Coaxial speed reducer integrated structure

Abstract

The coaxial speed reducer integrated structure is installed in a speed reducer shell and comprises a planetary gear assembly and a differential mechanism, the planetary gear assembly comprises a sun gear connected with the output end of a driving motor, a planet carrier, an inner gear ring fixed to the speed reducer shell, and a planetary gear rotationally installed on the planet carrier and meshed with the sun gear and the inner gear ring. The differential mechanism comprises a lower half differential shell, a differential mechanism shaft, a bevel gear installed on the differential mechanism shaft and a half axle gear meshed with the bevel gear, the planet carrier comprises an upper installation plate and an upper half differential shell integrally formed under the upper installation plate, the planet gear is installed on the upper installation plate and extends out of the planet carrier, and the upper half differential shell and the lower half differential shell are in coaxial butt joint to form a differential shell. The bevel gear and the half axle gear are arranged in the differential shell, and the differential shaft extends out of the differential shell. The size and the weight of the planet carrier can be effectively reduced, casting forming is easier, the heat dissipation and lubricating efficiency of the planet gear assembly is improved, the dynamic balance of a transmission system is guaranteed, and the transmission reliability is improved.

Description

Technical Field

[0001] The utility model relates to a coaxial reducer integrated structure, belonging to the technical field of electric drive assembly of new energy vehicles. Background Art

[0002] The electric drive assembly of new energy vehicles includes motors, reducers and controllers. The integration technology of motors and controllers is mature, and the development of high-performance reducers is the main way to improve the overall success rate density, compactness and cost reduction of electric drives. The coaxial reducer integrates the planetary carrier of the reducer with the differential housing coaxially, and the input and output are arranged coaxially. Compared with the parallel shaft reducer, the structure is more compact and can effectively improve the torque density of the electric drive assembly. It is an important development trend of high-performance reducers in the future.

[0003] Most of the existing coaxial reducers integrate the planetary carrier and the differential housing, which makes casting difficult; most coaxial reducers rely on planetary gears for transmission, and there will be an obvious eccentric mass after the integration of the differential and the planetary carrier, which will cause dynamic balance problems in the transmission system; the coupling contact area of ​​the gears inside the differential is large, and the friction and temperature rise quickly during movement. The integrated planetary carrier and differential housing will quickly transfer heat to the planetary reduction structure during the heat dissipation of the differential housing. Improper cooling and lubrication will cause accelerated wear of the internal gears and shafts. Utility Model Content

[0004] The coaxial reducer integrated structure provided by the utility model can effectively reduce the volume and weight of the planetary carrier, is easier to cast, improves the heat dissipation and lubrication efficiency of the planetary gear assembly, reduces the wear rate, prolongs the service life, avoids the mass eccentricity of the coaxial reducer integrated structure, ensures the dynamic balance of the transmission system, and improves the transmission reliability.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] The coaxial reducer integrated structure is installed in the reducer housing, including a planetary gear assembly and a differential. The planetary gear assembly includes a sun gear connected to the output end of the drive motor, a planet carrier, an inner ring fixed to the reducer housing, and planetary gears rotatably installed on the planet carrier and respectively meshing with the sun gear and the inner ring. The differential includes a lower differential housing, a differential shaft, a bevel gear installed on the differential shaft, and a half-axle gear meshing with the bevel gear. It is characterized in that: the planet carrier includes an upper mounting plate, an upper half differential housing integrally formed directly below the upper mounting plate, the planetary gears are installed on the upper mounting plate and extend from the planet carrier, the upper half differential housing is coaxially connected with the lower half differential housing to form a differential housing, the bevel gear and the half-axle gears are arranged in the differential housing, and the differential shaft extends from the differential housing.

[0007] Preferably, a hollow structure is formed between the upper mounting plate and the upper half differential housing, and the planetary gears extend out of the hollow structure.

[0008] Preferably, the planetary gear is a double gear, including an upper gear, a lower gear with a smaller diameter than the upper gear, and a planetary gear shaft connecting the upper gear and the lower gear shaft, the upper gear is meshed with the sun gear, the lower gear is meshed with the inner ring gear, and the planetary gear shaft is rotatably mounted on the upper mounting plate.

[0009] Preferably, the number of the planetary gears is three, the lower gear extends out of the planet carrier and meshes with the inner gear ring, the upper gear is evenly distributed on the outer periphery of the sun gear and extends out of the planet carrier, the number of the bevel gears is three, the differential shaft includes a circular ring and an extending shaft extending radially along the circular ring, the number of the extending shafts is three, each extending shaft is equipped with a bevel gear, and the extending shafts extend from the differential housing respectively.

[0010] Preferably, an upper semicircular hole is formed at the bottom of the upper semi-differential shell, and a lower semicircular hole corresponding to the upper semicircular hole is formed at the top of the lower semi-differential shell. The upper semicircular hole and the lower semicircular hole are assembled into a circular hole as the upper semi-differential shell and the lower semi-differential shell are connected, and the extended shaft extends out of the circular hole.

[0011] Preferably, it also includes an oil collecting ring coaxially arranged on the outer periphery of the sun gear, a snap hole is opened on the upper mounting plate, and the oil collecting ring has a snap corresponding to the snap hole, and the snap is snapped into the snap hole to install the oil collecting ring on the upper mounting plate.

[0012] The beneficial effects of the utility model are:

[0013] The utility model discloses a coaxial reducer integrated structure, the planetary carrier comprises an upper mounting plate and an upper differential shell, the upper differential shell and the lower differential shell are coaxially connected to form a differential shell, compared with the integrated structure of the planetary carrier and the differential shell, the volume and weight of the planetary carrier can be effectively reduced, and it is easier to cast, the upper differential shell is integrally formed just below the upper mounting plate, when the differential is running, the space between the upper mounting plate and the upper differential shell is used for heat dissipation and for the internal and external circulation of lubricating oil, thereby improving the heat dissipation and lubrication efficiency of the planetary gear assembly, reducing the wear rate and extending the service life.

[0014] The planet carrier and the lower differential housing are split structures. The mass of the planet carrier and the lower differential housing can be adjusted according to the number of planetary gears in the planetary reduction assembly to avoid mass eccentricity of the coaxial reducer integrated structure, ensure the dynamic balance of the transmission system, and improve transmission reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a cross-sectional view of the coaxial reducer integrated structure in a specific implementation manner.

[0016] Figure 2 This is a schematic diagram of the exploded view of the integrated structure of the coaxial reducer.

[0017] Figure 3Schematic diagram of the differential shaft.

[0018] Figure 4 Schematic diagram of the oil collecting ring snapped onto the upper mounting plate. DETAILED DESCRIPTION

[0019] Combine the following Figures 1 to 4 The embodiments of the utility model are described in detail.

[0020] The coaxial reducer integrated structure is installed in the reducer housing, including a planetary gear assembly 1 and a differential 2. The planetary gear assembly 1 includes a sun gear 3 connected to the output end of the drive motor, a planet carrier 4, an inner ring gear 5 fixed to the reducer housing, and a planetary gear 6 rotatably mounted on the planet carrier 4 and meshing with the sun gear 3 and the inner ring gear 5 respectively. The differential 2 includes a lower half differential case 7, a differential shaft 8, a bevel gear 9 mounted on the differential shaft 8, and a half-axle gear 10 meshing with the bevel gear 9. It is characterized in that: the planet carrier 4 includes an upper mounting plate 11, an upper half differential case 12 integrally formed directly below the upper mounting plate 11, the planetary gear 6 is mounted on the upper mounting plate 11 and extends from the planet carrier 4, the upper half differential case 12 is coaxially connected with the lower half differential case 7 to form a differential case, the bevel gear 9 and the half-axle gear 10 are arranged in the differential case, and the differential shaft 8 extends from the differential case.

[0021] The above-mentioned coaxial reducer integrated structure, when running, the driving motor inputs power to the sun gear 3, the sun gear 3 drives the planetary gear 6 to rotate on the inner ring 5, thereby driving the planetary carrier 4 to rotate, the planetary carrier 4 drives the lower differential shell 7 to rotate, forming an upper differential shell 12 and a lower differential shell 7 connected to form a differential shell to rotate, so as to rotate the bevel gear 9, and the bevel gear 9 drives the half-shaft gear 10 to rotate, so as to realize the output of power, the planetary carrier 4 includes an upper mounting plate 11 and an upper differential shell 12, the upper differential shell 12 and the lower differential shell 7 are coaxially connected to form a differential shell, compared with the integrated structure of the planetary carrier and the differential shell, the volume and weight of the planetary carrier can be effectively reduced, and it is easier to cast, the upper differential shell 12 is integrally formed just below the upper mounting plate 11, and the space between the upper mounting plate 11 and the upper differential shell 12 is used for heat dissipation and for the internal and external circulation of lubricating oil when the differential is running, thereby improving the heat dissipation and lubrication efficiency of the planetary gear assembly 1, reducing the wear rate, and extending the service life. The planet carrier and the lower differential housing are separate structures. The masses of the planet carrier 4 and the lower differential housing 7 can be adjusted according to the number of planetary gears in the planetary reduction assembly to avoid mass eccentricity of the coaxial reducer integrated structure, ensure the dynamic balance of the transmission system, and improve transmission reliability.

[0022] There is a hollow structure 13 between the upper mounting plate 4 and the upper differential housing 12, and the planetary gear 6 extends from the hollow structure 13. The hollow structure 13 is used for heat dissipation and for the lubricating oil in the reducer housing to flow inside and outside the planetary gear assembly 1, thereby improving the heat dissipation and lubrication efficiency. The mass of the planetary carrier 4 can also be adjusted by the hollowing ratio of the hollow structure 13 to avoid mass eccentricity of the coaxial reducer integrated structure. In order to ensure timely lubrication and heat dissipation of the differential 2, oil circulation holes can be opened on the upper differential housing 12 and the lower differential housing 7 to allow the lubricating oil in the reducer housing to circulate in the differential housing.

[0023] The planetary gear 6 is a double gear, including an upper gear 61, a lower gear 62 having a smaller diameter than the upper gear 61, and a planetary gear shaft 63 connecting the upper gear 61 and the lower gear shaft 62. The upper gear 61 is meshed with the sun gear 3, the lower gear 62 is meshed with the inner gear ring 5, and the planetary gear shaft 63 is rotatably mounted on the upper mounting plate 11. The double gear 6 can effectively improve the reduction ratio and ensure the torque transmission efficiency.

[0024] Among them, the number of the planetary gears 6 is three, the lower gear 62 extends out of the planetary carrier 4 and meshes with the inner gear ring 5, the upper gear 61 is evenly distributed on the outer periphery of the sun gear 3 and extends out of the planetary carrier 4, the number of the bevel gears 9 is three, the differential shaft 8 includes a ring 81 and an extended shaft 82 extending radially along the ring, the number of the extended shafts 82 is three, each extended shaft 82 is equipped with a bevel gear 9, and the extended shafts 82 extend from the differential housing respectively. The three planetary gears 6 rotate on the inner gear ring 5 with the rotation of the sun gear 3 to drive the planetary carrier 4 to rotate, ensuring the reliability of torque transmission in the planetary gear assembly 1, the extended shaft 82 rotates synchronously with the planetary carrier 4, driving the three bevel gears 9 to rotate synchronously, so as to drive the two half-shaft gears 10 to rotate, ensuring the reliability of torque transmission in the differential 2, so that the torque transmission reliability of the coaxial reducer integrated structure is high.

[0025] The upper half differential housing 12 has an upper semicircular hole A at the bottom, and the lower half differential housing 7 has a lower semicircular hole B corresponding to the upper semicircular hole A at the top. The upper semicircular hole A and the lower semicircular hole B are joined together to form a circular hole, and the extension shaft 82 extends out of the circular hole. The upper semi-differential housing 12 and the lower semi-differential housing 7 are joined together by bolts, and the extension shaft 82 extends out of the circular hole formed by the upper semicircular hole A and the lower semicircular hole B, and rotates synchronously with the planet carrier 4, thereby driving the bevel gear 9 to rotate.

[0026] The oil collecting ring 14 is coaxially arranged on the outer periphery of the sun gear 3. The upper mounting plate 11 is provided with a buckle hole 111. The oil collecting ring 14 has a buckle 141 corresponding to the buckle hole 111. The buckle 141 is inserted into the buckle hole 111 to mount the oil collecting ring 14 on the upper mounting plate 11. The oil collecting ring 14 is buckled on the upper mounting plate 11, and the assembly and disassembly are convenient and simple. The lubricating oil flowing out from the output end of the driving motor flows into the oil collecting ring 14, and flows into the planetary gear assembly 1 and the differential 2 along the planet carrier 4, further improving the lubrication and heat dissipation effect of the integrated structure of the coaxial reducer.

[0027] The above is a complete description of the technical solutions of the embodiments of the utility model in combination with the accompanying drawings. It should be noted that the described embodiments are only part of the embodiments of the utility model. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

Claims

1. A coaxial reducer integrated structure, installed in a reducer housing, includes a planetary gear assembly and a differential, wherein the planetary gear assembly includes a sun gear connected to the output end of the drive motor, a planet carrier, an inner gear ring fixed to the reducer housing, and planetary gears rotatably mounted on the planet carrier and meshing with the sun gear and the inner gear ring respectively; the differential includes a lower half differential case, a differential shaft, a bevel gear mounted on the differential shaft, and a half-axle gear meshing with the bevel gear, characterized in that: The planetary carrier includes an upper mounting plate and an upper differential housing integrally formed directly below the upper mounting plate. The planetary gears are mounted on the upper mounting plate and extend from the planetary carrier. The upper differential housing is coaxially connected with the lower differential housing to form a differential housing. The bevel gear and the half-axle gear are arranged in the differential housing, and the differential shaft extends from the differential housing.

2. The coaxial reducer integrated structure according to claim 1 is characterized in that: A hollow structure is formed between the upper mounting plate and the upper half differential housing, and the planetary gears extend out of the hollow structure.

3. The coaxial reducer integrated structure according to claim 1 is characterized in that: The planetary gear is a double gear, including an upper gear, a lower gear with a smaller diameter than the upper gear, and a planetary gear shaft connecting the upper gear and the lower gear shaft. The upper gear is meshed with the sun gear, and the lower gear is meshed with the inner gear ring. The planetary gear shaft is rotatably mounted on the upper mounting plate.

4. The coaxial reducer integrated structure according to claim 3 is characterized in that: The number of the planetary gears is three, the lower gear extends out of the planet carrier and meshes with the inner gear ring, the upper gear is evenly distributed on the outer periphery of the sun gear and extends out of the planet carrier, the number of the bevel gears is three, the differential shaft includes a circular ring and an extended shaft extending radially along the circular ring, the number of the extended shafts is three, each extended shaft is equipped with a bevel gear, and the extended shafts extend from the differential housing respectively.

5. The coaxial reducer integrated structure according to claim 4 is characterized in that: An upper semicircular hole is formed at the bottom of the upper semi-difference shell, and a lower semicircular hole corresponding to the upper semicircular hole is formed at the top of the lower semi-difference shell. The upper semicircular hole and the lower semicircular hole are assembled into a circular hole when the upper semi-difference shell and the lower semi-difference shell are connected, and the extension shaft extends out of the circular hole.

6. The coaxial reducer integrated structure according to claim 1 is characterized in that: It also includes an oil collecting ring coaxially arranged on the outer periphery of the sun gear. A buckle hole is opened on the upper mounting plate. The oil collecting ring is provided with a buckle corresponding to the buckle hole. The buckle is inserted into the buckle hole to install the oil collecting ring on the upper mounting plate.

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