US 5,291,951 AGranted

Compressed air foam pump apparatus

AssigneeUtah La Grange, Inc.

InventorJames W. Morand

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Abstract

Fire fighting apparatus for generating air compressed foam having both a water and a surfactant metering device for dispensing controlled and discrete quantities of both into a mixing conduit where they combine into a foam solution. The foam solution is combined with air prior to being injected within a compression chamber of an air compressor device. Foam is generated by compression of the air-foam solution and then is discharged through a discharge device. The air compression device is also controlled to dispense a discrete quantity of foam therefrom in correlation with the discrete quantities dispensed from the other two metering devices. The quantitative dispensing coordination of the air compression device with the two metering devices makes all three devices both relational and proportional in the cooperative generation of compressed air foam, and thus ensures prompt production of constant quality foam. The relational and proportional condition is achieved in a preferred mechanical embodiment by incorporating a common, concentric drive shaft driving all three dispensing devices, each of which is a rotary vane pump. In an electrical embodiment, the relational and proportional condition is achieved by an electric drive motor driving each dispensing device at a pre-set R.P.M., each motor being, connected to and controlled by a programmable control device Mechanical and electrical embodiments have devices for monitoring and controlling a variety of operational parameters to further enable prompt production of constant quality air compressed foam.

Claims38

Dependent claims

A compressed air foam pump apparatus comprising:

(a) a drive means for cyclically driving a power transmission means;
(b) a means for delivering a fluid from a fluid source to a first fluid conduit;
(c) a first metering means, driven by said power transmission means, for metering a predetermined volume of said fluid with each cycle of said power transmission means, and comprising:
a first meter injection port, in fluid communication with the first fluid conduit, for introducing said fluid to the first metering means;
a first meter discharge port;
and
a second fluid conduit in fluid communication with the first meter discharge port, into which said predetermined volume of fluid is discharged from the first metering means;
(d) a second metering means, driven by said power transmission means, for metering a predetermined volume of a foaming agent surfactant from a foaming agent surfactant source with each cycle of the power transmission means, and comprising:
a second meter injection port;
a foaming agent conduit, in fluid communication with both the second meter injection port and the foaming agent surfactant source, for introducing said foaming agent surfactant to the second metering means;
and
a second meter discharge port, in fluid communication with said second fluid conduit, through which said predetermined volume of foaming agent surfactant is discharged into said second fluid conduit,
whereby said discharged predetermined volumes of foaming agent surfactant and fluid are mixed within said second fluid conduit to produce a foam solution mixture;
(e) an air compressor means, driven by said power transmission means, for metering, mixing, compressing and discharging both a predetermined volume of said foam solution mixture and a predetermined volume of air with each cycle of said power transmission means to produce an air-foam mixture, the air compressor means comprising:
at least one air inlet port for supplying air to the air compressor means;
a compressor injection port in fluid communication with said second fluid conduit for delivering said foam solution mixture to the air compressor means;
and
a compressor discharge port through which the air-foam mixture is discharged from the air compressor means,
a portion of said second fluid conduit comprising a heat sink that is in contact with said air compressor means, whereby heat generated by said air compressor means is transferred to the foam solution mixture within said second fluid conduit.

16 more elements

A compressed air foam pump apparatus comprising:

(a) means for delivering a fluid from a fluid source to a first fluid conduit;
(b) first and second metering means, each being operable at a plurality of metering speeds, for respectively metering therefrom said fluid and a foaming agent surfactant proportional to the respective metering speeds thereof,
said first metering means comprising:
a first meter injection port, in fluid communication with the first fluid conduit, for introducing said fluid to the first metering means;
a first meter discharge port;
and
a second fluid conduit, in fluid communication with the first meter discharge port, into which said predetermined volume of fluid is discharged from the first metering means;
(c) a foaming agent conduit, in fluid communication with both a second meter injection port and a foaming agent surfactant source,
(d) said second metering means comprising:
the second meter injection port in fluid communication with the foaming agent conduit, for introducing said foaming agent surfactant to the second metering means;
and
a second meter discharge port, in fluid communication with said second fluid conduit, through which said foaming agent surfactant is discharged into said second fluid conduit,
whereby both said foaming agent surfactant and said fluid discharged within said second fluid conduit are mixed therein to produce a foam solution mixture;
(e) an air conduit, in fluid communication with both the second fluid conduit and an air source,
(f) an air compressor means, operable at a plurality of metering speeds, for metering, mixing, compressing and discharging therefrom, proportional to the metering speed thereof, both air and said foam solution mixture to produce an air-foam mixture, the air compressor means comprising:
a compressor injection port in fluid communication with said second fluid conduit for receiving therefrom both said foam solution mixture and said air to the air compressor means;
and
a compressor discharge port for discharging therefrom said produced air-foam mixture;
(g) first, second, and third drive means for respectively driving the first and second metering means and the air compressor means, the respective operating speed of the first and second metering means and the air compressor means being proportional to respective electrical first, second and third motor drive signals supplied thereto;
and
(h) programmable control means comprising a program memory means, electrically connected to the first, the second and the third drive means, for independently setting the respective operating speeds of the first and second metering means and the air compressor means by respectively generating said first, second and third motor drive signals according to a preprogrammed instruction set stored in said programmable memory means.

18 more elements

A method for producing a compressed air foam comprising the steps of:

(a) driving a power transmission means cyclically with a drive means;
(b) driving first and second metering means and an air compressor means, each respectively having an injection port and a discharge port, with said cyclically driven power transmission means;
(c) supplying a fluid from a fluid source to a first fluid conduit;
(d) metering a predetermined volume of said fluid in the first fluid conduit through said injection port of said first metering means with each cycle of said power transmission means;
(e) discharging said predetermined volume of said fluid from said discharge port of said first meter means into a second fluid conduit with each cycle of said power transmission means;
(f) supplying a foaming agent surfactant from a foaming agent surfactant source to a foaming agent surfactant conduit;
(g) metering a predetermined volume of said foaming agent surfactant in the foaming agent surfactant conduit through said injection port of said second metering means with each cycle of said power transmission means;
(h) discharging said predetermined volume of said foaming agent surfactant from said discharge port of said second metering means into said second fluid conduit with each cycle of said power transmission means, whereby both said discharged predetermined volumes of foaming agent surfactant and fluid are mixed within said second fluid conduit to produce therein a foam solution mixture;
(i) supplying air to said injection port of said air compressor means;
(j) supplying foam solution mixture in said second fluid conduit to a portion of said second fluid conduit comprising a heat sink that is in contact with said air compressor means, whereby heat generated by said air compressor means is transferred to the foam solution mixture within said second fluid conduit;
(k) supplying foam solution from said heat sink to said injection port of said air compressor means;
(l) metering both a predetermined volume of air and a predetermined volume of said foam solution mixture into said injection port of said air compressor means with each cycle of said power transmission means;
(m) mixing and compressing both said predetermined volume of air and said predetermined volume of said foam solution mixture within said air compressor means to produce and air-foam mixture;
and
(n) discharging said air-foam mixture from said discharge port of said air compressor means with each cycle of said power transmission means.

12 more elements

A method for producing a compressed air foam comprising the steps of:

(a) driving first and second metering means and an air compressor means, each respectively having an injection port and a discharge port, respectively with first, second, and third drive means, the respective operating speed of the first, second, and third drive means being proportional to respective electrical first, second, and third motor drive signals supplied thereto;
(b) monitoring and controlling said first, second and third drive means with a programmable control means comprising a program memory means, electrically connected to the first, second and third drive means, for independently setting the operating speeds thereof by respectively generating said first, second and third motor drive signals according to a preprogrammed instruction set stored in said program memory means;
(c) supplying a fluid from a fluid source to a first fluid conduit;
(d) metering a predetermined volume of said fluid in the first fluid conduit through said injection port of said first metering means;
(e) discharging said predetermined volume of said fluid from said discharge port of said first meter means into a second fluid conduit;
(f) supplying a foaming agent surfactant from a foaming agent surfactant source to a foaming agent surfactant conduit;
(g) metering a predetermined volume of said foaming agent surfactant in the foaming agent surfactant conduit through said injection port of said second metering means;
(h) discharging said predetermined volumes of said foaming agent surfactant from said discharge port of said second metering means into said second fluid conduit, whereby both said discharged predetermined volumes of foaming agent surfactant and fluid are mixed within said second fluid conduit to produce therein a foam solution mixture;
(i) supplying air to said injection port of said air compressor means;
(j) supplying foam solution mixture in said second fluid conduit to said injection port of said air compressor means;
(k) metering both a predetermined volume of air and a predetermined volume of said foam solution mixture into said injection port of said air compressor means;
(l) mixing and compressing both said predetermined volume of air and said predetermined volume of said foam solution mixture within said air compressor means to produce an air-foam mixture;
and
(m) discharging said air-foam mixture from said discharge port of said air compressor means.

11 more elements

Dependencies are inferred from the claim text.