Electronic control of continuously variable transmission oil circuit arrangement

Abstract

The utility model discloses an electronic control infinitely variable speed oil way arrangement relates to mechanical drive and control technical field, including left box body and right box body, be equipped with the oil hole on the main oil way on right box body, be equipped with the first oil channel hole of one end opening on right box body, be equipped with the second oil channel hole of one end opening on left box body, and the first oil channel hole and second oil channel hole splice and constitute the oil channel, the oil hole and first oil channel hole intercommunication, and the second oil channel hole passes through the oil hole intercommunication of connecting chamber and gear shaft, and right box body is equipped with a plurality of oil return holes at the gear below. Simplify the oil way structure, realized the oil way closed loop, in the promotion lubrication efficiency, system reliability, while, the improvement model flexibility and cost control are given full play to.

Description

Technical Field

[0001] This utility model belongs to the field of mechanical transmission and control technology, specifically relating to an electronically controlled continuously variable transmission oil circuit layout. Background Technology

[0002] In existing hybrid vehicles, the traditional engine lubrication circuit uses a multi-channel, multi-valve structure, requiring independent branches between the cylinder block, cylinder head, crankshaft, camshaft, and turbocharger, supplemented by an oil pump, pressure regulating valve, cooler, filter, and more than ten sealing interfaces. This arrangement is problematic in transverse platforms with limited space, resulting in intricate piping, numerous joints, complex assembly processes, and a high risk of leakage. If the engine displacement is upgraded or a new combustion system is installed, the lubrication requirements change, and the original oil circuit routing, oil pressure calibration, and cooling capacity must be adjusted accordingly. This necessitates modifications to the valve body, oil passages, and even cylinder block molds, leading to long verification cycles and high mold costs. Furthermore, the traditional oil circuit lacks a unified design for the cooling and lubrication of the E-CVT electric drive unit, requiring the hybrid system to add an electric oil pump and auxiliary oil tank, further increasing the number of parts and the overall vehicle weight, which is detrimental to platformization and weight reduction.

[0003] Chinese Patent Publication No. CN114165311B, Publication Date: April 19, 2024, discloses a Chinese patent entitled "A Lubricating Oil Circuit for a VVT Engine Cylinder Head," which includes a main oil circuit and a transverse oil circuit connected to the main oil circuit. The transverse oil circuit is located below a first longitudinal oil circuit and a second longitudinal oil circuit. Lubricating oil supplied by the main oil circuit flows in the transverse oil circuit in two directions: towards the first VVT inlet circuit and the second VVT inlet circuit. The first VVT inlet circuit is connected to an annular oil groove of the first camshaft journal, and lubricating oil flows through the annular oil groove into the inlet pipe of the first longitudinal oil circuit, which is connected to it, thus providing lubricating oil for the VVT. Furthermore, the annular oil groove of the first camshaft journal is connected to the inlet pipe of the first longitudinal oil circuit, and the inlet pipe of the first longitudinal oil circuit is connected to the first longitudinal oil circuit. The first longitudinal oil circuit is connected to a first tappet mounting hole and a first camshaft journal oil supply circuit. This oil circuit layout is complex and difficult to modify. Utility Model Content

[0004] This invention provides an electronically controlled continuously variable transmission (CVT) oil circuit layout that simplifies the oil circuit structure, requires minimal changes to the lubrication system when modifying an ECVT, and achieves a closed-loop oil circuit.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: an electronically controlled continuously variable transmission (CVT) oil circuit arrangement, comprising a left housing and a right housing, wherein the main oil passage on the right housing is provided with an oil intake hole, the right housing is provided with a first oil passage hole with one end open, and the left housing is provided with a second oil passage hole with one end open, the first oil passage hole and the second oil passage hole being joined together to form an oil intake passage; the oil intake hole and the first oil passage hole are connected, and the second oil passage hole is connected to the oil collection hole on the gear shaft through a connecting cavity, and the right housing is provided with several oil return holes below the gear.

[0006] Preferably, the oil sampling port and the oil sampling section are connected and vertically arranged. This vertical arrangement reduces bends in the oil path, lowers oil flow resistance, and improves oil flow efficiency. The vertical structure facilitates machining and assembly, reduces machining errors, and improves production efficiency. It also reduces the risk of leakage due to complex oil paths, improving the overall reliability of the system. When modifying the ECVT, only the depth of the oil sampling port needs to be adjusted; there is no need to redesign the oil path, significantly reducing the workload.

[0007] Preferably, the oil intake section is connected to one end of the first oil passage hole, and the oil intake section is perpendicular to the first oil passage hole and extends beyond the end of the first oil passage hole. The extended part can also serve as a sealing structure, reducing the use of additional seals and lowering costs and leakage risks. The use of connecting parts is reduced, resulting in a simpler overall structure that facilitates maintenance and repair.

[0008] Preferably, the end of the second oil passage is provided with a steering cavity, which is rectangular. The rectangular cavity is easy to form directly by CNC machining or casting, reducing a machining process compared to an arc-shaped cavity; its large volume allows it to act as a "buffer chamber" under alternating hot and cold conditions, suppressing oil pressure pulses and reducing NVH (noise, vibration, and harshness). This reduces system failures caused by oil pressure fluctuations and improves the overall reliability of the system.

[0009] Preferably, the steering cavity and the connecting cavity are connected, with the connecting cavity inclined towards the gear shaft. This inclined arrangement utilizes gravity and centrifugal force to accelerate oil flow to the gear shaft, improving lubrication efficiency, especially under high-speed conditions. The inclined design reduces the detour of the oil passages, making the overall structure more compact and saving space. It also reduces oil flow lag, resulting in faster lubrication response and adaptability to rapidly changing operating conditions.

[0010] Preferably, an oil outlet is provided at the end of the connecting cavity near the gear shaft, with the oil outlet facing the oil collection hole. The oil outlet and the oil collection hole are designed to be concentric, eliminating oil churning losses caused by lateral injection.

[0011] Preferably, the oil return hole is connected to the bottom of the tank and connected to the main oil passage via an oil pump to achieve a closed-loop oil circuit. Two oil return holes are preferably provided.

[0012] Preferably, several oil return holes are connected to the main oil passage to achieve a closed-loop oil circuit. The oil forms a short circulation within the tank, effectively reducing oil temperature and extending oil life through natural cooling or auxiliary cooling devices. The closed-loop oil circuit can automatically adjust the oil flow rate according to operating conditions, eliminating the need for external adjustment devices and improving system adaptability. It reduces lubrication failures caused by insufficient oil, improving the overall reliability of the system. The closed-loop oil circuit reduces external piping, lowering maintenance costs and leakage risks.

[0013] Preferably, the connecting cavity and the oil intake channel are arranged perpendicularly. This vertical intersection of oil channels reduces the need for multi-layer drilling, lowering processing difficulty and cost. The intersection naturally creates a throttling effect, reducing oil flow fluctuations and improving lubrication stability. The vertical arrangement also reduces the detours in the oil path, optimizes the internal space of the housing, and improves space utilization.

[0014] Preferably, the oil inlet is located on one side of the gear shaft. Single-sided oil inlet forms a wedge-shaped oil film, improving the bearing's load-bearing capacity and reducing wear. The oil flows directly to the lubrication point, reducing the flow path and resulting in a faster lubrication response.

[0015] Beneficial Effects: The electronically controlled continuously variable transmission (CVT) oil circuit layout of this utility model significantly improves the overall performance and reliability of the system through optimized oil circuit structure. The simplified oil circuit design reduces oil passage bends and the number of parts, lowering oil flow resistance and processing costs. Simultaneously, it reduces the risk of leakage caused by complex structures, improving the system's sealing and reliability. The return oil hole and closed-loop oil circuit design ensure uniform lubrication and cooling effect, extending oil life and reducing maintenance costs. When modifying ECVT models, this oil circuit layout only requires minor adjustments to some structures, such as the depth of the oil intake hole or the position of the return oil hole, to adapt to new lubrication requirements without redesigning the entire oil circuit, greatly reducing the workload and improving the system's flexibility and adaptability. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the oil circuit of this utility model.

[0017] Figure 2 This is a schematic diagram of the oil circuit of this utility model.

[0018] Figure 3 This is a schematic diagram of the oil collection hole of this utility model.

[0019] Figure 4 This is a schematic diagram of the oil return hole of this utility model.

[0020] Reference numerals in the attached diagram: 1: Main oil passage; 2: Oil intake hole; 3: Oil intake section; 4: Left housing; 5: Right housing; 6: First oil passage hole; 7: Second oil passage hole; 8: Steering cavity; 9: Connecting cavity; 10: Oil outlet; 11: Gear shaft; 12: Gear; 13: Return oil hole; 14: Oil collection hole. Detailed Implementation

[0021] In electronically controlled continuously variable transmission (ECVT) systems, the rationality of the oil circuit layout directly affects lubrication efficiency, system reliability, and flexibility in model upgrades. The electronically controlled CVT oil circuit layout provided by this invention, through the precise coordination of the left housing 4 and the right housing 5, constructs a simple and efficient lubrication path, effectively solving the problems of complex traditional oil circuit structures and significant modifications required for model upgrades.

[0022] like Figure 1 and Figure 2 As shown, the oil circuit arrangement is based on the left housing 4 and the right housing 5 as the basic load-bearing structure. The main oil passage 1 on the right housing 5 is the source channel of the oil. The main oil passage 1 is equipped with an oil intake hole 2, which is responsible for drawing oil from the main oil passage 1 into the lubrication branch. The right housing 5 is machined with a first oil passage hole 6 with one end open, and the left housing 4 is equipped with a second oil passage hole 7 with one end open at the corresponding position. When the left and right housings 5 ​​are spliced, the first oil passage hole 6 and the second oil passage hole 7 are precisely aligned to form a complete oil intake channel, forming the core path for the oil to flow from the main oil passage 1 to the lubrication point. The oil intake hole 2 is directly connected to the first oil passage hole 6. After the oil enters the first oil passage hole 6 through the oil intake hole 2, it continues to flow through the oil intake channel formed by the splicing of the left and right housings 5. The second oil passage hole 7 is connected to the oil collection hole 14 on the gear shaft 11 through the connecting cavity 9, and finally delivers the oil to the gear shaft 11 for lubrication. The right housing 5 has several oil return holes 13 located below the gear 12. These holes guide the lubricated oil back to the oil tank, completing the oil circulation. The oil forms a short circulation within the tank, effectively reducing oil temperature and extending oil life through natural or auxiliary cooling. The closed-loop oil circuit automatically adjusts the oil flow according to operating conditions, eliminating the need for external adjustment devices and improving system adaptability. This reduces lubrication failures caused by insufficient oil.

[0023] like Figure 1As shown, the vertical arrangement of oil intake hole 2 and oil intake section 3 is a key design feature for optimizing oil flow. The vertical connection between oil intake hole 2 and oil intake section 3 minimizes the number of bends in the oil path, eliminating the need for frequent changes in oil direction during flow, significantly reducing flow resistance and improving flow efficiency. From a manufacturing perspective, the vertical structure is easier to machine, facilitating precise forming through machining, reducing machining errors, and improving production efficiency. Simultaneously, the simplified oil path reduces the risk of leakage due to structural complexity, decreasing the number of oil path interfaces and sealing points, thus significantly improving overall system reliability. More importantly, during ECVT upgrades, this design only requires adjusting the depth of oil intake hole 2 to change the oil intake volume, eliminating the need to redesign the entire oil path's routing and structure, greatly reducing the workload and cost of upgrades.

[0024] The connection method between the oil intake section 3 and the first oil passage hole 6 further optimizes the structural compactness and sealing performance. The oil intake section 3 is perpendicularly connected to the first oil passage hole 6, and the oil intake section 3 extends beyond the end of the first oil passage hole 6. This design reduces the use of additional seals, thereby reducing costs and avoiding the risk of leakage due to seal aging. At the same time, the reduction in the use of connecting parts makes the overall oil circuit structure simpler. When the system needs maintenance or repair, operators can quickly identify the oil circuit path, facilitating troubleshooting and improving maintenance efficiency.

[0025] like Figure 1 and Figure 2 As shown, the design of the steering cavity 8 at the end of the second oil passage 7 embodies a combination of ease of machining and functional optimization. The steering cavity 8 adopts a rectangular structure. The advantage of a rectangular cavity is that it can be directly formed through CNC machining or casting, eliminating the need for additional fitter finishing steps required for arc-shaped cavities, significantly simplifying the machining process and reducing production costs. The relatively large volume of the rectangular cavity allows it to act as a "buffer chamber" when the system experiences alternating hot and cold operating conditions. When the oil temperature rises, causing oil expansion or oil pressure fluctuations, the cavity can accommodate excess oil or absorb pressure peaks, effectively suppressing oil pressure pulses and reducing system noise, vibration, and acoustic harshness (NVH). The reduction in oil pressure pulses directly reduces system failures caused by pressure fluctuations, such as seal damage and loose oil circuit interfaces, improving the overall reliability of the system.

[0026] like Figure 2As shown, the steering cavity 8 is connected to the connecting cavity 9, which is inclined towards the gear shaft 11. This inclined design fully utilizes the principles of physics and mechanics. During oil flow, the inclined angle causes the oil to accelerate towards the gear shaft 11 under the combined action of gravity and the centrifugal force generated by the rotation of the gear shaft 11. Especially under high-speed conditions, the centrifugal force is more significant, resulting in faster oil flow and greatly improving lubrication efficiency. At the same time, the inclined design reduces the detours and turns of the oil passage, making the connection between the connecting cavity 9 and the gear shaft 11 more direct, resulting in a more compact overall structure and saving internal space in the housing. The shortened oil flow path also reduces the lag in oil flow. When operating conditions change rapidly (such as sudden acceleration), the lubrication system can respond quickly and provide sufficient oil to the gear shaft 11 in a timely manner to adapt to dynamic operating conditions.

[0027] like Figure 2 and Figure 3 As shown, an oil outlet 10 is provided at the end of the connecting cavity 9 near the gear shaft 11. The oil outlet 10 is precisely aligned with the oil collection hole 14 on the gear shaft 11, and the two are designed to be concentric. This concentric design ensures that the oil sprayed from the oil outlet 10 enters the oil collection hole 14 in a basically straight line, avoiding the oil churning loss caused by the collision between the oil and the edge of the oil collection hole 14 during side spraying. Traditional side spraying causes some oil to splash into non-target areas, which not only wastes oil but also increases energy loss due to the additional friction between the oil and the parts. The concentric design ensures that all the oil enters the oil collection hole 14, improving lubrication efficiency and reducing energy loss. The energy-saving effect is even more obvious under high-speed conditions.

[0028] The rectangular design of the steering cavity 8 offers advantages in both machining and functionality. The rectangular cavity can be directly formed through CNC machining or casting, eliminating the need for manual finishing compared to an arc-shaped cavity, thus reducing machining costs and time. Functionally, the larger cavity volume can accommodate changes in oil volume under alternating hot and cold conditions. When the oil temperature rises and the oil expands, the cavity provides a buffer space; when the oil temperature drops and the oil contracts, the cavity stabilizes the oil pressure, effectively suppressing oil pressure pulsations. This reduction in oil pressure pulsations not only lowers system noise and vibration but also reduces failures such as seal fatigue and oil circuit blockage caused by pressure fluctuations, significantly improving the overall reliability of the system.

[0029] The synergistic action of each component creates a highly efficient lubrication system: oil from the main oil passage 1 enters the first oil passage hole 6 through the oil inlet 2, and is sealed by the vertical extension structure of the oil inlet section 3. After flowing through the oil inlet connected by the left and right housings 5, the oil enters the rectangular steering cavity 8 of the second oil passage hole 7. After the steering cavity 8 buffers the oil pressure pulse, the oil is accelerated to the outlet 10 through the inclined connecting cavity 9, and finally enters the gear shaft 11 through the concentrically designed outlet 10 and the oil collection hole 14 to complete lubrication. The lubricated oil flows back through the return hole 13. This structural design allows for adaptation to new operating conditions when modifying the ECVT, requiring only adjustment of the depth of the oil inlet 2 without redesigning the overall oil circuit layout, significantly reducing the workload. At the same time, the compact structure and optimized sealing and flow design reduce leakage risk and energy loss, improve system reliability and lubrication efficiency, and provide a strong guarantee for the stable operation of the ECVT.

[0030] like Figure 2 As shown, several return oil holes 13 are tightly connected to and interconnected with the bottom of the tank, and then connected to the main oil passage via an oil pump, thus constructing a complete closed-loop oil circuit system. In this embodiment, after careful design and repeated consideration, two return oil holes 13 are preferably set. When the oil circulates in the system, it smoothly returns to the bottom of the tank through these two return oil holes 13. Subsequently, the oil pump will promptly and efficiently draw the oil back from the bottom of the tank and deliver it back to the main oil passage, thus repeating the cycle to ensure that the oil circuit is always in a stable and continuous closed-loop state. This design not only ensures the smooth flow of oil in the system, but also effectively avoids leakage or waste of oil during circulation, improving the operating efficiency and reliability of the entire system. At the same time, the setting of two return oil holes 13 also provides a certain degree of redundancy to the system. Even if one return oil hole fails, the other can still continue to maintain the basic circulation of the oil circuit, further enhancing the stability and safety of the system.

[0031] The closed-loop oil circuit formed by the oil return hole 13 and the main oil passage 1 is the core guarantee for the efficient operation of the system. The closed-loop design allows the oil to form a complete circulation path within the tank: the oil is transported from the main oil passage 1 to the lubrication point through the oil intake passage, and after lubrication, it flows back to the main oil passage 1 through the oil return hole 13, realizing a short cycle of "oil intake - lubrication - oil return". This circulation mode allows the oil to be cooled quickly through the tank's natural cooling or auxiliary cooling device, effectively reducing the oil temperature, preventing the oil from aging and deteriorating due to long-term high temperature, and significantly extending the oil's life.

[0032] The closed-loop oil circuit design reduces the use of external pipelines, which not only lowers pipeline maintenance costs but also avoids the risk of leakage caused by aging of external pipelines and loose joints, improves the overall reliability of the system, and reduces lubrication failures caused by insufficient oil.

[0033] The vertical arrangement of the connecting cavity 9 and the oil intake channel further optimizes the machining process and operational stability of the oil circuit. The vertically intersecting oil channel layout reduces the need for multiple drilling layers inside the housing. Traditional oblique or circuitous oil circuits often require multiple drilling layers to avoid other structures, making machining difficult and prone to drilling deviations; while the vertical arrangement only requires drilling in two directions to form a passage, reducing machining difficulty and cost. The intersection of the oil channels naturally forms a throttling structure. When the oil flows through the vertical intersection, the flow velocity stabilizes briefly, reducing oil pressure instability caused by flow fluctuations and improving lubrication stability. Furthermore, the vertical arrangement reduces the detours and bends in the oil circuit, making the internal space layout of the housing more compact, optimizing space utilization, and reserving ample space for the arrangement of other components.

[0034] The oil inlet 14 is located on one side of the gear shaft 11. This single-sided oil inlet design provides an efficient path for bearing lubrication. When the oil flows from the single-sided outlet 10 to the oil inlet 14, a wedge-shaped oil film is formed between the bearing and the journal. This wedge-shaped oil film has a stronger load-bearing capacity, effectively disperses the pressure on the bearing, reduces wear, and extends the bearing's service life. The single-sided oil inlet allows the oil to flow directly to the lubrication point without having to travel around the circumference of the gear shaft 11, shortening the flow path. When operating conditions change rapidly (such as sudden acceleration), the oil can reach the lubrication point faster, significantly improving the lubrication response speed and avoiding brief dry friction caused by lubrication lag.

[0035] The synergistic effect of each component comprehensively enhances the performance of the entire hydraulic system. The closed-loop hydraulic circuit achieves efficient oil circulation, reducing oil temperature and extending lifespan; vertical oil passages simplify machining and stabilize oil pressure; and the single-sided oil port 14 accelerates lubrication response and enhances bearing capacity. These design features together constitute a simple and reliable hydraulic system.

[0036] The advantages of this oil circuit layout are particularly evident when redesigning the ECVT: adjusting the depth of the oil intake hole 2 changes the oil intake volume without requiring a complete redesign of the oil circuit, significantly reducing the workload. The simplified oil circuit structure reduces oil passage bends and the number of parts, lowering oil flow resistance and manufacturing costs. It also reduces sealing points, lowering the risk of leakage and improving system sealing. The circumferentially uniform return oil hole 13 and the closed-loop oil circuit ensure uniform lubrication and cooling, reducing maintenance costs.

[0037] In summary, this electronically controlled continuously variable transmission (ECVT) oil circuit layout, through simplified and optimized structural design, improves lubrication efficiency and system reliability while also taking into account the flexibility of model upgrades and cost control, providing strong support for the stable operation and rapid iteration of the ECVT system.

Claims

1. An electronically controlled continuously variable transmission (CVT) hydraulic circuit layout, characterized in that, It includes a left box and a right box. The main oil passage on the right box is provided with an oil intake hole. The right box is provided with a first oil passage hole with one end open. The left box is provided with a second oil passage hole with one end open. The first oil passage hole and the second oil passage hole are joined together to form an oil intake passage. The oil intake hole is connected to the first oil passage hole, and the second oil passage hole is connected to the oil collection hole on the gear shaft through the connecting cavity. Several oil return holes are provided on the right housing below the gear.

2. The electronically controlled continuously variable transmission (CVT) oil circuit arrangement according to claim 1, characterized in that, The oil sampling hole and the oil sampling section are connected and are set vertically.

3. The electronically controlled continuously variable transmission (CVT) oil circuit arrangement according to claim 2, characterized in that, The oil intake section is connected to one end of the first oil passage hole, and the oil intake section is perpendicular to the first oil passage hole and extends out of the end of the first oil passage hole.

4. The electronically controlled continuously variable transmission (CVT) oil circuit arrangement according to claim 3, characterized in that, The end of the second oil passage is provided with a steering cavity, which is rectangular.

5. The electronically controlled continuously variable transmission (CVT) oil circuit arrangement according to claim 4, characterized in that, The steering cavity is connected to the connecting cavity, which is inclined toward the gear shaft.

6. The electronically controlled continuously variable transmission (CVT) oil circuit arrangement according to claim 1 or 5, characterized in that, An oil outlet is provided at the end of the connecting cavity near the gear shaft, and the oil outlet faces the oil collection hole.

7. An electronic controlled infinitely variable hydraulic circuit arrangement according to claim 1, characterized in that, Several return oil holes are connected to the main oil passage to achieve a closed-loop oil circuit.

8. An electronic controlled infinitely variable oil circuit arrangement according to claim 1 or 7, characterized in that Several return oil holes are connected to the bottom of the tank, and the main oil passage is connected through an oil pump to achieve a closed-loop oil circuit.

9. An electronic controlled infinitely variable hydraulic circuit arrangement according to claim 6, characterized in that The connecting cavity is set perpendicular to the oil intake channel.

10. The electronically controlled continuously variable transmission (CVT) oil circuit arrangement according to claim 6, characterized in that, The oil port is located on one side of the gear shaft.

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