Lubricating structure of gear box of large-tonnage automobile crane
By installing self-priming oil pumps on the first and second shafts and combining them with coolers, the problem of reduced self-priming capability of the lubricating oil pumps in the transfer case gearbox under high loads was solved, achieving continuous and effective lubrication, extending the service life of gears and bearings, and reducing noise.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHUZHOU GEAR CO LTD
- Filing Date
- 2025-05-30
- Publication Date
- 2026-05-26
AI Technical Summary
The existing transfer case gearboxes for ultra-large tonnage truck cranes suffer from reduced self-priming capability of the lubricating oil pump under high loads and when climbing slopes, leading to lubrication failure. The oil temperature is high and cannot be dissipated in time, affecting the wear and noise of gears and bearings, resulting in poor adaptability to working conditions and shortened service life.
Self-priming oil pump one and self-priming oil pump two are installed on the first shaft and the second shaft respectively, and are connected to the cooler through oil pipes. Self-priming oil pump one rotates synchronously with the first shaft, and self-priming oil pump two rotates synchronously with the second shaft to ensure that the lubrication capacity remains unchanged. The cooler reduces the oil temperature to achieve continuous and effective lubrication.
It improves the adaptability of the lubrication system to different operating conditions, extends the fatigue life of gears and bearings, reduces the aging rate of lubricating oil, and reduces vibration and noise.
Smart Images
Figure CN224283409U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a lubrication structure for a transfer case gearbox of a large-tonnage truck crane, used for lubrication of the transfer case gearbox. Background Technology
[0002] Transfer case gearbox for truck cranes, such as Figure 1 As shown, the system includes a housing 100, a first shaft 101, a second shaft 102, a third shaft 103, and a planetary differential 104 mounted on the housing 100 and arranged in parallel from top to bottom. The output of the planetary differential 104 connects the front-wheel drive and rear-wheel drive of the vehicle. The planetary differential 104 is equipped with a gear sleeve-type differential lock 105. The first shaft 101 is equipped with a high-gear drive gear 1011, a low-gear drive gear 1012, and a shift sleeve 1013. The second shaft 102 is equipped with... The high-gear driven gear 1021 meshes with the high-gear driving gear 1012, and the low-gear driven gear 1022 meshes with the low-gear driving gear 1012. A constant mesh gear 1031 is mounted on the three shafts 103. The high-gear driven gear 1021 and the planetary carrier of the planetary differential 104 mesh with the constant mesh gear 1031 respectively. Existing transfer case gearboxes for ultra-large tonnage truck cranes generally have a lubricating oil pump installed on the second shaft to meet the lubrication requirements of the gearbox. The drawback of this design is:
[0003] 1. With the increase in tonnage and the application of wind power, ultra-large tonnage truck cranes often use the transfer case in low gear for driving and climbing. At this time, the second axle is decelerating. Especially when climbing, due to the weight of the vehicle, the overall speed cannot be increased. The second axle is also decelerated, which will reduce the self-priming ability of the lubricating oil pump on the second axle or even prevent it from drawing oil, thus causing the transfer case to lose its lubrication function.
[0004] 2. When the gearbox is running continuously, the oil inside cannot dissipate heat in time, resulting in a high oil temperature, reduced lubrication effect, and accelerated wear of gears and bearings.
[0005] The above two points result in poor adaptability of the transfer case gearbox to operating conditions, shorten the fatigue life of gears and bearings, accelerate the aging of lubricating oil, and increase vibration and noise during gearbox operation. Utility Model Content
[0006] The lubrication structure of the transfer case gearbox for large-tonnage truck cranes provided by this utility model ensures that when the transfer case is in low gear or climbing a slope, causing the self-priming capacity of the second self-priming oil pump to decrease, the self-priming capacity of the first self-priming oil pump remains unchanged. This guarantees effective lubrication of the gearbox, reduces wear on gears and bearings caused by untimely lubrication, lowers the probability of lubrication failure under extreme operating conditions, ensures the lubrication effect of the oil on gears and bearings during long-term continuous operation of the gearbox, improves the adaptability of the lubrication system to operating conditions, extends the fatigue life of gears and bearings in the gearbox, reduces the aging rate of the lubricating oil, and reduces vibration and noise during gearbox operation.
[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0008] A lubrication structure for a transfer case gearbox of a large-tonnage truck crane includes a housing and a self-priming oil pump assembly that pumps oil from the bottom of the housing upwards to lubricate the gears and bearings inside the housing. The self-priming oil pump assembly comprises a first self-priming oil pump mounted on a shaft within the housing, a second self-priming oil pump mounted on a second shaft within the housing, and a cooler connected to the oil outlet of the second self-priming oil pump via an oil pipe. The oil inlets of the first and second self-priming oil pumps are respectively connected to the bottom of the housing via oil pipes. The oil outlet of the first self-priming oil pump is connected to an oil passage within the housing. The oil outlet of the cooler is connected to the housing via an oil pipe.
[0009] Preferably, a self-priming oil pump is installed at the rear end of a shaft, a second self-priming oil pump is installed at the front end of a shaft, and a cooler is installed on the front side of the housing.
[0010] Preferably, the oil pipe connected to the oil outlet of the cooler is equipped with an oil nozzle one for spraying oil onto the high-gear driven gear of the second shaft and an oil nozzle two for spraying oil onto the low-gear driven gear of the second shaft.
[0011] Preferably, the shaft is a hollow shaft with an oil passage along its central axis, and a radial oil injection hole is opened on the shaft to spray out the oil. The oil outlet of the self-priming oil pump is connected to the oil passage on the shaft.
[0012] Preferably, an oil collection groove is formed on the housing near the bearing mounting hole, and the oil collection groove is connected to the bearing mounting hole through an oil passage formed on the housing.
[0013] The beneficial effects of this utility model are:
[0014] This utility model discloses a lubrication structure for a transfer case gearbox in a large-tonnage truck crane. A self-priming oil pump is installed on one shaft, and a self-priming oil pump is installed on the other shaft. The first and second self-priming oil pumps rotate synchronously with the first and second shafts, respectively, pumping oil from the bottom of the housing upwards to lubricate the gears and bearings inside the housing. When the transfer case is in low gear or climbing a slope, causing a decrease in the self-priming capacity of the second self-priming oil pump, the rotational speed of the first shaft remains unaffected, and the self-priming capacity of the first self-priming oil pump remains unchanged, ensuring effective lubrication of the gearbox. This reduces wear on gears and bearings caused by untimely lubrication and lowers the probability of lubrication failure under extreme operating conditions. A cooler is connected to the oil outlet of the second self-priming oil pump. The oil drawn from the second self-priming oil pump is cooled by the cooler before being guided into the housing, further reducing the oil temperature and ensuring effective lubrication of gears and bearings during long-term continuous operation of the gearbox. This improves the adaptability of the lubrication system to various operating conditions, extends the fatigue life of gears and bearings inside the gearbox, reduces the aging rate of the lubricating oil, and decreases vibration and noise during gearbox operation. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the transmission structure of a transfer case gearbox for truck cranes in the prior art.
[0016] Figure 2 This is a schematic diagram of the lubrication structure of the transfer case gearbox for a large-tonnage truck crane according to this utility model. Detailed Implementation
[0017] The following is combined with Figure 2 The embodiments of this utility model will be described in detail below.
[0018] A lubrication structure for a transfer case gearbox of a large-tonnage truck crane includes a housing 100 and a self-priming oil pump assembly 1 that pumps oil from the bottom of the housing 100 upwards to lubricate the gears and bearings inside the housing. The self-priming oil pump assembly 1 includes a self-priming oil pump 2 mounted on a shaft 101 within the housing 100, a self-priming oil pump 3 mounted on a second shaft 102 within the housing 100, and a cooler 4 connected to the oil outlet of the self-priming oil pump 3 via an oil pipe. The oil inlets of the self-priming oil pump 2 and the self-priming oil pump 3 are respectively connected to the bottom of the housing 100 via oil pipes. The oil outlet of the self-priming oil pump 2 is connected to an oil passage A within the housing 100. The oil outlet of the cooler 4 is connected to the housing 100 via an oil pipe.
[0019] The lubrication structure of the transfer case gearbox for large-tonnage truck cranes described above includes a self-priming oil pump 2 installed on shaft 101 and a self-priming oil pump 3 installed on shaft 102. Self-priming oil pump 2 rotates synchronously with shaft 101, and self-priming oil pump 3 rotates synchronously with shaft 102, pumping oil from the bottom of the housing upwards to lubricate the gears and bearings inside the housing. When the transfer case is in low gear or climbing a slope, causing a decrease in the self-priming capacity of self-priming oil pump 3, the rotational speed of shaft 101 remains unaffected, and the self-priming capacity of self-priming oil pump 2 remains unchanged, ensuring proper lubrication of the gearbox. Effective lubrication reduces wear on gears and bearings caused by untimely lubrication, lowers the probability of lubrication failure under extreme operating conditions, and connects the oil outlet of the self-priming oil pump 2 3 to the cooler 4. The oil drawn from the self-priming oil pump 2 3 is cooled by the cooler 4 before being guided into the housing 100, reducing the oil temperature and ensuring the lubrication effect of the oil on the gears and bearings during the long-term continuous operation of the gearbox. This improves the adaptability of the lubrication system to operating conditions, extends the fatigue life of gears and bearings in the gearbox, reduces the aging rate of the lubricating oil, and reduces vibration and noise during gearbox operation.
[0020] The self-priming oil pump 2 is mounted at the rear end of shaft 101, the self-priming oil pump 3 is mounted at the front end of shaft 102, and the cooler 4 is mounted on the front side of the housing. The self-priming oil pump 2 is mounted at the rear end of shaft 101, located at the rear of housing 100, while the self-priming oil pump 3 is mounted at the front end of shaft 3, located at the front of housing 100. The oil pipe connecting to the self-priming oil pump 2 and leading to the bottom of the housing is positioned near the rear of the housing, while the oil pipe connecting to the self-priming oil pump 2 and leading to the bottom of the housing is positioned near the front of the housing. This design prevents both self-priming oil pumps from drawing oil from the same location at the bottom of the housing, thus improving the reliability of oil suction.
[0021] The cooler 4 is equipped with an oil nozzle 5 (spraying oil onto the high-gear driven gear 1021 of the second shaft 102) and an oil nozzle 6 (spraying oil onto the low-gear driven gear 1022 of the second shaft 102) connected to the oil outlet end. Since the gears and bearings on the planetary differential are close to the bottom of the housing, lubrication can be achieved through oil splashed from the gears. However, since the second shaft 102 and the first shaft 101 are located above the third shaft 103, the amount of oil splashed from the gears is limited. The oil from the cooler 4 is guided through the oil pipe to the oil nozzles 5 and 6 and sprayed upwards, effectively lubricating the gears on the second shaft. The sprayed oil drips down and also lubricates the gears on the third shaft, eventually falling back to the bottom of the housing.
[0022] The shaft 101 is a hollow shaft with an oil passage A along its central axis. Radial oil injection holes are also present on the shaft 101 to spray out oil. The oil outlet of the self-priming oil pump 2 is connected to the oil passage A on the shaft 101. The self-priming oil pump 2 pumps oil from the bottom of the housing into the oil passage A on the shaft 101, where it is sprayed out through the radial oil injection holes to lubricate the gears on the shaft. The oil also drips downwards to lubricate the gears and bearings below, eventually falling back to the bottom of the housing.
[0023] The housing 100 has an oil collection groove B located near the bearing mounting hole. The oil collection groove B is connected to the bearing mounting hole via an oil passage on the housing 100. The oil collection groove B can receive oil pumped upwards by self-priming oil pump 2 and self-priming oil pump 3 and then dripping downwards, as well as oil splashed out by gears. The received oil is then guided into the nearest bearing mounting hole to form active lubrication of the bearing and improve the reliability of bearing lubrication.
[0024] The technical solutions of the embodiments of this utility model have been fully described above with reference to the accompanying drawings. It should be noted that the described embodiments are only a part of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
Claims
1. A lubricating structure of a transfer gearbox for a large-tonnage mobile crane, comprising a housing and a self-suction oil pump assembly that pumps oil at the bottom of the housing upward to lubricate gears and bearings in the housing, characterized in that: The self-priming oil pump assembly includes a self-priming oil pump I mounted on a shaft in the housing, a self-priming oil pump II mounted on a second shaft in the housing, and a cooler connected to the oil outlet of the self-priming oil pump II via an oil pipe. The oil inlets of the self-priming oil pump I and the self-priming oil pump II are respectively connected to the bottom of the housing via oil pipes. The oil outlet of the self-priming oil pump I is connected to the oil passage inside the housing. The oil outlet of the cooler is connected to the housing via an oil pipe.
2. The lubricating structure of the transfer gearbox for large-tonnage mobile cranes according to claim 1, characterized in that: Self-priming oil pump one is installed at the rear end of shaft one, self-priming oil pump two is installed at the front end of shaft two, and cooler is installed on the front side of housing.
3. The lubrication structure of the transfer case gearbox for a large-tonnage truck crane according to claim 2, characterized in that: The oil pipe connected to the oil outlet of the cooler is equipped with an oil nozzle 1 that sprays oil onto the high-gear driven gear of the second shaft and an oil nozzle 2 that sprays oil onto the low-gear driven gear of the second shaft.
4. The lubrication structure of the transfer case gearbox for a large-tonnage truck crane according to claim 1, characterized in that: The shaft is a hollow shaft with an oil passage along its central axis, and a radial oil injection hole is opened on the shaft to spray out the oil. The oil outlet of the self-priming oil pump is connected to the oil passage on the shaft.
5. The lubrication structure of the transfer case gearbox for a large-tonnage truck crane according to claim 1, characterized in that: An oil collection groove is formed on the housing near the bearing mounting hole, and the oil collection groove is connected to the bearing mounting hole through an oil passage formed on the housing.