Housing for accommodating gearbox of rotary screw compressor

Abstract

According to one embodiment, the invention comprises a beam-shaped housing (100) for accommodating a system for transmitting torque from a drive shaft of a motor to a rotor shaft of a rotary screw compressor, the housing (100) comprising a motor opening (104) on a first side (102), and two screw openings (202, 203) on a second side (200) opposite and parallel to the first side (102), characterized in that the motor opening (104) and the screw openings (202, 203) are connected to each other by means of a coupling means (104). The housing (100) further comprises two sets of ribs (204, 205) extending between the first side (102) and the second side (200), and wherein the ends of the ribs (204, 205) on the second side (200) are radially distributed around each set of the screw openings (202, 203), and wherein each set of the ends of the ribs (204, 205) on the first side (102) converges to a point (206, 207) of the edge of the motor opening (104).

Description

Technical Field

[0001] The present invention relates to a housing for housing a mechanical system, such as a gearbox, for transmitting mechanical torque from a motor to one or more shafts of a rotary screw compressor. Background Art

[0002] A rotary screw compressor is a machine designed to produce compressed gas, such as compressed air. The compressed gas at a certain operating pressure is then used in various applications, for example, to drive other machines.

[0003] A rotary screw compressor comprises twin screws, a male rotor and a female rotor, which rotate in opposite directions as the volume between the twin screws and the housing decreases. Each screw is provided with a screw profile, and as the rotors rotate, the gas is compressed between these rotors.

[0004] In order to rotate the rotor, a drive consisting of an electric motor, a power turbine, a diesel engine or any other suitable drive is required. However, the speed at which the screw of a rotary screw compressor must rotate to achieve the desired operating pressure does not usually correspond to the speed of the drive. Nevertheless, even if the speeds match, the mechanical torque from the drive still needs to be transmitted to the screw.

[0005] In order to transmit the mechanical torque, a mechanical system configured to transmit the mechanical torque is used. The mechanical system is, for example, a set of gears that mechanically connects the shaft of the rotor to the drive.

[0006] For safety and stability, on the one hand, the mechanical system must be isolated and protected, and on the other hand, the components of the mechanical system together with the drive shaft and the rotor of the rotary screw compressor must be firmly supported.

[0007] Therefore, there is a need for a housing to safely, stably and permanently house the mechanical system for transmitting mechanical torque from a drive to a rotary screw compressor. Summary of the invention

[0008] An object of the present invention is to provide a housing for housing a mechanical system for transmitting mechanical torque from a drive to a rotary screw compressor.

[0009] According to a first aspect of the invention, this object is achieved by providing a housing according to claim 1 .

[0010] The present invention includes a generally beam-shaped housing for accommodating a mechanical system configured to transmit mechanical torque from a drive shaft of a motor to a first and / or second screw shaft of a rotary screw compressor, the housing including a motor opening on a first side adapted to insert the drive shaft, and two screw openings on a second side opposite to and parallel to the first side, each of the two screw openings being adapted to insert a first and second screw shaft, respectively, characterized in that the housing also includes first and second groups of ribs extending between the first and second sides, respectively, and wherein the ends of the ribs on the second side of each group of ribs are radially distributed around the first and second screw openings, respectively, and wherein the ends of the ribs on the first side of each group of ribs converge toward a first or second point on an edge of the motor opening, respectively.

[0011] It will be appreciated that the housing is substantially beam-shaped. A geometric beam or rectangular block is a polyhedron having six rectangular faces, eight corners and twelve sides (also referred to as ribs). The substantially beam-shaped shape of the housing means that one or more corners and / or edges may be rounded in whole or in part. Furthermore, one or more recesses and / or protrusions may also be present. Thus, deviations from the exact shape of the geometric shape are possible, wherein the skilled person clearly recognizes that the shape of the outer surface of the housing is beam-shaped.

[0012] The drive shaft originates from a drive of an electric motor, a power turbine, a diesel engine or any other engine suitable for the purpose. This drive shaft of the drive is inserted into the housing on one side of the housing, which side is the first side and is also called the motor side. On the side opposite to the motor side, the second side, the two shafts of the rotor or screw of the rotary screw compressor are located. This side is also called the compressor side.

[0013] Typically, the drive shaft will not be in axial relationship with one of the screw shafts. In addition, the screw shafts are axially parallel to each other, as is usually the case in rotary screw compressors. Furthermore, for efficient mechanical transmission, the axes of the drive shaft and the screw shaft will be perpendicular to the plane determined by the motor side and / or the compressor side. As a result, the shafts do have the same direction.

[0014] A motor opening is provided for inserting the drive shaft, while a screw opening is provided for the screw shaft. Thus, the housing has openings on two opposite sides. Furthermore, in order to accommodate the mechanical system, the housing will be partially hollow on the inside.

[0015] The housing is also characterized by an innovative concept that it includes two sets of internal ribs for rigidity and strength of the housing in order to effectively transmit torque. In the following, it will be further elucidated how these sets of ribs are constructed.

[0016] The ribs are usually made of the same material as the rest of the shell. Alternatively, they can also be made of a different material as long as these ribs can be fixedly bonded to the material constituting the shell.

[0017] Each set of ribs extends between a first and a second side, in other words between the motor side on the one hand and the compressor side on the other hand.

[0018] The ribs are substantially elongated in the direction between these aforementioned sides, wherein the cross section is substantially rectangular. The ends of the ribs are radially distributed in each group over the circumference of the two screw openings. In other words, the ends of the first group of ribs are radially distributed around the circumference of the first screw opening, and the ends of the second group of ribs are radially distributed around the circumference of the second screw opening.

[0019] Each set of ribs then extends to the motor side, wherein the ends of the ribs of each set of ribs meet or converge at each respective point adjacent to an edge of the opening.

[0020] Through the above-described construction, several advantages over the prior art can be identified.

[0021] By radially distributing the ends of the ribs around the respective screw openings, the vibrations caused by the rotating screw during operation are compensated and / or absorbed by these ribs without the forces being concentrated at a single point. In other words, the vibrations arising and distributed around the screw are absorbed by the ribs.

[0022] When the components in the housing are working, and therefore when the mechanical torque from the drive motor is transmitted to the screw via the drive shaft, most of the vibrations will originate from the rotating screw. This can be explained by the operation of the compressor compared to the operation of the drive motor. Since ambient air or other gases are compressed in the compressor, it is more dependent on external factors that may affect the operation, while the drive motor can operate more stably compared to the compressor. However, note that this depends on the drive technology used. Compared to an internal combustion engine, an electric motor will generally operate more stably.

[0023] On the motor side, the ends of the ribs converge to a point per group. The vibrations from the rotating screw can then be concentrated to a point around the motor opening per group of screws. This allows emphasis to be placed on the motor side to make the areas at and around these points strong, rigid and / or strong enough to absorb these vibrations.

[0024] Another advantage is that this configuration prevents the ribs from reaching rotating components located within the housing. The ribs can then be positioned so as not to interfere with the operation of the mechanical transmission system.

[0025] Preferably, the ribs have no sharp transitions. This has the advantage that no additional stress concentrations occur.

[0026] According to one embodiment, when mounted or placed in the screw bore, the point where the ends of the ribs of the first and second sets of ribs converge lies in a plane defined by the geometric axis of the screw shaft.

[0027] In other words, the points on the edge of the motor opening, to which the ribs converge to absorb vibrations, are located in a plane perpendicular to the plane of the motor side and, when mounted in the screw hole, are further defined by the geometric axis or diameter of the screw shaft. Vibrations generated in the axial direction of the screw shaft can thus be effectively absorbed via the ribs without re-generating imbalances. If these points were not located in the above-mentioned plane, such imbalances would occur and mechanical momentum would occur between these points and the points located on the geometric axis of the screw shaft.

[0028] According to one embodiment, the cross section of the rib increases gradually from the first side to the second side.

[0029] Thus, according to this embodiment, the cross section of the ribs will increase from points at or on the edge of the motor opening to points around the circumference of the screw opening. This creates sufficient stiffness on the side where the greatest vibrations will occur (because these vibrations are concentrated at these points), as described above.

[0030] Preferably, according to one embodiment, the edges of the rib or ribs in the longitudinal direction between the two ends will further engage on at least one side different from the motor side and / or the compressor side, preferably on both other sides.

[0031] These ribs are respectively engaged on the inner side of the housing where the motor is located and on the side where the compressor is located, or at least on the side where the drive shaft or screw shaft is located. Due to the mainly rectangular shape of the housing, at least four other sides can be distinguished inside. The ribs are then preferably also engaged on one or both other inner sides. Engagement means that the ribs are fixedly connected to the housing with the edges, for example by a casting process or welding technology, and they are integral. As a result, the vibrations are further better distributed over the housing.

[0032] Furthermore, according to one embodiment, the housing may further comprise a third set of straight ribs extending between the motor opening side or motor side and the screw opening side or compressor side on the one hand and following the direction of the side surface perpendicular to the plane of the motor side or compressor side on the other hand. These ribs then also provide sufficient rigidity in a direction perpendicular to the plane defined by the geometric axis of the screw shaft.

[0033] In addition, the housing may also include a fourth set of ribs extending between the motor side and the compressor side and perpendicular to the third set of ribs. This provides even further additional stiffness in this direction, thereby ensuring, in combination with the other third set of ribs, sufficient stiffness in each orthogonal direction of the housing. This allows efficient transmission of mechanical torque from the motor to the screw of the compressor.

[0034] Finally, the ends of the ribs of the third and / or fourth group of ribs can engage on the edge of the motor opening. Thus, the ribs extend over the entire allowed length to obtain the maximum rigidity of the housing.

[0035] According to one embodiment, the second side, thus the compressor side, also comprises a second motor opening for supporting the drive shaft. In other words, the drive shaft extends along both outer sides of the housing, wherein the drive shaft is supported on the compressor side. As a result, bending of the drive shaft in the axial direction is accommodated and thus prevented or at least reduced.

[0036] Furthermore, preferably, according to one embodiment, the motor opening on the first side is adapted to be inserted into a shroud or housing of the motor. In other words, the motor opening on the motor side is large enough to surround the housing of the motor. This allows the motor to be fixed against the housing.

[0037] According to one embodiment, the screw opening is also adapted to be inserted into the shroud or casing of the rotary screw compressor. This also allows the compressor to be permanently attached to the casing used to house the mechanical system. Together with the motor opening that houses the motor shroud, a resistance system can then be installed, allowing the transfer of mechanical torque to occur efficiently.

[0038] According to a second aspect of the present invention, a substantially beam-shaped housing for housing a mechanical system according to the first aspect of the present invention is disclosed, the housing being obtained by permanent molding techniques and / or lost molding techniques.

[0039] The housing is then constructed from a single piece consisting of cast steel or cast iron and molded into the desired shape as described above.

[0040] According to a third aspect, a compressor unit is disclosed comprising a motor and a rotary screw compressor and further comprising a housing according to the first aspect of the invention for transmitting mechanical torque from a drive shaft of the motor to a first and / or second screw shaft of the rotary screw compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The present invention will be further described with reference to the accompanying drawings, in which:

[0042] Figure 1 A front view of a motor side according to an embodiment of the present invention is shown;

[0043] Figure 2 shows a front view of a compressor side according to an embodiment of the present invention;

[0044] Figure 3 shows a side view of a housing according to an embodiment of the present invention;

[0045] Figure 4 A view showing the interior of a housing at the motor side according to an embodiment of the present invention;

[0046] Figure 5 A view showing the interior of a housing at the compressor side according to an embodiment of the present invention;

[0047] Figure 6 shows a three-dimensional side view of a compressor side according to an embodiment of the present invention; and

[0048] Figure 7 A three-dimensional side view of a motor side according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0049] The present invention will be described with reference to certain embodiments and with reference to certain drawings, but the invention is not limited thereto but only by the claims. The drawings described are only schematic and non-restrictive. In the drawings, for illustrative purposes, the dimensions of certain elements may be exaggerated and not drawn to scale. The dimensions and relative dimensions do not necessarily correspond to actual embodiments of the invention.

[0050] In addition, the terms first, second, third, etc. are used in the specification and claims to distinguish similar elements without necessarily describing a sequential order or a temporal order. These terms are interchangeable under appropriate circumstances, and the embodiments of the invention may be used in a sequence other than that described or illustrated herein.

[0051] In addition, the terms top side, bottom side, above, below, etc. in the specification and claims are used for descriptive purposes and not necessarily to describe relative positions. The terms so used are interchangeable under appropriate circumstances, and the embodiments of the invention described herein can be used in orientations other than those described or shown herein.

[0052] Furthermore, although referred to as "preferred embodiments," the various embodiments should be construed as exemplary embodiments in which the invention may be practiced, rather than limitations on the scope of the invention.

[0053] The term "comprising" used in the claims should not be interpreted as being limited to the means or steps set forth below; the term does not exclude other elements or steps. The term should be interpreted as specifying the presence of the specified features, elements, steps or components mentioned, but does not exclude the presence or addition of one or more other features, elements, steps or components or combinations thereof. Therefore, the scope of the expression "a device comprising means A and B" should not be limited to a device consisting of only components A and B. The meaning is that, for the present invention, only components A and B of the device are listed, and the claims should also be interpreted as including equivalents of these components.

[0054] The housing shown in the figure is a housing for housing a mechanical system for transmitting mechanical torque from a drive shaft of a motor to a rotary screw compressor.

[0055] Figure 1 1 is a view of a motor side 102 of a housing 100 according to an embodiment of the present invention. The housing 100 is primarily beam-shaped, wherein one or more corners may be rounded, such as corner 101. On the motor side 102 of the housing 100, there is a circular 103 motor opening 104 adapted to accommodate a drive shaft and a shroud of the motor.

[0056] Through the motor opening 104 there is a view of the interior of the housing discussed in the following figures.

[0057] Figure 2 The same housing 100 is shown, but from the viewpoint of the compressor side 200. On this side 200, an opening 201 is also provided for supporting the drive shaft of the motor. Figure 1 The motor opening 104 is also visible in the middle. Both openings 104, 201 are formed by a circle 103, wherein the center of the motor opening 104 coincides axially with the center of the opening for the drive shaft 201. In other words, when the circles forming the openings 104, 201 are projected onto each other, their respective centers coincide.

[0058] exist Figure 2 On the compressor side 200 shown, two openings 202, 203 are also shown to be provided to connect and accommodate the screw of the rotary screw compressor. The shapes of these openings 202, 203 are not circular, but are suitable for the specific shape of the rotary screw compressor, and are particularly suitable for its screw.

[0059] Through these openings 202, 203, ribs 205 and 204 are visible, respectively, starting from the compressor side 200 to the motor side 102, each group 205, 204 converging to a respective point 207 and 206. The points 206 and 207 are therefore located on the edge 103 of the motor opening 104. In other words, the ribs 204, 205 extend between the motor side 102 and the compressor side 200, wherein on the compressor side 200 the ends are distributed on the edge of the respective openings 202 and 203 and converge towards the points 207 and 206, respectively.

[0060] This group of ribs 205, 204 is Figure 4 It is further shown in Figure 4 A view of the interior of the housing 100 on the motor side 102 is shown. This view corresponds to Figure 3 4-5, which shows a side view of the housing 100.

[0061] exist Figure 3 It can be further seen that at the opening 201 for the drive shaft, a protrusion 301 is provided to support the drive shaft.

[0062] Figure 5 The interior is also shown, but from the opposite perspective, ie from the compressor side 200, so that Figure 3 The section VV shown in FIG.

[0063] exist Figure 4 , the ribs 204, 205 on this side engage at points 206, 207 on the edge of the motor opening 104. In other words, each set of ribs 204, 205 engages at a common point 206, 207 on the edge of the motor opening 104.

[0064] On the other hand, Figure 5 As shown, the ends are distributed on the edges of the screw openings 202 and 203. For the rib group indicated by reference numeral 204, they engage at points 503-505, and for the rib group indicated by reference numeral 205, they engage with points 500-502.

[0065] Furthermore, the housing 100 may comprise a set of straight ribs on the inside, which extend between the motor side 102 and the compressor side 200 on the one hand and according to the direction of the side faces of the housing 100 on the other hand. Figure 4 and Figure 5 In addition, perpendicular to these straight ribs 400-404, a fourth group of ribs can be provided. Figure 4 and Figure 5 The middle part is indicated by ribs 510-511.

[0066] According to one embodiment, this vertical direction of the straight ribs may be partially deviated, as shown by rib 404. Furthermore, additional ribs may be provided to strengthen the housing, but it will also be understood that these are optional, whereby it is the set of ribs 204 and 205 that provide effective mechanical torque transfer from the drive shaft of the motor to the first and / or second screw shaft of the rotary screw compressor according to the innovative aspects of the present invention.

[0067] at last, Figure 6 and Figure 7 A three-dimensional side view of the housing 100 is shown, viewed from the direction of the compressor side 200 and the motor side 102, respectively. On the compressor side 200, a point 207 can be seen through the screw opening, to which the group of ribs 205 converge. In addition, the ribs 204 extending between the compressor side 200 and the motor side 102 are visible. In addition, the opening 201 for supporting the drive shaft of the motor is shown again. Figure 7 , the opening 201 is also shown, this time from the perspective of the motor side 102 .

Claims

1. A beam-shaped housing (100) configured to accommodate a mechanical system configured to transmit mechanical torque from a drive shaft of a motor to a first and / or second screw shaft of a rotary screw compressor, the housing (100) comprising a motor opening (104) on a first side (102) adapted for insertion of the drive shaft, and two screw openings (202, 203) on a second side (200) opposite and parallel to the first side (102), the two screw openings (202, 203) each being adapted for insertion of the first and second screw shafts, respectively, Features The housing (100) further comprises a first set of ribs (204) and a second set of ribs (205) extending between the first side (102) and the second side (200), respectively, and wherein the ends of the ribs on the second side (200) in each set of ribs (204, 205) are radially distributed around the first screw opening (500-502) and the second screw opening (503-505), respectively, and wherein the ends of the ribs on the first side in each set of ribs converge to a first point (206) and a second point (207) on the edge of the motor opening (104), respectively.

2. The housing (100) according to claim 1, wherein: When attached, the points (206, 207) to which the ends of the first set of ribs (204) and the second set of ribs (205), respectively, converge lie in a plane defined by the geometric axis of the screw shaft.

3. The housing (100) according to any one of the preceding claims, wherein The cross-section of the ribs (204, 205) gradually increases from the first side (102) to the second side (200).

4. The housing (100) according to any one of the preceding claims, wherein The edge of the rib along the longitudinal direction between the two ends is joined on at least one side different from the first side (102) or the second side (200).

5. The housing (100) according to any of the preceding claims, further comprising a third group of straight ribs (400-404), the third group of straight ribs extending between the first side (102) and the second side (200) on the one hand, and extending in the direction of a side portion of the substantially beam-shaped housing (100) on the other hand, the side portion being perpendicular to a plane defined by the first side (102) or the second side (200).

6. The housing (100) according to claim 5, further comprising a fourth group of straight ribs (510-511), wherein the fourth group of straight ribs extend between the first side (101) and the second side (200) on the one hand, and extend in a direction perpendicular to the direction of the third group of straight ribs (400-404) on the other hand.

7. The housing (100) according to claim 6, wherein: The end of one or more ribs of the third group of ribs (400-404) and / or the fourth group of ribs (510-511) engages at a point on the edge of the motor opening (104).

8. The housing (100) according to any one of the preceding claims, further comprising a second motor opening (201) on the second side (200), the second motor opening being adapted to support the drive shaft.

9. The housing (100) according to any one of the preceding claims, wherein The motor opening (104) on the first side (102) is also suitable for inserting a shroud of the motor.

10. The housing (100) according to any one of the preceding claims, wherein The screw openings (202, 203) are also suitable for inserting a shroud of the rotary screw compressor.

11. A substantially beam-shaped housing (100) according to any one of the preceding claims for housing a mechanical system, the substantially beam-shaped housing being obtained by permanent moulding techniques and / or lost moulding techniques.

12. A compressor unit comprising a motor and a rotary screw compressor, and further comprising a housing (100) according to any one of the preceding claims, configured to transmit mechanical torque from a drive shaft of the motor to a first and / or second screw shaft of the rotary screw compressor.

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