Gear pump

Abstract

The utility model discloses a gear pump which comprises a shell and a conveying assembly, the shell is provided with a cavity, a liquid inlet and a liquid outlet, the liquid inlet and the liquid outlet are both communicated with the cavity so that liquid can flow into the cavity through the liquid inlet and flow out through the liquid outlet, and the conveying assembly comprises an outer gear, an inner gear and a crescent plate. The inner gear, the outer gear and the crescent plate are all rotatably arranged in the cavity, the outer gear is rotatably arranged in the inner gear, one part of the outer gear is meshed with the inner gear, one part of the outer gear and the inner gear are arranged in a spaced mode to form an installation cavity, the crescent plate is arranged in the installation cavity, and a damping groove is formed in the end of the crescent plate. The damping groove extends in the circumferential direction of the crescent plate, and the cross sectional area of the damping groove is gradually reduced in the direction from the end of the crescent plate to the middle of the crescent plate. The gear pump disclosed by the utility model has the advantages of simple structure, low noise and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of liquid pumps, in particular to a gear pump. BACKGROUND

[0002] The internal meshing gear pump is a volumetric pump working by the principle of gear meshing, and its core function is to realize fluid delivery and pressure increase through the rotational movement of gears, and is widely used in the fields of industry, automobile, aerospace, etc.

[0003] In the related art, when the internal meshing gear pump rotates at high speed, sudden changes in oil pressure can cause problems such as vibration, loud noise, and large pressure fluctuation. CONTENT OF THE INVENTION

[0004] The present application aims to at least partially solve one of the technical problems in the related art.

[0005] To this end, the embodiments of the present application propose a gear pump with small vibration and noise and simple structure.

[0006] The gear pump according to the embodiments of the present application is characterized in that it comprises a housing having a chamber, a liquid inlet and a liquid outlet, the liquid inlet and the liquid outlet are both in communication with the chamber, so that the liquid flows into the chamber through the liquid inlet and flows out through the liquid outlet; a conveying assembly comprising an outer gear, an inner gear and a crescent plate, the inner gear, the outer gear and the crescent plate are all rotatably arranged in the chamber, the outer gear is rotatably arranged in the inner gear, a part of the outer gear is meshed with the inner gear, and another part of the outer gear is spaced apart from the inner gear to form a mounting cavity, the crescent plate is arranged in the mounting cavity, an end portion of the crescent plate is provided with a damping groove, the damping groove extends along the circumference of the crescent plate, and the cross-sectional area of the damping groove gradually decreases in the direction from the end portion of the crescent plate towards the middle portion of the crescent plate.

[0007] The gear pump according to the embodiments of the present application can make the pressure of the oil liquid slowly and smoothly change, effectively solve the problems of sudden change of oil pressure in the gear pump, large running vibration, loud noise and large pressure fluctuation of the gear pump, and reduce the running noise of the gear pump.

[0008] In some embodiments, the crescent plate comprises a first crescent plate and a second crescent plate, the first crescent plate is arranged in the mounting cavity and is provided with a mounting groove on the side away from the inner gear, the second crescent plate is arranged in the mounting groove, the first crescent plate abuts against the outer gear, and the second crescent plate abuts against the inner gear.

[0009] In some embodiments, the end of the first crescent-shaped plate is provided with the damping groove, and the damping groove is located on the side of the first crescent-shaped plate away from the external gear.

[0010] In some embodiments, the damping groove comprises a first groove formed at one end of the first crescent-shaped plate and a second groove formed at the other end of the first crescent-shaped plate.

[0011] In some embodiments, the end of the second crescent-shaped plate is provided with the damping groove, and the damping groove is located on the side of the second crescent-shaped plate away from the external gear.

[0012] In some embodiments, the damping groove comprises a third groove formed at one end of the second crescent-shaped plate and a fourth groove formed at the other end of the second crescent-shaped plate.

[0013] In some embodiments, the shape of the inner circumferential surface of the damping groove is any one of a triangle, a semicircle, a semi-ellipse, a rectangle, etc.

[0014] In some embodiments, the depth of the damping groove gradually decreases towards the middle of the crescent-shaped plate from the end of the crescent-shaped plate, and the depth of the damping groove is flush with the end surface of the crescent-shaped plate.

[0015] In some embodiments, the number of the damping grooves is multiple, and the multiple damping grooves are arranged at intervals along the width of the crescent-shaped plate.

[0016] In some embodiments, the circumferential length of the damping groove corresponds to a central angle of the damping groove, and the central angle of the damping groove is not greater than the pitch angle of the external gear. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a structural schematic diagram of a gear pump according to an embodiment of the present application.

[0018] Figure 2 is a structural schematic diagram of a crescent-shaped plate of a gear pump according to an embodiment of the present application.

[0019] 100, gear pump; 1, conveying assembly; 2, external gear; 3, internal gear; 4, crescent-shaped plate; 41, damping groove; 42, first crescent-shaped plate; 43, second crescent-shaped plate. DETAILED DESCRIPTION

[0020] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the drawings. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation of the present application.

[0021] The gear pump 100 according to an embodiment of the present application is described below with reference to the drawings.

[0022] As Figures 1-2 shown, the gear pump 100 according to the embodiment of the utility model comprises a shell and a conveying assembly 1.

[0023] The shell has a chamber, a liquid inlet and a liquid outlet, and the liquid inlet and the liquid outlet are both communicated with the chamber so as to allow the liquid to flow into the chamber through the liquid inlet and flow out of the shell through the liquid outlet. Specifically, the shell forms a closed chamber inside, and the liquid inlet and the liquid outlet are both arranged on the shell and communicated with the chamber, so that the liquid enters the shell from the liquid inlet and then flows out of the shell through the liquid outlet.

[0024] The conveying assembly 1 comprises an outer gear 2, an inner gear 3 and a crescent plate 4, the inner gear 3, the outer gear 2 and the crescent plate 4 are all rotatably arranged in the chamber, the outer gear 2 is rotatably arranged in the inner gear 3, a part of the outer gear 2 is engaged with the inner gear 3, and another part of the outer gear 2 is spaced apart from the inner gear 3 to form a mounting cavity, and the crescent plate 4 is arranged in the mounting cavity, an end portion of the crescent plate 4 is provided with a damping groove 41, the damping groove 41 extends along the circumferential direction of the crescent plate 4, and the cross-sectional area of the damping groove 41 gradually decreases along the direction from the end portion of the crescent plate 4 towards the middle portion of the crescent plate 4. Specifically, as Figures 1-2 shown, the conveying assembly 1 is arranged in the shell and located between the liquid inlet and the liquid outlet, and the conveying assembly 1 is used for conveying the liquid, the inner gear 3 is arranged in the outer gear 2, and the lower end of the inner gear 3 is engaged with the outer gear 2, the upper end of the inner gear 3 is spaced apart from the upper end of the outer gear 2 to form a mounting cavity, the crescent plate 4 is arranged in the mounting cavity and abuts against the inner gear 3 and the outer gear 2 respectively, the crescent plate 4 is provided with the damping groove 41, the damping groove 41 extends along the circumferential direction of the crescent plate 4, and the cross-sectional area of the inner circumferential surface of the damping groove 41 gradually decreases along the vicinity of the middle portion of the crescent plate 4.

[0025] The conveying assembly 1 has a liquid suction stage, a compression stage and a liquid discharge stage.

[0026] In the liquid suction stage: when the outer gear 2 starts to rotate under the driving of the driving shaft, the meshing teeth pairs of the outer gear 2 and the inner gear 3 gradually disengage, and a gradually expanding volume cavity is formed between the outer gear 2, the inner gear 3 and the crescent plate 4, and the expanding volume cavity generates a local vacuum to thereby attract the liquid to enter the chamber through the liquid inlet. The crescent plate 4 plays a guiding role in this stage to ensure that the liquid smoothly enters the interdental volume.

[0027] When the damping groove 41 is located on the upper end face of the crescent plate 4 and is adjacent to the liquid inlet, since the damping groove 41 extends along the circumference of the crescent plate 4 and its cross-sectional area gradually decreases from the end of the crescent plate 4 towards the middle, when the liquid enters the tooth tip oil cavity between the inner gear 3 and the crescent plate 4 from the liquid inlet, the liquid will flow between the inner gear 3 and the crescent plate 4 through the damping groove 41. The liquid can be pre-pressurized before entering the high-pressure area through the damping groove 41. As the liquid flows to the middle of the main crescent plate 4, the width of the damping groove 41 gradually decreases, which causes the pressurization space between the damping groove 41 and the inner gear 3 to also correspondingly decrease, so that the pressure of the oil liquid can slowly and smoothly transition to the high-pressure state, ensuring that the inner gear 3 can adapt to the change of high pressure in advance when it reaches the high-pressure area, avoiding vibration and noise caused by sudden pressure change.

[0028] When the damping groove 41 is located on the lower end face of the crescent plate 4 and is adjacent to the liquid inlet, since the damping groove 41 extends along the circumference of the crescent plate 4 and its cross-sectional area gradually decreases from the end of the crescent plate 4 towards the middle, when the liquid enters the tooth tip oil cavity between the outer gear 2 and the crescent plate 4 from the liquid inlet, the liquid will flow between the outer gear 2 and the crescent plate 4 through the damping groove 41. The liquid can be pre-pressurized before entering the high-pressure area through the damping groove 41. As the liquid flows to the middle of the main crescent plate 4, the width of the damping groove 41 gradually decreases, which causes the pressurization space between the damping groove 41 and the outer gear 2 to also correspondingly decrease, so that the pressure of the oil liquid can slowly and smoothly transition to the high-pressure state, ensuring that the outer gear 2 can adapt to the change of high pressure in advance when it reaches the high-pressure area, avoiding vibration and noise caused by sudden pressure change.

[0029] When the damping groove 41 is located on the upper end face of the crescent plate 4 and is adjacent to the liquid outlet, since the damping groove 41 extends along the circumference of the crescent plate 4 and its cross-sectional area gradually decreases from the end of the crescent plate 4 towards the middle, when the liquid needs to be discharged from the high-pressure area to the oil outlet, it will also pass through the damping groove 41 on the main crescent plate 4. However, the flow direction of the liquid is opposite to the pre-pressurization process, and the width of the damping groove 41 gradually increases from the middle to the end, so that the decompression space between the damping groove 41 and the inner gear 3 gradually increases. This gradually increasing decompression space allows the pressure of the oil liquid to slowly and smoothly transition to the low-pressure state, thereby ensuring that the inner gear 3 can adapt to the change of low pressure in advance when it reaches the oil outlet cavity, avoiding vibration and noise caused by sudden pressure change.

[0030] When the damping groove 41 is located at the lower end surface of the crescent plate 4 and is adjacent to the liquid outlet, since the damping groove 41 extends along the circumference of the crescent plate 4 and the cross-sectional area gradually decreases from the end of the crescent plate 4 to the middle, when the liquid needs to be discharged from the high-pressure area to the oil outlet, it will also pass through the damping groove 41 on the main crescent plate 4. But the flow direction of the liquid is opposite to the pre-pressure increasing process, the width of the damping groove 41 gradually increases from the middle to the end, so that the pressure reduction space between the damping groove 41 and the outer gear 2 gradually increases, and the gradually increasing pressure reduction space makes the pressure of the oil gradually and smoothly change to the low pressure state, thereby ensuring that the outer gear 2 can adapt to the change of low pressure in advance when reaching the oil outlet cavity, avoiding vibration and noise caused by sudden pressure change.

[0031] In the compression phase: as the gear continues to rotate, the previously inhaled liquid is enclosed in the interlocking volume formed by the outer gear 2, the inner gear 3 and the crescent plate 4, and the damping groove 41 on the crescent plate 4 performs staged attenuation on the compression wave through its variable cross-section structure. In the liquid discharge phase: when the meshing tooth pair enters the liquid discharge area, the crescent plate 4 closely cooperates with the inner gear 3 to form a high-pressure sealing band. This sealing band ensures that the liquid does not leak back to the cavity during discharge, and under the action of the high-pressure sealing band, the liquid is discharged at high pressure through the liquid outlet. The pressure compensation ring groove integrated at the rear end of the liquid outlet helps to eliminate fluid pulsation and make the discharged liquid more stable. With the continuous rotation of the gear, the liquid suction, compression and discharge stages are repeated continuously to achieve continuous pumping of the liquid.

[0032] The gear pump 100 of the embodiment of the utility model, through the damping groove 41, the pressure of the oil can be slowly and smoothly changed, the sudden change of oil pressure in the gear pump 100 is prevented, the vibration, noise and pressure fluctuation of the gear pump 100, the gear pump 100 runs more stably, and the service life of the gear pump 100 is prolonged.

[0033] In some embodiments, the crescent plate 4 includes a first crescent plate 42 and a second crescent plate 43, the first crescent plate 42 is arranged in the mounting cavity, the side of the first crescent plate 42 away from the inner gear 3 is provided with a mounting groove, the second crescent plate 43 is arranged in the mounting groove, the first crescent plate 42 abuts against the outer gear 2, and the second crescent plate 43 abuts against the inner gear 3. Specifically, as shown in Figures 1-2 the first crescent plate 42 serves as a main component, the axial section of the first crescent plate 42 is wedge-shaped, the lower end surface of the first crescent plate 42 forms a dynamic seal with the outer gear 2, the upper end surface of the first crescent plate 42 is provided with an annular dovetail groove as a mounting groove, the second crescent plate 43 is arranged in the mounting groove of the first crescent plate 42, and the upper end surface of the second crescent plate 43 forms a high-pressure sealing interface with the inner gear 3, so that the transportation efficiency of the gear pump 100 is ensured through the first crescent plate 42 and the second crescent plate 43.

[0034] In some embodiments, the end of the first crescent plate 42 is provided with a damping groove 41, which is located on the side of the first crescent plate 42 away from the outer gear 2. Specifically, as shown in Figures 1-2 the damping groove 41 is arranged on the lower end face of the first crescent plate 42, and the damping groove 41 cooperates with the outer gear 2, so that the oil can pass through the damping groove 41 for pre-pressurization or pre-depressurization when entering or leaving the high-pressure area, thereby reducing the vibration and noise of the gear pump 100 and improving the operation stability of the gear pump 100.

[0035] In some embodiments, the damping groove 41 includes a first groove formed at one end of the first crescent plate 42 and a second groove formed at the other end of the first crescent plate 42. Specifically, as shown in Figures 1-2 the first groove and the second groove are both arranged on the lower end face of the first crescent plate 42, the first groove is arranged adjacent to the liquid inlet, and the second groove is arranged adjacent to the liquid outlet, so that when the oil enters the gear pump 100 from the liquid inlet, it will first pass through the wide end of the damping groove 41, and as the oil flows to the middle of the crescent plate 4, the width of the damping groove 41 gradually decreases, causing the pressurization space to also correspondingly decrease, so that the pressure of the oil can slowly and smoothly transition to the high-pressure state, avoiding the impact caused by sudden pressure changes. Similarly, when the oil needs to be discharged from the high-pressure area to the liquid outlet, the width of the damping groove 41 gradually increases from the middle to the end, causing the depressurization space to gradually increase, so that the pressure of the oil can slowly and smoothly transition to the low-pressure state.

[0036] In some embodiments, the end of the second crescent plate 43 is provided with a damping groove 41, which is located on the side of the second crescent plate 43 away from the outer gear 2. Specifically, as shown in Figures 1-2 the damping groove 41 is arranged on the upper end face of the second crescent plate 43, and the damping groove 41 cooperates with the inner gear 3, so that the oil can pass through the damping groove 41 for pre-pressurization or pre-depressurization when entering or leaving the high-pressure area, thereby reducing the vibration and noise of the gear pump 100 and improving the operation stability of the gear pump 100.

[0037] In some embodiments, the damping groove 41 includes a third groove formed at one end of the second crescent plate 43 and a fourth groove formed at the other end of the second crescent plate 43. Specifically, as shown in Figures 1-2As shown, the third groove and the fourth groove are both arranged on the upper end surface of the second crescent plate 43, the third groove is arranged adjacent to the liquid inlet, and the fourth groove is arranged adjacent to the liquid outlet. Thus, when the oil liquid enters the gear pump 100 from the liquid inlet, it will first pass through the wide end of the damping groove 41, and as the oil liquid flows to the middle of the crescent plate 4, the width of the damping groove 41 gradually decreases, causing the pressure space to also correspondingly decrease, so that the pressure of the oil liquid can slowly and smoothly transition to a high-pressure state, avoiding the impact caused by a sudden change in pressure. Similarly, when the oil liquid needs to be discharged from the high-pressure area to the liquid outlet, the width of the damping groove 41 gradually increases from the middle to the end, so that the pressure release rate gradually increases, and the pressure of the oil liquid can slowly and smoothly transition to a low-pressure state.

[0038] In some embodiments, the shape of the inner circumferential surface of the damping groove 41 is any one of a triangle, a semicircle, a semi-ellipse, a rectangle, etc. Thus, the damping groove 41 can be selected according to the actual situation to reduce the difficulty of processing and manufacturing.

[0039] In some embodiments, the depth of the damping groove 41 gradually decreases along the end of the crescent plate 4 towards the middle of the crescent plate 4 to be flush with the end surface of the crescent plate 4. Specifically, as shown in Figures 1-2 the depth of the damping groove 41 gradually decreases along the end of the crescent plate 4 towards the middle of the crescent plate 4 to 0 cm, and the liquid flowing through the damping groove 41 makes the pressure transition more stable.

[0040] In some embodiments, the number of damping grooves 41 is multiple, and the multiple damping grooves 41 are arranged at intervals along the width of the crescent plate 4. Since a single damping groove 41 needs to bear the entire pressure transition task, it is easy to cause the local pressure gradient to be too large, therefore, multiple damping grooves 41 are distributed in space to disperse the pressure impact to different areas, forming a multi-stage buffer, and the multiple damping grooves 41 are connected through flow channels to form a networked flow path, making the oil liquid distribution more uniform, further reducing the noise of the gear pump 100, and improving the service life of the gear pump 100.

[0041] In some embodiments, the circumferential length of the damping groove 41 corresponds to a central angle that is not greater than the tooth pitch angle of the outer gear 2. Specifically, the tooth pitch angle a (a = 360° / Z, Z is the number of teeth) of the outer gear 2 defines the periodicity of gear engagement. If the central angle b of the damping groove 41 exceeds a, it will cause a single damping groove 41 to span multiple engagement periods. During the rotation of the outer gear 2, the damping groove 41 is simultaneously connected to multiple engagement cavities, causing the pressure release rate to be out of control, which will cause pressure fluctuations to superimpose, making it difficult for the pressure to stabilize after rising to the back pressure, resulting in an increase in the noise of the gear pump 100.

[0042] In the description of the utility model, it is understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the utility model.

[0043] In addition, the terms "first" and "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description of the utility model, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0044] In the utility model, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected or in communication with each other; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the internal communication or interaction relationship of two elements, unless otherwise specifically limited. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0045] In the utility model, unless otherwise specifically defined and limited, the first feature "on" or "under" the second feature can be direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Moreover, the first feature "above", "above" and "above" of the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" of the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0046] In the present application, the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" mean that the specific feature, structure, material or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms is not necessarily directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the features of different embodiments or examples described in the present application and the features of different embodiments or examples within the scope of the present application without contradiction.

[0047] Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A gear pump characterized by, The utility model relates to a liquid level control device, comprising: a housing having a chamber, a liquid inlet and a liquid outlet, the liquid inlet and the liquid outlet both communicating with the chamber so that liquid flows into the chamber through the liquid inlet and flows out through the liquid outlet; a conveying assembly comprising an outer gear, an inner gear and a crescent plate, the inner gear, the outer gear and the crescent plate are rotatably arranged in the chamber, the outer gear is rotatably arranged in the inner gear, a part of the outer gear is engaged with the inner gear, a part of the outer gear is spaced apart from the inner gear to form a mounting cavity, the crescent plate is arranged in the mounting cavity, an end of the crescent plate is provided with a damping groove, the damping groove extends along the circumference of the crescent plate and the cross-sectional area of the damping groove gradually decreases in the direction from the end of the crescent plate towards the middle of the crescent plate.

2. The gear pump of claim 1, wherein, The crescent plate comprises a first crescent plate and a second crescent plate, the first crescent plate is arranged in the mounting cavity and the side of the first crescent plate away from the inner gear is provided with a mounting groove, the second crescent plate is arranged in the mounting groove, the first crescent plate abuts against the outer gear and the second crescent plate abuts against the inner gear.

3. The gear pump of claim 2, wherein, The end of the first crescent plate is provided with the damping groove, and the damping groove is located on the side of the first crescent plate away from the outer gear.

4. The gear pump of claim 3, wherein, The damping groove comprises a first groove formed at one end of the first crescent plate and a second groove formed at the other end of the first crescent plate.

5. The gear pump according to any one of claims 2-4, characterized in that, The end of the second crescent plate is provided with the damping groove, and the damping groove is located on the side of the second crescent plate away from the outer gear.

6. The gear pump of claim 5, wherein, The damping groove comprises a third groove formed at one end of the second crescent plate and a fourth groove formed at the other end of the second crescent plate.

7. The gear pump of claim 1, wherein, The shape of the inner circumferential surface of the damping groove is any one of a triangle, a semicircle, a semi-ellipse or a rectangle.

8. The gear pump of claim 1, wherein, The depth of the damping groove gradually decreases in the direction from the end of the crescent plate towards the middle of the crescent plate to be flush with the end surface of the crescent plate.

9. The gear pump of claim 1, wherein, The number of the damping grooves is multiple, and the multiple damping grooves are spaced apart along the width of the crescent plate.

10. The gear pump of claim 1, wherein, The circumferential length of the damping groove corresponds to a central angle not greater than the tooth pitch angle of the outer gear.

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