Oil-air lubrication cooling device and method for a gear transmission

Abstract

The application discloses an oil-gas lubrication cooling device and method for a gear transmission device, which comprises the following steps: using an oil-gas lubrication system to respectively provide an oil-gas mixture to a gear oil-gas nozzle and a bearing oil-gas nozzle, the gear oil-gas nozzle sprays the oil-gas mixture provided by the oil-gas lubrication system on a gear tooth surface, and the bearing oil-gas nozzle sprays the oil-gas mixture provided by the oil-gas lubrication system on each rolling bearing; using a compressed air system to respectively provide cooling air to an end face cooling nozzle and a top cooling nozzle, a fan cooling system sucks mixed hot air containing oil and gas in a transmission gear box through an air inlet to cool the gear, and the inside of the gear transmission box is in a negative pressure environment state; and the mixed hot air containing oil and gas is subjected to oil-gas separation and recovery through an oil-gas separator. The oil-gas lubrication cooling device and method greatly reduce the lubricating oil supply required by the gear transmission device, eliminate the problems of power loss caused by stirring oil, power loss caused by pumping and extruding, large heat generation and low operation efficiency.

Description

Technical Field

[0001] This invention belongs to the field of gearbox lubrication and cooling technology, and particularly relates to an oil-air lubrication and cooling device and method for gear transmission devices. Background Technology

[0002] The most common lubrication and cooling methods for gear transmissions are splash lubrication and oil spray lubrication. Splash lubrication involves immersing the gears in lubricating oil to a certain depth; the rotation of the gears carries the lubricating oil to the parts requiring lubrication, achieving both lubrication and cooling. Heat dissipation is achieved through heat exchange between the gear transmission surface and the external medium. Oil spray lubrication uses an oil pump to deliver lubricating oil at a certain pressure and speed, spraying it onto the parts of the gear transmission that require lubrication, achieving both lubrication and cooling. The continuously circulating lubricating oil exchanges heat with an external water-cooled or air-cooled heat exchanger, carrying away the heat from the gear transmission. Oil-air lubrication is a commonly used lubrication and cooling method for bearings. Lubricating oil is mixed with compressed air in an oil-air mixer, and the mixture is then supplied to the lubrication points. The lubrication points receive adequate lubrication while their heat is carried away by the compressed air, resulting in cooling. Oil-air lubrication is occasionally used in open gear transmissions, but it is not yet used for gear transmissions, especially closed gear transmissions.

[0003] For gear drives, only a small amount of lubricating oil is needed for lubrication. However, since gear drives also require cooling, a large amount of lubricating oil is needed to carry away heat and cool the gears. When using splash lubrication or spray lubrication, most of the lubricating oil is used for heat dissipation and cooling to reduce the operating temperature of the gears. The presence of a large amount of lubricating oil and oil-air mixture inside the gear drive inevitably causes the rotating parts to churn the oil and the oil-air mixture, generating heat through friction. This results in power losses due to churning and wind resistance. Simultaneously, excess lubricating oil carried to the meshing side and discharged from the disengaging side causes the gears to exert a squeezing and pumping effect on the lubricating oil, further increasing power loss and reducing gear operating efficiency, thus increasing energy consumption. The use of large amounts of lubricating oil inevitably increases the operating and maintenance costs of gear drives, and oil leakage during use also causes environmental pollution. Summary of the Invention

[0004] The purpose of this invention is to provide an oil-air lubrication and cooling device and method for gear transmission devices. This invention significantly reduces the amount of lubricating oil required for the operation of gear transmission devices, eliminates the power losses from oil churning and pumping / extrusion caused by traditional splash lubrication and oil spray lubrication, and avoids the problems of high heat generation and low operating efficiency in gear transmission devices. To achieve the above objectives, this invention employs the following technical effects:

[0005] According to one aspect of the present invention, an oil-air lubrication and cooling device for a gear transmission device is provided. The oil-air lubrication and cooling device includes an oil-air lubrication system, a fan cooling system, a compressed air system, and gear oil-air nozzles and bearing oil-air nozzles disposed on a transmission gearbox. A horizontal air inlet and a side air inlet for purifying the intake of cooling air are respectively disposed on both sides of the transmission gearbox. An air intake for drawing in oil-air is disposed at the top of the transmission gearbox. One or more top cooling nozzles are disposed inside the transmission gearbox and on the outer side near the gear tooth tip. The gear oil-air nozzles are disposed near the gear meshing part on the transmission gearbox. The bearing oil-air nozzles are disposed near each rolling bearing part. The gear oil-air nozzles and bearing oil-air nozzles are respectively connected to the oil-air lubrication system. The fan cooling system is disposed on the air intake. The top cooling nozzles are connected to the compressed air system through pipes.

[0006] In a further preferred embodiment of the above scheme, the gear oil-gas nozzle is located on the gear meshing side and / or near the meshing part of the gearbox.

[0007] In a further preferred embodiment of the above scheme, an oil-gas separator is installed on the exhaust side of the fan cooling system. This oil-gas separator is used to separate and recover the lubricating oil contained in the exhaust gas.

[0008] A further preferred embodiment of the above scheme is that air inlet filters are installed on both the horizontal air inlet and the side air inlet.

[0009] In a further preferred embodiment of the above scheme, the horizontal air inlet and the side air inlet are located on the upper part, lower part, or side of the transmission gearbox, and the number of the horizontal air inlet and the side air inlet is one or more; the air intake is located on the upper part, lower part, or side of the transmission gearbox, and the number of the air intake is one or more.

[0010] In a further preferred embodiment of the above scheme, the number of end-face cooling nozzles is one or more, wherein the plurality of end-face cooling nozzles are arranged in a circumferential position along both sides of the gear end face and close to the tooth root, and the end-face cooling nozzles are connected to a compressed air system through pipes.

[0011] In a further preferred embodiment of the above scheme, end-face cooling nozzles are provided on both sides of the gear in the transmission gearbox, and the end-face cooling nozzles are connected to the compressed air system.

[0012] According to another aspect of the present invention, an oil-air lubrication cooling method for a gear transmission device using the present invention includes the following steps:

[0013] The oil-air lubrication system provides an oil-air mixture to the gear oil-air nozzle and the bearing oil-air nozzle respectively. The gear oil-air nozzle sprays the oil-air mixture provided by the oil-air lubrication system onto the gear tooth surface to lubricate and cool the gear. The bearing oil-air nozzle sprays the oil-air mixture provided by the oil-air lubrication system onto each rolling bearing.

[0014] A compressed air system is used to supply cooling air to the end face cooling nozzle and the top cooling nozzle respectively. The end face cooling nozzle and the top cooling nozzle spray the cooling air onto the gear to dissipate heat and cool the gear teeth.

[0015] The fan cooling system draws in hot air containing oil and gas from the transmission gearbox through the air intake to cool the gears and creates a negative pressure environment inside the gearbox. The hot air containing oil and gas is then separated and recovered by an oil-gas separator.

[0016] In a further preferred embodiment of the above scheme, the amount of lubricating oil Q injected by the gear oil-gas nozzle 5 onto the gear tooth surface is... g The relationship between the minimum oil film thickness and the minimum oil film thickness satisfies:

[0017]

[0018] The rolling bearing is a cylindrical roller bearing, and the bearing oil-air nozzle injects a minimum amount Q of lubricating oil mixture onto each cylindrical roller bearing. r The relationship between the minimum oil film thickness and the minimum oil film thickness satisfies:

[0019]

[0020] Among them, f e f is the effective utilization coefficient of lubricating oil. s Where n is the safety factor for lubricating oil quantity, z is the rotational speed of the gear or bearing, L is the involute arc length of the gear tooth surface, F is the tooth width of the gear, β is the helix angle of the gear, and h is the number of teeth on the gear. 1min and h 2min Here, v represents the minimum oil film thickness, v is the rolling linear velocity of the cylindrical roller bearing roller, and f is the minimum oil film thickness. r The coefficient representing the amount of oil required for the elastohydrodynamic oil film, k being the number of rollers in the rolling bearing, B being the roller width in the rolling bearing, and d being the coefficient representing the required amount of oil. irThis refers to the outer diameter of the inner ring of the rolling bearing.

[0021] In a further preferred embodiment of the above scheme, when the fan cooling system draws in a mixture of hot gas containing oil and gas from the transmission gearbox to cool the gears, the minimum flow rate Q of the drawn mixture of hot gas is... a satisfy:

[0022]

[0023] P in the formula M For gear transmission meshing losses, P W For the wind resistance loss of gear transmission, P B ξ represents the bearing power loss, ρ represents the effective utilization rate of cooling air, C represents the cooling air density, and ΔT represents the cooling air specific heat capacity.

[0024] In summary, the present invention adopts the above technical solution and has the following technical effects:

[0025] The oil-air lubrication cooling device for gear transmissions of this invention solves the problem that oil-air lubrication cannot be used in gear transmissions, especially closed gear transmissions. Based on the minimum oil film thickness for elastohydrodynamic lubrication, a quantitative calculation method for the required lubricating oil flow rate for oil-air lubrication of cylindrical roller bearings and gear meshing transmissions is proposed. This solves the problem of quantitatively calculating the lubricating oil flow rate when using oil-air lubrication in gear transmissions, greatly reducing the amount of lubricating oil required to ensure the operation of the gear transmission. It eliminates the power loss from churning and pumping / extrusion caused by traditional splash lubrication and oil spray lubrication, avoiding the problems of high heat generation and low operating efficiency in gear transmissions. Because the amount of lubricating oil used is greatly reduced, the operating and maintenance costs of the gear transmission are lowered. Based on the power loss of gears when using oil-air lubrication, a quantitative calculation method for the required air flow rate for cooling gear transmissions is proposed, solving the problem of quantitatively calculating the cooling air flow rate when using oil-air lubrication in gear transmissions. Attached Figure Description

[0026] Figure 1 This is an overall schematic diagram of an oil-air lubrication and cooling device for a gear transmission device according to the present invention;

[0027] Figure 2 This is a side view of an oil-air lubrication and cooling device for a gear transmission device according to the present invention;

[0028] In the attached diagram, 1 is the oil-gas lubrication system, 2 is the fan cooling system, 3 is the oil-gas separator, 4 is the compressed air system, 5 is the gear oil-gas nozzle, 6 is the bearing oil-gas nozzle, 7 is the transmission gearbox, 8 is the horizontal air inlet, 9 is the side air inlet, 10 is the air inlet filter, 11 is the air intake, 12 is the end face cooling nozzle, and 13 is the top cooling nozzle. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments. However, it should be noted that many details listed in the specification are merely to provide the reader with a thorough understanding of one or more aspects of the present invention, and these aspects of the invention can be implemented even without these specific details.

[0030] Combination Figure 1 , Figure 2 As shown, according to the present invention, an oil-air lubrication and cooling device for a gear transmission device includes an oil-air lubrication system 1, a fan cooling system 2, a compressed air system 4, and gear oil-air nozzles 5 and bearing oil-air nozzles 6 disposed on a transmission gearbox 7. The device is characterized in that: a horizontal air inlet 8 and a side air inlet 9 for purifying and drawing in cooling air are respectively disposed on both sides of the transmission gearbox 7, the horizontal air inlet 8 and the side air inlet 9 being disposed on the upper part, lower part, or side of the transmission gearbox 7, and the number of horizontal air inlets 8 and side air inlets 9 being one or more; an air intake 11 is disposed on the upper part, lower part, or side of the transmission gearbox 7, and the number of air intake 11 is one or more; an air intake 11 for drawing in oil and air is disposed at the top of the transmission gearbox 7; end-face cooling nozzles 12 are disposed on both sides of the gear end faces inside the transmission gearbox 7; and the gear oil-air nozzles 5 are disposed on the transmission gearbox 7 near the gear meshing parts. The transmission gearbox 7 is located near the gear meshing side and / or the meshing disengagement area. The bearing oil-air nozzle 6 is located near each rolling bearing. The gear oil-air nozzle 5 and the bearing oil-air nozzle 6 are respectively connected to the oil-air lubrication system 1. The fan cooling system 2 is installed on the air intake 11. The end face cooling nozzle 12 is connected to the compressed air system 4. Air intake filters 10 are installed on both the horizontal air intake 8 and the side air intake 9 to purify the cooling air drawn into the gear transmission device. This invention uses the oil-air lubrication system 1 to lubricate and cool the meshing gears and supporting bearings, which greatly reduces the amount of lubricating oil required to ensure the operation of the gear transmission device. It eliminates the oil stirring power loss and pumping and squeezing power loss caused by the use of traditional splash lubrication and oil spray lubrication in the gear transmission device, and avoids the problems of high heat generation and low operating efficiency of the gear transmission device. Because the amount of lubricating oil used is greatly reduced, the operation and maintenance costs of the gear transmission device are reduced.

[0031] In some inventions, combined with Figure 1 , Figure 2As shown, an oil-gas separator 3 is installed on the exhaust side of the fan cooling system 2. The oil-gas separator 3 is used to separate and recover the lubricating oil contained in the exhaust gas. The fan cooling system 2 (suction fan) draws hot air containing oil and gas mixture from the transmission gearbox 7 of the gear transmission device. While cooling the gear transmission device, the transmission gearbox 7 is evacuated to a negative pressure environment, which reduces the agitation and friction between the rotating parts and the oil-gas mixture, reduces the wind resistance loss of the rotating parts, and improves the operating efficiency of the gear transmission device. All the hot air containing oil and gas is drawn in and passes through the oil-gas separator 3, where the lubricating oil contained in it is separated and recovered, avoiding the leakage of lubricating oil and oil-gas, thereby further avoiding environmental pollution.

[0032] In this invention, combined with Figure 1 , Figure 2 As shown, the number of end-face cooling nozzles 12 is one or more, wherein multiple end-face cooling nozzles 12 are arranged and distributed along the circumference of both end faces of the gear and near the tooth root. The end-face cooling nozzles 12 are connected to the compressed air system 4 through pipes. In this invention, one or more top cooling nozzles 13 are provided inside the transmission gearbox 7 and near the outer side of the gear tooth tip. The top cooling nozzles 13 are connected to the compressed air system 4 through pipes. In order to cool the gear more effectively, the present invention configures the compressed air system 4 as needed, and arranges end-face cooling nozzles at the position near the tooth root on both end faces of the gear. The cooling air provided by the compressed air system 4 is delivered to the end-face cooling nozzles 12 through pipes and then sprayed onto both end faces of the gear to dissipate heat and cool the gear. The end-face cooling nozzles 12 can be arranged in one or more side by side and multiple locations are arranged along the circumference near the tooth root of the gear, and the number of end-face cooling nozzles can be changed. In this invention, according to the cooling requirements, a top cooling nozzle 13 is also provided on the outer side of the gear near the tooth tip. The cooling air provided by the compressed air system 4 is delivered to the top cooling nozzle through the pipe and then sprayed onto the teeth of the gear to dissipate heat and cool the gear. Moreover, the number of top cooling nozzles can also be changed.

[0033] According to another aspect of the invention, in combination Figure 1 , Figure 2As shown, an oil-air lubrication and cooling method for a gear transmission device according to the present invention includes the following steps: First, an oil-air lubrication system 1 provides an oil-air mixture to the gear oil-air nozzle 5 and the bearing oil-air nozzle 6 respectively. The gear oil-air nozzle 5 sprays the oil-air mixture provided by the oil-air lubrication system 1 onto the gear tooth surface to lubricate and cool the gear. The bearing oil-air nozzle 6 sprays the oil-air mixture provided by the oil-air lubrication system 1 onto each rolling bearing. By using the oil-air lubrication system 1 and the gear oil-air nozzle 5 and the bearing oil-air nozzle 6 to lubricate and cool the meshing gears and the supporting bearings respectively, the amount of lubricating oil required to ensure the operation of the gear transmission device is greatly reduced, eliminating the need for traditional splash lubrication and spray lubrication in gear transmission devices. The power loss from churning and pumping / extrusion during lubrication is avoided, thus preventing the high heat generation and low operating efficiency of the gear transmission device. The amount of lubricating oil used is greatly reduced, thereby lowering the operating and maintenance costs of the gear transmission device. Secondly, the compressed air system 4 provides cooling air to the end face cooling nozzle 12 and the top cooling nozzle 13, respectively, which spray the cooling air onto the gears for heat dissipation and cooling. Finally, the fan cooling system 2 draws in the oil-gas mixture from the transmission gearbox 7 through the air intake 11 to cool the gears and creates a negative pressure environment inside the gearbox 7. The oil-gas mixture is then separated and recovered by the oil-gas separator 3.

[0034] In this invention, based on the minimum oil film thickness for elastohydrodynamic lubrication, when the gear oil-air nozzle 5 injects the oil-air mixture onto the gear tooth surface, there exists a minimum oil film thickness h. 1min The minimum amount of lubricating oil Q injected by gear oil nozzle 5 g (m 3 / s) Minimum oil film thickness h required for gear meshing transmission 1min It can be obtained from the following formula:

[0035]

[0036] The oil film thickness h required for gear meshing transmission can be obtained from the above formula. 1min The amount of lubricating oil Q injected by gear oil nozzle 5 g The relationship between them;

[0037] If the object being lubricated and cooled by the bearing oil-air nozzle 6 is a cylindrical roller bearing, then the theoretical minimum amount of lubricating oil Q required to be injected by the bearing oil-air nozzle 6 for each cylindrical roller bearing is... r (m 3 The value of / s can be obtained from the following formula.

[0038]

[0039] The required oil film thickness h for each rolling bearing can be obtained from the above formula. 2min The amount of lubricating oil Q injected by the bearing oil-gas nozzle 6 r The relationship between them;

[0040] The minimum airflow rate required for suction cooling of the gear transmission is the cooling airflow rate Q drawn by the fan cooling system 2. a The formula (L / min) yields:

[0041]

[0042] The required cooling airflow Q from the fan cooling system 2, which is used to cool the gear transmission, can be obtained using the above formula. a (L / min). This gives the required cooling air suction flow rate Q for gear transmission cooling. a (L / min), where f e f is the effective utilization coefficient of lubricating oil. s Here, n is the safety factor for the amount of lubricating oil, z is the rotational speed of the gear or bearing (r / min), L is the involute arc length of the gear tooth surface (m), F is the tooth width of the gear (m), β is the helix angle of the gear (°), and h is the number of teeth on the gear. 1min and h 2min Let v be the minimum oil film thickness (m) based on line contact elastohydrodynamic lubrication, v be the rolling linear velocity of the cylindrical roller bearing roller (m / s), and f be the minimum oil film thickness (m). r To account for the coefficient of oil quantity required for the formation of an elastohydrodynamic oil film between the rollers, cage, and flanges, k is the number of rollers in the cylindrical roller bearing, B is the roller width of the cylindrical roller bearing, and d... ir P is the outer diameter (m) of the inner ring of the cylindrical roller bearing. M P is the gear transmission meshing loss (kW). W P is the wind resistance loss of gear transmission (kW). B Let ξ be the bearing power loss (kW), ξ be the effective utilization rate of cooling air, and ρ be the density of cooling air (kg / m³). 3 C is the specific heat capacity of the cooling air (J / (kg·℃)), and ΔT is the temperature rise of the cooling air (℃).

[0043] Based on the minimum oil film thickness of elastohydrodynamic lubrication, this invention proposes a quantitative calculation method for the lubricating oil flow rate required for oil-air lubrication in cylindrical roller bearings and gear meshing transmissions, solving the problem of not being able to quantitatively calculate the lubricating oil flow rate when using oil-air lubrication in gear transmission devices. Based on the power loss of gears when using oil-air lubrication, this invention also proposes a quantitative calculation method for the air flow rate required to cool gear transmission devices, solving the problem of not being able to quantitatively calculate the cooling air flow rate when using oil-air lubrication in gear transmission devices.

[0044] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A cooling method for an oil-air lubrication cooling device for a gear transmission device, the oil-air lubrication cooling device comprising an oil-air lubrication system, a fan cooling system, a compressed air system, and gear oil-air nozzles and bearing oil-air nozzles disposed on a transmission gearbox, characterized in that: A horizontal air inlet and a side air inlet are respectively provided on both sides of the transmission gearbox for purifying the intake cooling air. An air intake for drawing in oil and gas is provided at the top of the transmission gearbox. One or more top cooling nozzles are provided inside the transmission gearbox and on the outer side near the gear tooth tip. The gear oil and gas nozzles are provided near the gear meshing part on the transmission gearbox. The bearing oil and gas nozzles are provided near each rolling bearing part. The gear oil and gas nozzles and the bearing oil and gas nozzles are respectively connected to the oil and gas lubrication system. The fan cooling system is provided on the air intake. The top cooling nozzles are connected to the compressed air system through pipes. An oil-gas separator is installed on the exhaust side of the fan cooling system. This oil-gas separator is used to separate and recover the lubricating oil contained in the exhaust gas. An air inlet filter is installed on both the horizontal air inlet and the side air inlet. The horizontal air inlet and the side air inlet are located on the upper, lower, or side of the transmission gearbox, and there are one or more horizontal air inlets and one or more side air inlets. The suction port is located on the upper, lower, or side of the transmission gearbox, and there are one or more suction ports. The cooling method includes the following steps: The oil-air lubrication system provides an oil-air mixture to the gear oil-air nozzle and the bearing oil-air nozzle respectively. The gear oil-air nozzle sprays the oil-air mixture provided by the oil-air lubrication system onto the gear tooth surface to lubricate and cool the gear. The bearing oil-air nozzle sprays the oil-air mixture provided by the oil-air lubrication system onto each rolling bearing. A compressed air system is used to supply cooling air to the end face cooling nozzle and the top cooling nozzle respectively. The end face cooling nozzle and the top cooling nozzle spray the cooling air onto the gear to dissipate heat and cool the gear. The fan cooling system draws in hot air containing oil and gas from the transmission gearbox through the air intake to cool the gears and creates a negative pressure environment inside the gearbox. The hot air containing oil and gas is then separated and recovered by an oil-gas separator. The gear oil-gas nozzle injects an oil-gas mixture onto the gear tooth surface as lubricating oil. Q g The relationship between the minimum oil film thickness and the minimum oil film thickness satisfies: ； The rolling bearing is a cylindrical roller bearing, and the bearing oil-air nozzle injects a minimum amount of lubricating oil mixture onto each cylindrical roller bearing. Q r The relationship between the minimum oil film thickness and the minimum oil film thickness satisfies: ； in, f e The effective utilization coefficient of lubricating oil. f s To account for the safety factor of the lubricating oil quantity, n The rotational speed of the gear or bearing. z This refers to the number of teeth on the gear. L Let be the arc length of the involute curve on the tooth surface of the gear. F The tooth width of the gear. β The helix angle of the gear. h 1min and h 2min These are the minimum oil film thicknesses, v This refers to the rolling linear velocity of the rollers in a cylindrical roller bearing. f r This is a coefficient representing the amount of oil required for the elastohydrodynamic oil film. k This refers to the number of rollers in a cylindrical roller bearing. B This refers to the roller width of the cylindrical roller bearing. d ir This refers to the outer diameter of the inner ring of the cylindrical roller bearing.

2. The cooling method of the oil-air lubrication cooling device for gear transmission according to claim 1, characterized in that: The gear oil and gas nozzle is located on the gear meshing side and / or near the meshing part of the gearbox.

3. The cooling method of the oil-air lubrication cooling device for gear transmission according to claim 1, characterized in that: End face cooling nozzles are provided on both sides of the gear in the transmission gearbox, and the end face cooling nozzles are connected to the compressed air system.

4. The cooling method of the oil-air lubrication cooling device for gear transmission according to claim 3, characterized in that: The number of the end face cooling nozzles is one or more, wherein the plurality of the end face cooling nozzles are arranged in a circumferential position along both sides of the gear end face and close to the tooth root, and each end face cooling nozzle is connected to the compressed air system through a pipe.

5. A cooling method for an oil-air lubrication cooling device for a gear transmission device according to claim 1, characterized in that: When the fan cooling system draws in a mixture of hot air containing oil and gas from the transmission gearbox to cool the gears, the minimum flow rate of the drawn mixture of hot air is... Q a satisfy: ； In the formula P M For gear transmission meshing losses, P W This is due to wind resistance loss in gear transmission. P B For bearing power loss, ξ To improve the effective utilization rate of cooling air, ρ To cool the air density, C For the specific heat capacity of cooling air, Δ T To cool the air temperature rise.

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