High-efficiency Yin-Yang screw rotor for oil-free screw air compressor

Abstract

The present invention discloses a high-efficiency yin-yang screw rotor for an oil-free screw air compressor, wherein the rotor profile includes a yin rotor tooth profile and a yang rotor tooth profile, wherein the number of rotor teeth of the yin rotor and the yang rotor are 6 teeth and 4 teeth respectively, and the minimum meshing clearance at the asymptotic point between the tooth end line C1-B1 and the transition line C2-B2, and the minimum meshing clearance at the asymptotic point between the transition line B1-A1 and the tooth end line B2-A2 form a first closed gap volume, and the meshing clearance at the asymptotic point between the meshing line A1-G1 and the tooth end line A2-H2, and the minimum meshing clearance at the asymptotic point between the transition line G1-F1 and the transition line H2-G2 form a second closed gap volume. The present invention achieves the optimal state of the inter-tooth area, the closed gap volume, and the leakage triangle area, reduces the unit specific power, thereby reducing energy consumption, and has excellent comprehensive performance.

Description

Technical Field

[0001] The invention belongs to the technical field of dry screw compressors, and in particular relates to a high-efficiency yin-yang screw rotor for an oil-free screw air compressor. Background Art

[0002] The screw rotor in the dry screw air compressor is its core component, and the quality of its rotor profile directly affects the complexity of the processing technology, service life and later maintenance cycle. The existing patent number is CN201820646809.5. A rotor profile of an oil-free twin-screw compressor includes a pair of mutually meshing male rotors and female rotors, wherein the male rotor is composed of 4 male rotor teeth connected end to end in the circumferential direction, and the female rotor is composed of 6 female rotor teeth connected end to end in the circumferential direction. The male rotor is fixedly connected to the driving shaft, and the female rotor is fixedly connected to the driven shaft. The end surface line of the male rotor teeth is composed of 1 male tooth end line and 1 male tooth root line connected end to end, and the end surface line of the female rotor teeth is composed of 1 female tooth end line and 1 female tooth root line connected end to end. The existing rotor profile has a large closed gap volume, a large rotor meshing gap, unstable operation, obvious compressed airflow noise, and general comprehensive performance. Summary of the invention

[0003] The purpose of the present invention is to solve the above technical problems and provide a high-efficiency yin-yang screw rotor for an oil-free screw air compressor, so as to achieve the optimal state of the inter-tooth area, closed gap volume, and leakage triangle area, reduce the unit specific power, thereby reducing energy consumption, and having excellent comprehensive performance. In order to achieve the above purpose, the technical solution of the present invention is as follows:

[0004] The oil-free screw air compressor uses a high-efficiency yin-yang screw rotor, including a yin rotor tooth profile and a yang rotor tooth profile. The number of teeth of the yin rotor and the yang rotor are 6 and 4 respectively.

[0005] The tooth profile of the female rotor is composed of 8 meshing lines connected smoothly from beginning to end, each meshing line includes a tooth tip line C1-B1, a transition line B1-A1, a tooth root line A1-I1, a tooth root line I1-H1, a transition line H1-G1, a transition line G1-F1, a transition line F1-E1, and a tooth tip line E1-D1 which are smoothly connected in sequence. A coordinate system is established with the center point O1 of the female rotor as the center of the circle, wherein the coordinate point is (-32.836, 8.114), (-40.270, 16.682), (-50.630, 23.218), (-43.671, -16.210), (-37.067, -8.465),

[0006] The tooth profile of the male rotor is composed of 7 meshing lines connected smoothly from beginning to end, each meshing line includes a tooth root line E2-D2, a tooth root line D2-C2, a transition line C2-B2, a tooth end line B2-A2, a tooth end line A2-H2, a transition line H2-G2, and a transition line G2-F2 which are connected smoothly in sequence. A coordinate system is established with the center point O2 of the male rotor as the center of the circle, wherein the coordinate point is (56.426, 8.048), (48.263, 16.157), (36.116, 20.118), (49.108, -12.593), (55.098, -3.016),

[0007] The minimum meshing gap where the tooth end line C1-B1 and the transition line C2-B2 approach each other, and the minimum meshing gap where the transition line B1-A1 and the tooth end line B2-A2 approach each other form a first closed gap volume, and the meshing gap where the meshing line A1-B1 and the tooth end line A2-H2 approach each other, and the minimum meshing gap where the transition line G1-F1 and the transition line H2-G2 approach each other form a second closed gap volume.

[0008] Specifically, the female rotor tooth profile also includes coordinate points (-45.384, -32.279), (-48.560, -25.673), (-34.031, -3.195), (-32.339, 4.342).

[0009] Specifically, the male rotor tooth profile also includes coordinate points (27.833, 19.594), (22.943, 26.127), (40.251, -19.314).

[0010] Specifically, the minimum meshing clearance between the tooth tip line C1 - B1 and the transition line C2 - B2 is 0.16 mm.

[0011] Specifically, the minimum meshing clearance between the transition line B1-A1 and the tooth end line B2-A2 is 0.147 mm.

[0012] Specifically, the minimum meshing clearance between the transition line G1-F1 and the transition line H2-G2 is 0.108 mm.

[0013] Specifically, the minimum meshing clearance between the tooth tip line E1 - D1 and the tooth root line E2 - D2 is 0.198 mm.

[0014] Specifically, the ratio of the axial working section length to the diameter of the male rotor is 1.82:1.

[0015] Compared with the prior art, the beneficial effects of the high-efficiency yin-yang screw rotor for the oil-free screw air compressor of the present invention are mainly reflected in:

[0016] The first closed gap volume is determined by setting the minimum meshing gap between the tooth end line C1-B1 and the transition line C2-B2, and the minimum meshing gap between the transition line B1-A1 and the tooth end line B2-A2; the second closed gap volume is determined by setting the minimum meshing gap between the meshing line A1-G1 and the tooth end line A2-H2, and the minimum meshing gap between the transition line G1-F1 and the transition line H2-G2; the sum of the first closed gap volume and the second closed gap volume is small, and through actual measurement, a smaller unit specific power of the air compressor can be achieved, energy consumption can be saved, and damaged power can be reduced; the positive rotor tooth profile line and the negative rotor tooth profile line can respectively achieve a larger tooth-to-tooth area, obtain a larger exhaust volume, and the leakage triangle area is smaller, which reduces the impact on the exhaust volume; the rotor surface adopts Teflon coating to avoid wear on the tooth surfaces of the positive and negative screws; the tooth-to-tooth area, closed gap volume, and leakage triangle area reach the optimal state, and the comprehensive performance is excellent. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the meshing structure of the tooth profile of the female rotor and the tooth profile of the male rotor according to an embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram of the tooth profile of the female rotor in this embodiment;

[0019] Figure 3 This is a schematic diagram of the tooth profile of the male rotor in this embodiment;

[0020] Figure 4 This is a schematic diagram of the female rotor tooth root meshing with the male rotor tooth end in this embodiment;

[0021] Figure 5 This is a schematic diagram of the female rotor tooth end meshing with the male rotor tooth root in this embodiment;

[0022] Figure 6 This is a partial enlarged schematic diagram of the closed gap volume in this embodiment;

[0023] The numbers in the figure represent:

[0024] 1. Tooth profile of negative rotor, 2. Tooth profile of positive rotor, 3. Volume of first closed gap, 4. Volume of second closed gap, 5. Area between teeth of positive rotor, 6. Area between teeth of negative rotor, 7. Area of ​​leakage triangle. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Example

[0026] Reference Figure 1-6 As shown, this embodiment is a high-efficiency yin-yang screw rotor for an oil-free screw air compressor, including a yin rotor tooth profile line 1 and a yang rotor tooth profile line 2, and the number of rotor teeth of the yin rotor and the yang rotor are 6 and 4 respectively.

[0027] The tooth profile line 1 of the female rotor is composed of 8 meshing lines connected smoothly from beginning to end. Each meshing line includes the tooth tip line C1-B1, transition line B1-A1, tooth root line A1-I1, tooth root line I1-H1, transition line H1-G1, transition line G1-F1, transition line F1-E1, and tooth tip line E1-D1, which are smoothly connected in sequence. A coordinate system is established with the center point O1 of the female rotor as the center of the circle, where the coordinate point is (-32.836, 8.114), (-40.270, 16.682), (-50.630, 23.218), (-45.384, -32.279), (-48.560, -25.673), (-43.671, -16.210), (-37.067, -8.465), (-34.031, -3.195), (-32.339, 4.342); coordinate unit is mm.

[0028] The positive rotor tooth profile 2 is composed of 7 meshing lines connected smoothly from beginning to end. Each meshing line includes the tooth root line E2-D2, tooth root line D2-C2, transition line C2-B2, tooth end line B2-A2, tooth end line A2-H2, transition line H2-G2, and transition line G2-F2, which are connected smoothly in sequence. A coordinate system is established with the positive rotor center point O2 as the center of the circle, where the coordinate point is (56.426, 8.048), (48.263, 16.157), (36.116, 20.118), (27.833, 19.594), (22.943, 26.127), (40.251, -19.314), (49.108, -12.593), (55.098, -3.016); coordinate unit is mm.

[0029] The minimum meshing clearance between the tooth tip line C1-B1 and the transition line C2-B2 is 0.16mm; the minimum meshing clearance between the transition line B1-A1 and the tooth tip line B2-A2 is 0.147mm; the minimum meshing clearance between the transition line G1-F1 and the transition line H2-G2 is 0.108mm; the minimum meshing clearance between the tooth tip line E1-D1 and the tooth root line E2-D2 is 0.198mm.

[0030] The minimum meshing clearance at the asymptotic point between the tooth end line C1-B1 and the transition line C2-B2, and the minimum meshing clearance at the asymptotic point between the transition line B1-A1 and the tooth end line B2-A2 form a first closed gap volume 3; the minimum meshing clearance at the asymptotic point between the meshing line A1-G1 and the tooth end line A2-H2, and the minimum meshing clearance at the asymptotic point between the transition line G1-F1 and the transition line H2-G2 form a second closed gap volume 4.

[0031] The tooth area of ​​the male rotor is 210.326 mm 2 The area between the teeth of the female rotor is 176.499 mm 2 .

[0032] In this embodiment, the ratio of the axial working section length to the diameter of the male rotor is 1.82:1. When the internal pressure ratio is the same, its moment of inertia increases, so that the rotor has good rigidity and improves the reliability of operation.

[0033] When applying this embodiment, the first closed gap volume 3 is determined by setting the minimum meshing gap between the tooth end line C1-B1 and the transition line C2-B2, and the minimum meshing gap between the transition line B1-A1 and the tooth end line B2-A2; the second closed gap volume 4 is determined by setting the minimum meshing gap at the approach of the meshing line A1-G1 and the tooth end line A2-H2, and the minimum meshing gap between the transition line G1-F1 and the transition line H2-G2; the sum of the first closed gap volume 3 and the second closed gap volume 4 is small, and through actual measurement, a smaller unit specific power of the air compressor can be achieved, energy consumption can be saved, and damaged power can be reduced; the positive rotor tooth profile line 1 and the negative rotor tooth profile line 2 can respectively achieve a larger tooth-to-tooth area and obtain a larger exhaust volume, and the leakage triangle area 7 is smaller, which reduces the impact on the exhaust volume; the rotor surface adopts Teflon coating to avoid wear on the tooth surfaces of the positive and negative screws; the tooth-to-tooth area, closed gap volume, and leakage triangle area reach the optimal state, and the comprehensive performance is excellent.

[0034] Laboratory data: The comparison example is the TG-C18 dry screw compressor produced by Ningbo Inderfil Machinery Technology Co., Ltd. The test method complies with the requirements of GB / T3853-2017 and the evaluation method of GB19153-2019. The unit specific power = input power / measured flow rate, as shown in the following table.

[0035] Through the analysis of the data in the above table, the oil-free screw air compressor of this embodiment uses a high-efficiency yin-yang screw rotor, compared with the existing compressor, at the same exhaust pressure, the exhaust port temperature is lower, which reflects the comprehensive performance advantages of the whole machine; while having a higher measured flow rate, the unit has a lower power density and is more energy-saving and power-saving.

[0036] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0037] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted to facilitate understanding of the present invention and are not intended to limit the present invention. Any technician in the field to which the present invention belongs can make any modifications and changes in the form and details of implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. The high-efficiency yin-yang screw rotor for oil-free screw air compressor has a rotor profile including a yin rotor tooth profile and a yang rotor tooth profile. The number of teeth of the yin rotor and the number of teeth of the yang rotor are 6 and 4 respectively, and the characteristics are: The tooth profile of the female rotor is composed of 8 meshing lines connected smoothly from beginning to end, each meshing line includes a tooth tip line C1-B1, a transition line B1-A1, a tooth root line A1-I1, a tooth root line I1-H1, a transition line H1-G1, a transition line G1-F1, a transition line F1-E1, and a tooth tip line E1-D1 which are smoothly connected in sequence. A coordinate system is established with the center point O1 of the female rotor as the center of the circle, wherein the coordinate point is (-32.836, 8.114), (-40.270, 16.682), (-50.630, 23.218), (-43.671, -16.210), (-37.067, -8.465), The tooth profile of the male rotor is composed of 7 meshing lines connected smoothly from beginning to end, each meshing line includes a tooth root line E2-D2, a tooth root line D2-C2, a transition line C2-B2, a tooth end line B2-A2, a tooth end line A2-H2, a transition line H2-G2, and a transition line G2-F2 which are connected smoothly in sequence. A coordinate system is established with the center point O2 of the male rotor as the center of the circle, wherein the coordinate point is (56.426, 8.048), (48.263, 16.157), (36.116, 20.118), (49.108, -12.593), (55.098, -3.016), The tooth area of ​​the male rotor is 210.326 mm 2 ; The area between the teeth of the female rotor is 176.499 mm 2 ; The minimum meshing gap at the asymptotic point between the tooth tip line C1-B1 and the transition line C2-B2, and the minimum meshing gap at the asymptotic point between the transition line B1-A1 and the tooth tip line B2-A2 form a first closed gap volume, and the meshing gap at the asymptotic point between the meshing line A1-G1 and the tooth tip line A2-H2, and the minimum meshing gap at the asymptotic point between the transition line G1-F1 and the transition line H2-G2 form a second closed gap volume; The minimum meshing clearance between the tooth tip line C1-B1 and the transition line C2-B2 is 0.16 mm; The minimum meshing clearance between the transition line B1-A1 and the tooth end line B2-A2 is 0.147 mm; The minimum meshing clearance between the transition line G1-F1 and the transition line H2-G2 is 0.108 mm; The minimum meshing clearance between the tooth tip line E1-D1 and the tooth root line E2-D2 is 0.198 mm; The ratio of the axial working section length to the diameter of the male rotor is 1.82:

1.

2. The high-efficiency yin-yang screw rotor for oil-free screw air compressor according to claim 1, characterized in that: The female rotor tooth profile also includes coordinate points (-45.384, -32.279), (-48.560, -25.673), (-34.031, -3.195), (-32.339, 4.342).

3. The high-efficiency yin-yang screw rotor for oil-free screw air compressor according to claim 1, characterized in that: The male rotor tooth profile also includes coordinate points (27.833, 19.594), (22.943, 26.127), (40.251, -19.314).

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