-along line 4-4 of FIG. 1.

Before explaining the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purposes of description and should not be regarded as limiting.

GENERAL DESCRIPTION Shown in the drawings is a fluid pump 11 which em' bodies the invention, which includes a housing 13 having therein a pocket 15, a pumping membrane 17 of resilient material having a pumping cavity 19 located in the housing pocket 15, a one-way fluid inlet valve 2l connected to the pumping cavity 19, a one-way fluid outlet valve 23 connected to pumping cavity 19, and

means for periodically squeezing the membrane within the pocket 15 to reduce the volume of the cavity 19 and thereafter permitting expansion of the cavity 19 so as to thereby induce fluid outflow from the cavity 19 through the outlet valve 23 in response to the squeezing of the membrane and to induce fluid flow into the eavity 19 through the inlet valve 21 in response to expansion of the cavity 19.

More particularly, in the illustrated construction, the housing 13 is formed of two sections or

members

29 and 31 and includes a generally cylindrical outer sur-' face 33 and a central part or portion 35 with an inner surface defining a series of elongated, radially inwardly open pockets 15 arranged in a. generally evenly spaced, circular array. Any number and form'of pockets can be employed. In the illustrated construction, six generally which are preferably circular and which are aligned with and communicate with the pockets 15.

As will be more fully appreciated hereinafter, the end of the housing 13 shown to the: left in FIG. 1 is provided with a housing end member or cover 41 including an axially inwardly opening, fluid outlet manifold passage 43 communicating with the adjacent series of openings 37 and with an outlet (not shown) adapted to communicate with exterior piping.

At its other or right end as shown in FIG. 1, the housing 13 is provided with a valve retainer 51 which includes a series of counterbored openings 53 in alignment with and communicating with the adjacent series of openings 37 in the adjacent housing end, together with an axially outwardly open, common fluid inlet passage 55 which communicates with the openings 53 and has an inlet (not shown) adapted to be connected to a source of fluid to be pumped. Covering the axially outwardly open inlet passage 55 is a housing end member or cover 57.

' The

housing sections

29 and 31, valve retainer 51,

' 'wardly from the cylindrical inner portion 61 and which each contain an elongated axially extending pumping cavity 19. At each end of the membrane 17, the cavities 19are open and there is provided (see FIG. 1) a lip or flange 65 which, at the end of the housing shown to the I left in FIG. 1, is retained between the cover 41 and the housing section 29, and which, at the right end of the housing 13, isretained between the housing section 31 and the valve retainer 51. Accordingly, the pumping membrane 17 is generally fixed relative to the housing 13. i

' JAs already indicated, the membrane 17 is formed of 'resilient material and each cavity 19 is inherently biased to a maximum volume such that the associated @porjection 63 of volume is greater than the volume of the'associated pocket 15. Of course, the number of cavities 19 corresponds to the number of housing pockets 15 and there is included a separate inlet and outlet -valve for each cavity.

Preferably, one of the series of outlet valves 23 and i 1 the series ofinlet valves 21 is formed integrally with the -pumping membrane 17 and the other series is formed as one piece member 71 which is adapted to interflt with the adjacent end of the pumping membrane 17. In

. .the illustrated construction, the series of outlet valves 23 is constructed integrally with the pumping membrane 17 and each outlet valve 23 comprises an op- I posed pair of lips 75 which are biased into engagement 3 with each other and arranged solely to permit fluid outflow from the associated cavity 19 in response to a greater pressure condition in the associated cavity than in the fluid outlet passage 43.

As can be seen from FIG. 1, the intake valve member 71 interfits or nests with the adjacent end of the pumping membrane 71 and is retained in position by the valve retainer 51.

The inlet valve member 71 is made of resilient material and each inlet valve 21 comprises an opposed pair of lips 77 which extend into the adjacent end of the associated cavity 19 and which are biased toward closed position and arranged solely to permit fluid inflow into the associated cavity from the inlet passage 55 in response to a pressure condition in the cavity less than in the inlet passage 55.

In the illustrated construction, the means for squeezing the pumping membrane 17 to periodically reduce the volume of the cavities 19 and permitting expansion of the cavities to induce flow therethrough comprises a drive shaft 81 which extends centrally through the housing 13 and is supported by suitable bearings 83 and 85. Excentrically mounted on the shaft 81 interiorly of the housing 13 and for common rotation therewith is a generally cylindrical cam element 87 having an outer surface engaging a bearing assembly 89. In turn, the bearing assembly 89 is in engagement with the inner surface of a rigid hollow cylindrical member 91 having an outer surface bonded to the cylindrical portion 61 of the pumping membrane 17. As a consequence, rotation of the drive shaft 81 causes rotating oscilation and consequent deformation of the pumping membrane 17 to press or squeeze the cavities 19 in the pockets 15 on one side of the housing 13 to thereby expell fluid from the squeezed cavities, while the diametrically opposite cavities are permitted to resiliently expand within the pockets 15 on the opposite side of the housing and thereby to induce inflow of fluid into the expanding cavities. 9

Various of the features of the invention are set forth in the following claims: v

1. A fluid pump comprising a hollow housing including means defining a series of radially inwardly open, elongated pockets arranged in a circular array with the axis of said array being generally parallel with the elongation of said pockets, a pumping membrane of resilient material including a series of elongated pumping cavities respectively located in saidhousingvpockets, a series of one-way inlet valves respectively connected with said pumping cavities, a series of one-way outlet valves respectively connected with said pumping cavities, rotary means located within said housing in excentric relation to said array of pockets for periodically squeezing said membrane within said pockets to reduce the volume of said cavities and thereafter-permitting resilient expansion of said cavities within said pockets so as thereby to induce fluid outflow from said cavities through said outlet valves in response to squeezing of said membrane and to induce fluid inflow into said cavities through said inlet valves in response to said resilient expansion of said cavities.

2. A fluid pump in accordance with claim 1 wherein said rotary means comprises a drive shaft extending through said housing in concentric relation to said array of pockets, a cylindrical cam element mounted on said drive shaft in excentric relation thereto and for common rotation therewith and including an outer surface, a bearing engaged with said outer surface of said cam element, and a hollow cylindrical member including an outer surface bonded to said membrane and an inner surface in engagement with saidbearing.

3. A fluid pump in accordance withclaim 1 wherein one of said series of inlet valves and said series of outlet valves is formed in a common member located at one end of said membrane and including a fluid passage communicating with said one seriesof valves.

4. A fluid pump in accordance with claim 1 wherein one of said series of inlet valves and said series of outlet valves is formed integrally with said membrane adjacent to one end thereof and communicates with a com-

Claims

1. A fluid pump comprising a hollow housing including means defining a series of radially inwardly open, elongated pockets arranged in a circular array with the axis of said array being generally paRallel with the elongation of said pockets, a pumping membrane of resilient material including a series of elongated pumping cavities respectively located in said housing pockets, a series of one-way inlet valves respectively connected with said pumping cavities, a series of one-way outlet valves respectively connected with said pumping cavities, rotary means located within said housing in excentric relation to said array of pockets for periodically squeezing said membrane within said pockets to reduce the volume of said cavities and thereafter permitting resilient expansion of said cavities within said pockets so as thereby to induce fluid outflow from said cavities through said outlet valves in response to squeezing of said membrane and to induce fluid inflow into said cavities through said inlet valves in response to said resilient expansion of said cavities.

2. A fluid pump in accordance with claim 1 wherein said rotary means comprises a drive shaft extending through said housing in concentric relation to said array of pockets, a cylindrical cam element mounted on said drive shaft in excentric relation thereto and for common rotation therewith and including an outer surface, a bearing engaged with said outer surface of said cam element, and a hollow cylindrical member including an outer surface bonded to said membrane and an inner surface in engagement with said bearing.

3. A fluid pump in accordance with claim 1 wherein one of said series of inlet valves and said series of outlet valves is formed in a common member located at one end of said membrane and including a fluid passage communicating with said one series of valves.

4. A fluid pump in accordance with claim 1 wherein one of said series of inlet valves and said series of outlet valves is formed integrally with said membrane adjacent to one end thereof and communicates with a common fluid passage.