Metering pump

Abstract

The utility model provides a metering pump which comprises a worm, an adjusting shaft and a worm wheel supporting sleeve, wherein the adjusting shaft and the worm wheel supporting sleeve are coaxially arranged. The adjusting shaft is inserted into an inner cavity of the worm wheel supporting sleeve, a through hole penetrating through the adjusting shaft in the vertical direction is formed in the adjusting shaft, and the lower portion of the through hole communicates with the inner cavity; the worm gear supporting sleeve is connected with the worm, a groove is formed in the outer surface of the worm gear supporting sleeve, the lower portion of the groove is communicated with the inner cavity, and the structure of the groove is arranged to enable lubricating oil making contact with the upper portion of the groove to flow downwards along the groove and be conveyed to the inner cavity through rotation of the worm gear supporting sleeve. Lubricating oil in the metering pump can only be injected to the height which submerges the eccentric shaft sleeve or submerges the worm gear, when the worm gear rotates, the lubricating oil can circularly flow along the path of the gear box, the groove and the through hole, and the lubricating oil can flow through a bearing above the worm gear in the process of overflowing from the top of the through hole and flowing back to the gear box. Therefore, the bearing is fully lubricated.

Description

Technical Field

[0001] The utility model relates to the technical field of fluid delivery pumps, in particular to a metering pump. Background Art

[0002] The long-term, uninterrupted operation of metering pumps places extremely high demands on the wear resistance of their components. High-quality materials and rigorous manufacturing processes are required to maintain stable operation. Lubrication between components is also crucial. Lubricating oil forms a protective film between mechanical components, preventing direct contact between metal parts and reducing heat and wear caused by friction. Lubricating oil also removes impurities and reduces energy consumption.

[0003] At present, the gearbox of a plunger-type metering pump is usually equipped with components such as bearings, eccentric sleeves, adjusting shafts, worm gears, worm gear support sleeves and connecting rods. Among them, under normal use, the eccentric sleeves, worm gear support sleeves, eccentric sleeves and connecting rods are arranged below the worm gear or at the same height as the worm gear, the bearings and adjusting shafts are above the worm gear, and the lubricating oil is filled in the gearbox. Since the movable space of the plunger needs to be reserved in the metering pump, the lubricating oil is usually filled to a height that covers the worm gear. The bearings above the worm gear need to rely on the worm gear rotating to stir the lubricating oil and make the lubricating oil rise to achieve lubrication. For positions far away from the worm gear, lubrication can only be achieved by splashing the lubricating oil, and its lubrication effect is poor, and the service life of the bearings is short. In contrast, the existing technology also uses grease to lubricate bearings far away from the lubricating oil immersion position, and adds oil seals to prevent the loss of grease. However, grease has the following disadvantages compared to lubricating oil:

[0004] 1) Poor fluidity: Grease is semi-solid and does not flow at room temperature. It is difficult to add grease or replace grease on friction parts, and it requires disassembly or the use of special grease injection tools;

[0005] 2) Large internal friction resistance: The stirring resistance of the grease is large, resulting in large heat generation and relatively poor cooling effect. The internal friction resistance of the grease will affect the operating efficiency of the equipment;

[0006] 3) Not suitable for high speed: Ordinary mineral oil grease is not suitable for high speed, and its allowable speed is limited;

[0007] 4) Poor heat dissipation effect: Since grease cannot take away some of the heat like lubricating oil, its heat dissipation effect is relatively poor;

[0008] 5) Oil seal is easy to wear: Oil seal is a wearing part. If the oil seal is damaged and grease is lost, the bearing will easily burn due to insufficient lubrication. Utility Model Content

[0009] The technical problem to be solved by the utility model is to provide a metering pump in order to overcome the defect of poor lubrication effect inside the metering pump in the prior art.

[0010] The utility model solves the above technical problems through the following technical solutions:

[0011] A metering pump comprises a worm, a coaxially arranged worm gear support sleeve and an adjusting shaft, wherein the adjusting shaft is inserted into the inner cavity of the worm gear support sleeve:

[0012] The adjusting shaft has a through hole extending vertically through the adjusting shaft, and the lower portion of the through hole is in communication with the inner cavity;

[0013] The worm gear support sleeve is connected to the worm, and has a groove on its outer surface, the lower portion of which is connected to the inner cavity. The structure of the groove is configured so that the lubricating oil in contact with the upper portion of the groove can flow downward along the groove and be delivered to the inner cavity through the rotation of the worm gear support sleeve.

[0014] In this technical solution, the lubricating oil in the metering pump can be filled only to a height that covers the eccentric sleeve. By setting a through hole inside the adjusting shaft and a groove on the worm gear support sleeve, when the worm gear rotates, the lubricating oil can circulate along the path of the gear box, the groove, and the through hole. In the process of the lubricating oil overflowing from the top of the through hole and flowing back to the gear box, it will flow through the bearing above the worm gear, thereby achieving sufficient lubrication of the bearing.

[0015] Preferably, the groove extends spirally upward from the bottom of the worm gear support sleeve along the rotation direction of the worm gear support sleeve.

[0016] The present technical solution provides a specific arrangement of grooves. Specifically, when the worm gear support sleeve rotates rapidly due to external power input, the lubricating oil in the grooves can fully lubricate the outer circumference of the worm gear support sleeve. Since the grooves spirally extend upward from the bottom of the worm gear support portion in the direction of rotation of the worm gear support sleeve, when the worm gear support sleeve rotates rapidly, the lubricating oil lags behind the worm gear support sleeve due to inertia. At the same time, the sidewalls of the grooves transmit the rotational torque to the lubricating oil. Combined with the gravity and inertia of the lubricating oil and the torque transmitted by the sidewalls of the grooves, the lubricating oil flows downward along the grooves to the bottom of the worm gear support sleeve, then flows into the inner cavity of the worm gear support sleeve and rises along the through hole in the adjustment shaft until it overflows from the top of the through hole. After overflowing, the lubricating oil flows downward through the bearings, fully lubricating the bearings, and then flows back into the gearbox and into the grooves, repeating this cycle, thereby achieving a circulating flow of the lubricating oil.

[0017] Preferably, along the circumference of the worm gear support sleeve, an extension range of the groove on the outer circumference side of the worm gear support sleeve is greater than or equal to one quarter of the outer circumference side of the worm gear support sleeve.

[0018] In the present technical solution, by setting the extension range of the groove on the outer peripheral side of the worm gear support sleeve to be greater than or equal to one quarter of the outer peripheral side of the worm gear support sleeve along the circumference of the worm gear support sleeve, it is avoided that the side wall of the groove has insufficient force on the downward flow of the lubricating oil, resulting in the lubricating oil flowing downward too slowly.

[0019] Preferably, along the circumference of the worm gear support sleeve, an extension range of the groove on the outer circumference side of the worm gear support sleeve is less than or equal to half of the outer circumference side of the worm gear support sleeve.

[0020] By setting the extension range of the groove on the outer peripheral side of the worm gear support sleeve to be less than or equal to half of the outer peripheral side of the worm gear support sleeve along the circumferential direction of the worm gear support sleeve, it is avoided that the flow path of the lubricating oil in the groove is too long, which causes the lubricating oil to flow downward too slowly.

[0021] Preferably, the number of the grooves is a, and a≥2.

[0022] In this technical solution, by setting the number of grooves to be greater than or equal to two, the lubricating oil has sufficient paths to flow downward.

[0023] Preferably, the number of the grooves is a, and a≤5.

[0024] In this technical solution, by setting the number of grooves to be less than or equal to five, five grooves or less are sufficient to allow the lubricating oil to flow downward, thus avoiding excessive processing and increasing costs.

[0025] Preferably, the metering pump further comprises a worm gear, wherein the worm gear is connected to the worm, and the worm gear is connected to the worm gear support sleeve.

[0026] Since the outer peripheral side of the worm wheel and the inner peripheral side of the worm wheel support sleeve are in contact with each other in the prior art, compared with connecting the worm wheel support sleeve to the external power of the worm wheel separately, in this technical solution, the purpose of synchronous movement of the worm wheel support sleeve and the worm wheel is achieved by changing the worm wheel and the worm wheel support sleeve to be connected. The structural changes to the worm wheel and the worm wheel support sleeve are relatively small, and there is no need to formulate a new processing plan. Only the original plan needs to be improved. The processing is simpler and more convenient, and the manufacturing cost is reduced.

[0027] Preferably, the metering pump further comprises a bolt, the worm gear and the worm gear support sleeve are provided with threaded holes with matching positions, and the bolt is arranged in the threaded hole to connect the worm gear and the worm gear support sleeve.

[0028] In this technical solution, a method for fixing and connecting the worm gear and the worm gear support sleeve is provided. The worm gear and the worm gear support sleeve are fixedly connected by using bolts, and the structure is simple and reliable.

[0029] Preferably, the adjusting shaft is connected to the worm gear support sleeve.

[0030] In this technical solution, compared with directly connecting the adjusting shaft to external power, the purpose of synchronous movement of the adjusting shaft and the worm gear is indirectly achieved by connecting the worm gear support sleeve that moves synchronously with the worm gear to the adjusting shaft, and the structural setting is simpler and more convenient.

[0031] Preferably, the outer circumference of the adjusting shaft abuts against the inner circumference of the worm gear support sleeve;

[0032] The metering pump further includes a connecting block. The outer peripheral side of the adjusting shaft has a first groove extending in the vertical direction. The worm gear support sleeve has a second groove extending in the vertical direction. The connecting block is embedded in the first and second grooves.

[0033] In this technical solution, a method for fixing the worm gear and the worm gear support sleeve in the circumferential direction is provided, by respectively setting a first groove and a second groove on the outer circumferential side of the adjusting shaft and the inner circumferential side of the worm gear support sleeve, and embedding a connecting block in the first groove and the second groove to achieve the purpose of enabling the adjusting shaft and the worm gear support sleeve to rotate synchronously. The structure is simple and convenient.

[0034] Preferably, the first groove does not extend to the bottom of the adjusting shaft in the vertical direction, so that a bottom wall is formed at the lowest point of the first groove; the second groove extends from the top of the worm gear support sleeve to the bottom of the worm gear support sleeve in the vertical direction.

[0035] In the present technical solution, the first groove is set to not extend vertically to the bottom of the adjusting shaft, so that a bottom wall is formed at the lowest point of the first groove. The bottom wall can limit the connecting block from moving downward. During installation, the connecting block is first embedded in the first groove, and then the adjusting shaft with the embedded connecting block is inserted into the worm gear support sleeve and the second groove of the connecting block, thereby realizing the installation of the adjusting shaft and the worm gear support sleeve.

[0036] Preferably, the metering pump further comprises an end cover, and the outer circumference of the worm gear support sleeve is clearance-matched with the inner circumference of the end cover.

[0037] In this technical solution, the end cover and the worm gear support sleeve are arranged to be clearance-fitted, so that the rotation of the worm gear support sleeve is smoother.

[0038] Preferably, the radius of the through hole is r, r ≥ 2.5 mm;

[0039] In this technical solution, by setting the radius of the through hole to be greater than or equal to 3 mm, the lubricating oil overflowing from the through hole can meet the amount of oil required for sufficient lubrication of the bearing.

[0040] Preferably, the radius of the through hole is r, and r≤10 mm.

[0041] By setting the radius of the through hole to be less than or equal to 10 mm, it is prevented that the through hole is too large, resulting in the thrust provided by the worm gear support sleeve groove being unable to push excess lubricating oil out from the top of the adjustment shaft.

[0042] Preferably, the metering pump further comprises a plunger, and when the stroke of the plunger is 0%, the distance between the bottom wall of the adjustment shaft and the lowest point of the inner cavity along the vertical direction is h, and h≥3 cm.

[0043] In this technical solution, the distance between the bottom wall of the adjusting shaft and the lowest point of the inner cavity of the worm gear support sleeve is set to be greater than or equal to 5 cm, that is, a section of the cavity flows out at the bottom of the inner cavity of the worm gear support sleeve, which has a buffering effect on the lubricating oil.

[0044] The positive progressive effect of the present invention is that by providing a through hole inside the adjusting shaft and a groove on the worm gear support sleeve, when the worm gear rotates, the lubricating oil can circulate along the path of the gear box, the groove and the through hole. In the process of the lubricating oil overflowing from the top of the through hole and flowing back to the gear box, it will flow through the bearing above the worm gear, thereby achieving sufficient lubrication of the bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 The figure is a schematic diagram of the three-dimensional structure of a metering pump according to an embodiment of the present invention.

[0046] Figure 2 This is a schematic front view of a metering pump according to an embodiment of the present invention.

[0047] Figure 3 for Figure 2 Schematic diagram of the AA cross-section structure.

[0048] Figure 4 This is a schematic structural diagram of the adjusting shaft, worm gear and end cover according to an embodiment of the present invention.

[0049] Figure 5A for Figure 4 Schematic diagram of the BB cross-section structure.

[0050] Figure 5B Schematic diagram of the flow path of the lubricating fluid according to an embodiment of the present invention.

[0051] Figure 6This is an exploded schematic diagram of the adjusting shaft, worm gear, worm gear support sleeve and end cover of one embodiment of the utility model.

[0052] Figure 7 This is a schematic diagram of the three-dimensional structure of the adjusting shaft and the worm gear support sleeve according to an embodiment of the present utility model.

[0053] Figure 8 This is a schematic diagram of the three-dimensional structure of an adjustment shaft according to an embodiment of the present invention.

[0054] Figure 9 This is a schematic cross-sectional view of an adjustment shaft according to an embodiment of the present invention.

[0055] Figure 10 This is a schematic diagram of the three-dimensional structure of a worm gear support sleeve according to an embodiment of the present invention.

[0056] Description of reference numerals:

[0057] Metering pump 100

[0058] Gearbox 1

[0059] Adjustment axis 2

[0060] Through hole 21

[0061] First groove 22

[0062] Eccentric sleeve 3

[0063] Worm gear 4

[0064] Worm gear support sleeve 5

[0065] Inner cavity 51

[0066] Groove 52

[0067] End cap 6

[0068] Bolt 7

[0069] Connection block 8

[0070] Bearing 9

[0071] Worm 10 DETAILED DESCRIPTION

[0072] A preferred embodiment is given below, and the present invention is described more clearly and completely in conjunction with the accompanying drawings.

[0073] like Figures 1-10As shown, this embodiment provides a metering pump 100, which includes a gearbox 1, a worm 10, two coaxial bearings 9, an adjusting shaft 2, an eccentric sleeve 3, a worm wheel 4, a worm wheel support sleeve 5, and an end cover 6. The worm 10 is used to connect to an external power source. The adjusting shaft 2 is inserted into the inner cavity 51 of the worm wheel support sleeve 5. The adjusting shaft 2 has a through hole 21 that passes through the adjusting shaft 2 in a vertical direction. The lower part of the through hole 21 is connected to the inner cavity 51; the worm wheel support sleeve 5 is connected to the worm 10, and a groove 52 is provided on the outer surface of the worm wheel support sleeve 5. The lower part of the groove 52 is connected to the inner cavity 51. The structure of the groove 52 is configured so that the lubricating oil in contact with the upper part of the groove 52 can flow downward along the groove 52 and be transported to the inner cavity 51 through the rotation of the worm wheel support sleeve 5. The lubricating oil in the metering pump 100 can be filled only to a height that covers the eccentric sleeve 3 or the worm gear 4. By setting a through hole 21 inside the adjusting shaft 2 and a groove 52 on the worm gear support sleeve 5, when the worm gear 4 rotates, the lubricating oil can circulate along the path of the gear box 1, the groove 52, and the through hole 21. In the process of the lubricating oil overflowing from the top of the through hole 21 and flowing back to the gear box 1, it will flow through the bearing 9 above the worm gear 4, thereby achieving sufficient lubrication of the bearing 9. The specific flow path of the lubricating oil is as follows: Figure 5B As shown, Figure 5B The direction indicated by the arrow is the approximate path of lubricating oil flow.

[0074] Specifically, in this embodiment, the worm gear support sleeve 5 being connected to the worm 10 means that the worm gear support sleeve 5 can rotate with the shaft when external power is input through the worm 10. As the lubricating oil flows downward under the action of the continuous rotation of the worm gear support sleeve 5 and flows into the inner cavity 51 of the worm gear support sleeve 5, the pressure of the lubricating oil in the inner cavity 51 increases, causing the lubricating oil to rise along the through hole 21 in the adjusting shaft 2 until it overflows from the top of the adjusting shaft 2. In other words, while the groove 52 serves as a path for the lubricating oil to flow downward, the continuously rotating worm gear support sleeve 5 also provides the power source for the lubricating oil to continuously rise in the through hole 21.

[0075] Specifically in this embodiment, Figure 6 、 Figure 7 and Figure 10As shown, the groove 52 extends spirally upward from the bottom of the worm gear support sleeve 5 along the rotation direction of the worm gear support sleeve 5. At the same time, the bottom of the worm gear support sleeve 5 is also formed with a groove extending radially along the worm gear support sleeve 5. The groove connects the lower part of the groove 52 with the inner cavity 51 of the worm gear support sleeve 5. When the metering pump 100 is in a stationary state, the lubricating oil flows through the groove 52 to the inner cavity 51 of the worm gear support sleeve 5 and flows into the through hole 21 inside the adjusting shaft 2. At this time, the oil level of the lubricating oil inside the entire metering pump 100 is consistent. When the metering pump 100 is working, that is, when the external power input causes the worm gear support sleeve 5 to rotate rapidly, the lubricating oil in the groove 52 can fully lubricate the outer peripheral side of the worm gear support sleeve 5, and because the groove 52 extends spirally upward from the bottom of the worm gear 4 support portion along the rotation direction of the worm gear support sleeve 5, that is to say, as Figure 3 、 Figure 5A and Figure 6 As shown, when the worm gear support sleeve 5 rotates rapidly, the lubricating oil will lag behind the worm gear support sleeve 5 due to inertia. At the same time, the side wall of the groove 52 will transmit the rotational torque to the lubricating oil. Combined with the gravity and inertia of the lubricating oil and the torque transmitted by the side wall of the groove 52, the lubricating oil flows downward along the groove 52 to the bottom of the worm gear support sleeve 5, and then flows into the inner cavity 51 of the worm gear support sleeve 5 and rises along the through hole 21 in the adjusting shaft 2 until it overflows from the top of the through hole 21. After overflowing, the lubricating oil flows through the bearing 9 in the process of flowing downward, fully lubricating the bearing 9, and then flows back to the gear box 1 and flows into the groove 52. This reciprocating cycle realizes the circulation of the lubricating oil.

[0076] Specifically, if Figure 6 、 Figure 7 and Figure 10 As shown, along the circumference of the worm gear support sleeve 5, the groove 52 preferably extends over a range greater than or equal to one-quarter of the outer circumference of the worm gear support sleeve 5 and less than or equal to half of the outer circumference of the worm gear support sleeve 5. In other words, the central angle corresponding to the vertical projection of the groove 52 should be between 90° and 180°. By setting the groove 52's extension range greater than or equal to one-quarter of the outer circumference of the worm gear support sleeve 5 along the circumference of the worm gear support sleeve 5, insufficient force exerted by the sidewalls of the groove 52 on the downward flow of the lubricating oil, which could result in slow downward flow of the lubricating oil, is avoided. By setting the groove 52's extension range less than or equal to half of the outer circumference of the worm gear support sleeve 5 along the circumference of the worm gear support sleeve 5, an excessively long flow path of the lubricating oil in the groove 52, which could result in slow downward flow of the lubricating oil, is avoided.

[0077] Specifically in this embodiment, the extension range of the groove 52 on the outer circumference of the worm gear support sleeve 5 is equal to one third of the outer circumference of the worm gear support sleeve 5 .

[0078] Meanwhile, the number of grooves 52 on the worm gear support sleeve 5 is preferably 2, 3, 4, or 5. By setting the number of grooves 52 to be greater than or equal to two, the lubricating oil has sufficient paths to flow downward. By setting the number of grooves 52 to be less than or equal to five, less than five grooves 52 are sufficient for the lubricating oil to flow downward, avoiding excessive processing and increased costs.

[0079] Specifically in this embodiment, Figure 6 、 Figure 7 and Figure 10 As shown, there are three grooves 52 .

[0080] like Figure 3 and Figure 5A As shown, the worm wheel 4 is directly connected to the worm 10, and the worm wheel 4 is connected to the worm support sleeve 5. That is to say, in this embodiment, the worm 10 directly drives the worm wheel 4, and the worm support sleeve 5 is connected to the worm 10 through the worm wheel 4. Since the worm wheel 4 is directly connected to the worm 10 in the prior art, the outer peripheral side of the worm wheel 4 and the inner peripheral side of the worm support sleeve 5 are in contact with each other, and the top of the worm support sleeve 5 is also in contact with the worm wheel 4. Compared with connecting the worm support sleeve 5 to the external power of the worm wheel 4 separately, the purpose of the worm support sleeve 5 and the synchronous movement is achieved by changing the worm wheel 4 and the worm support sleeve to be connected. The structural changes to the worm wheel 4 and the worm support sleeve 5 are relatively small, and there is no need to formulate a new processing plan. It is only necessary to improve the original plan, which makes processing simpler and more convenient, and reduces manufacturing costs.

[0081] Of course, in other embodiments, the worm gear support sleeve 5 may also be directly connected to the worm, so as to achieve the purpose of making the worm gear support sleeve rotate quickly when external power is input, which will not be repeated here.

[0082] Specifically, if Figure 3 and Figure 5A As shown, in this embodiment, the metering pump 100 further includes a bolt 7. The worm gear 4 and the worm gear support sleeve 5 have matching threaded holes, and the bolt 7 is disposed in the threaded hole to connect the worm gear 4 and the worm gear support sleeve 5. In other words, the worm gear 4 and the worm gear support sleeve 5 are connected by the bolt 7. The use of the bolt 7 to securely connect the worm gear 4 and the worm gear support sleeve 5 provides a simple and reliable structure.

[0083] Of course, in other embodiments, the worm gear 4 and the worm gear support sleeve 5 may also be connected using other methods in the prior art to achieve the purpose of the worm gear support sleeve 5 being able to rotate synchronously with the worm gear 4, which will not be repeated here.

[0084] At the same time, if Figure 3 、 Figure 6 、 Figure 7 and Figure 8 As shown, the adjusting shaft 2 is connected to the worm gear support sleeve 5. That is, in this embodiment, the adjusting shaft 2 is not directly connected to the worm 10, but is connected to the worm 10 through the worm gear support sleeve 5. Compared to directly connecting the adjusting shaft 2 to an external power source, indirectly connecting the worm gear support sleeve 5, which moves synchronously with the worm gear 4, to the adjusting shaft 2 achieves synchronous movement of the adjusting shaft 2 and the worm gear, resulting in a simpler and more convenient structural arrangement.

[0085] Of course, in other embodiments, the adjusting shaft may be directly connected to the worm, so as to achieve the purpose of making the worm gear support sleeve rotate quickly when external power is input, which will not be described in detail here.

[0086] In this embodiment, the metering pump 100 further includes a connecting block 8. The outer circumference of the adjusting shaft 2 abuts the inner circumference of the worm gear support sleeve 5. The outer circumference of the adjusting shaft 2 has a first groove 22 extending in the vertical direction, and the worm gear support sleeve 5 has a second groove 53 extending in the vertical direction. The connecting block 8 is embedded in the first groove 22 and the second groove 53. By providing the first groove 22 and the second groove 53 on the outer circumference of the adjusting shaft 2 and the inner circumference of the worm gear support sleeve 5, respectively, and embedding the connecting block 8 in the first groove 22 and the second groove 53, the adjusting shaft 2 and the worm gear support sleeve 5 can rotate synchronously, that is, the adjusting shaft 2 and the worm gear 4 can rotate synchronously, and the structure is simple and convenient.

[0087] Of course, in other embodiments, the adjusting shaft 2 and the worm gear support sleeve 5 can also be connected using other methods in the prior art to achieve the purpose of the adjusting shaft 2 being able to rotate synchronously with the worm gear support sleeve 5 and the worm wheel 4, which will not be repeated here.

[0088] In this embodiment, the first groove 22 does not extend vertically to the bottom of the adjusting shaft 2, so that a bottom wall is formed at the lowest point of the first groove 22, while the second groove 53 extends vertically from the top of the worm gear support sleeve 5 to the bottom of the worm gear support sleeve 5. By setting the first groove 22 not to extend vertically to the bottom of the adjusting shaft 2, so that a bottom wall is formed at the lowest point of the first groove 22, the bottom wall can prevent the connecting block 8 from moving downward. During installation, the connecting block 8 is first embedded in the first groove 22, and then the adjusting shaft 2 with the embedded connecting block 8 is inserted into the worm gear support sleeve 5. The connecting block 8 is inserted into the second groove 53, thereby completing the installation of the adjusting shaft 2 and the worm gear support sleeve 5.

[0089] Of course, in other embodiments, the second groove 53 may be configured not to extend to the bottom of the worm gear support sleeve 5, so that a bottom wall is formed at the lowest point of the second groove 53, and the first groove 22 is extended to the top of the adjustment shaft 2. During installation, the connecting hole is first embedded in the second groove 53. Alternatively, in more embodiments, the connecting block 8 may be integrally formed with the adjustment shaft 2, which will not be described in detail here.

[0090] In this embodiment, if Figures 3 to 6 As shown, the outer circumference of the worm gear support sleeve 5 and the inner circumference of the end cover 6 are clearance-fitted. Since the worm gear support sleeve 5 rotates continuously while the end cover 6 remains stationary during operation of the metering pump 100, the clearance-fitting of the end cover 6 and the worm gear support sleeve 5 allows for smoother rotation of the worm gear support sleeve 5.

[0091] The radius r of the through hole 21 in the adjustment shaft 2 can be in the range of 2.5 mm ≤ r ≤ 10 mm. The radius of the through hole 21 can be set to be greater than or equal to 2.5 mm so that the lubricating oil overflowing from the through hole 21 meets the amount required for adequate lubrication of the bearing 9. Furthermore, by setting the radius of the through hole 21 to be less than or equal to 10 mm, the through hole 21 is prevented from being too large, thereby preventing the thrust provided by the groove 52 of the worm gear support sleeve 5 from being unable to push the excess lubricating oil out of the top of the adjustment shaft 2.

[0092] Specifically, in this embodiment, the radius r of the through hole 21 in the adjustment shaft 2 is 8.5 mm. By setting the radius of the through hole 21 to 8.5 mm, on the one hand, the through hole 21 with a radius of 8.5 mm is less difficult to process than the through hole 21 with a radius of less than 5 mm, and can provide sufficient oil for the bearing 9.

[0093] Of course, in other embodiments, the radius of the through hole 21 can be set to any value between 2.5 mm and 10 mm according to requirements, which will not be repeated here.

[0094] In this embodiment, the metering pump further comprises a plunger. By moving the adjusting shaft 2 in the vertical direction, the eccentricity can be adjusted, thereby changing the stroke length of the plunger. When the plunger stroke is 0%, the adjusting shaft is at the lowest point. Figure 3 and Figure 5A Figure 3 Figure 5A Figure 3 Figure 6 Figure 7 Figure 8 Figures 3 to 6 Figure 3 Figure 5A As shown, when the plunger stroke is 0%, that is, when the adjustment shaft 2 is at its lowest point, the bottom of the through hole 21 is still connected to the inner cavity 51 of the worm gear support sleeve 5. Therefore, the bottom wall of the adjustment shaft 2 should be above the lowest point of the inner cavity 51. This allows a portion of space at the bottom of the inner cavity 51 to flow through and provide a certain buffering effect on the lubricating oil. Specifically, when the plunger stroke is 0%, the vertical distance h between the bottom wall of the adjustment shaft 2 and the lowest point of the inner cavity 51 can be set to be greater than or equal to 3 cm.

[0095] Specifically in this embodiment, h is set to 5 mm.

[0096] Of course, in other embodiments, h can also be set to any value greater than 3 cm, which will not be repeated here.

[0097] Although specific embodiments of the present invention have been described above, those skilled in the art will appreciate that these are merely illustrative and that the scope of protection of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, and such changes and modifications are intended to fall within the scope of protection of the present invention.

Claims

1. A metering pump comprising a worm and a coaxially arranged worm gear support sleeve and an adjusting shaft, wherein the adjusting shaft is inserted into the inner cavity of the worm gear support sleeve, characterized in that: The adjusting shaft has a through hole extending vertically through the adjusting shaft, and the lower portion of the through hole is in communication with the inner cavity; The worm gear support sleeve is connected to the worm, and has a groove on its outer surface, the lower portion of which is connected to the inner cavity. The structure of the groove is configured so that the lubricating oil in contact with the upper portion of the groove can flow downward along the groove and be delivered to the inner cavity through the rotation of the worm gear support sleeve.

2. The metering pump according to claim 1, wherein The groove spirally extends upward from the bottom of the worm gear support sleeve along the rotation direction of the worm gear support sleeve.

3. The metering pump according to claim 2, wherein Along the circumference of the worm gear support sleeve, the extension range of the groove on the outer circumference side of the worm gear support sleeve is greater than or equal to one quarter of the outer circumference side of the worm gear support sleeve; And / or, along the circumference of the worm gear support sleeve, an extension range of the groove on the outer circumference of the worm gear support sleeve is less than or equal to half of the outer circumference of the worm gear support sleeve.

4. The metering pump according to claim 2, wherein The number of the grooves is a, a≥2; And / or, the number of the grooves is a, a≤5.

5. The metering pump according to claim 1, wherein The metering pump further comprises a worm gear connected to the worm, and the worm gear is connected to the worm support sleeve.

6. The metering pump according to claim 5, wherein The metering pump further comprises a bolt. The worm gear and the worm gear support sleeve are provided with threaded holes with matching positions. The bolt is arranged in the threaded holes to connect the worm gear and the worm gear support sleeve.

7. The metering pump according to claim 1, wherein The adjusting shaft is connected to the worm gear support sleeve.

8. The metering pump according to claim 7, wherein The outer circumference of the adjusting shaft abuts against the inner circumference of the worm gear support sleeve; The metering pump further includes a connecting block. The outer peripheral side of the adjusting shaft has a first groove extending in the vertical direction. The worm gear support sleeve has a second groove extending in the vertical direction. The connecting block is embedded in the first and second grooves.

9. The metering pump according to claim 8, wherein The first groove does not extend to the bottom of the adjusting shaft in the vertical direction, so that a bottom wall is formed at the lowest point of the first groove; the second groove extends from the top of the worm gear support sleeve to the bottom of the worm gear support sleeve in the vertical direction.

10. The metering pump according to claim 1, wherein The metering pump further includes an end cover, and the outer circumference of the worm gear support sleeve is clearance-matched with the inner circumference of the end cover.

11. The metering pump according to claim 1, wherein The radius of the through hole is r, r≥2.5mm; And / or, the radius of the through hole is r, r≤10 mm.

12. The metering pump according to claim 1, wherein The metering pump further includes a plunger. When the stroke of the plunger is 0%, the distance between the bottom wall of the adjustment shaft and the lowest point of the inner cavity along the vertical direction is h, and h is ≥ 3 cm.

Images