US5494262A — Metal delivery system

Claim 1

Independent Claim 147 words

Apparatus for delivering molten metal to a reservoir comprising: a variable speed pump for molten metal a delivery pipe leading from said pump, said delivery pipe having an upwardly extending portion above said pump which leads to a discharge orifice from which molten metal may be intermittently discharged into said receiver, a variable speed motor for driving said pump, and a controller for said motor causing said motor to drive said pump essentially continuously and selectively at a first speed sufficient to raise molten metal to and maintain it at a level in said upwardly extending portion of said delivery pipe below said discharge orifice and at a second increased speed sufficient to force molten metal in said delivery pipe from said discharge orifice into the receiver, whereby molten metal is intermittently discharged from said discharge orifice when the pump is driven at the second increased speed.

Claim 2

Dependent Claim 147 words

Apparatus for delivering molten metal to a reservoir comprising: a variable speed pump for molten metal a delivery pipe leading from said pump, said delivery pipe having an upwardly extending portion above said pump which leads to a discharge orifice from which molten metal may be intermittently discharged into said receiver, a variable speed motor for driving said pump, and a controller for said motor causing said motor to drive said pump essentially continuously and selectively at a first speed sufficient to raise molten metal to and maintain it at a level in said upwardly extending portion of said delivery pipe below said discharge orifice and at a second increased speed sufficient to force molten metal in said delivery pipe from said discharge orifice into the receiver, whereby molten metal is intermittently discharged from said discharge orifice when the pump is driven at the second increased speed.

Claim 3

Dependent Claim 38 words

Apparatus as defined in claim 1, wherein said controller includes a timer for regulating the duration of time of operation of said pump at said second speed and hence the amount of molten metal discharged from said orifice.

Claim 4

Dependent Claim 18 words

Apparatus as defined in claim 1, wherein said upwardly extending portion of said delivery pipe is disposed vertically.

Claim 5

Dependent Claim 34 words

Apparatus as defined in claim 1, and further comprising a housing above the receiver defining a chamber into which said orifice extends, and a dispense pipe leading downward from said chamber to the receiver.

Claim 6

Dependent Claim 13 words

Apparatus as defined in claim 1, wherein said pump is an impeller pump.

Claim 7

Dependent Claim 13 words

Apparatus as defined in claim 1, wherein said pump is a gear pump.

Claim 8

Dependent Claim 13 words

Apparatus as defined in claim 1, wherein said pump is a vane pump.

Claim 9

Dependent Claim 39 words

Apparatus as defined in claim 2, and further including a reservoir for molten metal, said variable speed pump being disposed in said reservoir and adapted to be immersed in molten metal therein, and said pump is an impeller pump.

Claim 10

Dependent Claim 59 words

Apparatus as defined in claim 8, wherein said pump has an impeller having a central axis and is supported for rotation about said central axis, said impeller having impeller arms extending generally radially outwardly from said central axis, said arms having passages for molten metal provided with inlets adjacent said central axis and outlets at their radially outer extremities.

Claim 11

Dependent Claim 57 words

Apparatus as defined in claim 2, and further comprising a housing above the receiver defining a chamber into which said orifice extends, and a dispense pipe leading downward from said chamber to the receiver, said orifice discharging upwardly, and a deflector above said orifice for deflecting molten metal discharged from said orifice downwardly into said dispense pipe.

Claim 12

Dependent Claim 18 words

Apparatus as defined in claim 10, wherein said upwardly extending portion of said delivery pipe is disposed vertically.

Claim 13

Dependent Claim 23 words

Apparatus as defined in claim 11, and further including a heater for heating said delivery pipe, and heat insulation covering said delivery pipe.

Claim 14

Dependent Claim 28 words

Apparatus as defined in claim 12, and further including a heat containment box enclosing said housing and at least portions of said delivery pipe and said dispense pipe.

Claim 15

Dependent Claim 31 words

Apparatus as defined in claim 13, and further including means for supplying an inert gas to said chamber to protect the molten metal from at least one of oxidation and contamination.

Claim 16

Dependent Claim 79 words

Apparatus as defined in claim 14, wherein said reservoir is an open top container disposed in a tank containing a reserve supply of the molten metal, piping for molten metal leading from said tank to said reservoir, and a power device for moving molten metal through said piping to said reservoir, said reservoir having an upper edge providing a dam to prevent overfilling of said reservoir and permit return of excess molten metal from said reservoir to said tank.

Claim 17

Dependent Claim 21 words

Apparatus as defined in claim 15, wherein said power device comprises a pump submerged in the molten metal in said tank.

Claim 18

Dependent Claim 18 words

Apparatus as defined in claim 15 wherein said power device comprises an impeller in said variable speed pump.

Claim 19

Independent Claim 117 words

A method of delivering molten metal to a receiver through a delivery pipe having an upwardly extending section leading to a discharge orifice, comprising providing a variable speed pump for forcing molten metal through said delivery pipe, operating the pump essentially continuously, operating said pump at a first speed sufficient to raise molten metal to a level in said upwardly extending section of said delivery pipe below said discharge orifice and to maintain the molten metal at said level before discharge of molten metal from said discharge orifice, and thereafter operating said pump at a second speed, greater than the first speed and sufficient to force molten metal above said level and discharge it from said orifice.

Claim 20

Independent Claim 117 words

A method of delivering molten metal to a receiver through a delivery pipe having an upwardly extending section leading to a discharge orifice, comprising providing a variable speed pump for forcing molten metal through said delivery pipe, operating the pump essentially continuously, operating said pump at a first speed sufficient to raise molten metal to a level in said upwardly extending section of said delivery pipe below said discharge orifice and to maintain the molten metal at said level before discharge of molten metal from said discharge orifice, and thereafter operating said pump at a second speed, greater than the first speed and sufficient to force molten metal above said level and discharge it from said orifice.

Claim 21

Dependent Claim 36 words

The method as defined in claim 18 in which a timer controls the length of time of operation of the pump at the second speed to control the amount of molten metal discharged from the orifice.

Claim 22

Dependent Claim 19 words

The method as defined in claim 18 wherein the upwardly extending portion of the delivery pipe is disposed vertically.

Claim 23

Dependent Claim 29 words

The method as defined in claim 18 wherein the orifice discharges metal into a chamber and the metal passes from the chamber through a dispense tube to the receiver.

Claim 24

Dependent Claim 14 words

The method as defined in claim 18 wherein the pump is an impeller pump.

Claim 25

Dependent Claim 14 words

The method as defined in claim 18 wherein the pump is a gear pump.

Claim 26

Dependent Claim 14 words

The method as defined in claim 18 wherein the pump is a vane pump.

Claim 27

Dependent Claim 37 words

The method as defined in claim 18 wherein molten metal is discharged from the orifice generally upwardly into a chamber and the molten metal passes from the chamber generally downwardly through a dispense pipe to the receiver.

Claim 28

Dependent Claim 30 words

The method as defined in claim 25 which also comprises applying an inert gas to the chamber to protect the molten metal from at least one of oxidation and contamination.

Claim 29

Dependent Claim 34 words

The method as defined in claim 18 wherein molten metal is discharged from the orifice generally upwardly into a chamber and is deflected generally downwardly and passes through a dispense pipe to the receiver.

Claim 30

Dependent Claim 63 words

The method as defined in claim 18 wherein the pump is operated alternately at the first speed and the second speed to intermittently discharge molten metal from the orifice whenever the pump is operating at the second speed and to quickly cease the discharge of molten metal from the orifice when the speed rapidly changes from the second speed to the first speed.

Claim 31

Dependent Claim 67 words

The method as defined in claim 18 wherein the pump is immersed in molten metal received in an open top container which is disposed in a tank containing a reserve supply of molten metal with the container having a dam adjacent the top of the container to prevent overfilling of the container and permit the return of any excess molten metal from the container to the tank.

Claim 32

Dependent Claim 32 words

The method as defined in claim 29 which also comprises pumping sufficient molten metal from the tank into the container to insure that the pump remains immersed in molten metal while operating.

Claim 33

Dependent Claim 55 words

The method as defined in claim 30 which also comprises disposing the dam in a chamber through which excess molten metal can flow from the container to the tank and supplying an inert gas to the chamber while the pump is operating to protect the molten metal from at least one of oxidation and contamination.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1999-02-26	1999-08-28	2000-02-27	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2003-02-26	2003-08-28	2004-02-27	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2007-02-26	2007-08-28	2008-02-27	$7700.00	Window Closed / Lapsed

Metal delivery system

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag