Multi functional pump for pumping molten metal

• US 7,507,365 B2
• Filed: 03/02/2006
• Issued: 03/24/2009
• Est. Priority Date: 03/07/2005
• Status: Active Grant

• Current Assignee: Bruno H. Thut
• Original Assignee: Bruno H. Thut
• Inventors: Thut, Bruno H.
• Primary Examiner(s): KASTLER, SCOTT R
• Application Number:
  US11/366,138
• Publication Number:
  US 20060198725A1
• Time in Patent Office: 1,118 Days
• Field of Search: 266/235, 266/239, 266/217
• US Class Current: 266/235
• CPC Class Codes: F04D 15/0027 Varying behaviour or the very pump F04D15/0055 and F04D29/46 take precedence
• CPC Class Codes: F04D 15/0072 Installation or systems with two or more pumps, wherein the flow path through the stages can be changed, e.g. series-parallel
• CPC Class Codes: F04D 29/042 Axially shiftable rotors F04D29/041 takes precedence ; control by creating a by-pass F04D15/0027
• CPC Class Codes: F04D 7/065 for liquid metal

Abstract

The present invention features a multi-functional pump for pumping molten metal, which includes a base that is submerged in molten metal having at least two impeller chambers. The base includes one or more inlet openings and one or more outlet openings. Each outlet opening leads from one of the impeller chambers. The invention enables the impeller to be moved to a position to rotate in either impeller chamber or while straddling impeller chambers. This enables the pump to have the versatility to operate in a circulation mode; a transfer mode; two or more circulation modes; two or more transfer modes; and a combination of transfer and circulation modes. The impeller chambers can be stacked over each other and the impeller can be moved vertically in and between impeller chambers. Inventive vaned or barrel type impellers can be used to facilitate pumping while straddling impeller chambers, in view of an elongated bearing member on the impeller that maintains position relative to a bearing ring attached to the base or an inlet protector sleeve. The multifunctional pump of the invention enables infinite adjustment of the impeller using a programmable logic controller that results in positioning of the impeller at any of various locations in the base to achieve any desired output. The inventive pump is ideally suited for use in die casting and scrap submergence applications. Also featured is a method of operating the multifunctional pump of the present invention.

Claims

1. A pump for pumping molten metal, comprising:

a base including

a first impeller chamber and a second impeller chamber,

a base inlet opening in fluid communication with at least one of said first impeller chamber and said second impeller chamber, and

a first base outlet opening extending from said first impeller chamber and a second base outlet opening extending from said second impeller chamber;

a pump shaft;

a motor adapted to rotate said shaft;

an impeller fastened to said shaft and adapted to be rotated in said first impeller chamber and said second impeller chamber, said impeller including end portions spaced apart from each other along a rotational axis of said impeller, an impeller inlet opening disposed near one of said end portions and impeller outlet openings disposed near a side of said impeller, said impeller inlet opening being in fluid communication with said impeller outlet openings; and

impeller positioning means for moving said impeller in said base effective to place said impeller outlet openings so as to selectively release molten metal into said first base outlet opening or said second base outlet opening.

2. The pump of claim 1 wherein said impeller positioning means moves said impeller to place said impeller outlet openings so as to selectively release molten metal into one of said first base outlet opening and said second base outlet opening while minimizing release of molten metal into the other of said first base outlet opening and said second base outlet opening.

3. The pump of claim 1 wherein said impeller positioning means moves said impeller effective to position said impeller outlet openings effective to release molten metal simultaneously into both said first base outlet opening and said second base outlet opening.

4. The pump of claim 1 wherein said impeller positioning means moves said impeller effective to position said impeller outlet openings so as to selectively release molten metal into one of said first base outlet opening and said second base outlet opening while minimizing release of molten metal into the other of said first base outlet opening and said second base outlet opening;

and

wherein said impeller positioning means moves said impeller effective to position said impeller outlet openings effective to release molten metal simultaneously into both said first base outlet opening and said second base outlet opening.

5. The pump of claim 1 wherein said first impeller chamber and said second impeller chamber are stacked relative to each other.

6. The pump of claim 1 further comprising an outlet conduit in contact with said base and in fluid communication with one of said first base outlet opening and said second base outlet opening, wherein the other of said first base outlet opening and said second base outlet opening is a discharge passageway that extends to an outlet opening formed in an exterior surface of said base.

7. The pump of claim 1 wherein at least one of said first impeller chamber and said second impeller chamber includes a wall forming a volute.

8. The pump of claim 1 comprising a third impeller chamber and a third base outlet opening, said base inlet opening and said third base outlet opening being in fluid communication with said third impeller chamber.

9. The pump of claim 1 wherein said impeller is a single intake impeller.

10. The pump of claim 1 wherein said impeller is a dual intake impeller.

11. The pump of claim 10 wherein said impeller includes an imperforate baffle extending between end faces of the impeller transverse to the rotational axis.

12. The pump of claim 10 wherein a plurality of said impeller inlet openings are located at both end portions of the impeller and said impeller outlet openings are in fluid communication with said impeller inlet openings at both end portions of the impeller.

13. The pump of claim 11 wherein said impeller includes an upper end face and a lower end face, upper vanes disposed between said baffle and said upper end face and lower vanes disposed between said baffle and said lower end face, a plurality of upper said inlet openings located in said upper end face and a plurality of lower said inlet openings located in said lower end face, first passages in fluid communication with said upper inlet openings and said outlet openings, and second passages in fluid communication with said lower inlet openings and said outlet openings, said baffle preventing fluid communication between said first passages and said second passages.

14. The pump of claim 1 wherein said impeller is a vaned impeller formed of refractory material comprising

a central hub portion centered around a rotational axis of the impeller;

a first end plate disposed at one end of the impeller and extending transverse to said axis;

a second end plate disposed at an opposite end of the impeller and extending transverse to said axis;

an imperforate baffle plate extending transverse to said axis and located between said first end plate and said second end plate;

first vanes extending outwardly from said hub between said first end plate and said baffle plate; and

second vanes extending outwardly from said hub between said second end plate and said baffle plate;

wherein said first end plate includes a plurality of said inlet openings leading to cavities between said first vanes that form said outlet openings and said second end plate includes a plurality of said inlet openings leading to cavities between said second vanes that form said outlet openings.

15. The pump of claim 1 wherein said impeller is a barrel impeller formed of refractory material comprising

a generally cylindrical body including a central rotational axis, a first end face disposed at one end of the body and extending transverse to the axis, a second end face disposed at an opposite end of the body and extending transverse to the axis, and a side wall extending between said first end face and said second end face along the axis, said inlet openings being located in said first end face and said second end face and said outlet openings being located in said side wall;

an imperforate baffle portion of said body extending transverse to said axis and located between said first end face and said second end face;

a plurality of first passages extending from said inlet openings in said first end face to said outlet openings;

a plurality of second passages extending from said inlet openings in said second end face to said outlet openings; and

wherein said baffle portion is located between said first passages and said second passages at said side wall and is effective to prevent fluid communication between said first passages and said second passages.

16. The pump of claim 1 wherein said impeller is a vaned impeller formed of refractory material comprising

a central hub portion centered around a rotational axis of the impeller;

a first end face located at one end of the impeller and extending transverse to the axis;

a second end face disposed at an opposite end of the impeller and extending transverse to said axis;

vanes extending outwardly from said hub between said first end face and said second end face; and

wherein said first end face includes a plurality of first said inlet openings and said second end face includes a plurality of second said inlet openings, cavities are formed between said vanes that form said outlet openings, and a plurality of first passages extend from said first inlet openings to said cavities and a plurality of second passages extend from said second inlet openings to said cavities.

17. The pump of claim 16 wherein said impeller includes a first shoulder located between said vanes and said first end face of the impeller along the rotational axis and a second shoulder located between said vanes said second end face along the rotational axis, a first bearing ring member affixed on said first shoulder and a second bearing ring member affixed on said second shoulder, said first bearing ring member and said second bearing ring member being composed of impact resistant refractory material, one of said first and second bearing ring members extending for at least ⅓

of a distance between said first end face and said second end face along the rotational axis.

18. The pump of claim 17 wherein said one bearing ring member comprises a plurality of bearing rings.

19. A pump for pumping molten metal, comprising:

a base including

a first impeller chamber and a second impeller chamber stacked over one another,

a base inlet opening in fluid communication with at least one of said first impeller chamber and said second impeller chamber, and

a first base outlet opening extending from said first impeller chamber and a second base outlet opening extending from said second impeller chamber;

a pump shaft;

a motor adapted to rotate said shaft;

an impeller fastened to said shaft and adapted to be rotated in said first impeller chamber or said second impeller chamber, said impeller including end portions spaced apart from each other along a rotational axis of said impeller, an impeller inlet opening disposed near one of said end portions and impeller outlet openings disposed near a side of said impeller, said impeller inlet opening being in fluid communication with said impeller outlet openings;

impeller positioning means for vertically moving said impeller in said base effective to position said impeller outlet openings in a first position to release molten metal into said first base outlet opening or for vertically moving said impeller in said base effective to position said impeller outlet openings in a second position to release molten metal into said second base outlet opening; and

wherein said impeller positioning means vertically moves said impeller in said base effective to position said impeller outlet openings in a straddle position between said first position and said second position effective to release molten metal simultaneously into both said first base outlet opening and said second base outlet opening.

20. The pump of claim 19 wherein said impeller positioning means is adapted to move said impeller in said straddle position to position said impeller outlet openings to any of a plurality of locations between said first position and said second position.

21. A pump for pumping molten metal, comprising:

a base adapted to be submerged in molten metal, including impeller chambers stacked over each other,

a base inlet opening, and

a base outlet opening,

said base inlet opening being in fluid communication with at least one of said impeller chambers and said base outlet opening extending toward an exterior surface of said base;

a pump shaft;

an impeller connected to said pump shaft and adapted to be rotated in said impeller chambers;

a motor including a drive shaft that is rotated by said motor;

a coupling between said drive shaft and an upper portion of said pump shaft adapted to enable movement of said pump shaft to vertical positions and rotation of said pump shaft at each of said positions; and

an actuator adapted to vertically move said impeller in selected said impeller chambers while said coupling maintains engagement between said pump shaft and said drive shaft.

22. A pump for pumping molten metal, comprising:

a base including

a first impeller chamber and a second impeller chamber stacked over one another,

a base inlet opening in fluid communication with at least one of said first impeller chamber and said second impeller chamber, and

a first base outlet opening extending from said first impeller chamber and a second base outlet opening extending from said second impeller chamber;

a pump shaft having a rotational axis;

a support located above said base;

a motor mounted onto said support and including a drive shaft that is rotatably driven by said motor;

a spline shaft coupled to said drive shaft, said spline shaft including vertically extending splines around a periphery thereof;

a spline sleeve that extends around the periphery of said spline shaft, said spline sleeve including vertically extending splines around an interior surface thereof that engage said splines of said spline shaft;

a shaft coupling that affixes said pump shaft to said spline sleeve;

a bearing member disposed around said spline sleeve adapted to transmit and receive axial rotational forces along the rotational axis and radial rotational forces transverse to the rotational axis;

a support arm that engages said bearing member;

an impeller fastened to said pump shaft and adapted to be rotated in said first impeller chamber or said second impeller chamber; and

an actuator for moving said support arm up and down so as to impart vertical motion to said pump shaft effective to position said impeller in a first position to release molten metal into said first base outlet opening or in a second position to release molten metal into said second base outlet opening.

23. The pump of claim 22 wherein said actuator is adapted to move said support arm up and down so as to impart vertical motion to said pump shaft effective to position said impeller in a straddle position between said first position and said second position effective to release molten metal simultaneously into both of said first base outlet opening and said second base outlet opening.

24. The pump of claim 22 comprising two of said arms that flank said spline sleeve, each said arm including a pin that engages said bearing member.

25. The pump of claim 22 wherein said actuator includes a cylinder and a piston rod that is moved by pressurized fluid into and out of said cylinder, said piston rod being connected to said support arm.

26. The pump of claim 25 comprising a programmable logic controller adapted to send signals that enable said actuator to move said piston rod into and out of said cylinder to one or more selected positions.

27. The pump of claim 22 wherein said actuator includes a housing and a screw that can rotate in said housing, said screw being connected to said support arm.

28. The pump of claim 27 comprising a programmable logic controller adapted to send signals that enable said actuator to rotate said screw effective to move said arm to one or more selected vertical positions.

29. The pump of claim 22 comprising a programmable logic controller adapted to send signals that enable said actuator to move said support arm up and down to one or more selected positions and to receive feedback signals that correspond to the position of said arm.

30. An impeller formed of refractory material comprising:

a first end face located at one end of the impeller and extending transverse to a rotational axis of the impeller;

a second end face disposed at an opposite end of the impeller and extending transverse to the rotational axis, said impeller having a length between said first end face and said second end face along the rotational axis;

a plurality of inlet openings located in at least one of said first end face and said second end face;

outlet openings located at a side of the impeller;

a plurality of passages extending from said inlet openings toward said outlet openings;

a first shoulder located between said outlet openings and said first end face along the rotational axis and a second shoulder located between said outlet openings and said second end face along the rotational axis;

a first bearing ring member affixed on said first shoulder and a second bearing ring member affixed on said second shoulder, said first bearing ring member and said second bearing ring member being composed of impact resistant refractory material, one of said first bearing ring member and said second bearing ring member extending along the rotational axis for at least ⅓

of said length of the impeller.

31. The impeller of claim 30 comprising:

a central hub portion centered around the rotational axis;

vanes extending outwardly from said hub portion between said first end face and said second end face and cavities formed between said vanes;

a plurality of first said inlet openings located in said first end face and a plurality of second said inlet openings located in said second end face; and

said passages extending from said first inlet openings and said second inlet openings to said cavities.

32. The impeller of claim 30 wherein said one bearing ring member comprises a plurality of separate bearing rings.

33. The impeller of claim 30 comprising:

a cylindrical body having the central rotational axis and a side surface extending around a periphery of the body;

the first end face located at one end of the body and the second end face disposed at an opposite end of the body and extending transverse to the rotational axis, a plurality of first said inlet openings located in said first end face and a plurality of second said inlet openings located in said second end face;

a plurality of said outlet openings located in said side surface; and

said passages extending from said first inlet openings and said second inlet openings to said outlet openings.