A lubrication structure and gearbox for controlling gearbox oil level height to improve transmission efficiency

Abstract

The present invention discloses a lubrication structure and a gearbox for controlling the oil level of a gearbox to improve transmission efficiency, comprising a gearbox housing, an intermediate shaft assembly, a spray lubrication unit and an oil pump arranged in the gearbox housing, a gear arranged on the intermediate shaft assembly, an oil baffle plate arranged between the gear and the bottom of the gearbox housing, the oil baffle plate enveloping the outer side of the gear, a first edge of the oil baffle plate being sealed and fixedly connected to a first inner wall of the gearbox housing, a gap being arranged between a second edge of the oil baffle plate and a second inner wall of the gearbox housing, a height of the second edge being equal to a tooth root circle of a gear with the smallest diameter among all gears, a terminal end of the intermediate shaft assembly being connected to an oil pump, and the oil pump providing lubricating oil for spray lubrication. The present invention is not only simple in structure, but also ensures the reliability of the gearbox operation, and minimizes the gear oil stirring loss, thereby improving the transmission efficiency of the gearbox.

Description

Technical Field

[0001] The invention discloses a lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency, belongs to the technical field of gearbox lubrication, and specifically discloses a lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency and a gearbox. Background Art

[0002] Power and economy are important indicators for evaluating the quality of heavy-duty commercial vehicles. For the gearbox assembly, the transmission efficiency index is often used to evaluate the economic performance of the gearbox. Data show that for high-speed logistics conditions, the average transmission efficiency of a heavy-duty gearbox is improved by 0.3%, and the economic performance of the vehicle is improved by 1.2%. The transmission efficiency of the gearbox is mainly affected by factors such as gear meshing loss, gear oil stirring loss, bearing loss, and oil pump power loss. Among them, gear oil stirring loss accounts for about 3% of the transmission power loss. The higher the oil level of the gearbox assembly, the deeper the gear oil immersion depth, the greater the gear oil stirring loss, and the lower the transmission efficiency.

[0003] Traditional gearbox lubrication systems generally use splash lubrication or splash lubrication + active lubrication. Splash lubrication is mainly oil immersion lubrication, and active lubrication mainly relies on the oil pump to pump the lubricating oil into the lubrication system, mainly including spray lubrication + two-axis center oil pipe center oil circuit lubrication or spray lubrication or two-axis center oil pipe center oil circuit lubrication. Both lubrication methods have oil stirring loss on the gears.

[0004] For the gearbox assembly using splash (oil immersion) lubrication, in order to meet the heat dissipation and lubrication requirements of the gear meshing pair, the gearbox oil level is often set near the axis of the intermediate shaft. The gears on the intermediate shaft are all immersed in the lubricating oil. The gear oil immersion depth is very deep, the oil churning loss is very large, and the gearbox transmission efficiency is very low.

[0005] For the gearbox assembly using splash (oil immersion) lubrication + active lubrication, due to the active lubrication of the gear meshing pair of the gearbox, the oil level can be set slightly lower than that of the gearbox assembly with splash lubrication, the gear oil immersion depth is reduced, the gear meshing pair oil stirring loss is lower than that of the gearbox assembly with splash lubrication, and the gearbox transmission efficiency is improved compared with the gearbox assembly with splash lubrication. However, there is still a certain amount of oil stirring loss, and the gearbox transmission efficiency is improved compared with the assembly with splash lubrication, but it is still not high.

[0006] The specification of Chinese invention patent CN113251133A discloses an oil baffle plate for achieving unequal oil levels, which is arranged adjacent to the intermediate shaft assembly, on which the first large gear, the second large gear and the control gear are fixedly mounted, and the oil baffle plate is an arc-shaped shell, which is divided into a stepped small diameter shell and a large diameter shell; the small diameter shell is coated on the outside of the control gear, and the large diameter shell is coated on the outside of the first large gear and the second large gear; when the intermediate shaft assembly rotates, and the oil inlet speed of the oil baffle plate is equal to the oil throwing speed of the first large gear and the second large gear; the oil surface thickness of the inner wall of the large diameter shell reaches the main set thickness. This lubrication scheme discloses that when the intermediate shaft gear rotates, the lubricating oil inside the oil baffle plate is stirred to the outside of the oil baffle plate, and the lubricating oil outside the oil baffle plate flows back to the oil baffle plate through the small holes at the bottom of the oil baffle plate. The oil level inside the oil baffle changes with the speed of the gear. The oil baffle is installed inside the gearbox to separate the oil level of the lubricating oil, so that the lubricating oil inside the gearbox has unequal oil levels. While ensuring the lubrication of the control gear and the remaining small gears, the first large gear and the second large gear will not intrude too deep into the oil level, thereby reducing the oil stirring loss of large diameter gears and improving the transmission efficiency of the gearbox. However, it should be pointed out that the oil immersion depth of the gears in this technical solution is uncertain, the intermediate shaft gears are always immersed in the oil and stirring the oil, and the gearbox gears always have oil stirring losses, so the transmission efficiency of the gearbox cannot reach the maximum. Furthermore, the working principle of the gearbox of CN113251133A is that before the intermediate shaft assembly rotates, the oil levels inside and outside the oil baffle are consistent; after the intermediate shaft assembly rotates, due to the barrier effect of the oil baffle, the oil inlet speed of the oil baffle is less than the oil throwing speed of the first large gear and the second large gear; as time goes on, the oil on the inner wall of the oil baffle will become less and less, and as the oil decreases, the oil throwing speed of the first large gear and the second large gear will become smaller and smaller, until the outward oil throwing speed is equal to the inward oil inlet speed, reaching a dynamic balance, and the oil thickness of the inner wall of the oil baffle will remain unchanged; in the actual design process, the oil seepage gap or the size of the oil seepage hole can be adjusted to adjust the oil seepage gap or the size of the oil seepage hole. Dynamic balance, ingenious design, flexible and convenient adjustment; that is, the lubricating oil in the gearbox always flows into the oil baffle through the oil seepage hole from the bottom oil chamber of the gearbox housing located on the lower side of the oil baffle, that is, a semi-closed oil baffle is installed around the intermediate shaft gear inside the housing to separate the internal oil chamber of the oil baffle from the external oil chamber, the oil level outside the oil baffle is higher than the oil level inside the oil baffle, and when the intermediate shaft gear rotates, the lubricating oil inside the oil baffle is stirred to the outside of the oil baffle, and the lubricating oil outside the oil baffle flows back to the oil baffle through the small holes at the bottom of the oil baffle. The defects of this scheme are: the oil immersion depth of the gear is uncertain, the intermediate shaft gear is always immersed in the oil and stirred, the gearbox gear always has oil stirring loss, and the transmission efficiency of the gearbox cannot reach the maximum.

[0007] Furthermore, the specification of Chinese utility model patent CN211501591U discloses a transmission for automobile, comprising a rotating assembly and an oil distribution tank, wherein the rotating assembly comprises an intermediate shaft and a small gear, a first large gear and a second large gear arranged on the intermediate shaft; a first oil storage chamber and a second oil storage chamber are provided in the oil distribution tank along the axial direction of the intermediate shaft, the bottoms of the first large gear and the second large gear are respectively accommodated in the first oil storage chamber and the second oil storage chamber, the bottoms of the first large gear and the second large gear are respectively immersed in the lubricating oil in the first oil storage chamber and the second oil storage chamber, and a first channel for the lubricating oil to enter the first oil storage chamber is formed between the first oil storage chamber and the rotating assembly; at the same time, the heights of both sides of the oil distribution tank are higher than the original oil level, so as to prevent the lubricating oil outside the oil distribution tank from entering the first oil storage chamber and the second oil storage chamber from both sides of the oil distribution tank, so that when the first large gear and the second large gear rotate, the lubricating oil in the first oil storage chamber and the second oil storage chamber is discharged from both sides of the oil distribution tank, thereby reducing the oil immersion depth of the first large gear and the second large gear, reducing the oil stirring loss of the large gear, and improving the transmission efficiency of the transmission. However, it is still impossible to determine the oil immersion depth of the gears, so the intermediate shaft gears may still be immersed in the oil and stirred, and the gearbox gears always have oil stirring losses, and the gearbox transmission efficiency cannot reach the maximum.

[0008] Furthermore, Chinese invention patent CN202110475258.7 "Variable oil level gearbox lubrication system" and Chinese invention patent CN202110476963.9 "Gearbox lubrication method" disclose variable liquid level gearbox lubrication methods, both of which require a separate oil collecting space to be set on the gearbox, and the oil level in the gearbox housing is adjusted by opening the safety valve. The initial oil level of the gearbox is very high, the amount of refueling is large, and the cost of lubricating oil is high; the oil storage space occupies a large space, resulting in an increase in the volume and weight of the gearbox; a separate pipeline connection and seal are required between the oil collecting pool and the oil circuit of the lubrication system, which increases the manufacturing cost and also poses a reliability risk. Summary of the invention

[0009] In view of the technical problems existing in the prior art, the present invention provides a lubrication structure and a gearbox for controlling the oil level height of the gearbox to improve the transmission efficiency. The structure is not only simple, but also can automatically adjust the height of the gears inside the gearbox immersed in the lubricating oil according to the input speed of the gearbox, and automatically switch between spray lubrication, oil immersion lubrication, and spray lubrication + oil immersion lubrication conditions, thereby ensuring the reliability of the gearbox operation, minimizing the gear oil stirring loss, and improving the transmission efficiency of the gearbox.

[0010] The present invention discloses a lubrication structure for controlling the oil level height of a gearbox to improve transmission efficiency, comprising a gearbox housing, wherein an intermediate shaft assembly, a spray lubrication unit and an oil pump are arranged in the gearbox housing, at least one gear is arranged on the intermediate shaft assembly, an oil baffle plate is arranged between the gear and the bottom of the gearbox housing, the oil baffle plate is an arc-shaped shell, the oil baffle plate envelopes the outer side of the gear, and is characterized in that: a first edge of the oil baffle plate extending along the axial direction of the intermediate shaft assembly is sealed and fixedly connected to a first inner wall of the gearbox housing, a gap is arranged between a second edge of the oil baffle plate extending along the axial direction of the intermediate shaft assembly and the second inner wall of the gearbox housing, and a height of the second edge is equal to a tooth root circle of a gear with the smallest diameter among all gears.

[0011] In a preferred embodiment of the present invention, the oil baffle comprises an arc-shaped shell, and the diameter of the arc-shaped shell is greater than the tooth top height of the gear with the largest diameter among all the gears.

[0012] In a preferred embodiment of the present invention, the oil baffle comprises a plurality of arcuate shells, at least two of the arcuate shells have different diameters, each arcuate shell encloses at least one gear, and the height of the second edge of each arcuate shell is equal to the root circle of the gear with the smallest diameter located therein.

[0013] In a preferred embodiment of the present invention, the arcuate upper end surface of the oil baffle plate constitutes an upper oil collecting chamber, and the arcuate lower end surface of the oil baffle plate and the bottom of the gearbox housing constitute a lower oil collecting chamber, and the upper oil collecting chamber and the lower oil collecting chamber are connected only through the gap between the second edge and the second inner wall.

[0014] In a preferred embodiment of the present invention, the lower oil collecting chamber is connected to the oil suction port of the oil pump, the oil pump rotor of the oil pump is connected to the end of the intermediate shaft assembly, the oil pump is driven to pump oil through the spline on the intermediate shaft assembly, and the oil outlet of the oil pump is connected to the spray lubrication unit through the oil channel to provide lubricating oil for spray lubrication.

[0015] In a preferred embodiment of the present invention, when the gearbox is initially refueled, the oil level line H1 is lower than the tooth top circle of the gear with the largest diameter among all the gears, and the oil level line H1 is higher than the oil suction port of the oil suction filter. The oil suction filter is installed at the oil suction port of the oil pump and is connected to the spray lubrication unit through the oil pump; when the gearbox is running, the intermediate shaft assembly drives the oil pump to start working, and the oil pump filters the lubricating oil in the lower oil collecting chamber through the oil suction filter and then pumps it into the spray lubrication unit. The oil spray hole of the spray lubrication unit is directly opposite to the gear meshing point, and the lubricating oil sprayed by the spray lubrication unit is sprayed onto the gear surface. A part of the lubricating oil is directly thrown by the gear to the second inner wall and flows to the lower oil collecting chamber along the second inner wall, and another part of the lubricating oil flows to the upper oil collecting chamber; when the oil level of the upper oil collecting chamber rises and is higher than the tooth top circle of the gear with the largest diameter, the gear rotates to stir up the lubricating oil in the upper oil collecting chamber, and the lubricating oil is thrown to the second inner wall along the second edge, and then flows to the lower oil collecting chamber through the gap between the second edge and the second inner wall.

[0016] In a preferred embodiment of the present invention, the amount of lubricating oil pumped out by the oil pump is Q 泵出 , by setting the oil pump eccentricity, rotor thickness and other parameters to control the amount of lubricating oil pumped out by the oil pump Q 泵出 ; The amount of lubricating oil pumped out by the oil pump Q 泵出 =Q is equal to the total amount of oil flowing into the upper oil collecting chamber through the spray lubrication unit; the total amount of oil thrown from all gears on the intermediate shaft assembly is Q 甩出 ;When initially setting the oil pump oil volume, ensure that Q 泵出初 >Q 甩出初 .

[0017] In a preferred embodiment of the present invention, when the gearbox operates in a low speed range, the intermediate shaft input speed is low, and the amount of lubricating oil pumped out by the oil pump is Q 泵出低 , the amount of lubricating oil pumped out by the oil pump is Q 泵出低 The lubrication and heat dissipation requirements of the gear meshing pair are not met. At this time, the total amount of oil thrown from all gears on the intermediate shaft assembly is Q 甩出低 , Q 泵出低 >Q 甩出低 , that is, the amount of lubricating oil flowing into the upper oil collecting chamber Q 泵出低 Greater than the amount of lubricating oil Q thrown away by the gear churning oil 甩出低 , the oil level of the upper oil collecting chamber rises from H1 to H2, the same height as the second edge of the oil baffle plate, and the excess lubricating oil flows along the gap between the second edge of the oil baffle plate and the second inner wall to the lower oil collecting chamber. At this time, the oil level H2 of the gearbox is the same as the height of the right edge of the baffle plate, and the oil immersion depth is the minimum gear root circle. The gears on the intermediate shaft assembly are immersed in the lubricating oil of the upper oil collecting chamber. At this time, the lubrication methods of the gear pair are spray lubrication and oil immersion lubrication.

[0018] In a preferred embodiment of the present invention, when the gearbox operates in a high speed range, the gearbox input speed increases, and the oil pumping amount of the oil pump increases. At this time, the amount of lubricating oil pumped out by the oil pump is Q 泵出高 , the amount of lubricating oil pumped out by the oil pump is Q 泵出高 To meet the needs of gear meshing pair lubrication and heat dissipation, the intermediate shaft assembly has a high speed, the gears on the intermediate shaft assembly have a strong oil throwing ability, and the amount of lubricating oil flowing into the upper oil collecting chamber is Q 泵出高 <The amount of lubricating oil thrown away by the gear churning oil Q 甩出高 , the oil level H3 of the upper oil collecting chamber drops to a level close to or lower than the tooth top height of the gear with the largest gear diameter. At this time, the lubrication method of the gear pair is spray lubrication, the gear pair basically does not stir the oil, the stirring loss is extremely low, and the transmission efficiency reaches the maximum value.

[0019] In a preferred embodiment of the present invention, the low speed range is transmission input speed ≤ engine idle speed; the high speed range is engine idle speed < transmission input speed ≤ engine rated speed.

[0020] In a preferred embodiment of the present invention, the gearbox housing and the oil baffle plate are cast as an integral structure, or the gearbox housing and the oil baffle plate are cast separately and then welded and fixed, or the gearbox housing and the oil baffle plate are assembled and fixed as separate structures.

[0021] In a preferred embodiment of the present invention, the spray lubrication unit comprises a gear surface spray oil pipe and / or a dual-axis center oil pipe.

[0022] In a preferred embodiment of the present invention, the oil hole of the central oil pipe of the two shafts is connected to the central oil chamber of the two shafts, and oil outlet holes are provided on the two shafts. The lubricating oil entering the central oil pipe of the two shafts lubricates the bearings through the oil outlet holes on the two shafts and then flows to the upper oil collecting chamber.

[0023] The present invention also discloses a gearbox, which comprises the aforementioned lubrication structure for controlling the gearbox oil level to improve transmission efficiency.

[0024] The beneficial effects of the present invention are as follows: the present invention is not only simple in structure, but also can automatically adjust the height of the gears inside the gearbox immersed in the lubricating oil according to the input speed of the gearbox, and automatically switch between spray lubrication, oil immersion lubrication, and spray lubrication + oil immersion lubrication conditions, which ensures the reliability of the gearbox operation and minimizes the gear oil stirring loss, thereby improving the transmission efficiency of the gearbox. The present invention creatively seals and fixes a first edge of the oil baffle plate extending axially along the intermediate shaft assembly to a first inner wall of the gearbox housing, and a gap is provided between a second edge of the oil baffle plate extending axially along the intermediate shaft assembly and a second inner wall of the gearbox housing, and the height of the second edge is equal to the root circle of the gear with the smallest diameter among all the gears. The oil immersion depth of the gears of the gearbox can be controlled by controlling the height of the right edge of the baffle, and the amount of lubricating oil pumped out by the oil pump Q can be controlled by setting parameters such as the eccentricity of the oil pump and the thickness of the rotor. 泵出 . Initially set the oil pump oil volume to ensure Q 泵出初 >Q 甩出初 . By controlling the relationship between the gearbox input speed, the oil intake of the spray lubrication (the oil pumping amount of the oil pump), the oil throwing amount of the gear, and the height of the right edge of the oil baffle, when the gearbox is running in the high speed range, the gear meshing pair has almost no oil stirring loss, and the gearbox transmission efficiency is maximized. The gearbox can also be operated in the low speed range. By adding the method of oil immersion lubrication of the gear meshing pair, the problem that the gear meshing pair cannot meet the heat dissipation and lubrication requirements by only spray lubrication or two-axis center oil circuit lubrication or spray lubrication + two-axis center oil circuit lubrication is solved. That is, the transmission efficiency of the gearbox when working in the economic speed range is improved, and the reliability of the gearbox when working in the low speed range is guaranteed;

[0025] Furthermore, the oil baffle of the present invention comprises an arc-shaped shell, the diameter of which is greater than the tooth top height of the gear with the largest diameter among all the gears. This solution is easy to manufacture and assemble, and is applicable to the case where there are multiple gears with similar diameters.

[0026] Furthermore, the oil baffle of the present invention may also include a plurality of arc-shaped shells, at least two of which have different diameters, each of which envelops at least one gear, and the height of the second edge of each arc-shaped shell is equal to the root circle of the gear with the smallest inner diameter, that is, the stepped arc-shaped shell of the oil baffle has a structure similar to that disclosed in CN113251133A or CN211501591U, which is suitable for a plurality of gears with large diameter differences. Although this technical solution is not conducive to processing and manufacturing, it is more conducive to the precise control of oil immersion lubrication;

[0027] Furthermore, the arc-shaped upper end surface of the oil baffle plate forms an upper oil collecting chamber, and the arc-shaped lower end surface of the oil baffle plate and the bottom of the gearbox housing form a lower oil collecting chamber. The upper oil collecting chamber and the lower oil collecting chamber are connected only through the gap between the second edge and the second inner wall. The control of this gap can effectively adjust the height of the oil that can be stored in the upper oil collecting chamber, thereby ensuring that when the gearbox is running in a high-speed range, the gear meshing pair has almost no oil stirring loss, and the gearbox transmission efficiency is maximized. It can also be achieved when the gearbox is running in a low-speed range by adding oil immersion lubrication for the gear meshing pair to solve the problem that the gear meshing pair cannot meet the heat dissipation and lubrication requirements by only relying on spray lubrication or two-axis center oil circuit lubrication or spray lubrication + two-axis center oil circuit lubrication;

[0028] Furthermore, the present invention divides the input speed of the gearbox into a low speed range and a high speed range, and realizes reasonable control of the oil level of the gearbox according to the speed; by controlling the relationship between the input speed of the gearbox, the oil intake of the spray lubrication (the oil pumping amount of the oil pump), the oil throwing amount of the gear, and the height of the right edge of the oil baffle, the present invention can make the gear meshing pair have almost no oil stirring loss when the gearbox is running in the high speed range, and the transmission efficiency of the gearbox is maximized. It can also be achieved that when the gearbox is running in the low speed range, by adding the method of oil immersion lubrication of the gear meshing pair, the problem that the gear meshing pair cannot meet the heat dissipation and lubrication requirements by only spray lubrication or two-axis center oil circuit lubrication or spray lubrication + two-axis center oil circuit lubrication can be solved. That is, the transmission efficiency of the gearbox when working in the economic speed range is improved, and the reliability of the gearbox when working in the low speed range is guaranteed;

[0029] Furthermore, when the middle shell structure of the present invention allows, the baffle can be directly cast on the shell and formed in one step. This technical solution not only effectively saves the manufacturing cost of the gearbox shell, but also has the advantages of firm and reliable installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is an isometric view of a lubrication structure for controlling the oil level of a gearbox and improving transmission efficiency according to the present invention (with the intermediate shaft assembly hidden);

[0031] Figure 2 It is a front view of a lubrication structure for controlling the oil level of a gearbox and improving transmission efficiency according to the present invention;

[0032] Figure 3 It is a front view of the initial state of a gearbox of a lubrication structure for controlling the gearbox oil level to improve transmission efficiency according to the present invention; (initial state oil level height line H1);

[0033] Figure 4 It is a side view of the initial state of a gearbox of a lubrication structure for controlling the gearbox oil level to improve transmission efficiency according to the present invention; (initial state oil level height line H1);

[0034] Figure 5 This is a front view of a gearbox in a low-speed state of a lubrication structure for controlling the gearbox oil level to improve transmission efficiency according to the present invention; (low-speed state oil level line H2);

[0035] Figure 6 It is a side view of a gearbox in a low speed state of a lubrication structure for controlling the gearbox oil level to improve transmission efficiency of the present invention; (low speed state oil level line H2);

[0036] Figure 7 It is a front view of a gearbox in a high-speed state of a lubrication structure for controlling the gearbox oil level to improve transmission efficiency of the present invention; (high-speed state oil level line H3);

[0037] Figure 8 It is a side view of a gearbox in a high-speed state of a lubrication structure for controlling the gearbox oil level to improve transmission efficiency according to the present invention; (high-speed state oil level line H3);

[0038] Fig. 9 It is a schematic diagram of an oil pump of a lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to the present invention;

[0039] Fig.10 It is a schematic diagram of an oil suction filter screen of a lubrication structure for controlling the oil level of a gearbox and improving transmission efficiency according to the present invention;

[0040] In the figure, 1-gearbox housing; 2-intermediate shaft assembly; 3-tooth surface spray oil pipe; 4-second shaft center oil pipe; 5-oil baffle; 6-oil pump; 7-oil suction filter; 1.1-first inner wall; 1.2-second inner wall; 5.1-first edge; 5.2-second edge, 6.1-oil pump suction port, 6.2-oil pump outlet, 6.3-oil pump rotor. DETAILED DESCRIPTION

[0041] The technical solution of the present invention (including the preferred technical solution) is further described in detail below by means of the accompanying drawings and by listing some optional embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0043] Further, in this application, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0044] The present invention discloses a lubrication structure for controlling the oil level height of a gearbox to improve transmission efficiency, comprising a gearbox housing 1, in which an intermediate shaft assembly 2, a gear surface spray oil pipe 3 and / or a second shaft center oil pipe 4 are arranged (the gear surface spray oil pipe 3 and / or the second shaft center oil pipe 4 can be arranged as needed, that is, the present invention has three combination schemes, technical scheme 1: the gear surface spray oil pipe 3 is arranged separately; technical scheme 2: the second shaft center oil pipe 4 is arranged separately; technical scheme 3: the gear surface spray oil pipe 3 and / or the second shaft center oil pipe 4 are arranged simultaneously), an oil channel integrated on the housing, and an oil pump 6 and an oil suction device, the end of the intermediate shaft assembly 2 is connected to an oil pump 6, the oil pump 6 provides lubricating oil for spray lubrication, at least one gear is arranged on the intermediate shaft assembly, an oil baffle plate 5 is arranged between the gear and the bottom of the gearbox housing 1, the oil baffle plate 5 is an arc-shaped shell, the oil baffle plate 5 is enveloped on the outside of the gear, a first edge 5.1 of the oil baffle plate 5 extending along the axial direction of the intermediate shaft assembly is sealed and fixedly connected to the first inner wall 1.1 of the gearbox housing 1, and a gap (from the second edge 5.2 of the oil baffle plate 5 extending along the axial direction of the intermediate shaft assembly) is arranged between the second inner wall 1.2 of the gearbox housing 1. Figure 1 and Figure 2 It can be seen that the left end of the oil baffle plate 5 is sealed with the housing, the right edge of the oil baffle plate 5 is open, and a gap is left between the oil baffle plate 5 and the inner wall of the gearbox housing). The height of the second edge 5.2 is equal to the root circle of the gear with the smallest diameter among all gears. The oil baffle plate 5 divides the bottom oil chamber of the gearbox housing into an upper oil chamber and a lower oil chamber. The oil suction device sucks oil from the lower oil chamber of the housing, and the oil pump pumps the lubricating oil into the oil circuit of the sliding system. The tooth surface spray oil pipe 3 and the second axis center oil pipe 4 are arranged in parallel on the oil channel after the lubricating oil flows from the bottom of the gearbox housing through the oil suction filter and the oil pump. The tooth surface spray oil pipe 3 is provided with a spray oil hole facing the gear meshing pair, and the second axis center oil pipe 4 is provided with a second axis center oil pipe oil outlet hole.

[0045] In a preferred embodiment of the present invention, the oil baffle 5 includes an arc-shaped shell, that is, a cylindrical groove structure is arranged in the arc-shaped shell, and the diameter of the arc-shaped shell is larger than the tooth top height of the gear with the largest diameter among all gears. This structure is suitable for multiple gears and the diameters of the multiple gears are not much different.

[0046] In a preferred embodiment of the present invention, the oil baffle 5 includes a plurality of arcuate shells, at least two of which have different diameters, each of which envelops at least one gear, and the height of the second edge 5.2 of each arcuate shell is equal to the root circle of the gear with the smallest inner diameter. The stepped arcuate shell of the oil baffle of this technical solution has a structure similar to that disclosed in CN113251133A or CN211501591U, which is suitable for situations where there are multiple gears with large differences in diameter. Although this technical solution is not conducive to processing and manufacturing, it is more conducive to the precise control of oil immersion lubrication.

[0047] In a preferred embodiment of the present invention, the arcuate upper end surface of the oil baffle plate 5 constitutes an upper oil collecting chamber, and the arcuate lower end surface of the oil baffle plate 5 and the bottom of the gearbox housing 1 constitute a lower oil collecting chamber, and the upper oil collecting chamber and the lower oil collecting chamber are connected only through the gap between the second edge 5.2 and the second inner wall 1.2.

[0048] In a preferred embodiment of the present invention, the lower oil collecting chamber is connected to the oil suction port 6.1 of the oil pump, the oil pump rotor 6.3 is connected to the end of the intermediate shaft assembly 2, the oil pump is driven to pump oil through the spline on the intermediate shaft assembly 2, and the oil outlet 6.2 of the oil pump is connected to the gear surface spray oil pipe 3 and the second shaft center oil pipe 4 through the oil channel to provide lubricating oil for spray lubrication.

[0049] In a preferred embodiment of the present invention, Figure 3-4As shown, when the gearbox is initially refueled, the oil level line H1 is lower than the tooth top circle of the gear with the largest diameter among all the gears, and the oil level line H1 is higher than the oil suction port of the oil suction filter. The oil suction filter is installed at the oil suction port of the oil pump, and is connected with the gear surface spray oil pipe and the second shaft center oil pipe or the spray oil pipe or the second shaft center oil pipe through the oil pump; when the gearbox is running, the intermediate shaft assembly 2 drives the oil pump to start working, and the oil pump filters the lubricating oil in the lower oil collecting chamber through the oil suction filter and then pumps it into the gear surface spray oil pipe 3 and / or the second shaft center oil pipe 4. The oil injection hole of the gear surface spray oil pipe 3 is directly opposite to the gear meshing point, and the lubricating oil sprayed from the gear surface spray oil pipe 3 is sprayed onto the gear surface, and a part of it The lubricating oil is thrown directly by the gear to the second inner wall 1.2 and flows along the second inner wall 1.2 to the lower oil collecting chamber, and another part of the lubricating oil flows into the upper oil collecting chamber; the oil hole of the central oil pipe of the second shaft is connected with the central oil chamber of the second shaft, and the two shafts are provided with oil outlet holes. The lubricating oil entering the central oil pipe of the second shaft lubricates the bearings through the oil outlet holes on the two shafts and then flows to the upper oil collecting chamber. When the oil level in the upper oil collecting chamber rises and is higher than the tooth top circle of the gear with the largest diameter, the gear rotates to stir up the lubricating oil in the upper oil collecting chamber, and the lubricating oil is thrown along the second edge 5.2 to the second inner wall 1.2, and then flows to the lower oil collecting chamber through the gap between the second edge 5.2 and the second inner wall 1.2.

[0050] In a preferred embodiment of the present invention, the oil pumping amount of the oil pump is Q 泵出 By setting the oil pump eccentricity, rotor thickness and other parameters, the amount of lubricating oil pumped out by the oil pump can be controlled. 泵出 The amount of lubricating oil pumped out by the oil pump is equal to the total amount of oil flowing into the upper oil collecting chamber through the spray oil pipe and the second axis center oil pipe. At this time, the total amount of oil thrown out of all gears on the intermediate shaft assembly is Q 甩出 When setting the initial oil pump volume, ensure that Q 泵出初 >Q 甩出 early.

[0051] In a preferred embodiment of the present invention, Figure 5-6 As shown in the figure, when the gearbox works in the low speed range, the gearbox input speed is low, the oil pump is insufficient, and the amount of lubricating oil sprayed through the spray oil pipe is small. It is difficult to meet the heat dissipation requirements of the gear meshing pair by only spraying the lubricating oil on the gear surface. However, due to Q 泵出低 >Q 甩出低, the amount of lubricating oil flowing into the upper oil collecting chamber is greater than the amount of lubricating oil thrown away by the gear oil stirring, and the oil level height H2 of the upper oil collecting chamber rises to the same height as the second edge 5.2. The excess lubricating oil will flow to the lower oil collecting chamber along the gap between the second edge 5.2 and the second inner wall 1.2. At this time, the oil level height H2 of the gearbox is the same as the height of the right edge of the oil baffle, and the gear tooth tops on the intermediate shaft assembly 2 are immersed in the lubricating oil in the upper oil collecting chamber. At this time, the lubrication method of the gear pair is spray lubrication + oil immersion lubrication. That is, when the speed of the gearbox is low, the problem of insufficient spray lubricating oil is compensated by oil immersion lubrication, and the gear lubrication and heat dissipation requirements are met by the combined lubrication method of spray lubrication + oil immersion lubrication. At this time, the oil level height of the upper oil chamber is consistent with the height of the right edge of the oil baffle, that is, the oil immersion depth of the gearbox gear can be controlled by controlling the height of the right edge of the oil baffle.

[0052] In a preferred embodiment of the present invention, Figure 7-8 As shown in the figure, when the gearbox works in the high speed range, the gearbox input speed increases, the oil pumping amount increases, and the lubricating oil flow rate pumped out by the oil pump is Q 泵出高 The pumped lubricating oil is sprayed on the gears and bearings through the gear surface spray oil pipe 3 and the second axis center oil circuit 4. The amount of lubricating oil sprayed is Q 泵出高 It can meet the needs of gear meshing pair lubrication and heat dissipation. At this time, the intermediate shaft assembly 2 has a high speed, the gears on the intermediate shaft assembly 2 have a strong oil throwing ability, and the amount of lubricating oil flowing into the upper oil collecting chamber is Q 泵出高 Less than the amount of lubricating oil Q thrown away by the gear churning oil 甩出高 , that is, Q 泵出高 <Q 甩出高 At this time, the oil level H3 of the upper oil collecting chamber is close to or lower than the tooth top height of the gear with the largest diameter among all gears, that is, the oil level H3 of the upper oil collecting chamber is near the tooth top circle of the intermediate shaft gear. At this time, the lubrication method of the gear pair is spray lubrication, that is, when the speed of the gearbox increases, the amount of lubricating oil Q flowing into the upper oil chamber of the housing 泵出高 Less than the amount of lubricating oil Q thrown away by the gear churning oil 甩出高 The gear pair meets the gear lubrication and heat dissipation requirements by spraying lubrication. At this time, the oil level H3 of the upper oil chamber is near the top circle of the intermediate shaft gear, the gear pair basically does not stir the oil, the oil stirring loss is extremely low, and the transmission efficiency reaches the maximum value.

[0053] In a preferred embodiment of the present invention, the low speed range is transmission input speed ≤ engine idle speed; the high speed range is engine idle speed < transmission input speed ≤ engine rated speed.

[0054] In a preferred embodiment of the present invention, the gearbox housing 1 and the oil baffle plate 5 are cast as an integral structure, or the gearbox housing 1 and the oil baffle plate 5 are cast separately and then welded and fixed, or the gearbox housing 1 and the oil baffle plate 5 are assembled and fixed as a split structure.

[0055] The variable oil surface stratified lubrication structure involved in the present invention adds an oil baffle in the middle of the gearbox housing to divide the housing inner cavity into two upper and lower oil chambers. By controlling the relationship between the gearbox input speed, the oil intake of the spray lubrication (the oil pumping amount of the oil pump), the oil throwing amount of the gear, and the height of the right edge of the oil baffle, when the gearbox is running in the high speed range, there is almost no oil stirring loss in the gear pair, and the transmission efficiency of the gearbox is maximized. It can also be achieved when the gearbox is running in the low speed range by adding the gear pair immersion lubrication method to solve the problem that the gear pair cannot meet the heat dissipation and lubrication requirements by only spray lubrication or two-axis center oil circuit lubrication or spray lubrication + two-axis center oil circuit lubrication. That is, the transmission efficiency of the gearbox when working in the high speed range is improved, and the reliability of the gearbox when working in the low speed range is guaranteed.

[0056] The present invention also discloses a gearbox, which comprises the aforementioned lubrication structure for controlling the gearbox oil level to improve transmission efficiency.

[0057] The invention also discloses a vehicle, which comprises the above-mentioned gearbox.

[0058] It should be pointed out that the gearbox housing 1 which is not described in detail in the present invention is provided with an intermediate shaft assembly 2, a gear surface spray oil pipe 3, a second shaft center oil pipe 4, an oil channel integrated on the housing, an oil pump and an oil suction device structure which can refer to patents such as CN111043294A.

[0059] Those skilled in the art will readily appreciate that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, combinations, replacements, improvements, etc. made within the spirit and principles of the present invention are included within the protection scope of the present invention.

Claims

1. A lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency, comprising a gearbox housing (1), wherein an intermediate shaft assembly (2), a spray lubrication unit and an oil pump (6) are arranged in the gearbox housing (1), at least one gear is arranged on the intermediate shaft assembly, an oil baffle plate (5) is arranged between the gear and the bottom of the gearbox housing (1), the oil baffle plate (5) is an arc-shaped housing, and the oil baffle plate (5) is enveloping the outer side of the gear, and is characterized in that: A first edge (5.1) of the oil baffle plate (5) extending along the axial direction of the intermediate shaft assembly is sealed and fixedly connected to a first inner wall (1.1) of the gearbox housing (1); a gap is provided between a second edge (5.2) of the oil baffle plate (5) extending along the axial direction of the intermediate shaft assembly and a second inner wall (1.2) of the gearbox housing (1); the height of the second edge (5.2) is equal to the tooth root circle of the gear with the smallest diameter among all the gears; when the gearbox is initially refueled, the oil level line H1 is lower than the tooth top circle of the gear with the largest diameter among all the gears, and the oil level line H1 is higher than the oil suction port of the oil suction filter, which is installed at the oil suction port of the oil pump and is connected to the spray lubrication unit through the oil pump; when the gearbox is running, the intermediate shaft assembly (2) The oil pump is driven to start working. The oil pump filters the lubricating oil in the lower oil collecting chamber through the oil suction filter and then pumps it into the spray lubrication unit. The oil spray hole of the spray lubrication unit is directly opposite to the gear meshing point. The lubricating oil sprayed by the spray lubrication unit is sprayed onto the gear surface. A part of the lubricating oil is directly thrown by the gear to the second inner wall (1.2) and flows along the second inner wall (1.2) to the lower oil collecting chamber, and another part of the lubricating oil flows into the upper oil collecting chamber. When the oil level in the upper oil collecting chamber rises and is higher than the tooth top circle of the gear with the largest diameter, the gear rotates to stir up the lubricating oil in the upper oil collecting chamber. The lubricating oil is thrown along the second edge (5.2) to the second inner wall (1.2), and then flows into the lower oil collecting chamber through the gap between the second edge (5.2) and the second inner wall (1.2).

2. The lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to claim 1, characterized in that: The oil baffle (5) comprises an arc-shaped shell, the diameter of which is greater than the tooth top height of the gear with the largest diameter among all the gears.

3. The lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to claim 1, characterized in that: The oil baffle (5) comprises a plurality of arc-shaped shells, at least two of which have different diameters, each arc-shaped shell enveloping at least one gear, and the height of the second edge (5.2) of each arc-shaped shell being equal to the root circle of the gear with the smallest diameter located therein.

4. The lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to claim 1, characterized in that: The arc-shaped upper end surface of the oil baffle plate (5) forms an upper oil collecting chamber, and the arc-shaped lower end surface of the oil baffle plate (5) and the bottom of the gearbox housing (1) form a lower oil collecting chamber, and the upper oil collecting chamber and the lower oil collecting chamber are connected only through the gap between the second edge (5.2) and the second inner wall (1.2).

5. The lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to claim 1, characterized in that: The lower oil collecting chamber is connected to the oil suction port (6.1) of the oil pump, the oil pump rotor (6.3) of the oil pump is connected to the end of the intermediate shaft assembly (2), the oil pump is driven to pump oil through the spline on the intermediate shaft assembly (2), and the oil outlet (6.2) of the oil pump is connected to the spray lubrication unit through the oil channel to provide lubricating oil for spray lubrication.

6. The lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to claim 1, characterized in that: The amount of lubricating oil pumped out by the oil pump is Q 泵出 , by setting the oil pump eccentricity and rotor thickness parameters, the amount of lubricating oil pumped out by the oil pump Q is controlled 泵出 ; The amount of lubricating oil pumped out by the oil pump Q 泵出 = is equal to the total amount of oil flowing into the upper oil collecting chamber through the spray lubrication unit; the total amount of oil thrown off by all gears on the intermediate shaft assembly (2) is Q 甩出 ;When initially setting the oil pump oil volume, ensure that Q 泵出初 >Q 甩出初 .

7. The lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to claim 1, characterized in that: When the gearbox works in the low speed range, the intermediate shaft input speed is low, and the amount of lubricating oil pumped out by the oil pump is Q 泵出低 , the amount of lubricating oil pumped out by the oil pump is Q 泵出低 The requirements of lubrication and heat dissipation of the gear meshing pair are not met. At this time, the total amount of oil thrown off all the gears on the intermediate shaft assembly (2) is Q 甩出低 , Q 泵出低 >Q 甩出低 , that is, the amount of lubricating oil flowing into the upper oil collecting chamber Q 泵出低 Greater than the amount of lubricating oil Q thrown away by the gear churning oil 甩出低 The oil level of the upper oil collecting chamber rises from H1 to the same height H2 as the second edge (5.2) of the oil baffle plate, and the excess lubricating oil flows along the gap between the second edge (5.2) of the oil baffle plate and the second inner wall (1.2) to the lower oil collecting chamber. At this time, the oil level H2 of the gearbox is equal to the height of the right edge of the baffle plate, and the oil immersion depth is the minimum gear tooth root circle. The gears on the intermediate shaft assembly (2) are immersed in the lubricating oil of the upper oil collecting chamber. At this time, the lubrication method of the gear pair is spray lubrication and oil immersion lubrication.

8. The lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to claim 1, characterized in that: When the gearbox works in the high speed range, the gearbox input speed increases, the oil pumping amount increases, and the amount of lubricating oil pumped out by the oil pump is Q 泵出高 , the amount of lubricating oil pumped out by the oil pump is Q 泵出高 To meet the requirements of lubrication and heat dissipation of the gear meshing pair, the intermediate shaft assembly (2) has a high rotation speed, the gears on the intermediate shaft assembly (2) have a strong oil throwing ability, and the amount of lubricating oil flowing into the upper oil collecting chamber is Q 泵出高 <The amount of lubricating oil thrown away by the gear churning oil Q 甩出高 , the oil level H3 of the upper oil collecting chamber drops to below the tooth top height of the gear with the largest gear diameter. At this time, the lubrication method of the gear pair is spray lubrication, the gear pair basically does not stir the oil, the stirring oil loss is extremely low, and the transmission efficiency reaches the maximum value.

9. The lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to claim 7 or 8, characterized in that: The low speed range is transmission input speed ≤ engine idle speed; the high speed range is engine idle speed < transmission input speed ≤ engine rated speed.

10. The lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to claim 1, characterized in that: The gearbox housing (1) and the oil baffle plate (5) are cast to form an integral structure, or the gearbox housing (1) and the oil baffle plate (5) are cast separately and then welded and fixed, or the gearbox housing (1) and the oil baffle plate (5) are assembled and fixed as separate structures.

11. The lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to claim 1, characterized in that: The spray lubrication unit comprises a gear surface spray oil pipe (3) and / or a two-axis center oil pipe (4).

12. The lubrication structure for controlling the oil level of a gearbox to improve transmission efficiency according to claim 11, characterized in that: The oil hole of the central oil pipe (4) of the second shaft is connected to the central oil chamber of the second shaft. The second shaft is provided with an oil outlet hole. The lubricating oil entering the central oil pipe (4) of the second shaft lubricates the bearings through the oil outlet hole on the second shaft and then flows to the upper oil collecting chamber.

13. A gearbox, characterized in that: It comprises a lubrication structure for controlling the oil level height of a gearbox to improve transmission efficiency as described in any one of claims 1 to 12.

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