Method and device for casting a rotor of a compressor, vacuum pump and/or expander device with a longitudinal axis

Patent metadata

Field	Value
Publication number	US-11673189-B2
Application number	US-202017431514-A
Country	US
Kind code	B2
Filing date	Mar 3, 2020
Priority date	Apr 9, 2019
Publication date	Jun 13, 2023
Grant date	Jun 13, 2023

Abstract

The device according to any of the preceding claims 13 to 19, characterized in that the device is further configured to carry out a method comprising the step of positioning the green sand mold ( 3 ), wherein the device is provided with levelling means configured to hold an upper side of the green sand mold ( 3 ) during step c in a parallel position in relation to a gravitationally horizontal plane.

First claim

The invention claimed is:

1. A method for casting a rotor ( 2 ) with a longitudinal axis ( 15 ) for a compressor, vacuum pump and/or expander device,
wherein the method comprises the following steps:
a. the formation of a green sand mold ( 3 ) with a cavity ( 4 ), wherein the cavity ( 4 ) is configured to contain a core ( 5 ) with a mold cavity ( 6 ), wherein a surface of the mold cavity ( 6 ) is configured to form the rotor ( 2 ) in such a way that a longitudinal axis of the mold cavity ( 6 ) coincides with the longitudinal axis ( 15 ) of the rotor ( 2 ) formed in the mold cavity( 6 );
b. inserting the core ( 5 ) into the cavity ( 4 ); and
c. pouring molten casting material into the mold cavity ( 6 ) through an inlet ( 7 ) of the core ( 5 ), and filling the mold cavity ( 6 ) completely or almost completely with casting material to form the rotor ( 2 ),

wherein,
the cavity ( 4 ) is held in a tilted position by tilting means ( 16 ) during step c, with the longitudinal axis of the mold cavity ( 6 ) tilted in relation to a gravitationally vertical direction and in relation to a gravitationally horizontal plane.

2. The method according to claim 1 , wherein during step c the longitudinal axis of the mold cavity ( 6 ) is tilted in relation to a gravitationally horizontal plane over an angle of at least 5°.

3. The method according to claim 1 , wherein during step c the longitudinal axis of the mold cavity ( 6 ) is tilted in relation to a gravitationally horizontal plane over an angle of at most 45°.

4. The method according to claim 1 , wherein the cavity ( 4 ) is held in the tilted position during step c in such a way that in relation to the inlet ( 7 ) the mold cavity ( 6 ) extends upwards with respect to the gravitationally vertical direction.

5. The method according to claim 1 , wherein during step c the angle over which the longitudinal axis of the mold cavity ( 6 ) is tilted in relation to a gravitationally vertical direction and in relation to a gravitationally horizontal plane is fixed by blocking means.

6. The method according to claim 1 , wherein the cavity ( 4 ) is held in the aforementioned tilted position during step b.

7. The method according to claim 6 , wherein the cavity ( 4 ) is formed during step a in the aforementioned tilted position in the green sand mold ( 3 ).

8. The method according to claim 1 , wherein the green sand mold ( 3 ) with the cavity ( 4 ) is formed during step a by casting and pressing green sand on a mold plate ( 18 ), which the mold plate ( 18 ) is provided with a protruding pattern ( 19 ) configured to form the cavity ( 4 ) in the green sand mold ( 3 ).

9. The method according to claim 8 , wherein the mold plate ( 18 ) comprises several flat plates tilted in relation to each other, at least one of these flat plates being provided with the protruding pattern ( 19 ) and tilted in relation to a gravitationally horizontal plane at an angle corresponding to the aforementioned tilted position.

10. The method according to claim 1 , wherein the method is carried out on an automatic mold line.

11. The method according to claim 1 , wherein before step c the molten casting material is filtered through a metal filter ( 17 ).

12. The method according to claim 1 , wherein the method further comprises the step of positioning the green sand mold ( 3 ), whereby an upper side of the green sand mold ( 3 ) is held during step c by levelling means in a parallel position with a gravitationally horizontal plane.

13. A device for casting a rotor ( 2 ) with a longitudinal axis ( 15 ) for a compressor, vacuum pump and/or expander device,
wherein the device has been configured to perform a method that comprises the following steps:
a. the formation of a green sand mold ( 3 ) with a cavity ( 4 ), wherein the cavity ( 4 ) is configured to contain a core ( 5 ) with a mold cavity ( 6 ), wherein a surface of the mold cavity ( 6 ) is configured to form the rotor ( 2 ) in such a way that a longitudinal axis of the mold cavity ( 6 ) coincides with the longitudinal axis ( 15 ) of the rotor ( 2 ) formed in the mold cavity( 6 );
b. inserting the core ( 5 ) into the cavity ( 4 ); and
c. pouring molten casting material into the mold cavity ( 6 ) through an inlet ( 7 ) of the core ( 5 ), and filling the mold cavity ( 6 ) completely or almost completely with casting material to form the rotor ( 2 ),

wherein the device comprises the green sand mold with the cavity and
the device is provided with tilting means ( 16 ) configured to hold the cavity ( 4 ) in a tilted position during step c with the longitudinal axis of the mold cavity ( 6 ) in relation to a gravitationally vertical direction and in relation to a gravitationally horizontal plane.

14. The device according to claim 13 , wherein the device is provided with blocking means in order to fix, during step c, the angle over which the longitudinal axis of the mold cavity ( 6 ) is tilted in relation to a gravitationally vertical direction and in relation to a gravitationally horizontal plane.

15. The device according to claim 13 , wherein the device is configured to hold the cavity ( 4 ) in the aforementioned tilted position during step b and that the cavity ( 4 ) is formed during step a in the aforementioned tilted position in the green sand mold ( 3 ).

16. The device according to claim 13 , wherein the device is configured in such a way that the green sand mold ( 3 ) with the cavity ( 4 ) is formed during step a by casting and pressing green sand on a mold plate ( 18 ), which the mold plate ( 18 ) is provided with a protruding pattern ( 19 ) configured to form the cavity ( 4 ) in the green sand mold ( 3 ).

17. The device according to claim 16 , wherein the mold plate ( 18 ) comprises several flat plates tilted in relation to each other, at least one of these flat plates being provided with the protruding pattern ( 19 ) and tilted in relation to a gravitationally horizontal plane at an angle corresponding to the aforementioned tilted position.

18. The device according to claim 13 , wherein the device is carried out as an automatic mold line.

19. The device according to claim 13 , wherein the device is provided with a metal filter ( 17 ) configured to filter the molten casting material before step c.

20. The device according to claim 13 , wherein the device is further configured to carry out a method comprising the step of positioning the green sand mold ( 3 ), wherein the device is provided with levelling means configured to hold an upper side of the green sand mold ( 3 ) during step c in a parallel position in relation to a gravitationally horizontal plane.

Assignees

• Atlas Copco Airpower Nv

Inventors

• Adriaens Victor
• Wang Jun
• De Backer Jan

Classifications

• B22C9/088

  Feeder heads · CPC title

• B22C9/22 Primary

  Moulds for peculiarly-shaped castings · CPC title

• B22C21/00

  Flasks; Accessories therefor (stripping plates B22C17/06) · CPC title

• B22C9/086

  Filters · CPC title

• B22D45/00 Primary

  Equipment for casting, not otherwise provided for · CPC title