Oil pump pressure-limiting valve and two-stage oil pump
By adding elastic damping pins and symmetrically arranged oil drain holes in the signal oil channel of the oil pump pressure limiting valve, the problem of unstable operation of the pressure limiting valve valve core and biased grinding of the valve core during low-frequency pressure fluctuations is solved, and the oil pressure stability and engine performance are achieved.
Patent Information
- Application Number
- CN202421535325.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-01
- Publication Date
- 2025-03-18
- Estimated Expiration
- 2034-07-01
AI Technical Summary
In the dual-stage oil pump, the valve core of the pressure limiting valve is unstable when the low-frequency pressure fluctuates, resulting in large fluctuations in the main oil channel, and the thin-walled engine oil filter and cooler are prone to damage. In addition, the oil drainage method of the existing pressure limiting valve is one-side oil drainage, resulting in a biased grinding of the valve core and an increase in oil leakage.
An oil pump pressure limiting valve is designed, and an elastic damping pin is added to the signal oil channel between the valve core and the main oil channel of the engine, which absorbs low-frequency pressure fluctuations through the elastic layer, and a symmetrically arranged oil drain hole is used to avoid the valve core being biased.
It effectively reduces the fluctuation of the low-frequency pressure of the oil pump, reduces the low-frequency pressure affected by the thin-walled engine oil filter and cooler, ensures the stable oil pressure of the engine main oil passage, and extends the overall performance and service life of the engine.
Smart Images
Figure CN222633289U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of oil pumps, in particular to an oil pump pressure limiting valve and a two-stage oil pump. Background Art
[0002] The two-stage oil pump has a main oil pump (i.e., main oil pump) and a secondary oil pump (i.e., secondary oil pump). The main oil pump is responsible for supplying oil to the engine body, and the secondary oil pump is responsible for supplying oil to the main oil pump. The pressure limiting valve plays a vital role in the two-stage oil pump. When the oil pump speed increases and the oil pressure increases, the valve core opens a certain degree under the action of the oil pressure, allowing the oil to flow back to the oil pan, so that the oil pressure remains constant or rises slowly.
[0003] During use, it was found that when the hydraulic oil of the oil pump produces low-frequency (less than 100Hz) pressure fluctuations, that is, when the low-frequency pressure fluctuations of the main oil channel are high, the valve core of the pressure limiting valve is unstable and fluctuates greatly, which in turn causes large fluctuations in the main oil channel, resulting in damage to the housing, filter element, and thin fins of the thin-walled oil filter. In addition, the existing two-stage oil pump pressure limiting valve has a single-side oil leakage method, which causes eccentric wear of the pressure limiting valve core and instability of the valve core movement. Moreover, the worn valve core increases the oil leakage, which leads to the problem of low oil pressure in the main oil channel of the engine. Utility Model Content
[0004] In view of the shortcomings of the prior art, the purpose of the embodiment of the utility model is to provide an oil pump pressure limiting valve, which can effectively reduce the fluctuation of the low-frequency (less than 100Hz) pressure of the oil pump, reduce the impact of low-frequency pressure on the filter and cooler, reduce the eccentric wear of the valve core, ensure the stability of the oil pressure in the main oil channel of the engine, and improve the overall performance and service life of the engine.
[0005] In order to achieve the above purpose, the embodiment of the utility model provides the following technical solutions:
[0006] A lubricating oil pump pressure limiting valve, the pressure limiting valve having a hydraulic chamber, a valve core installed in the hydraulic chamber, one end of the valve core being provided with an elastic member; an oil inlet channel and an oil drain port being provided on the side of the hydraulic chamber, a signal oil channel being provided on the end of the hydraulic chamber, the signal oil channel being located at the end of the valve core away from the elastic member, the hydraulic oil in the signal oil channel being able to push the valve core to overcome the elastic force of the elastic member and move so that the oil inlet channel and the oil drain port are connected, the oil drain ports being symmetrically arranged on the circumferential side of the valve core; an elastic damping pin being provided in the signal oil channel, the elastic damping pin comprising a damping sleeve, the inner side of which is provided with an elastic layer.
[0007] Optionally, the valve core has a connecting rod portion and a guide portion, the guide portion cooperates with the inner wall of the hydraulic chamber, and the diameter of the connecting rod portion is smaller than the diameter of the guide portion.
[0008] Optionally, an annular groove for storing oil is provided on the outer wall of the guide portion, and the end surface of the guide portion connected to the connecting rod portion is a plane.
[0009] Optionally, the valve core divides the hydraulic cavity into a plurality of chambers, the connecting rod portion and the inner wall of the hydraulic cavity form an oil drain cavity, and a screw plug is installed on the side wall of the oil drain cavity.
[0010] Optionally, the end of the valve core away from the signal oil channel is an oil drain chamber, the elastic member is installed in the oil drain chamber, a screw plug is installed at the end of the oil drain chamber, one end of the elastic member abuts against the valve core, and the other end abuts against the screw plug.
[0011] Optionally, a balancing hole is provided on the side wall of the pressure-limiting valve, the balancing hole is communicated with the hydraulic chamber, and is located at one end of the valve core where the elastic member is installed.
[0012] Optionally, the damping sleeve is made of metal, and the elastic layer is made of rubber.
[0013] The embodiment of the utility model further provides a two-stage oil pump, comprising a main oil pump, an auxiliary oil pump and the oil pump pressure limiting valve as described above.
[0014] Optionally, the main oil pump includes a first driving gear shaft, a driving gear, and a first oil inlet, an oil outlet and a first oil outlet that are connected in sequence, and the oil outlet is connected to the oil inlet of the pressure limiting valve.
[0015] Optionally, the auxiliary oil pump includes a second driving gear shaft, a driven gear shaft, a second oil inlet and a second oil outlet, and meshing gears are installed on the second driving gear shaft and the driven gear shaft.
[0016] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages:
[0017] 1. By adding an elastic damping pin in the signal oil channel between the valve core and the main oil channel of the engine, the fluctuation of the low-frequency (less than 100Hz) pressure of the gear oil pump is effectively reduced. The elastic layer on the elastic damping pin reduces the low-frequency pressure fluctuation of the signal oil through a smaller flow cross-sectional area of the signal oil. In addition, due to the elasticity of the elastic layer, when the pressure is high, the elastic layer is severely squeezed and the throttle hole is large. When the pressure is low, the rubber is lightly squeezed and the throttle hole is small, which effectively widens the pressure range of the low-frequency signal oil, so that the gear oil pump greatly reduces the low-frequency oil pressure fluctuation in the signal oil channel, reduces the influence of low-frequency pressure on the thin-walled oil filter housing and filter element, and reduces the failure rate of the oil filter.
[0018] 2. The oil pump valve core and the valve body are matched with a very small gap, and the oil drain holes are arranged symmetrically. When the oil pressure increases to overcome the spring force under the valve core, the valve core moves downward under the oil pressure until the valve core diameter becomes smaller and moves to the middle of the oil drain hole. The oil then leaks out symmetrically from the oil drain holes, causing the valve core to be subjected to symmetrical lateral pressure at the oil drain port, which can be symmetrically offset, avoiding eccentric wear between the valve core and the valve body due to unbalanced lateral pressure, and solving the problem of wear causing the gap to become larger, the leakage to increase, the oil pressure in the engine main oil channel to drop, and poor lubrication of the engine moving parts.
[0019] Additional advantages of the present invention will be given in the following description, and some will become apparent from the following description or will be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention.
[0021] Figure 1 It is a front view schematic diagram of a two-stage oil pump provided by an embodiment of the utility model;
[0022] Figure 2 It is a schematic diagram of the interior of the pressure limiting valve provided by an embodiment of the utility model;
[0023] Figure 3 It is a schematic diagram of a signal oil passage provided by an embodiment of the utility model;
[0024] Figure 4 It is a side view schematic diagram of a two-stage oil pump provided by an embodiment of the utility model;
[0025] Figure 5 It is a schematic diagram of an elastic damping pin provided in an embodiment of the utility model;
[0026] Figure 6 It is a schematic diagram of the valve core provided by the embodiment of the utility model;
[0027] Figure 7 This is a schematic diagram of the second oil outlet of the auxiliary oil pump provided in an embodiment of the utility model;
[0028] In the figure: 1, main oil pump; 11, first oil inlet; 12, first driving gear shaft; 13, driving gear; 14, oil outlet; 15, first oil outlet; 2, auxiliary oil pump; 21, second oil inlet; 22, driven gear shaft; 23, second driving gear shaft; 24, second oil outlet; 3, pressure limiting valve; 31, oil drain port; 32, valve core; 33, hydraulic chamber; 34, screw plug; 35, spring; 36, balance hole; 37, screw plug; 38, oil inlet; 39, signal oil channel; 4, safety valve; 5, elastic damping pin; 51, damping sleeve; 52, elastic layer;
[0029] In order to show the positions of various parts, the distances or sizes between them are exaggerated and the schematic diagram is for reference only. DETAILED DESCRIPTION
[0030] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.
[0031] Example 1
[0032] like Figure 1 As shown, in this embodiment, an oil pump pressure limiting valve 3 is proposed, and the pressure limiting valve 3 has a hydraulic chamber 33, such as Figure 2 As shown, a valve core 32 is installed in the hydraulic chamber 33, and an elastic member (a spring 35 is used in this embodiment) is provided at one end of the valve core 32; an oil inlet channel 38 and an oil drain port 31 are provided on the side of the hydraulic chamber 33, as shown in FIG. Figure 3 As shown, a signal oil passage 39 is provided at the end of the hydraulic chamber 33. The signal oil passage 39 is located at the end of the valve core 32 away from the elastic member. The hydraulic oil in the signal oil passage 39 can push the valve core 32 to overcome the elastic force of the elastic member and move so that the oil inlet passage 38 and the oil drain port 31 are connected. The oil drain port 31 is symmetrically arranged on the peripheral side of the valve core 32. Figure 4 As shown, in this embodiment, two oil drain ports 31 are provided. The two oil drain ports 31 are symmetrically located on both sides of the valve core 32 and are coaxial.
[0033] The signal oil passage 39 is provided with an elastic damping pin 5, such as Figure 5As shown. The elastic damping pin 5 includes a damping sleeve 51, and an elastic layer 52 is arranged on the inner side of the damping sleeve 51. The elastic damping pin 5 is a cylindrical damping element added in the signal oil passage 39 between the valve core 32 and the main oil passage of the engine. The rubber is vulcanized onto the metal element, and the rubber and the metal element form the elastic damping pin 5. The metal material of the damping sleeve 51 provides the necessary mechanical strength and durability, and the elastic layer 52 is made of rubber material to provide the required elasticity and damping characteristics, and effectively absorb the pressure fluctuation of the hydraulic oil.
[0034] By adding an elastic damping pin 5 in the signal oil passage 39 between the valve core 32 and the main oil passage of the engine, the rubber hole on the elastic damping pin 5 reduces the low-frequency pressure fluctuation of the signal oil through the smaller flow cross-sectional area of the signal oil, and the rubber on the damping element has a certain elasticity, which can effectively widen the pressure range of the low-frequency signal oil and reduce the fluctuation better. When the pressure is high, the rubber is severely squeezed and the throttle hole is large. When the pressure is low, the rubber is lightly squeezed and the throttle hole is small, so that the gear oil pump greatly reduces the low-frequency oil pressure fluctuation in the signal oil passage 39, effectively protecting the oil filter and the oil cooler.
[0035] The oil pump valve core 32 and the valve body are matched with a very small gap, and a symmetrically arranged oil drain hole is adopted. When the oil pressure increases to overcome the elastic force of the spring 35 under the valve core 32, the valve core 32 moves downward under the action of the oil pressure until the valve core 32 moves to the middle of the oil drain hole at the smaller diameter. The oil then leaks out symmetrically from the oil drain hole, causing the valve core 32 to be subjected to symmetrical lateral pressure at the oil drain port 31, which can be symmetrically offset, avoiding the valve core 32 from being subjected to unbalanced lateral pressure and eccentric wear with the valve body, and solving the problem that the gap becomes larger due to wear, the leakage volume increases, the oil pressure in the main oil channel of the engine decreases, and the engine moving parts are poorly lubricated.
[0036] like Figure 6 As shown, the valve core 32 includes a connecting rod portion (thinner part) and a guide portion (thicker part), and the guide portion cooperates with the inner wall of the hydraulic chamber 33 to ensure the stable movement of the valve core 32 in the hydraulic chamber 33. The connecting rod portion has a smaller diameter than the guide portion, and is used to connect the oil inlet passage 38 and the oil unloading port.
[0037] Furthermore, annular grooves are provided on the outer wall of the guide part, which are used to store oil to provide additional lubrication and reduce friction between the valve core 32 and the inner wall of the hydraulic chamber 33 to avoid the problem of sticking. The end surface of the guide part connecting the connecting rod part is a plane, that is, the end is a flat shoulder structure, so that the end of the valve core 32 is subjected to vertical downward pressure, avoiding the lateral force generated by the oblique shoulder at the oil inlet and causing the valve core 32 to wear eccentrically.
[0038] The guide portion of the valve core 32 divides the hydraulic chamber 33 into a plurality of chambers. The connecting rod portion and the inner wall of the hydraulic chamber 33 form an oil drain chamber, and a screw plug 34 is installed on the side wall of the oil drain chamber. The end of the valve core 32 away from the signal oil passage 39 is an oil drain chamber, and the elastic member is installed in the oil drain chamber. A screw plug 37 is installed at the end of the oil drain chamber. One end of the elastic member abuts against the valve core 32, and the other end abuts against the screw plug 37. The arrangement of the screw plug 34 and the screw plug 37 ensures the stable operation of the oil pump system and the normal operation of the valve core 32.
[0039] A balancing hole 36 is provided on the side wall of the pressure limiting valve 3. The balancing hole 36 is connected to the hydraulic chamber 33 and is located at one end of the mounting elastic member of the valve core 32. The balancing hole 36 is used to release the internal force at the lower part of the valve core 32 so that the valve core 32 can move downward under the action of the engine oil pressure.
[0040] In summary, double-sided oil leakage is adopted to make the valve core 32 evenly stressed, and the lateral force generated by the single oil leakage port 31 is avoided to cause eccentric wear of the valve core 32. The valve core 32 has multiple annular grooves to increase lubrication with the valve body and avoid sticking problems. The top of the valve core 32 is a flat shoulder structure, so that the top surface of the valve core 32 is subjected to vertical downward pressure, and the lateral force generated by the oblique shoulder of the oil inlet is avoided to cause eccentric wear of the valve core 32.
[0041] Example 2
[0042] Based on the pressure limiting valve 3 of Example 1, this embodiment proposes a two-stage oil pump, including a main oil pump 1 and an auxiliary oil pump 2. The main oil pump 1 is responsible for supplying oil to the engine body, and the auxiliary oil pump 2 is responsible for supplying oil to the main oil pump. The stable operation of the system is ensured by adjusting the pressure limiting valve 3.
[0043] like Figure 1 As shown, the main oil pump 1 is composed of a first driving gear shaft 12, a driving gear 13, and a first oil inlet 11, an oil outlet 14, and a first oil outlet 15 that are connected in sequence. The engine oil enters the main oil pump 1 through the first oil inlet 11, and flows out from the first oil outlet 15 after being acted upon by the driving gear 13 and the first driving gear shaft 12. The oil outlet 14 is connected to the oil inlet 38 of the pressure limiting valve 3. When the oil pressure in the main oil channel increases, the valve core 32 moves, and the oil inlet 38 is connected to the pressure relief port. The engine oil in the main oil channel flows back to the oil pan through the oil outlet 14, the oil inlet 38, and the oil relief port 31, thereby ensuring the normal operation of the engine under various working conditions.
[0044] like Figure 1 , Figure 7As shown, the auxiliary oil pump 2 includes a second driving gear shaft 23, a driven gear shaft 22, a second oil inlet 21 and a second oil outlet 24. The second driving gear shaft 23 and the driven gear shaft 22 are equipped with meshing gears. The auxiliary oil pump 2 sucks in the engine oil through the second oil inlet 21, and after the gears of the second driving gear shaft 23 and the driven gear shaft 22 mesh, the engine oil is discharged from the second oil outlet 24 and supplied to the main oil pump 1. This design ensures the efficient operation of the auxiliary oil pump 2 and provides a stable oil supply for the main oil pump.
[0045] The two-stage oil pump is also provided with a safety valve 4. When the oil pump is blocked, the oil pressure of the oil pump increases suddenly, and the oil pump safety valve 4 opens. The opening pressure of the safety valve 4 is much higher than that of the pressure limiting valve 3, so that the oil flows back to the oil pan.
[0046] Although the above describes the specific implementation methods of the utility model in conjunction with the accompanying drawings, it is not intended to limit the protection scope of the utility model. Technical personnel in the relevant field should understand that on the basis of the technical solution of the utility model, various modifications or deformations that can be made by technical personnel in this field without creative work are still within the protection scope of the utility model.
Claims
1. An oil pump pressure limiting valve, characterized in that: The pressure limiting valve has a hydraulic cavity, a valve core is installed in the hydraulic cavity, and an elastic member is arranged at one end of the valve core; An oil inlet channel and an oil drain port are provided on the side of the hydraulic chamber, and a signal oil channel is provided at the end of the hydraulic chamber. The signal oil channel is located at the end of the valve core away from the elastic member. The hydraulic oil in the signal oil channel can push the valve core to overcome the elastic force of the elastic member and move so that the oil inlet channel and the oil drain port are connected. The oil drain ports are symmetrically arranged on the circumference of the valve core. An elastic damping pin is arranged in the signal oil passage, and the elastic damping pin comprises a damping sleeve, and an elastic layer is arranged on the inner side of the damping sleeve.
2. The oil pump pressure limiting valve according to claim 1, characterized in that: The valve core comprises a connecting rod portion and a guiding portion, wherein the guiding portion cooperates with the inner wall of the hydraulic cavity, and the diameter of the connecting rod portion is smaller than the diameter of the guiding portion.
3. The oil pump pressure limiting valve according to claim 2, characterized in that: The outer wall of the guide portion is provided with an annular groove for storing oil, and the end surface of the guide portion connected to the connecting rod portion is a plane.
4. The oil pump pressure limiting valve according to claim 2, characterized in that: The valve core divides the hydraulic cavity into a plurality of chambers, the connecting rod portion and the inner wall of the hydraulic cavity form an oil drain cavity, and a screw plug is installed on the side wall of the oil drain cavity.
5. The oil pump pressure limiting valve according to claim 4, characterized in that: The end of the valve core away from the signal oil channel is an oil drain chamber, the elastic member is installed in the oil drain chamber, a screw plug is installed at the end of the oil drain chamber, one end of the elastic member abuts against the valve core, and the other end abuts against the screw plug.
6. The oil pump pressure limiting valve according to claim 5, characterized in that: A balancing hole is arranged on the side wall of the pressure limiting valve. The balancing hole is communicated with the hydraulic cavity and is located at one end of the valve core where the elastic member is installed.
7. The oil pump pressure limiting valve according to claim 1, characterized in that: The damping sleeve is made of metal, and the elastic layer is made of rubber.
8. A two-stage oil pump, characterized in that: It comprises a main oil pump, an auxiliary oil pump and an oil pump pressure limiting valve as described in any one of claims 1 to 7.
9. The two-stage oil pump according to claim 8, characterized in that: The main oil pump comprises a first driving gear shaft, a driving gear, and a first oil inlet, an oil outlet and a first oil outlet which are connected in sequence, and the oil outlet is connected to the oil inlet of the pressure limiting valve.
10. The two-stage oil pump according to claim 8, characterized in that: The auxiliary oil pump comprises a second driving gear shaft, a driven gear shaft, a second oil inlet and a second oil outlet, and meshing gears are mounted on the second driving gear shaft and the driven gear shaft.