Gearbox lubrication system, method and vehicle

Abstract

This application relates to a transmission lubrication system, method, and automobile, comprising: a main gearbox with a main gearbox oil sump inside, the main gearbox having a spray lubrication mechanism and an oil churning lubrication mechanism; and an auxiliary gearbox with an auxiliary gearbox oil sump inside, the auxiliary gearbox being isolated from the main gearbox by a partition, the partition having a thermostat installed on it; when the temperature is lower than a set temperature, the thermostat opens and connects the main gearbox oil sump and the auxiliary gearbox oil sump; when the temperature is higher than the set temperature, the thermostat closes and isolates the main gearbox oil sump and the auxiliary gearbox oil sump. During a cold start at low temperatures, the thermostat is opened, and the transmission primarily uses oil churning lubrication to ensure reliable operation; when the transmission is at normal operating temperature, the thermostat is closed, and the main gearbox gears primarily use spray lubrication, thus ensuring sufficient lubrication for both the main and auxiliary gearboxes at different temperatures. Furthermore, when the transmission is at normal operating temperature, the fluid levels in the main and auxiliary gearboxes are not equal, reducing oil churning losses in the main gearbox and thereby improving the transmission efficiency.

Description

Technical Field

[0001] This invention relates to the field of transmission and speed change systems, and more specifically to a gearbox lubrication system, method, and automobile. Background Technology

[0002] Currently, gearboxes utilize the meshing of different gears. The contact between gears generates friction, which leads to wear over time. Using lubricating oil can protect the gears, reduce wear on the gear surfaces, improve the fatigue resistance of the gear surfaces, prevent scuffing damage, and reduce vibration and noise in gear transmissions.

[0003] In related technologies, gearbox lubrication solutions generally adopt a two-shaft central oil pipe active lubrication + churning lubrication method. The oil pump draws oil from the oil sump, and the lubricating oil enters the active lubrication system. The oil volume is distributed through the two-shaft central oil pipe to lubricate the shaft teeth and other parts. The heat generated by gear meshing needs to be carried away by the lubricating oil.

[0004] However, this method requires a large amount of oil to meet the needs of the lubrication system, and the resulting oil churning loss is significant, which is not conducive to improving the efficiency of the transmission. Summary of the Invention

[0005] This application provides a transmission lubrication system, method, and automobile. During a cold start at low temperatures, the thermostat is activated, allowing the main and auxiliary transmission lubricating oils to communicate. The transmission primarily uses churning lubrication to ensure reliable operation. At high temperatures, the thermostat is deactivated, separating the main and auxiliary transmission lubricating oils. The main transmission gears primarily use spray lubrication, ensuring sufficient lubrication at different temperatures. Furthermore, when the transmission is at normal operating temperature, the fluid levels in the main and auxiliary transmissions are not equal, reducing churning losses in the main transmission and improving transmission efficiency. This addresses the problem in related technologies where a large amount of oil is required to meet the lubrication system's needs, resulting in significant churning losses that hinder transmission efficiency.

[0006] In a first aspect, embodiments of this application provide a gearbox lubrication system, comprising: a main gearbox having a main gearbox oil sump inside, the main gearbox having a spray lubrication mechanism and an oil stirring lubrication mechanism; and an auxiliary gearbox having an auxiliary gearbox oil sump inside, the auxiliary gearbox being isolated from the main gearbox by a partition, the partition being equipped with a thermostat; when the temperature is lower than a set temperature, the thermostat opens and connects the main gearbox oil sump and the auxiliary gearbox oil sump; when the temperature is higher than the set temperature, the thermostat closes and blocks the main gearbox oil sump and the auxiliary gearbox oil sump. By installing a thermostat between the main and auxiliary gearboxes, and incorporating a spray lubrication mechanism and an oil-stirring lubrication mechanism within the main gearbox, the spray lubrication mechanism provides lubrication to the transmission, suitable for situations with low oil levels. The oil-stirring lubrication mechanism provides lubrication by stirring the oil, suitable for situations with high oil levels. During a cold start at low temperatures, the thermostat is activated, allowing the main and auxiliary gearboxes to communicate and maintain equal fluid levels. The transmission primarily uses oil-stirring lubrication to ensure reliable operation. At normal operating temperature, the thermostat is deactivated, separating the main and auxiliary gearboxes. The fluid level in the main gearbox is lower than that in the auxiliary gearbox, and the main gearbox gears primarily use spray lubrication. This ensures adequate lubrication for both gearboxes at different temperatures. Furthermore, the unequal fluid levels in the main and auxiliary gearboxes at normal operating temperature reduce oil-stirring losses in the main gearbox, thereby improving transmission efficiency.

[0007] The opening temperature range of the thermostat can be adjusted according to the design requirements of the transmission. The viscosity of the lubricating oil used in the transmission is different at different temperatures. When the temperature reaches T, the viscosity of the lubricating oil decreases, and the oil pressure of the active lubrication system reaches the design acceptable range. This temperature T can be used as the opening temperature of the thermostat. When the temperature is lower than the set temperature, the thermostat is open, the main and auxiliary gearboxes are connected, and there will be no uneven oil levels between the main and auxiliary gearboxes. The main gearbox gears are mainly lubricated by churning. When the temperature is higher than the set temperature, the thermostat is closed, and uneven liquid levels are formed between the main and auxiliary gearboxes.

[0008] In conjunction with the first aspect, in one embodiment, the gearbox includes an intermediate shaft, and the height of the thermostat is lower than the height of the intermediate shaft. By placing the thermostat below the intermediate shaft, preferably at the lower end of the oil chamber, the main gearbox oil sump and the auxiliary gearbox oil sump are not connected below the intermediate shaft. However, since the thermostat is located at the lower end of the oil chamber, the auxiliary gearbox can be used as an oil reservoir. An oil passage connects the auxiliary gearbox to the thermostat. During cold starts at low temperatures, the thermostat is activated, allowing the main and auxiliary gearbox lubricating oils to communicate, and the gearbox primarily uses churning lubrication to ensure reliable operation. During high temperatures, the thermostat is deactivated, the main and auxiliary gearbox lubricating oils are not connected, and the main gearbox gears primarily use spray lubrication, reducing churning losses and improving lubrication efficiency.

[0009] In conjunction with the first aspect, in one embodiment, the partition plate is provided with an oil return hole, the height of which is higher than the height of the intermediate shaft. By adding an oil return hole in the middle of the main and auxiliary gearbox partition, when the oil level in the auxiliary gearbox reaches or exceeds the height of the meshing part between the planetary gear and the gear ring, the oil return hole provided on the main and auxiliary gearbox partition becomes active. Excess oil flows to the auxiliary gearbox through the oil return hole, which can prevent the auxiliary gearbox from becoming full of oil, causing the planetary gear system to churn and increasing oil churning losses.

[0010] The lubricating oil from the auxiliary gearbox flows to the main gearbox through the following main pathways: Pathway 1: When the thermostat is open at low temperatures, the lubricating oil from the auxiliary gearbox can flow to the main gearbox. Pathway 2: An opening in the center of the intermediate shaft cover allows the oil flowing to the main gearbox through the bearing clearance of the intermediate shaft during normal gearbox operation to flow at a speed less than the speed of the oil entering the auxiliary gearbox through the central oil pipe of the second shaft. This creates a dynamic oil level with a lower level in the main gearbox and a higher level in the auxiliary gearbox, using the auxiliary gearbox as an oil reservoir and reducing oil churning losses in the main gearbox. Pathway 3: When the speed is very high, the amount of oil entering the auxiliary gearbox is much greater than the amount flowing to the main gearbox through the bearing clearance. When the fluid level in the auxiliary gearbox reaches or exceeds the height of the meshing part between the planetary gear and the ring gear, the return oil hole set on the main and auxiliary gearbox partition comes into play, and the excess oil flows to the auxiliary gearbox through this hole.

[0011] In conjunction with the first aspect, in one embodiment, the gearbox includes meshing planetary gears and a ring gear, and the height of the oil return hole is equal to the height of the meshing portion of the planetary gears and the ring gear. By adding an oil return hole in the middle of the main and auxiliary gearbox partition, and ensuring that the height of the oil return hole is equal to the height of the meshing portion of the planetary gears and the ring gear, the oil return hole on the main and auxiliary gearbox partition activates when the fluid level in the auxiliary gearbox reaches or exceeds the height of the meshing portion of the planetary gears and the ring gear. Excess oil flows to the auxiliary gearbox through the oil return hole, preventing the auxiliary gearbox from becoming completely filled with oil, which would cause churning of the planetary gears and increase oil churning losses.

[0012] Secondly, embodiments of this application provide a lubrication method for a transmission lubrication system, comprising the following steps: acquiring transmission temperature data; when the temperature is lower than a set temperature, controlling the thermostat to open and connecting the main transmission oil sump and the auxiliary transmission oil sump, and using an oil stirring lubrication mechanism for lubrication; when the temperature is higher than the set temperature, the thermostat to close and isolate the main transmission oil sump and the auxiliary transmission oil sump, and using a spray lubrication mechanism for lubrication.

[0013] In conjunction with the second aspect, in one embodiment, the lubrication method further includes: when the liquid level in the auxiliary tank exceeds the height of the meshing part of the planetary gear and the ring gear, using the oil return hole to allow the oil in the auxiliary tank to flow back to the main tank.

[0014] In conjunction with the second aspect, in one embodiment, the lubrication method further includes: driving a portion of the oil from the central oil pipe of the two shafts into and lubricating the planetary gear train of the auxiliary gearbox.

[0015] In conjunction with the second aspect, in one embodiment, the lubrication method further includes: drilling a hole in the sun gear to drive oil flow into and lubricate the planetary gear system.

[0016] In conjunction with the second aspect, in one embodiment, the lubrication method further includes: utilizing the clearance of the intermediate shaft rear bearing to flow to the main housing at a speed less than the speed of the oil pipe of the second shaft entering the auxiliary housing, so that the oil level in the main housing is lower than the oil level in the auxiliary housing.

[0017] Thirdly, this application provides an automobile comprising the aforementioned transmission lubrication system. The transmission lubrication system includes: a main gearbox containing a main gearbox oil sump, and a spray lubrication mechanism and an oil-stirring lubrication mechanism; and an auxiliary gearbox containing an auxiliary gearbox oil sump, the auxiliary gearbox being separated from the main gearbox by a partition, on which a thermostat is mounted. When the temperature is lower than a set temperature, the thermostat opens and connects the main gearbox oil sump and the auxiliary gearbox oil sump; when the temperature is higher than the set temperature, the thermostat closes and blocks the main gearbox oil sump and the auxiliary gearbox oil sump. An intermediate shaft is provided within the transmission, and the height of the thermostat is lower than the height of the intermediate shaft. An oil return hole is provided on the partition, and the height of the oil return hole is higher than the height of the intermediate shaft. Meshing planetary gears and a ring gear are provided within the transmission, and the height of the oil return hole is equal to the height of the meshing portion of the planetary gears and the ring gear.

[0018] The beneficial effects of the technical solutions provided in this application include:

[0019] This invention provides a transmission lubrication system, method, and automobile. During a cold start at low temperatures, the thermostat is activated, allowing the main and auxiliary transmission lubricating oils to communicate. The transmission primarily uses churning lubrication to ensure reliable operation. At normal operating temperature, the thermostat is deactivated, and the main and auxiliary transmission lubricating oils are no longer connected. The main transmission gears primarily use spray lubrication, ensuring sufficient lubrication at different temperatures. Furthermore, at normal operating temperature, the fluid levels in the main and auxiliary transmissions are not equal, reducing churning losses in the main transmission and thus improving transmission efficiency. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of a gearbox lubrication system provided in an embodiment of the present invention;

[0022] Figure 2 A cross-sectional view of a gearbox lubrication system provided in an embodiment of the present invention;

[0023] Figure 3 This is a diagram showing the arrangement of the oil return hole and the temperature controller provided in an embodiment of the present invention.

[0024] Figure 4 This is a schematic diagram of the spray lubrication mechanism provided in an embodiment of the present invention.

[0025] Numbering on the map:

[0026] 1. Main gearbox; 2. Spray lubrication mechanism; 3. Auxiliary gearbox; 4. Oil stirring lubrication mechanism; 5. Partition plate; 6. Temperature regulator; 7. Intermediate shaft; 8. Central oil pipe of the two shafts; 9. Meshing height of the gear ring and planetary gears; 10. Through hole of the intermediate shaft cover plate; 11. Intermediate shaft cover plate; 12. Oil return hole; 13. Spray gear; 14. Pump; 15. Oil suction device; 16. Filtering and cooling device; 17. Planetary lubrication system. Detailed Implementation

[0027] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0028] This application provides a transmission lubrication system, method, and automobile that can solve the problem in related technologies where a large amount of oil is needed to meet the lubrication system's requirements, and the resulting oil churning loss is significant, which is detrimental to improving transmission efficiency.

[0029] Figure 1 and Figure 2 This invention provides a gearbox lubrication system comprising: a main gearbox 1, which has a main gearbox oil sump inside, and a spray lubrication mechanism 2 and an oil stirring lubrication mechanism 4 inside the main gearbox 1; and an auxiliary gearbox 3, which has an auxiliary gearbox oil sump inside, the auxiliary gearbox 3 being isolated from the main gearbox 1 by a partition 5, and a thermostat 6 being installed on the partition 5; when the temperature is lower than a set temperature, the thermostat 6 opens and connects the main gearbox oil sump and the auxiliary gearbox oil sump; when the temperature is higher than the set temperature, the thermostat 6 closes and blocks the main gearbox oil sump and the auxiliary gearbox oil sump.

[0030] In this embodiment, a thermostat 6 is installed between the main gearbox 1 and the auxiliary gearbox 3, and a spray lubrication mechanism 2 and an oil-stirring lubrication mechanism 4 are installed in the main gearbox 1. The spray lubrication mechanism 2 is used to spray lubricate the gearbox, which is suitable for situations where the oil level in the tank is low. The oil-stirring lubrication mechanism 4 is used to stir lubricate the gearbox, which is suitable for situations where the oil level in the tank is high. When the vehicle is cold-started at low temperatures, the thermostat 6 is turned on, the lubricating oil in the main and auxiliary gearboxes is connected, and the fluid levels in the main gearbox 1 and the auxiliary gearbox 3 are equal. The gearbox mainly uses oil-stirring lubrication to ensure reliable operation of the gearbox. When the vehicle is at normal operating temperature, the thermostat 6 is turned off, the lubricating oil in the main and auxiliary gearboxes is not connected, the fluid level in the main gearbox 1 is lower than that in the auxiliary gearbox 3, and the gearbox gears mainly use spray lubrication. This ensures that the main and auxiliary gearboxes can be adequately lubricated at different temperatures. Furthermore, when the gearbox is at normal operating temperature, the fluid levels in the main and auxiliary gearboxes are not equal, reducing the oil-stirring loss in the main gearbox and thus improving the transmission efficiency of the gearbox.

[0031] The thermostat 6, also known as a thermostat, is a valve that controls the flow path of the coolant. As an automatic temperature control device, it typically contains a temperature-sensing component that opens or closes the flow of air, gas, or liquid through expansion or contraction. Its function is to automatically adjust the amount of water entering the radiator based on the engine's coolant temperature, changing the water circulation range to regulate the cooling system's heat dissipation capacity and ensure the engine operates within a suitable temperature range. The opening temperature range of the thermostat 6 can be adjusted according to the transmission design requirements. The viscosity of the lubricating oil used in the transmission varies at different temperatures. When the temperature reaches T, the viscosity of the lubricating oil decreases, and the oil pressure of the active lubrication system reaches the design acceptable range. This temperature T can be used as the opening temperature of the thermostat 6. When the temperature is lower than the set temperature, the thermostat 6 opens, connecting the main and auxiliary gearboxes and preventing unequal oil levels. The main gearbox gears are primarily lubricated by churning. When the temperature is higher than the set temperature, the thermostat 6 closes, resulting in unequal oil levels in the main and auxiliary gearboxes.

[0032] See Figure 1 and Figure 2 As shown, in some embodiments, the gearbox has an intermediate shaft 7, and the height of the thermostat 6 is lower than the height of the intermediate shaft 7. In this embodiment, by placing the thermostat 6 below the intermediate shaft 7, preferably at the lower end of the oil chamber, the main gearbox oil sump and the auxiliary gearbox oil sump are not connected below the intermediate shaft 7. However, since the thermostat 6 is placed at the lower end of the oil chamber, the auxiliary gearbox 3 can be used as an oil reservoir. It is connected to the thermostat 6 by an oil passage. When the vehicle is cold-started at low temperatures, the thermostat 6 is opened, and the lubricating oils of the main and auxiliary gearboxes are connected. The gearbox mainly uses oil churning lubrication to ensure reliable operation of the gearbox. When the temperature is high, the thermostat 6 is closed, and the lubricating oils of the main and auxiliary gearboxes are not connected. The gears of the main gearbox 1 mainly use spraying lubrication, reducing oil churning losses and improving lubrication efficiency.

[0033] See Figure 1 , Figure 2 and Figure 3As shown, in some embodiments, the partition 5 is provided with an oil return hole 12, the height of which is higher than the height of the intermediate shaft 7. In this embodiment, by adding an oil return hole 12 in the middle of the main and auxiliary gearbox partition, when the oil level in the auxiliary gearbox 3 reaches or exceeds the height of the meshing part between the planetary gear and the gear ring, the oil return hole 12 provided on the main and auxiliary gearbox partition will function, and excess oil will flow to the auxiliary gearbox 3 through the oil return hole 12, which can prevent the auxiliary gearbox 3 from being filled with oil, causing the planetary gear system to churn and increasing oil churning losses.

[0034] The flow of lubricating oil from the auxiliary gearbox 3 to the main gearbox 1 mainly includes the following pathways: Pathway 1: When the temperature regulator 6 is open at low temperatures, the lubricating oil from the auxiliary gearbox 3 can flow to the main gearbox 1. Pathway 2: The intermediate shaft cover plate 11 has an opening in the middle. When the gearbox is running normally, the speed at which the oil flows to the main gearbox 1 through the bearing clearance of the intermediate shaft is less than the speed at which the oil enters the auxiliary gearbox 3 through the central oil pipe 8 of the second shaft. This creates a dynamic oil level with a low level in the main gearbox 1 and a high level in the auxiliary gearbox 3, using the auxiliary gearbox 3 as an oil reservoir and reducing the oil churning loss in the main gearbox 1. Pathway 3: When the speed is very high, the amount of oil entering the auxiliary gearbox 3 is much greater than the amount of oil flowing to the main gearbox 1 through the bearing clearance. When the oil level in the auxiliary gearbox 3 reaches or exceeds the height of the meshing part between the planetary gear and the ring gear, the return oil hole 12 set on the main and auxiliary gearbox partition takes effect, and the excess oil flows to the auxiliary gearbox 3 through this hole.

[0035] See Figure 1 and Figure 2 As shown, in some embodiments, the gearbox contains meshing planetary gears and a ring gear, and the height of the oil return hole 12 is equal to the height of the meshing part of the planetary gears and the ring gear. In this embodiment, by setting the height of the oil return hole 12 at the height of the meshing part of the planetary gears and the ring gear, when the oil level in the auxiliary gearbox 3 reaches or exceeds the height of the meshing part of the planetary gears and the ring gear, the oil return hole 12 provided on the main and auxiliary gearbox partition will function. Excess oil will flow to the auxiliary gearbox 3 through the oil return hole 12, which can prevent the auxiliary gearbox 3 from becoming full of oil, causing the planetary gear system to churn and increasing oil churning losses.

[0036] See Figures 1-4As shown in the figure, this embodiment of the invention also provides a lubrication method for a gearbox lubrication system, which includes the following steps: acquiring the temperature data of the gearbox; when the temperature is lower than the set temperature, controlling the thermostat 6 to open and connect the main gearbox oil sump and the auxiliary gearbox oil sump, and using the oil stirring lubrication mechanism 4 for lubrication; when the temperature is higher than the set temperature, the thermostat 6 to close and block the main gearbox oil sump and the auxiliary gearbox oil sump, and using the spray lubrication mechanism 2 for lubrication. In this embodiment, a thermostat 6 is installed between the main gearbox 1 and the auxiliary gearbox 3, and a spray lubrication mechanism 2 and an oil-stirring lubrication mechanism 4 are installed in the main gearbox 1. The spray lubrication mechanism 2 is used to spray lubricate the gearbox, which is suitable for situations where the oil level in the tank is low. The oil-stirring lubrication mechanism 4 is used to stir lubricate the gearbox, which is suitable for situations where the oil level in the tank is high. When the vehicle is cold-started at low temperatures, the thermostat 6 is turned on, the lubricating oil in the main and auxiliary gearboxes is connected, and the fluid levels in the main gearbox 1 and the auxiliary gearbox 3 are equal. The gearbox mainly uses oil-stirring lubrication to ensure reliable operation of the gearbox. When the vehicle is at normal operating temperature, the thermostat 6 is turned off, the lubricating oil in the main and auxiliary gearboxes is not connected, the fluid level in the main gearbox 1 is lower than that in the auxiliary gearbox 3, and the gearbox gears mainly use spray lubrication. This ensures that the main and auxiliary gearboxes can be adequately lubricated at different temperatures. Furthermore, when the gearbox is at normal operating temperature, the fluid levels in the main and auxiliary gearboxes are not equal, reducing the oil-stirring loss in the main gearbox and thus improving the transmission efficiency of the gearbox.

[0037] See Figure 1 and Figure 2 As shown, in some embodiments, the lubrication method further includes: when the oil level in the auxiliary tank 3 exceeds the height of the meshing part of the planetary gear and the ring gear, the oil in the auxiliary tank 3 is returned to the main tank 1 using the oil return hole 12. In this embodiment, by adding an oil return hole 12 in the middle of the main and auxiliary tank partition, and the height of the oil return hole 12 is equal to the height of the meshing part of the planetary gear and the ring gear, when the oil level in the auxiliary tank 3 reaches or exceeds the height of the meshing part of the planetary gear and the ring gear, the oil return hole 12 provided on the main and auxiliary tank partition takes effect, and the excess oil flows to the auxiliary tank 3 through the oil return hole 12, which can prevent the auxiliary tank 3 from being filled with oil, causing the planetary gear to churn and increasing oil loss.

[0038] See Figure 1 and Figure 2 As shown, in some embodiments, the lubrication method further includes: driving a portion of the oil from the central oil pipe 8 of the two shafts to enter and lubricate the planetary gear train of the auxiliary gearbox 3. In this embodiment, the gearbox is lubricated through the oil filling hole in the middle housing, and drained through the drain holes of the main and auxiliary gearboxes. The roller gears on the two shafts of the gearbox are lubricated by oil pipes arranged inside the two shafts for oil distribution, and then by different capillary channels for corresponding lubrication. A portion of the oil from the central oil pipe 8 of the two shafts is directed to the planetary gear train of the auxiliary gearbox 3 through a set lubrication oil passage to lubricate the planetary gear train and serve as the source of oil flow in the auxiliary gearbox 3.

[0039] See Figure 1 and Figure 2 As shown, in some embodiments, the lubrication method may further include: drilling a hole in the sun gear to drive oil flow into and lubricate the planetary gear train. In this embodiment, the lubrication of the planetary gear train in the auxiliary gearbox relies on two aspects: firstly, drilling a hole in the sun gear allows oil to flow into the gear meshing area to form lubrication; secondly, the height of the oil return hole is set to the meshing height of the planetary gear and the ring gear, which precisely satisfies the oil churning lubrication requirement at this location. When the oil level in the auxiliary gearbox 3 exceeds this meshing height, the lubricating oil enters the main gearbox 1 through the oil return hole.

[0040] See Figure 1 and Figure 2 As shown, in some embodiments, the lubrication method further includes: utilizing the clearance of the intermediate shaft rear bearing to ensure that the speed of oil flowing to the main gearbox 1 is less than the speed of oil entering the auxiliary gearbox 3 through the central oil pipe 8 of the second shaft, thus creating a situation where the oil level in the main gearbox 1 is lower than the oil level in the auxiliary gearbox 3. In this embodiment, by opening a hole in the middle of the intermediate shaft cover plate 11, when the gearbox is operating normally, the speed of oil flowing to the main gearbox 1 through the clearance of the intermediate shaft rear bearing is less than the speed of oil entering the auxiliary gearbox 3 through the central oil pipe 8 of the second shaft. This creates a dynamic oil level where the main gearbox 1 is low and the auxiliary gearbox 3 is high, using the auxiliary gearbox 3 as an oil reservoir and reducing the oil churning loss in the main gearbox 1.

[0041] This invention also provides an automobile comprising the aforementioned transmission lubrication system. The transmission lubrication system includes: a main gearbox 1, which has a main gearbox oil sump inside, and a spray lubrication mechanism 2 and an oil stirring lubrication mechanism 4 are provided within the main gearbox 1; and an auxiliary gearbox 3, which has an auxiliary gearbox oil sump inside, the auxiliary gearbox 3 being isolated from the main gearbox 1 by a partition 5, on which a thermostat 6 is installed; when the temperature is lower than a set temperature, the thermostat 6 opens and connects the main gearbox oil sump and the auxiliary gearbox oil sump; when the temperature is higher than the set temperature, the thermostat 6 closes and blocks the main gearbox oil sump and the auxiliary gearbox oil sump. An intermediate shaft 7 is provided within the transmission, and the height of the thermostat 6 is lower than the height of the intermediate shaft 7. An oil return hole 12 is provided on the partition 5, and the height of the oil return hole 12 is higher than the height of the intermediate shaft 7. Meshing planetary gears and a ring gear are provided within the transmission, and the height of the oil return hole 12 is equal to the height of the meshing portion of the planetary gears and the ring gear.

[0042] In this embodiment, a thermostat 6 is installed between the main gearbox 1 and the auxiliary gearbox 3, and a spray lubrication mechanism 2 and an oil-stirring lubrication mechanism 4 are installed in the main gearbox 1. The spray lubrication mechanism 2 is used to spray lubricate the gearbox, which is suitable for situations where the oil level in the tank is low. The oil-stirring lubrication mechanism 4 is used to stir lubricate the gearbox, which is suitable for situations where the oil level in the tank is high. When the vehicle is cold-started at low temperatures, the thermostat 6 is turned on, the lubricating oil in the main and auxiliary gearboxes is connected, and the fluid levels in the main gearbox 1 and the auxiliary gearbox 3 are equal. The gearbox mainly uses oil-stirring lubrication to ensure reliable operation of the gearbox. When the vehicle is at normal operating temperature, the thermostat 6 is turned off, the lubricating oil in the main and auxiliary gearboxes is not connected, the fluid level in the main gearbox 1 is lower than that in the auxiliary gearbox 3, and the gearbox gears mainly use spray lubrication. This ensures that the main and auxiliary gearboxes can be adequately lubricated at different temperatures. Furthermore, when the gearbox is at normal operating temperature, the fluid levels in the main and auxiliary gearboxes are not equal, reducing the oil-stirring loss in the main gearbox and thus improving the transmission efficiency of the gearbox.

[0043] The technical solution has been tested on the project prototype. The preliminary solution has been verified to improve the efficiency of the gearbox by more than 0.6%, and it can be applied in future projects. Similar technologies can be extended to other product lines.

[0044] The principles of the transmission lubrication system, method, and automobile provided in this invention are as follows:

[0045] The gearbox lubrication system is mainly achieved through the main gearbox 1, auxiliary gearbox 3, thermostat 6, and spray lubrication mechanism 2. This lubrication system primarily uses active lubrication, supplemented by churning lubrication. Specifically, at low temperatures, the main and auxiliary gearboxes are connected, with a higher fluid level in the main gearbox 1, allowing the gears to churn the oil. At high temperatures, the fluid level in the main gearbox 1 decreases, and the oil is stored in the auxiliary gearbox 3. The gears in the main gearbox are lubricated by the spray mechanism. By employing a lubrication structure with unequal fluid levels in the main and auxiliary gearboxes, all gears in the main gearbox, except for the reverse gear, are lubricated by spray. The oil chambers of the main gearbox 1 and auxiliary gearbox 3 are not connected below the intermediate shaft 7, but a thermostat 6 is located at the bottom of the oil chamber. The bottom of the auxiliary gearbox serves as an oil reservoir, connected to the thermostat 6 via an oil passage. When the vehicle is cold-started at low temperatures, the thermostat 6 is open, and the lubricating oil in the main and auxiliary gearboxes is connected. The gearbox mainly uses oil churning for lubrication, ensuring reliable operation of the gearbox. When the temperature is high, the thermostat 6 is closed, and the lubricating oil in the main and auxiliary gearboxes is not connected. The main gearbox gears mainly use spraying, reducing oil churning losses and improving lubrication efficiency. An oil return hole 12 is added in the middle of the partition between the main and auxiliary gearboxes to prevent the auxiliary gearbox 3 from being filled with oil, which would cause planetary oil churning and increase oil churning losses.

[0046] The opening temperature range of the thermostat 6 can be adjusted according to the design requirements of the gearbox. The viscosity of the lubricating oil used in the gearbox is different at different temperatures. When the temperature reaches T, the viscosity of the lubricating oil decreases. At this time, the oil pressure value of the active lubrication system reaches the design acceptable range. This temperature T can be used as the opening temperature of the thermostat 6. When the temperature is lower than the set temperature, the thermostat 6 is opened, the main and auxiliary gearboxes are connected, and the oil levels of the main and auxiliary gearboxes will not be unequal. The main gearbox gears are mainly lubricated by churning. When the temperature is higher than the set temperature, the thermostat 6 is closed, and the oil levels of the main and auxiliary gearboxes are unequal.

[0047] The transmission is filled through the filling hole in the middle housing, and drained through the main and auxiliary gearbox drain holes. The roller gears on the two shafts are lubricated by oil pipes arranged inside the two shafts, and then lubricated through different capillary tubes. A portion of the oil from the central oil pipe 8 of the two shafts is directed to the planetary gear train of the auxiliary gearbox 3 through a set lubrication oil passage to lubricate the planetary gear train and serve as the source of oil flow in the auxiliary gearbox 3. The auxiliary gearbox oil sump and the main gearbox oil sump are separated by the rear end face partition 5 of the middle housing.

[0048] The lubricating oil from the auxiliary gearbox 3 flows to the main gearbox 1 through the following main pathways: Pathway 1: When the temperature regulator 6 is open at low temperatures, the lubricating oil from the auxiliary gearbox 3 can flow to the main gearbox 1. Pathway 2: The intermediate shaft cover plate 11 has an opening in the middle. When the gearbox is running normally, the speed at which the oil flows to the main gearbox 1 through the bearing clearance of the intermediate shaft is less than the speed at which the oil enters the auxiliary gearbox 3 through the central oil pipe 8 of the second shaft. This creates a dynamic oil level with a low level in the main gearbox 1 and a high level in the auxiliary gearbox 3, using the auxiliary gearbox 3 as an oil reservoir and reducing the oil churning loss in the main gearbox 1. Pathway 3: When the speed is very high, the amount of oil entering the auxiliary gearbox 3 is much greater than the amount of oil flowing to the main gearbox 1 through the bearing clearance. When the oil level in the auxiliary gearbox 3 reaches or exceeds the height of the meshing part between the planetary gear and the ring gear, the return oil hole 12 set on the main and auxiliary gearbox partition takes effect, and the excess oil flows to the auxiliary gearbox 3 through this hole.

[0049] The lubrication of the planetary gear system in the auxiliary gearbox relies on two aspects: firstly, the sun gear is drilled to allow oil to flow into the gear meshing area to form lubrication; secondly, the height of the return oil hole is set to the meshing height of the planetary gear and the ring gear, which just meets the requirements for oil stirring and lubrication in this area. When the oil level in the auxiliary gearbox 3 exceeds this meshing height, the lubricating oil enters the main gearbox 1 through the return oil hole 12.

[0050] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0051] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0052] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A gearbox lubrication system characterized in that, It includes: The main box (1) is equipped with a main box oil sump inside. The main box (1) is equipped with a spray lubrication mechanism (2) and an oil stirring lubrication mechanism (4). The auxiliary tank (3) is equipped with an auxiliary tank oil sump inside. The auxiliary tank (3) is separated from the main tank (1) by a partition (5). A thermostat (6) is installed on the partition (5). When the temperature is lower than the set temperature, the thermostat (6) opens and connects the main tank oil sump and the auxiliary tank oil sump. The liquid levels of the main tank (1) and the auxiliary tank (3) are equal, and lubrication is achieved by the oil stirring lubrication mechanism (4). When the temperature is higher than the set temperature, the thermostat (6) closes and blocks the main tank oil sump and the auxiliary tank oil sump. The liquid level in the main tank (1) is lower than the liquid level in the auxiliary tank (3), and the spray lubrication mechanism (2) is used for lubrication. The gearbox is provided with an intermediate shaft (7), and the temperature regulator (6) is lower than the height of the intermediate shaft (7) and is located at the lower end of the oil chamber; The partition (5) is provided with an oil return hole (12), and the height of the oil return hole (12) is higher than the height of the intermediate shaft (7); The gearbox is equipped with intermeshing planetary gears and a gear ring, and the height of the oil return hole (12) is equal to the height of the meshing part of the planetary gears and the gear ring.

2. A method of lubricating a gearbox lubrication system as claimed in claim 1, characterized in that, It includes the following steps: Obtain the temperature data of the transmission; When the temperature is lower than the set temperature, the temperature controller (6) is opened and connected to the main tank oil sump and the auxiliary tank oil sump, and the oil stirring lubrication mechanism (4) is used for lubrication. When the temperature is higher than the set temperature, the thermostat (6) closes and blocks the main tank oil sump and the auxiliary tank oil sump, and lubricates by spraying lubrication mechanism (2).

3. The lubricating method of claim 2 wherein, The lubrication method further includes: When the liquid level in the auxiliary tank (3) exceeds the height of the meshing part of the planetary gear and the gear ring, the oil in the auxiliary tank (3) is returned to the main tank (1) by using the return oil hole (12).

4. The lubricating method of claim 2 wherein, The lubrication method further includes: Part of the oil from the central oil pipe (8) of the drive shaft enters and lubricates the planetary gear system of the auxiliary gearbox (3).

5. The lubricating method of claim 4 wherein, The lubrication method further includes: A hole is drilled in the sun gear to drive the flow of oil into and lubricate the planetary gear system.

6. The lubricating method of claim 2 wherein, The lubrication method further includes: The oil flow velocity to the main tank (1) is less than the velocity of the oil pipe (8) entering the auxiliary tank (3) from the intermediate shaft rear bearing clearance, resulting in the oil level in the main tank (1) being lower than the oil level in the auxiliary tank (3).

7. An automobile characterized by comprising: It includes the gearbox lubrication system as described in claim 1.

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