Gear pump

Abstract

The utility model discloses a gear pump, which belongs to the technical field of gear pumps and comprises a female rotating wheel and a male rotating wheel which are meshed with each other. The tooth profile of the female rotating wheel and the tooth profile of the male rotating wheel are both asymmetric tooth profiles; both the female rotating wheel and the male rotating wheel are herringbone teeth; when the female rotating wheel is meshed with the male rotating wheel, the tooth profile of the female rotating wheel can be matched with the tooth profile of the male rotating wheel; due to the fact that the tooth profiles of the female rotating wheel and the male rotating wheel are asymmetric, it is guaranteed that the tooth profiles of the female rotating wheel and the male rotating wheel can be matched, the female rotating wheel and the male rotating wheel can completely coincide when being meshed, and structural support is provided for avoiding forming a closed space between the teeth; and the female rotating wheel and the male rotating wheel are both provided with herringbone teeth, so that the rotating wheels can be further completely meshed, and the overall stability can be improved to reduce the vibration and noise of the gear.

Description

Technical Field

[0001] The utility model belongs to the technical field of gear pumps, in particular to a gear pump. Background Art

[0002] Traditional involute gear pumps often have the following problems during use:

[0003] 1) When the gear pump is conveying hydraulic oil, the closed volume at the intersection of the gears (tooth profile is an involute) will change regularly over time. However, due to the special tooth profile structure of the gear, part of the hydraulic oil is often sealed between the teeth. Due to the incompressibility of the hydraulic oil, this type of gear pump is prone to oil entrapment, which in turn causes the gears to produce great vibration and noise, and even affects the normal operation of the hydraulic system. In order to solve this problem, it is usually necessary to open unloading grooves on the front and rear covers or floating sleeves, but this will reduce the efficiency of the gear pump.

[0004] 2) During the use of the gear pump, there is an unavoidable pressure imbalance problem in the oil suction chamber and the oil pressure chamber. When the unbalanced pressure acts on the gears and the rotating shaft, an unbalanced radial force will be generated; as the pressure gradually increases, the unbalanced radial force applied to the gears and the rotating shaft will also increase. This will not only increase the deflection of the gear to cause the gear end face side clearance leakage problem, but also shorten the service life of the bearings, gears and rotating shafts. Utility Model Content

[0005] The technical problem to be solved by the utility model is: how to provide a gear pump which can improve working efficiency and prolong service life while ensuring working stability.

[0006] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0007] A gear pump comprises a female rotor and a male rotor meshing with each other;

[0008] The tooth profiles of the female rotating wheel and the male rotating wheel are both asymmetric tooth profiles;

[0009] The female rotating wheel and the male rotating wheel both have herringbone teeth;

[0010] When the female rotating wheel and the male rotating wheel are meshed, the tooth profile of the female rotating wheel and the tooth profile of the male rotating wheel can be matched.

[0011] Furthermore, the diameter ratio of the female rotor to the male rotor is 6:4.

[0012] Furthermore, the gear ratio of the female rotating wheel to the male rotating wheel is 6:4.

[0013] Furthermore, when the female rotating wheel and the male rotating wheel are meshed, the tooth clearance between the female rotating wheel and the male rotating wheel is 0.015 mm to 0.030 mm.

[0014] Furthermore, when the working medium is hydraulic oil, the tooth clearance between the female rotor and the male rotor is 0.020 mm to 0.030 mm.

[0015] Furthermore, when the negative rotating wheel and the positive rotating wheel are meshed, the linear speed of the negative rotating wheel and the positive rotating wheel is 3m / s to 7.5m / s.

[0016] Furthermore, when the female rotor and the male rotor are meshed, the pressure-bearing sizes of the liquid inlet ends of the female rotor and the male rotor are 6 bar to 9.8 bar.

[0017] Furthermore, when the female rotor and the male rotor are meshed, the pressure-bearing size of the liquid outlet end of the female rotor and the liquid outlet end of the male rotor is 7 bar to 14 bar.

[0018] Furthermore, when the female rotor is meshed with the male rotor, the liquid flow rate between the liquid outlet end of the female rotor and the liquid outlet end of the male rotor is 180 L / min-240 L / min.

[0019] The beneficial effects of the utility model are as follows: the gear pump provided by the utility model, since the tooth profiles of the female rotor and the male rotor are asymmetric, ensures that the tooth profiles of the female rotor and the male rotor can be adapted to each other, so that the female rotor and the male rotor can completely overlap when meshing, and provide structural support to avoid the formation of a closed space between the teeth; and ensures that the female rotor and the male rotor are herringbone teeth, which can not only further enable the wheels to fully mesh, but also improve the overall stability to reduce the vibration and noise of the gears. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Shown is a front view of a gear pump according to a specific embodiment of the utility model;

[0021] Figure 2 Shown is a left side view of a gear pump according to a specific embodiment of the utility model;

[0022] Figure 3 Shown is a schematic structural diagram of the tooth profile of the male rotor in a specific embodiment of the utility model;

[0023] Description of labels:

[0024] 1. Negative rotor;

[0025] 2. Yang wheel;

[0026] 3. The first arc segment;

[0027] 4. The first elliptical segment;

[0028] 5. The first arc envelope;

[0029] 6. The second arc segment;

[0030] 7. Second arc envelope;

[0031] 8. The second ellipse segment. DETAILED DESCRIPTION

[0032] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in conjunction with the implementation modes and the accompanying drawings.

[0033] The most critical concept of the utility model is that the asymmetric tooth profile is designed so that the tooth profiles of the female rotor and the male rotor can be adapted to each other, so that the female rotor and the male rotor can completely overlap when meshing, avoiding the formation of a closed space between the teeth to provide structural support; and ensuring that both the female rotor and the male rotor are herringbone teeth, which can not only further enable the wheels to fully mesh, but also improve the overall stability to reduce the vibration and noise of the gears.

[0034] Please refer to Figures 1 to 3 The gear pump provided by the utility model comprises a female rotor 1 and a male rotor 2 meshing with each other;

[0035] The tooth profiles of the female rotating wheel 1 and the male rotating wheel 2 are both asymmetric tooth profiles;

[0036] Both the female rotating wheel 1 and the male rotating wheel 2 have herringbone teeth;

[0037] When the negative rotating wheel 1 and the positive rotating wheel 2 are meshed, the tooth profile of the negative rotating wheel 1 and the tooth profile of the positive rotating wheel 2 can be matched.

[0038] Specifically, the tooth profile of the negative rotating wheel 1 and the tooth profile of the positive rotating wheel 2 are adapted to each other, which means that during the rotation and meshing process of the negative rotating wheel 1 and the positive rotating wheel 2, the tooth profile of the negative rotating wheel 1 and the tooth profile of the positive rotating wheel 2 can be completely overlapped, or at a certain angle, the tooth spacing at any position of the negative rotating wheel 1 and the positive rotating wheel 2 is equal. This avoids the phenomenon of oil entrapment caused by the formation of a closed space between the teeth during the meshing process of the negative rotating wheel 1 and the positive rotating wheel 2, thereby causing gear vibration and abnormal noise.

[0039] From the above description, it can be seen that the beneficial effect of the utility model is to provide a gear pump. Compared with the transmission gear, the tooth profile of the traditional gear is a symmetrical involute tooth profile, and the involute tooth profile will inevitably lead to the formation of a closed space between the teeth during the gear meshing process, thereby causing oil trapping. The utility model designs the tooth profile of the female rotating wheel 1 and the tooth profile of the male rotating wheel 2 to be asymmetrical, which can ensure that the tooth profile of the female rotating wheel 1 and the tooth profile of the male rotating wheel 2 can be adapted to each other, so that the female rotating wheel 1 and the male rotating wheel 2 can completely overlap when meshing, and provide structural support to avoid the formation of a closed space between the teeth; and ensure that the female rotating wheel 1 and the male rotating wheel 2 are both herringbone teeth, which can not only further make the wheels fully meshed, but also improve the overall stability to reduce the vibration and noise of the gears.

[0040] Furthermore, the diameter ratio of the female rotor 1 to the male rotor 2 is 6:4.

[0041] Furthermore, the gear ratio of the female rotating wheel 1 to the male rotating wheel 2 is 6:4.

[0042] Specifically, the gear ratio between the female rotating wheel 1 and the male rotating wheel 2 may also be 7:5.

[0043] From the above description, it can be seen that the asymmetric tooth profile design is matched with the diameter ratio and the tooth number ratio of the female rotor 1 and the male rotor 2, so that the stiffness of the female rotor 1 and the male rotor 2 can be more than twice the stiffness of the involute gears of the same diameter. Therefore, when subjected to unbalanced radial forces of the same magnitude, the gear pump of the utility model will produce extremely small, even negligible deformation, thereby providing structural support for the hydraulic system to reduce vibration and noise.

[0044] Further, when the female rotating wheel 1 and the male rotating wheel 2 are meshed, the tooth clearance between the female rotating wheel 1 and the male rotating wheel 2 is 0.015 mm to 0.030 mm. Preferably, the tooth clearance between the female rotating wheel 1 and the male rotating wheel 2 may be 0.015 mm, 0.016 mm, 0.017 mm, 0.018 mm, 0.019 mm, 0.020 mm, 0.021 mm, 0.022 mm, 0.023 mm, 0.024 mm, 0.025 mm, 0.026 mm, 0.027 mm, 0.028 mm, 0.029 mm or 0.030 mm.

[0045] Furthermore, when the working medium is hydraulic oil, the tooth clearance between the negative rotating wheel 1 and the positive rotating wheel 2 is 0.020 mm to 0.030 mm. Preferably, the tooth clearance between the negative rotating wheel 1 and the positive rotating wheel 2 can be 0.020 mm, 0.021 mm, 0.022 mm, 0.023 mm, 0.024 mm, 0.025 mm, 0.026 mm, 0.027 mm, 0.028 mm, 0.029 mm or 0.030 mm.

[0046] Specifically, the working medium of the gear pump of the utility model can be any liquid. The oily liquid with a temperature less than or equal to 130°C, a viscosity range of 3-500cst, non-corrosive and free of solid particles and fibers is the preferred working medium of the gear pump of this scheme, and the gear pump has a better operating effect under the conditions that the gear linear speed of the negative runner 1 and the positive runner 2 are both 3m / s~7.5m / s, the inlet oil pressure of the negative runner 1 and the positive runner 2 are both 6bar~9.8bar, the outlet oil pressure of the negative runner 1 and the positive runner 2 are both 7bar~14bar, and the liquid flow rate between the liquid outlet end of the negative runner 1 and the liquid outlet end of the positive runner 2 is 180L / min~240L / min.

[0047] Preferably, the gear linear speed of the negative rotor 1 and the positive rotor 2 can be 3m / s, 3.5m / s, 4m / s, 4.5m / s, 5m / s, 5.5m / s, 6m / s, 6.5m / s, 7m / s or 7.5m / s; the inlet oil pressure of the negative rotor 1 and the positive rotor 2 can be 6bar, 6.2bar, 6.4bar, 6.6bar, 6.8bar, 7bar, 7.2bar, 7.4bar, 7.6bar, 7.8bar, 8bar, 8.2bar, 8.4bar, 8.6bar, 8.8bar, 9bar, 9.2bar, 9.4bar, 9.6bar or 9.8bar; the outlet oil pressure of the negative rotor 1 and the positive rotor 2 can be 7bar, 8bar, 9bar, 10bar, 11bar, 12bar, 13bar or 14bar.

[0048] From the above description, it can be seen that the design has made specific improvements to the tooth clearance between the negative rotor 1 and the positive rotor 2, and when the working medium is hydraulic oil, the tooth clearance between the negative rotor 1 and the positive rotor 2 has been further optimized, thereby ensuring that there is enough space between the negative rotor 1 and the positive rotor 2 for the flow of hydraulic oil, thereby avoiding the flow path of the hydraulic oil being blocked due to too small tooth clearance to cause oil trapping, which in turn causes periodic vibration and abnormal noise during the rotation and meshing process of the negative rotor 1 and the positive rotor 2, ultimately affecting the service life of the gear pump.

[0049] Furthermore, the tooth profile of the male rotor 2 includes a first circular arc segment 3, a first elliptical segment 4, a first circular arc envelope 5, a second circular arc segment 6, a second circular arc envelope 7 and a second elliptical segment 8 which are connected in sequence.

[0050] Specifically, the tooth profile trajectory of the male wheel 2 is referenced Figure 3 , the first arc segment 3 is Figure 3 AB segment, first ellipse segment 4 Figure 3 BC segment, first arc envelope 5 Figure 3 CD segment, second arc segment 6 Figure 3 DE segment in the second arc envelope 7 Figure 3 Segment EF, second ellipse segment 8 Figure 3 The FG segment in .

[0051] Specifically, the first arc segment 3, the first elliptical segment 4, the first arc envelope 5, the second arc segment 6, the second arc envelope 7 and the second elliptical segment 8 are all continuously differentiable curves, and the tooth profile formed by the first arc segment 3, the first elliptical segment 4, the first arc envelope 5, the second arc segment 6, the second arc envelope 7 and the second elliptical segment 8 is also a continuously differentiable curve. This design can effectively ensure the smoothness of the tooth profile surface and reduce the friction during rotation, so that the gear pump can use all the power to drive the flow of hydraulic oil, avoid unnecessary losses, and improve the working efficiency of the gear pump.

[0052] Furthermore, when the female rotor 1 and the male rotor 2 are meshed, with the pitch circle of the male rotor 2 as the dividing line, the first arc segment 3 and the second elliptical segment 8 are both located inside the pitch circle of the male rotor 2;

[0053] The first elliptical segment 4 , the first circular arc envelope 5 , the second circular arc segment 6 and the second circular arc envelope 7 are all located outside the pitch circle of the male rotor 2 .

[0054] Furthermore, the center of the first arc segment 3 and the center of the second arc segment 6 are both located on the pitch circle of the male rotor 2. The center of the first arc segment 3 is Figure 3 The center of the second arc segment 6 is Figure 3 Point I in .

[0055] Furthermore, the center of the second ellipse segment 8 is located on a straight line where the end point of the extension direction of the second ellipse segment 8 and the center of the pitch circle of the male rotor 2 are located.

[0056] Specifically, the second ellipse segment 8 only needs to ensure that any center of the circle can be located on a straight line between the end point of the extension direction of the second ellipse segment 8 and the center of the pitch circle of the male rotor 2 .

[0057] From the above description, it can be seen that the design has made specific improvements to the composition trajectory of the tooth profile of the male wheel 2. The continuous tooth profile surface formed by connecting multiple sections of smooth curved surfaces can ensure that the male wheel 2 and the female wheel 1 can smoothly complete the meshing work, avoiding the formation of a closed space between the teeth that can cause oil trapping due to the meshing surfaces of the two being not smooth enough, thereby causing the gear pump to have problems such as continuous shaking and abnormal noise.

[0058] The gear pump of the utility model can assist the oil transmission work of the hydraulic system.

[0059] Please refer to Figures 1 to 3 , Embodiment 1 of the present utility model is:

[0060] A gear pump comprises a female rotor 1 and a male rotor 2 meshing with each other; the tooth profile of the female rotor 1 and the tooth profile of the male rotor 2 are both asymmetric tooth profiles; the female rotor 1 and the male rotor 2 are both herringbone teeth; when the female rotor 1 and the male rotor 2 are meshing, the tooth profile of the female rotor 1 and the tooth profile of the male rotor 2 can be adapted to each other; the diameter ratio of the female rotor 1 and the male rotor 2 is 6:4; the tooth number ratio of the female rotor 1 and the male rotor 2 is 6:4; when the female rotor 1 and the male rotor 2 are meshing, the tooth clearance between the female rotor 1 and the male rotor 2 is 0.015mm; the gear linear speed of the female rotor 1 and the male rotor 2 can both be 5m / s; the inlet oil pressure of the female rotor 1 and the male rotor 2 can both be 6bar; the outlet oil pressure of the female rotor 1 and the male rotor 2 can both be 9bar.

[0061] The tooth profile of the male rotor 2 includes a first arc segment 3, a first elliptical segment 4, a first arc envelope 5, a second arc segment 6, a second arc envelope 7 and a second elliptical segment 8 which are connected in sequence; when the female rotor 1 and the male rotor 2 are meshed, with the pitch circle of the male rotor 2 as the dividing line, the first arc segment 3 and the second elliptical segment 8 are both located on the inner side of the pitch circle of the male rotor 2; the first elliptical segment 4, the first arc envelope 5, the second arc segment 6 and the second arc envelope 7 are all located on the outer side of the pitch circle of the male rotor 2; the center of the first arc segment 3 and the center of the second arc segment 6 are both located on the pitch circle of the male rotor 2; the center of the second elliptical segment 8 is located on the straight line where the end point of the extension direction of the second elliptical segment 8 and the center of the pitch circle of the male rotor 2 are located.

[0062] Embodiment 2 of the present utility model is:

[0063] On the basis of the first embodiment, when the working medium is hydraulic oil, the tooth clearance between the female rotating wheel 1 and the male rotating wheel 2 of the second embodiment is 0.020 mm.

[0064] The working principle of the utility model is as follows: after starting the gear pump, the hydraulic oil can be transported from one end where the teeth of the female wheel 1 and the teeth of the male wheel 2 are gradually meshed to the other end where the teeth of the female wheel 1 and the teeth of the male wheel 2 are gradually separated through the rotation of the female wheel 1 and the male wheel 2, thereby stably and continuously transporting the hydraulic oil to the equipment or device in need at the rear end.

[0065] In summary, the gear pump provided by the present invention has a symmetrical involute tooth profile compared to the transmission gear, and the involute tooth profile will inevitably lead to the formation of a closed space between the teeth during the gear meshing process, thereby causing oil trapping. The present invention ensures that the tooth profile of the female wheel and the tooth profile of the male wheel are compatible by designing the tooth profile of the female wheel and the tooth profile of the male wheel to be asymmetrical, so that the female wheel and the male wheel can completely overlap when meshing, and provide structural support to avoid the formation of a closed space between the teeth; and ensure that both the female wheel and the male wheel are herringbone teeth, so that the rotor profile of the screw compressor that can achieve complete meshing of the female wheel and the male wheel can be used, which not only solves the problem of liquid trapping caused by incomplete meshing of the rotor profile of the traditional gear pump and the vibration noise caused by pulsation, but also further improves the volumetric efficiency, so that the stiffness of the rotor is improved to a certain extent, thereby improving the stability of the overall operation.

[0066] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent transformations made using the contents of the specification and drawings of the present invention, or directly or indirectly applied in the relevant technical field, are also included in the patent protection scope of the present invention.

Claims

1. A gear pump, characterized in that: It includes a female rotating wheel and a male rotating wheel meshing with each other; The tooth profiles of the female rotating wheel and the male rotating wheel are both asymmetric tooth profiles; The female rotating wheel and the male rotating wheel both have herringbone teeth; When the female rotating wheel and the male rotating wheel are meshed, the tooth profile of the female rotating wheel and the tooth profile of the male rotating wheel can be matched.

2. The gear pump according to claim 1, characterized in that: The diameter ratio of the female rotor to the male rotor is 6:

4.

3. The gear pump according to claim 1, characterized in that: When the female rotating wheel and the male rotating wheel are meshed, the tooth clearance between the female rotating wheel and the male rotating wheel is 0.015 mm to 0.030 mm.

4. The gear pump according to claim 3, characterized in that: When the working medium is hydraulic oil, the tooth clearance between the female rotating wheel and the male rotating wheel is 0.020 mm to 0.030 mm.

5. The gear pump according to claim 1, characterized in that: When the female rotor and the male rotor are meshed, the pressures at the liquid inlet ends of the female rotor and the male rotor are 6 bar to 9.8 bar.

6. The gear pump according to claim 1, characterized in that: When the female rotor and the male rotor are meshed, the pressure-bearing size of the liquid outlet end of the female rotor and the liquid outlet end of the male rotor is 7 bar to 14 bar.

7. The gear pump according to claim 1, characterized in that: When the female rotor is meshed with the male rotor, the liquid flow rate between the liquid outlet end of the female rotor and the liquid outlet end of the male rotor is 180L / min to 240L / min.

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