Air suction orifice adjusting block of double-screw compressor and double-screw compressor thereof

Abstract

The invention discloses an air suction orifice adjusting block of a double-screw compressor and the double-screw compressor. The left side of the outer contour line of the air suction orifice adjusting block comprises a curve section AB and an arc section BC, the right side comprises a curve section FE and an arc section ED, and the lower side comprises a curve section CD. The curve section AB and the arc section BC are sequentially connected from top to bottom, the starting angle a2s of the end point B is that the # imgabs 0 # curve section FE and the arc section ED are sequentially connected from top to bottom, and the starting angle a1s of the end point F meets the condition that the shape of the # imgabs 1 # curve section CD is the same as that of a meshing line of the long edge of a female rotor tooth and the long edge of a male rotor tooth. For the female rotor and the male rotor of which the spiral parts are truncated, the negative influence caused by deviation of the air suction hole can be eliminated.

Description

Technical Field

[0001] The present invention relates to screw compressor technology. Background Art

[0002] Process screw compressors have been used in more and more working conditions due to their good dynamic balance and few wearing parts. In order to maintain good load characteristics and reduce vibration, one of the important principles for selecting process screw compressors is that the internal and external pressure ratio must match.

[0003] Since there is a simple exponential relationship between the pressure ratio (Pi) and the volume ratio (Vi), and they correspond one-to-one to the specific shapes of the suction and exhaust ports on the casting, the pressure ratio matching of the process screw compressor is usually achieved by designing the corresponding exhaust port shape. Generally, a newly developed model will be designed with 2 to 3 exhaust port shapes, corresponding to only 2 to 3 volume ratios, which can no longer meet the increasingly complex field application requirements.

[0004] For screw compressors with fixed exhaust port shapes, there is a linear proportional relationship between the internal volume ratio and the rotor length, and the internal volume ratio of the compressor can be changed by shortening the length of the spiral portion (i.e., the threaded section) of the rotor pair. The prior art adjusts the internal volume ratio by changing the length of the spiral portion of the rotor pair without changing the exhaust port shape, thereby widening the range of the internal volume ratio adjustment on the existing models.

[0005] The prior art solves the problems of increased number of molds, long design cycle, high development cost, etc. caused by the re-addition of exhaust ports. However, it faces a technical defect that the length of the spiral part of the female and male rotors is shortened from L0 to L. Accordingly, the torsion angle of the male rotor changes from τ0 to τ, and the change is a linear relationship, that is: The end position of the air intake port determined by the torsion angle τ is offset from the existing design, which results in the inability to fully utilize the rotor tooth space, the deviation of the internal volume from the ideal value, and the poor stability of the unit operation. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a suction orifice adjustment block for a twin-screw compressor, which can correct the end position of the suction orifice for the female and male rotors with shortened spiral parts and eliminate the adverse effects caused by the displacement of the suction orifice.

[0007] An embodiment of the present invention provides an air intake orifice adjustment block of a twin-screw compressor, wherein the twin-screw compressor comprises a male rotor and a female rotor, wherein the lengths of the spiral parts of the male rotor and the female rotor are truncated; the characteristic of the present invention is that the left side of the outer contour line of the air intake orifice adjustment block comprises a curve segment AB and an arc segment BC, the right side of the outer contour line of the air intake orifice adjustment block comprises a curve segment FE and an arc segment ED, and the lower side of the outer contour line of the air intake orifice adjustment block comprises a curve segment CD; the curve segment AB and the arc segment BC are sequentially connected from top to bottom, the shape of the curve segment AB is the same as the shape of the short side of any tooth of the female rotor, and the shape of the arc segment BC is the same as the arc segment of the female rotor tooth root circle adjacent to the short side of any tooth of the female rotor; the starting angle a of the endpoint B of the curve segment AB is 2s for: Among them, a 1s is the starting angle of the endpoint F of the curve segment FE, z1 is the number of teeth of the male rotor, z2 is the number of teeth of the female rotor, and the starting angle of the endpoint B refers to the angle formed by the line connecting the endpoint B and the center of the arc segment BC and the line connecting the center of the arc segment BC and the center of the arc segment ED; the curve segment FE and the arc segment ED are connected in sequence from top to bottom, the shape of the curve segment FE is the same as the shape of the long side of any tooth of the male rotor, and the shape of the arc segment ED is the same as the arc segment of the male rotor tooth root circle adjacent to the long side of any tooth of the male rotor; the starting angle a of the endpoint F of the curve segment FE is 1s satisfy: Among them, τ is the torsion angle of the truncated male rotor, a 1s0 and τ0 are respectively the suction end angle and the torsion angle when the male rotor is not truncated; the starting angle of the endpoint F refers to the angle formed by the line connecting the endpoint F and the center of the arc segment ED and the line connecting the center of the arc segment ED and the center of the arc segment BC; the curve segment CD connects the arc segment BC and the arc segment ED, and the shape of the curve segment CD is the same as the shape of the meshing line of the long side of the female rotor tooth and the long side of the male rotor tooth.

[0008] An embodiment of the present invention also discloses a twin-screw compressor, including an intake end seat, a cylinder body, a male rotor, a female rotor and the above-mentioned intake orifice adjustment block, wherein the intake end seat is connected to the cylinder body, the intake end seat is provided with an intake orifice which penetrates axially, and the intake orifice adjustment block is detachably connected to the end surface of the intake end seat facing the cylinder body; the center of the arc segment BC is located on the central axis of the female rotor, the center of the arc segment ED is located on the central axis of the male rotor, and points D and C are located on the line connecting the axis center of the female rotor and the axis center of the male rotor.

[0009] The present invention has at least the following advantages:

[0010] 1. The suction orifice adjustment block of the embodiment of the present invention can ensure that the suction end position of the twin-screw compressor is accurately matched with the cut rotor, ensuring that the screw rotor tooth grooves are fully inflated and the internal volume ratio and pressure ratio are accurately matched;

[0011] 2. The use of the suction orifice regulating block of the embodiment of the present invention avoids additional leakage caused by the failure of the suction orifice to be closed in time, reduces the fluctuation of the medium quality in the compression chamber, thereby improving the compression efficiency and reducing the air flow pulsation. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A schematic front view of a suction port adjustment block according to an embodiment of the present invention.

[0013] Figure 2 A schematic side view of a suction orifice adjustment block according to an embodiment of the present invention is shown.

[0014] Figure 3 A schematic diagram showing the meshing lines of the long sides of the female rotor teeth and the long sides of the male rotor teeth of a twin-screw compressor.

[0015] Figure 4 A schematic diagram showing a suction port adjustment block installed on a suction end seat of a twin-screw compressor according to an embodiment of the present invention is shown.

[0016] Figure 5 A partial structural schematic diagram of a twin-screw compressor equipped with a suction port adjustment block according to an embodiment of the present invention is shown.

[0017] Figure 6 A schematic diagram of a series of suction orifice adjustment blocks is shown. DETAILED DESCRIPTION

[0018] Please refer to Figure 1 and Figure 2 . The suction orifice adjustment block 100 according to one embodiment of the present invention is applied to a twin-screw compressor in which the length of the spiral parts of the male rotor and the female rotor are truncated, and the length of the spiral parts of the male rotor and the female rotor after truncating is L (the length of the spiral parts of the female and male rotors when not truncated is L0). The thickness s of the suction orifice adjustment block 100 is approximately equal to the length (L0-L) of the truncated spiral parts of the male rotor and the female rotor. In practice, in order to retain a certain suction end safety clearance, s is slightly smaller than (L0-L) to overcome the dimensional changes caused by thermal expansion and contraction of the rotor.

[0019] like Figure 1 As shown, the left side of the outer contour line of the suction orifice adjustment block 100 includes a curve segment AB and an arc segment BC, the right side of the outer contour line of the suction orifice adjustment block 100 includes a curve segment FE and an arc segment ED, and the lower side of the outer contour line of the suction orifice adjustment block includes a curve segment CD.

[0020] The curve segment AB and the arc segment BC are connected sequentially from top to bottom. The shape of the curve segment AB is the same as the shape of the short side of any tooth of the female rotor. The shape of the arc segment BC is the same as the arc segment of the female rotor tooth root circle adjacent to the short side of any tooth of the female rotor. The starting angle a of the endpoint B of the curve segment AB is 2s for: Among them, a 1s is the starting angle of endpoint F of curve segment FE, z1 is the number of teeth of the male rotor, z2 is the number of teeth of the female rotor, and the starting angle of endpoint B refers to the combined angle of the angle between the line BO1 connecting endpoint B and the center O1 of arc segment BC and the line O1O2 connecting the center O1 of arc segment BC and the center O2 of arc segment ED (360° minus the angle A2 between the line BO1 and the line O1O2).

[0021] The curve segment FE and the arc segment ED are connected sequentially from top to bottom. The shape of the curve segment FE is the same as the shape of the long side of any tooth of the male rotor. The shape of the arc segment ED is the same as the arc segment of the male rotor tooth root circle adjacent to the long side of any tooth of the male rotor. The starting angle a of the endpoint F of the curve segment FE is 1s satisfy: Among them, τ is the torsion angle of the truncated male rotor, a 1s0 and τ0 are respectively the suction end angle and the torsion angle when the positive rotor is not truncated. The starting angle of the end point F refers to the combined angle of the angle between the line FO2 connecting the end point F and the center O2 of the arc segment ED and the line O2O1 connecting the center O2 of the arc segment ED and the center O1 of the arc segment BC (360° minus the angle A1 between the line FO2 and the line O2O1).

[0022] The curve segment CD connects the arc segment BC and the arc segment ED, and the shape of the curve segment CD is the same as the shape of the meshing line of the long side of the female rotor tooth and the long side of the male rotor tooth. The meshing line C'D' of the long side of the tooth of the female rotor 27 and the long side of the tooth of the male rotor 28 of the twin-screw compressor is as shown in FIG. Figure 3 The meshing line C'D' is the projection of the contact line of the tooth profiles of the female rotor 27 and the male rotor 28 on the axial end surface of the rotor. The shape of the curve segment CD is the same as that of the meshing line C'D'.

[0023] Starting angle a 2s Corresponding to the suction end angle of the female rotor, the starting angle a 1s Corresponding to the suction end angle of the male rotor. Long side and short side are technical terms in this field. A complete profile is divided into long side and short side at the tooth root. The long side refers to a curve with a relatively gentle change in curvature from the tooth top to the tooth root, and the short side refers to a curve with a relatively large change in curvature from the tooth top to the tooth root.

[0024] Optionally, the upper side of the outer contour line of the suction orifice adjustment block 100 includes an arc segment IG and an arc segment GH, and the arc segment IG and the arc segment GH are sequentially connected from left to right; the shape of the arc segment IG is the same as a section of the arc on the tooth top circle of the female rotor, and the arc segment IG is concentric with the arc segment BC; the shape of the arc segment GH is the same as a section of the arc on the tooth top circle of the male rotor, and the arc segment GH is concentric with the arc segment ED.

[0025] Optionally, the outer contour line of the air intake orifice adjustment block 100 includes a curve segment AI and a curve segment FH, wherein the curve segment AI is connected between the curve segment AB and the curve segment IG, and the curve segment FH is connected between the curve segment FE and the curve segment GH, and the curve segment AI and the curve segment FH are in arc shape. The purpose of setting the curve segment AI and the curve segment FH is to avoid sharp corners in the air intake orifice adjustment block 100, which are formed by rounding the sharp corners in actual manufacturing. In other embodiments, the sharp corners of the actual product may also be retained. In this case, the upper side of the outer contour line of the air intake orifice adjustment block 100 is composed of an arc segment AG and an arc segment GF, wherein the shape of the arc segment AG is the same as a section of the arc on the tooth top circle of the female rotor, and the arc segment AG is concentric with the arc segment BC; the shape of the arc segment GF is the same as a section of the arc on the tooth top circle of the male rotor, and the arc segment GF is concentric with the arc segment ED.

[0026] Preferably, the ratio of the length L0 of the spiral portion of the male rotor when not truncated to the diameter D0 of the spiral portion of the male rotor when not truncated is in the range of L0 / D0=1.1-2.1.

[0027] Preferably, the length L0 of the spiral part of the male rotor before truncating and the diameter D1 of the spiral part of the male rotor after truncating satisfy: L0=1.65*D1. The length L of the spiral part of the male rotor after truncating and the diameter D1 of the spiral part of the male rotor after truncating satisfy: L=1.1*D1.

[0028] Preferably, the torsion angle τ of the male rotor after truncation and the torsion angle τ0 when not truncated satisfy: τ≥0.625τ0.

[0029] In this embodiment, the air intake port adjustment block 100 is provided with n mounting through holes 11 extending along the thickness direction, where n≥3. In some specific implementations, the number of the mounting through holes 11 is 5.

[0030] Please refer to Figure 4 and Figure 5. In actual use, the suction orifice adjustment block 100 is installed on the end surface 211 of the suction end seat 21 of the twin-screw compressor facing the cylinder body 22. The suction end seat 21 is connected to the cylinder body 22, and the suction end seat 21 is provided with a plurality of suction orifices 210 that penetrate along the axial direction. Among them, the suction orifice adjustment block 100 is detachably connected to the end surface 211 of the suction end seat 21 facing the cylinder body 22. In this embodiment, the suction orifice adjustment block 100 is detachably connected to the end surface of the suction end seat 21 facing the cylinder body 12 by a plurality of bolts, and these bolts respectively pass through the aforementioned mounting through holes 11.

[0031] The center O1 of the arc segment BC is located on the central axis of the female rotor (i.e., the arc segment BC is concentric with the female rotor), and the radius of the arc segment BC is equal to the tooth root circle radius of the female rotor; the center O2 of the arc segment ED is located on the central axis of the male rotor (i.e., the arc segment ED is concentric with the male rotor), and the radius of the arc segment ED is equal to the tooth root circle radius of the male rotor. Points D and C are located on the line connecting the axis (center) of the female rotor and the axis (center) of the male rotor.

[0032] In some specific applications, when the torsion angle τ0 of the male rotor is 300° and the suction end angle is 279° before the male rotor is shortened, the torsion angle τ of the male rotor after the male rotor is shortened is 200° and the suction end angle is 279°. 1s The air intake opening adjustment block 100 of the embodiment of the present invention can also be made into different thicknesses and different a according to actual working conditions. 1s Angle size products, to achieve product serialization, such as Figure 6 As shown, the same model can be matched with different air intake orifices to achieve different internal volume ratios.

[0033] The embodiment of the present invention overcomes the adverse effects caused by the displacement of the suction orifice due to the changes in the rotor length and the torsion angle, so that the suction end position is accurately matched with the corresponding rotor length, thereby maximizing the inflation and avoiding the leakage channel between the suction orifice and the compression chamber, thereby improving the operating efficiency of the unit and enhancing the stability and reliability of the unit operation.

Claims

1. A suction port regulating block of a twin-screw compressor, wherein the twin-screw compressor comprises a male rotor and a female rotor, wherein the lengths of the spiral parts of the male rotor and the female rotor are truncated; characterized in that: The left side of the outer contour line of the air intake orifice adjustment block includes a curve segment AB and an arc segment BC, the right side of the outer contour line of the air intake orifice adjustment block includes a curve segment FE and an arc segment ED, and the lower side of the outer contour line of the air intake orifice adjustment block includes a curve segment CD; The curve segment AB and the arc segment BC are connected sequentially from top to bottom. The shape of the curve segment AB is the same as the shape of the short side of any tooth of the female rotor. The shape of the arc segment BC is the same as the arc segment of the female rotor tooth root circle adjacent to the short side of any tooth of the female rotor. The starting angle a of the endpoint B of the curve segment AB is 2s for: Among them, a 1s is the starting angle of the endpoint F of the curve segment FE, z1 is the number of teeth of the male rotor, z2 is the number of teeth of the female rotor, and the starting angle of the endpoint B refers to the angle between the line connecting the endpoint B and the center of the arc segment BC and the line connecting the center of the arc segment BC and the center of the arc segment ED; The curve segment FE and the arc segment ED are connected sequentially from top to bottom. The shape of the curve segment FE is the same as the shape of the long side of any tooth of the male rotor. The shape of the arc segment ED is the same as the arc segment of the male rotor tooth root circle adjacent to the long side of any tooth of the male rotor. The starting angle a of the endpoint F of the curve segment FE is 1s satisfy: Among them, τ is the torsion angle of the truncated male rotor, a 1s0 and τ0 are respectively the suction end angle and the torsion angle when the male rotor is not truncated, and the starting angle of the end point F refers to the angle formed by the line connecting the end point F and the center of the arc segment ED and the line connecting the center of the arc segment ED and the center of the arc segment BC; The curved segment CD connects the circular arc segment BC and the circular arc segment ED, and the shape of the curved segment CD is the same as the shape of the meshing line of the long side of the female rotor tooth and the long side of the male rotor tooth.

2. The suction port regulating block of the twin-screw compressor according to claim 1, characterized in that: The upper side of the outer contour line of the air intake port adjustment block includes an arc segment IG and an arc segment GH, and the arc segment IG and the arc segment GH are sequentially connected from left to right; The shape of the arc segment IG is the same as that of an arc segment on the tooth tip circle of the female rotor, and the arc segment IG is concentric with the arc segment BC; The shape of the arc segment GH is the same as that of an arc segment on the tooth tip circle of the male rotor, and the arc segment GH is concentric with the arc segment ED.

3. The suction port regulating block of the twin-screw compressor according to claim 2, characterized in that: The outer contour line of the air intake port adjustment block includes a curve segment AI and a curve segment FH. The curve segment AI is connected between the curve segment AB and the curve segment IG. The curve segment FH is connected between the curve segment FE and the curve segment GH. The curve segment AI and the curve segment FH are arc-shaped.

4. The suction port regulating block of the twin-screw compressor according to claim 1, characterized in that: The ratio of the length L0 of the spiral portion of the male rotor when not truncated to the diameter D0 of the spiral portion of the male rotor when not truncated is in the range of L0 / D0=1.1-2.

1.

5. The suction port regulating block of the twin-screw compressor according to claim 1, characterized in that: The length L0 of the spiral portion of the male rotor before being shortened and the diameter D1 of the spiral portion of the male rotor after being shortened satisfy: L0 = 1.65*D1.

6. The suction port regulating block of the twin-screw compressor according to claim 1, characterized in that: The length L of the spiral portion of the male rotor and the diameter D1 of the spiral portion of the male rotor satisfy: L=1.1*D1.

7. The suction port regulating block of the twin-screw compressor according to claim 1, characterized in that: The torsion angle τ after the male rotor is shortened and the torsion angle τ0 before the male rotor is not shortened satisfy: τ≥0.625τ0.

8. The suction port regulating block of the twin-screw compressor according to claim 1, characterized in that: The air intake port adjustment block is provided with n mounting through holes extending along the thickness direction, where n≥3.

9. A twin-screw compressor, comprising a suction end seat, a cylinder body, a male rotor and a female rotor, wherein the suction end seat is connected to the cylinder body, and the suction end seat is provided with a suction port extending through the axial direction, characterized in that: The twin-screw compressor comprises the suction port adjustment block according to any one of claims 1 to 8, wherein the suction port adjustment block is detachably connected to the end surface of the suction end seat facing the cylinder body; The center of the arc segment BC is located on the central axis of the female rotor, the center of the arc segment ED is located on the central axis of the male rotor, and points D and C are located on the line connecting the axis of the female rotor and the axis of the male rotor.

10. The twin-screw compressor according to claim 9, characterized in that: The air intake port adjustment block is detachably connected to the end surface of the air intake end seat facing the cylinder body through a plurality of bolts.

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