INTEGRATED SCREW COMPRESSOR MOTOR
A screw compressor is provided and includes a housing (11), helical screws (21, 24) disposed within the housing (11) for rotation about respective rotational axes (RA1, RA2) in a mutually engaged relationship, at least one stator (30, 40) disposed within the housing (11) about a corresponding one of the helical screws (21, 24) and a conductive element (50, 60). The conductive element (50, 60) is wound about the at least one stator (30, 40) such that current applied to the conductive element (50, 60) generates a flux field by which the corresponding one of the helical screws (21, 24) is driven to rotate about the corresponding rotational axis (RA1, RA2).
The subject matter disclosed herein relates to compressors and, more particularly, to an integrated screw compressor motor.
Rotary-screw compressors (or screw compressors, for short) typically employ rotary-type positive-displacement mechanisms and are used where large volumes of high-pressure fluid are needed for large industrial applications or to operate high-power tools. Screw compressors usually include two meshing helical screws, known as rotors, to compress a fluid. In a dry-running or oil free screw compressor, timing gears ensure that male and female rotors maintain precise alignment. In an oil-flooded screw compressor, lubricating oil bridges the space between the rotors, both providing a hydraulic seal and transferring mechanical energy between the driving and driven rotor. In any case, fluid enters screw compressors at their suction sides and moves through the threads as the screws rotate. The meshing rotors force the fluid through the compressors and the fluid exits at the end of the screws in a compressed state.
For oil free screw compressors, the male rotor is driven by a motor and a gear is attached at the opposite end. Another gear is attached to female rotor to mesh with the gear on the male rotor. The gear set maintains a clearance between the rotors and drives the female. The presence of the motor and gears and the rotor shaft extensions thus requires that one or more additional housings be added to the screw compressor housing to support and retain the motor and gears and the rotor shaft extensions. This additional housing material increases costs and leads to decreased efficiencies due to windage losses, for example.
BRIEF DESCRIPTION OF THE DISCLOSUREAccording to one aspect of the disclosure, a screw compressor is provided and includes a housing, helical screws disposed within the housing for rotation about respective rotational axes in a mutually engaged relationship, at least one stator disposed within the housing about a corresponding one of the helical screws and a conductive element. The conductive element is wound about the at least one stator such that current applied to the conductive element generates a flux field by which the corresponding one of the helical screws is driven to rotate about the corresponding rotational axis.
In accordance with additional or alternative embodiments, the helical screws and the at least one stator are laminated.
In accordance with additional or alternative embodiments, the helical screws respectively include a male helical screw and a female helical screw.
In accordance with additional or alternative embodiments, the male helical screw includes a first hub and multiple protrusions extending outwardly from the first hub in a helical formation along a length of the first hub, the female helical screw includes a second hub and multiple recess-defining protrusions extending outwardly from the second hub in a helical formation along a length of the second hub and the at least one stator includes helical teeth about which the conductive element is wound.
In accordance with additional or alternative embodiments, the conductive element extends about a partial arc-length of a circumference of the corresponding one of the helical screws.
In accordance with additional or alternative embodiments, the screw compressor further includes rotor shafts about which the helical screws are rotatable and bearings coupled to the housing to rotatably support the rotor shafts.
In accordance with additional or alternative embodiments, a controller is configured to control rotations of the helical screws such that the helical screws remain separated during rotations thereof.
In accordance with another aspect of the disclosure, a screw compressor is provided and includes a housing, first and second helical screws disposed within the housing for rotation about first and second rotational axes, respectively, in a mutually engaged relationship, first and second stators disposed within the housing about the first and second helical screws, respectively, and first and second conductive elements. The first and second conductive elements are wound about the first and second stators, respectively, such that current applied to the first and second conductive elements generates flux fields by which the first and second helical screws are driven to rotate about the first and second rotational axes, respectively.
In accordance with additional or alternative embodiments, the first and second helical screws and the first and second stators are laminated.
In accordance with additional or alternative embodiments, the first and second helical screws respectively include a male helical screw and one or more female helical screws. The male helical screw includes a first hub and multiple protrusions extending outwardly from the first hub in a helical formation along a length of the first hub and each of the one or more female helical screws includes a second hub and multiple recess-defining protrusions extending outwardly from the second hub in a helical formation along a length of the second hub.
In accordance with additional or alternative embodiments, the first and second stators include helical teeth about which the first and second conductive elements are wound.
In accordance with additional or alternative embodiments, the first conductive element extends about a partial arc-length of a circumference of the first helical screw and the second conductive element extends about a partial arc-length of a circumference of the second helical screw.
In accordance with additional or alternative embodiments, the screw compressor further includes a first rotor shaft about which the first helical screw is rotatable, first bearings coupled to the housing to rotatably support the first rotor shaft, a second rotor shaft about which the second helical screw is rotatable and second bearings coupled to the housing to rotatably support the second rotor shaft.
In accordance with additional or alternative embodiments, a controller is configured to control rotations of the first and second helical screws such that the first and second helical screws remain separated during rotations thereof.
In accordance with yet another aspect of the disclosure, a fluid system is provided. The fluid system includes an inlet, an outlet and a screw compressor fluidly interposed between the inlet and the outlet. The screw compressor includes a housing which is receptive of fluid from the inlet and which is configured to direct the fluid into the outlet, first and second helical screws disposed within the housing for rotation about first and second rotational axes, respectively, in a mutually engaged relationship to compress the fluid received from the inlet and directed into the outlet, first and second stators disposed within the housing about the first and second helical screws, respectively, and first and second conductive elements. The first and second conductive elements are wound about the first and second stators, respectively, such that current applied to the first and second conductive elements generates flux fields by which the first and second helical screws are driven to rotate about the first and second rotational axes, respectively.
In accordance with additional or alternative embodiments, the first and second helical screws and the first and second stators are laminated.
In accordance with additional or alternative embodiments, the first and second helical screws respectively include a male helical screw and one or more female helical screws. The male helical screw includes a first hub and multiple protrusions extending outwardly from the first hub in a helical formation along a length of the first hub and each of the one or more female helical screw includes a second hub and multiple recess-defining protrusions extending outwardly from the second hub in a helical formation along a length of the second hub.
In accordance with additional or alternative embodiments, the first and second stators include helical teeth about which the first and second conductive elements are wound.
In accordance with additional or alternative embodiments, the first conductive element extends about a partial arc-length of a circumference of the first helical screw and the second conductive element extends about a partial arc-length of a circumference of the second helical screw.
In accordance with additional or alternative embodiments, the screw compressor further includes a first rotor shaft about which the first helical screw is rotatable, first bearings coupled to the housing to rotatably support the first rotor shaft, a second rotor shaft about which the second helical screw is rotatable and second bearings coupled to the housing to rotatably support the second rotor shaft.
In accordance with additional or alternative embodiments, a controller is configured to control rotations of the first and second helical screws such that the first and second helical screws remain separated during rotations thereof.
These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.
The subject matter, which is regarded as the disclosure, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the disclosure are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
The detailed description explains embodiments of the disclosure, together with advantages and features, by way of example with reference to the drawings.
DETAILED DESCRIPTION OF THE DISCLOSUREAs will be described below, an oil-free screw compressor is provided within a compressor housing with a motor stator and windings that are integrated within the housing. The screw compressor thus has a compact size and operates at an increased efficiency owing to reduced windage losses.
With reference to
Although the inlet 12 and the outlet 13 are illustrated as being radially oriented relative to the compressor housing 11, it is to be understood that this is not required. For example, one or both of the inlet 12 and the outlet 13 may be axially oriented relative to the compressor housing 11 instead.
With reference to
The first and second helical screws 21 and 24 are disposed within the compressor housing 11 for rotation about the first and second rotational axes RA1 and RA2, respectively, in a mutually engaged relationship to compress the fluid received by the compressor housing 11 from the inlet 12 and directed into the outlet 13.
The screw compressor 20 also includes a first stator 30, which is integrated into the compressor housing 11, a second stator 40, which is integrated into the compressor housing 11, a first conductive element 50 and a second conductive element 60. The first conductive element 50 may be provided as insulated steel laminations with insulated metallic wire (e.g., a copper wire with insulation surrounding the copper in each winding) with windings and end turns. The windings and end turns are wound about the first stator 30 within the compressor housing 11. Similarly, the second conductive element 60 may be provided as insulated steel laminations with insulated metallic wire (e.g., a copper wire with insulation surrounding the copper in each winding) with windings and end turns. The windings and end turns are wound about the second stator 40 within the compressor housing 11. As such, current applied to the first and second conductive elements 50 and 60 generates flux fields by which the first and second helical screws 21 and 24 are driven to rotate about the first and second rotational axes RA1 and RA2, respectively.
Since the rotations of the first and second helical screws 21 and 24 are driven by the generated flux fields as described above, the fluid system 10 as a whole can be operated in an oil-free condition.
Although
With reference to
For purposes of clarity and brevity, the following description will relate to only the case of a single female helical screw 240 being provided with a single male helical screw 210.
At each axial location of the first and second helical screws 21 and 24, at least one of the multiple protrusions 212 is received within and thus engages with at least a corresponding one of the multiple recess-defining protrusions 242 to compress fluid ingested between the first and second helical screws 21 and 24 at a given moment. The first and second helical formations 213 and 243 tend to drive the fluid being compressed in an axial direction (e.g., from the inlet 12 and the first end of the compressor housing 11 to the second end of the compressor housing 11 and into the outlet 13).
With reference to
With reference to back to
With reference to
In the case of
By contrast, in the case of
As an additional feature, as shown in
As such, with additional reference back to
While the disclosure is provided in detail in connection with only a limited number of embodiments, it should be readily understood that the disclosure is not limited to such disclosed embodiments. Rather, the disclosure can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the disclosure. Additionally, while various embodiments of the disclosure have been described, it is to be understood that the exemplary embodiment(s) may include only some of the described exemplary aspects. Accordingly, the disclosure is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
Claims
1. A screw compressor, comprising:
- a housing;
- helical screws disposed within the housing for rotation about respective rotational axes in a mutually engaged relationship;
- at least one stator disposed within the housing about a corresponding one of the helical screws; and
- a conductive element wound about the at least one stator such that current applied to the conductive element generates a flux field by which the corresponding one of the helical screws is driven to rotate about the corresponding rotational axis.
2. The screw compressor according to claim 1, wherein the helical screws and the at least one stator are laminated.
3. The screw compressor according to claim 1, wherein the helical screws respectively comprise a male helical screw and a female helical screw, wherein:
- the male helical screw comprises a first hub and multiple protrusions extending outwardly from the first hub in a helical formation along a length of the first hub,
- the female helical screw comprises a second hub and multiple recess-defining protrusions extending outwardly from the second hub in a helical formation along a length of the second hub, and
- the at least one stator comprises helical teeth about which the conductive element is wound.
4. The screw compressor according to claim 1, wherein the conductive element extends about a partial arc-length of a circumference of the corresponding one of the helical screws.
5. The screw compressor according to claim 1, further comprising:
- rotor shafts about which the helical screws are rotatable; and
- bearings coupled to the housing to rotatably support the rotor shafts.
6. The screw compressor according to claim 1, further comprising a controller configured to control rotations of the helical screws such that the helical screws remain separated during rotations thereof.
7. A screw compressor, comprising:
- a housing;
- first and second helical screws disposed within the housing for rotation about first and second rotational axes, respectively, in a mutually engaged relationship;
- first and second stators disposed within the housing about the first and second helical screws, respectively; and
- first and second conductive elements wound about the first and second stators, respectively, such that current applied to the first and second conductive elements generates flux fields by which the first and second helical screws are driven to rotate about the first and second rotational axes, respectively.
8. The screw compressor according to claim 7, wherein the first and second helical screws and the first and second stators are laminated.
9. The screw compressor according to claim 7, wherein the first and second helical screws respectively comprise a male helical screw and one or more female helical screw, wherein:
- the male helical screw comprises a first hub and multiple protrusions extending outwardly from the first hub in a helical formation along a length of the first hub, and
- each of the one or more female helical screws comprises a second hub and multiple recess-defining protrusions extending outwardly from the second hub in a helical formation along a length of the second hub.
10. The screw compressor according to claim 7, wherein the first and second stators comprise helical teeth about which the first and second conductive elements are wound.
11. The screw compressor according to claim 7, wherein:
- the first conductive element extends about a partial arc-length of a circumference of the first helical screw, and
- the second conductive element extends about a partial arc-length of a circumference of the second helical screw.
12. The screw compressor according to claim 7, further comprising:
- a first rotor shaft about which the first helical screw is rotatable;
- first bearings coupled to the housing to rotatably support the first rotor shaft;
- a second rotor shaft about which the second helical screw is rotatable; and
- second bearings coupled to the housing to rotatably support the second rotor shaft.
13. The screw compressor according to claim 7, further comprising a controller configured to control rotations of the first and second helical screws such that the first and second helical screws remain separated during rotations thereof.
14. A fluid system, comprising:
- an inlet;
- an outlet; and
- a screw compressor fluidly interposed between the inlet and the outlet and comprising:
- a housing which is receptive of fluid from the inlet and which is configured to direct the fluid into the outlet;
- first and second helical screws disposed within the housing for rotation about first and second rotational axes, respectively, in a mutually engaged relationship to compress the fluid received from the inlet and directed into the outlet;
- first and second stators disposed within the housing about the first and second helical screws, respectively; and
- first and second conductive elements wound about the first and second stators, respectively, such that current applied to the first and second conductive elements generates flux fields by which the first and second helical screws are driven to rotate about the first and second rotational axes, respectively.
15. The fluid system according to claim 14, wherein the first and second helical screws and the first and second stators are laminated.
16. The fluid system according to claim 14, wherein the first and second helical screws respectively comprise a male helical screw and one or more female helical screws, wherein:
- the male helical screw comprises a first hub and multiple protrusions extending outwardly from the first hub in a helical formation along a length of the first hub, and
- each of the one or more female helical screws comprises a second hub and multiple recess-defining protrusions extending outwardly from the second hub in a helical formation along a length of the second hub.
17. The fluid system according to claim 14, wherein the first and second stators comprise helical teeth about which the first and second conductive elements are wound.
18. The fluid system according to claim 14, wherein:
- the first conductive element extends about a partial arc-length of a circumference of the first helical screw, and
- the second conductive element extends about a partial arc-length of a circumference of the second helical screw.
19. The fluid system according to claim 14, further comprising:
- a first rotor shaft about which the first helical screw is rotatable;
- first bearings coupled to the housing to rotatably support the first rotor shaft;
- a second rotor shaft about which the second helical screw is rotatable; and
- second bearings coupled to the housing to rotatably support the second rotor shaft
20. The fluid system according to claim 14, further comprising a controller configured to control rotations of the first and second helical screws such that the first and second helical screws remain separated during rotations thereof.
Type: Application
Filed: Sep 13, 2017
Publication Date: Sep 23, 2021
Inventors: Vishnu M. Sishtla (Manlius, NY), Jagadeesh Tangudu (South Windsor, CT)
Application Number: 16/330,710