Commercial vehicle integrated axle with variable speed function and energy recovery device
By using planetary reducers and energy recovery devices in commercial vehicle axles, the problems of commercial vehicles being unable to provide large reduction ratios and brake failure have been solved, thus improving safety and economy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HEFEI UNIV OF TECH
- Filing Date
- 2023-06-20
- Publication Date
- 2026-07-21
AI Technical Summary
Existing commercial vehicle axles have problems such as not being able to provide a large reduction ratio, having a complex structure and being inconvenient to maintain, and frequent braking during steep descents leading to brake failure and energy waste.
It adopts a planetary reducer and a multi-gear design, with the reducer placed before the differential. Combined with an energy recovery device, it achieves a large reduction ratio through the planetary reducer and recovers energy during braking to reduce brake heat.
It achieves a large reduction ratio, reduces brake heat, improves vehicle safety and economy when descending steep slopes, and reduces maintenance costs.
Smart Images
Figure CN116653588B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of integrated axles for commercial vehicles, specifically relating to an integrated axle for commercial vehicles with a transmission function and an energy recovery device. Background Technology
[0002] Commercial vehicles refer to heavy-duty trucks. Commercial vehicle axles are mounted on the chassis, with wheels installed at both ends. The axles bear the load of the vehicle and maintain its normal operation on the road. Integrated axles, based on ordinary vehicles, add a reducer. The main function of the reducer is to reduce the speed of the vehicle's main shaft and increase torque. Regarding the axle structure of commercial vehicles, the torque transmission scheme in the axle is typically: the input torque passes through a single-stage gear reducer, differential, and half-shafts, finally reaching the wheels. This scheme uses a single-stage gear reducer to reduce speed before the torque is input to the differential, but due to space limitations, a large reduction ratio cannot be achieved. Regarding the braking performance of commercial vehicles, there are safety hazards in steep descent situations. When descending a steep slope, the driver needs to brake frequently to avoid excessive speed. However, frequent braking generates a large amount of heat in the braking components, accelerating wear and reducing their lifespan, and also increasing the risk of brake failure. Because commercial vehicles are heavy, the braking heat generated during braking is higher than that of ordinary vehicles, thus increasing the risk of brake failure. Furthermore, accelerating back to cruising speed after braking consumes more fuel.
[0003] CN114838104A discloses a reducer assembly and an automobile axle, which includes a driving bevel gear with a guide bearing and a driven bevel gear with a guide post and an annular groove. The mounting part of the bearing housing extends into the annular groove. This solution fits the guide bearing into the guide post, and the driving bevel gear is guided by the guide bearing, which effectively solves the problem of insufficient space for guide bearing arrangement and improves the transmission reliability of the driving bevel gear. However, this method uses a single-stage gear transmission, and the reduction ratio is relatively small, which is difficult to meet the high torque requirements of commercial vehicles.
[0004] CN115833653A discloses a vehicle energy recovery device and method. This method measures the temperature of the brake pads during braking and compares it to a preset target temperature. Based on the comparison result, it controls the switching of a thermoelectric conversion element on the outer surface of the brake pads. When the switch is on, heat energy is converted into electrical energy and stored in a battery. While this method recovers energy into the battery through a thermoelectric conversion element, its conversion efficiency is low, and it does not reduce brake pad wear, increasing operating costs.
[0005] Most existing axles have the following design problems: the power transmission scheme is mostly a single-stage gear reduction before the torque input differential, which has the disadvantages of not being able to provide a large reduction ratio, complex structure and inconvenient maintenance; the problem of frequent braking and brake failure caused by steep descent has not been structurally designed to solve; and the energy wasted during braking of commercial vehicles has not been efficiently recovered.
[0006] Therefore, a commercial vehicle integrated axle with a transmission function and an energy recovery device is designed. It has the advantages of a large reduction ratio, energy recovery during braking, reduced brake heat, and improved safety during steep descent. Therefore, this solution has significant economic benefits. Summary of the Invention
[0007] This invention addresses the shortcomings of existing technologies by providing a commercial vehicle integrated axle with a transmission function and energy recovery device. This axle features a large reduction ratio, energy recovery during braking, reduced brake heat, and improved safety during steep descents. By placing the reducer before the differential, employing a planetary reducer and a multi-gear design, it saves chassis space, increases the reduction ratio range, and incorporates an energy recovery device to reduce heat generated by brake friction, thereby enhancing vehicle safety.
[0008] This invention discloses an integrated axle for commercial vehicles with a transmission function and an energy recovery device. The integrated axle comprises a reducer and a differential device, characterized in that: The reducer consists of a reduction gear and an energy recovery device; the reduction gear adopts a planetary reduction gear train, and the input shaft is reduced and torque increased by the planetary reduction gear train; it is equipped with a driving gear and a gentle slope gear to provide an appropriate reduction ratio for the vehicle to descend steep slopes; the energy recovery device is equipped with a generator for recovering energy when the vehicle brakes; the differential device distributes the output torque of the reduction gear to the output half shaft through the differential gear train to achieve differential speed.
[0009] The reduction gear includes: a first planetary carrier, a first motor, a sun gear, a double planetary gear, a second planetary carrier, a first brake pad, a second brake pad, a ramp gear, an output bevel gear, a travel gear, and a reducer housing; The deceleration device is configured as follows: The first motor output shaft and the sun gear are fixedly connected to the first clutch. The first motor is mounted outside the reducer housing. The sun gear is connected to the first planetary carrier via a bearing. The sun gear meshes with the left gear of the double planetary gear set. The double planetary gear set is mounted on the first planetary carrier and the second planetary carrier via bearings. The first planetary carrier is connected to the reducer housing via bearings. The right gear of the double planetary gear meshes with the ramp stop gear and the travel gear. The ramp stop gear is fixedly connected to the second brake pad, and the travel gear is fixedly connected to the first brake pad. The second planetary carrier passes through the center hole of the ramp gear via a bearing, and is also connected to the output bevel gear via a key connection through the reducer housing via the bearing. The energy recovery device includes: a second motor, a generator driven gear, and a generator driving gear; The energy recovery device is configured as follows: The motor drive gear is mounted on the first planetary carrier, and the generator drive gear meshes with the generator driven gear; The generator driven gear and the second motor input shaft are fixedly connected to the second clutch; the second motor is mounted outside the reducer housing.
[0010] The outer rings of the first and second brakes are fixedly connected to the housing; the first brake is engaged with the first brake pad, and the second brake is engaged with the second brake pad; The integrated axle for commercial vehicles with a speed-changing function and an energy recovery device is also characterized in that: the speed reduction device realizes the switching between driving gear and gentle slope gear and energy recovery through the first brake, the second brake, the first clutch and the second clutch; The components of the driving gear are configured as follows: the first brake and the first clutch are energized and engaged, and the second brake and the second clutch are de-energized and disengaged; the driving gear is fixed to the first brake pad; the first motor drives the sun gear to rotate, and the sun gear, the left gear of the double planetary gear, the right gear of the double planetary gear, and the driving gear are all in a meshing state, while the ramp gear rotates freely; When the ramp shifts, the components are configured as follows: the second brake and the first clutch are energized and engaged, and the first brake and the second clutch are de-energized and disengaged; the ramp shift gear is fixed to the second brake pad; the first motor drives the sun gear to rotate, and the sun gear, the left gear of the double planetary gear, the right gear of the double planetary gear, and the ramp shift gear are all in a meshing state, while the driving gear rotates freely; During energy recovery, the components are configured as follows: the second clutch is energized and engaged, while the first brake, the second brake, and the first clutch are de-energized and disengaged; the differential half-shaft drives the driven bevel gear to rotate via the differential, the driven bevel gear drives the second planetary carrier to rotate, and the sun gear, the travel gear, and the ramp gear idle; the generator drive gear and the generator driven gear are in a meshing state, driving the generator driven gear to rotate.
[0011] 1. This invention uses a planetary gear system to achieve the speed reduction function. Compared with the single-stage gear reducer, the structure of the planetary gear system is more compact. It provides a larger reduction ratio while ensuring that the volume does not exceed that of a single-stage gear reducer and the radial dimension is small. In addition, the structure is simple, the number of parts is small, maintenance is convenient, and the service life is long.
[0012] 2. This invention incorporates a driving gear and a ramp gear in the reducer. The driving gear is suitable for driving on normal flat roads, while the ramp gear is typically used when the vehicle is descending steep slopes, especially during long downhill drives. The ramp gear avoids the excessive heat generated by frequent braking, thereby reducing wear and tear on brake components and extending their lifespan, while also mitigating the risk of brake failure. Furthermore, using the ramp gear allows for smoother vehicle operation, enabling the driver to better control the vehicle when encountering bumpy or uneven road surfaces.
[0013] 3. This invention incorporates a generator within the reducer. During braking, the connection between the reducer and the main shaft is disconnected, allowing the half-shaft to drive the generator main shaft to rotate via the differential and reducer. This achieves both deceleration and energy recovery, improving vehicle economy, reducing fuel costs, and exhibiting more significant energy-saving effects in frequent start-stop conditions such as urban driving. The energy recovery device also reduces the heat generated by friction between the brake discs and brake pads, thereby extending the service life of these components and reducing maintenance costs. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a power transmission route diagram for the travel gear of the reducer of the present invention; Figure 3 This is a power transmission route diagram for the ramp gear of the reducer of the present invention; Figure 4 This is a power transmission route diagram for the energy recovery state of the reducer in this invention; The diagram labels are as follows: 101 First planetary carrier; 102 First motor; 103 Sun gear; 104 Second motor; 105 Generator driven gear; 106 Double planetary gear; 107 Second planetary carrier; 108 First brake pad; 109 Second brake pad; 110 Slow-down gear; 111 Output bevel gear; 112 Travel gear; 113 Generator drive gear; 114 Reducer housing; 201 Differential housing; 202 Half-shaft gear; 203 Half-shaft; 204 Planetary gear; 205 Cross shaft; 206 Driven bevel gear; B1 First brake; B2 Second brake; C1 First clutch; C2 Second clutch. Detailed Implementation
[0015] In this embodiment, the integrated commercial vehicle axle with transmission function and energy recovery device mainly consists of a reducer and a differential. See attached diagram below. Figure 1 The implementation method will be further explained.
[0016] like Figure 1 As shown, the output shaft of the first motor 102 and the sun gear 103 are fixedly connected to the first clutch C1. The first motor 102 is mounted outside the reducer housing 114. The sun gear 103 is connected to the first planetary carrier 101 via a bearing, and the first planetary carrier 101 is connected to the reducer housing 114 via a bearing. The sun gear 103 meshes with the left gear of the double planetary gear 106. The double planetary gear 106 is mounted on the first planetary carrier 101 and the second planetary carrier 107 via bearings. The first planetary carrier 101 has a generator drive gear 113, which meshes with the generator driven gear 105. The generator driven gear 105 and the input shaft of the second motor 104 are fixedly connected to the second clutch C2. The right gear of the double planetary gear 106 meshes with the ramp gear 110 and the travel gear 112; the ramp gear 110 is fixedly connected to the second brake pad 109; and the travel gear 112 is fixedly connected to the first brake pad 108. The second planetary carrier 107 passes through the center hole of the ramp gear 110 via a bearing and is connected to the reducer housing 114 via the bearing. The second planetary carrier 107 is provided with a driving bevel gear that meshes with the driven bevel gear 206 of the differential; the cross shaft 205 is fixedly connected to the differential housing 201; the planetary gear 204 is mounted on the cross shaft 205 via a bearing; the planetary gear 204 meshes with the half-shaft gear 202; the half-shaft gear 202 is fixedly connected to the half-shaft 203 via a spline; the half-shaft gear 202 is connected to the differential housing 201 via a bearing.
[0017] Working principle: Based on the speed requirements of existing vehicle models and the deceleration requirements of special road conditions, the number of gear teeth is designed as shown in Table 1.
[0018] Table 1 Gear Tooth Count Table Number of teeth 18 18 57 31 17 Gear Name driving gear Slow slope gear Half-shaft gear Planetary gears Number of teeth 66 32 22 31 The actuators for each gear are shown in Table 2.
[0019] Table 2 Actuator Worksheet Drive gear ● ○ ● ○ gentle slope retaining wall ○ ● ● ○ Energy recovery ○ ○ ○ ● Note: In the table, "●" indicates combination, and "○" indicates separation; Based on Tables 1 and 2, the various working statuses are described as follows: (a) Driving gear 1. Drive gear In driving mode, the first motor 102 rotates forward, and the first brake B1 and the first clutch C1 are energized and engaged; the second brake B2 and the second clutch C2 are de-energized and remain disengaged; the first motor 102 outputs power to drive the sun gear 103 to rotate through the input shaft. The sun gear 103, the left gear of the double planetary gear 106, the right gear of the double planetary gear 106, and the driving gear 112 are all in a meshing state, driving the ramp gear 110 to idle; the driving gear 112 is fixed, and the second planetary carrier 107 rotates around the output shaft with the double planetary gear 106, transmitting power to the differential through the output bevel gear 111.
[0020] 2. Gentle slope retaining wall In the gentle slope gear, the first motor 102 rotates forward, and the second brake B2 and the first clutch C1 are energized and engaged; the first brake B1 and the second clutch C2 are de-energized and remain disengaged; the first motor 102 outputs power to drive the sun gear 103 to rotate through the input shaft, and the sun gear 103, the left gear of the double planetary gear 106, the right gear of the double planetary gear 106, and the gentle slope gear 110 are all in a meshing state, driving the driving gear 112 to rotate freely; the gentle slope gear 110 is fixed, and the second planetary carrier 107 rotates around the output shaft with the double planetary gear 106, transmitting power to the differential through the output bevel gear 111.
[0021] (ii) Energy recovery When the vehicle brakes, the first motor 102 stops, and the second clutch C2 is energized and engaged; the first brake B1, the second brake B2, and the first clutch C1 are de-energized and remain disengaged; the differential half-shaft 203 drives the driven bevel gear 206 to rotate through the differential, and the driven bevel gear 206 drives the second planetary carrier 107 to rotate; the generator drive gear 113 and the generator driven gear 105 are in a meshing state, and the sun gear 103, the travel gear 112, and the ramp gear 110 idle; the generator driven gear 105 transmits power to the generator energy storage through the generator input shaft.
Claims
1. A commercial vehicle integrated axle with transmission function and energy recovery device, wherein the integrated axle comprises a reducer and a differential device, characterized in that... The reducer consists of a reduction gear and an energy recovery device; the reduction gear adopts a planetary reduction gear train, and the input shaft is reduced in speed and increased in torque by the planetary reduction gear train; it is equipped with a driving gear and a gentle slope gear to provide an appropriate reduction ratio for the vehicle to descend steep slopes; the energy recovery device is equipped with a generator for recovering energy when the vehicle brakes; The differential device distributes the output torque of the reduction device to the output half-shaft through the differential gear train, thereby achieving differential speed. The reduction gear includes: a first planetary carrier (101), a first motor (102), a sun gear (103), a double planetary gear (106), a second planetary carrier (107), a first brake pad (108), a second brake pad (109), a ramp gear (110), an output bevel gear (111), a travel gear (112), and a reducer housing (114); the reduction gear is configured as follows: The output shaft of the first motor (102) and the sun gear (103) are fixedly connected to the first clutch (C1). The first motor (102) is installed outside the reducer housing (114). The sun gear (103) is connected to the first planetary carrier (101) through a bearing. The sun gear (103) meshes with the left gear of the double planetary gear (106). The double planetary gear (106) is mounted on the first planetary carrier (101) and the second planetary carrier (107) by bearings. The first planetary carrier (101) is connected to the reducer housing (114) by bearings. The right gear of the double planetary gear (106) meshes with the ramp gear (110) and the travel gear (112). The ramp gear (110) is fixedly connected to the second brake pad (109), and the travel gear (112) is fixedly connected to the first brake pad (108). The second planetary carrier (107) passes through the center hole of the ramp gear (110) via a bearing and passes through the reducer housing (114) via a bearing. The end of the second planetary carrier (107) is keyed to the output bevel gear (111). The energy recovery device includes: a second motor (104), a generator driven gear (105), and a generator driving gear (113); the energy recovery device is configured as follows: The motor drive gear (113) is mounted on the first planetary carrier (101), and the generator drive gear (113) meshes with the generator driven gear (105); The generator driven gear (105) and the input shaft of the second motor (104) are fixedly connected to the second clutch (C2); the second motor (104) is mounted outside the reducer housing (114); The outer ring of the first brake (B1) and the outer ring of the second brake (B2) are fixedly connected to the housing; the first brake (B1) cooperates with the first brake pad (108), and the second brake (B2) cooperates with the second brake pad (109).
2. The integrated commercial vehicle axle with transmission function and energy recovery device as described in claim 1, characterized in that: The deceleration device achieves switching between driving gear and gentle slope gear and energy recovery through the first brake (B1), the second brake (B2), the first clutch (C1), and the second clutch (C2); The components of the driving gear are configured as follows: the first brake (B1) and the first clutch (C1) are energized and engaged, while the second brake (B2) and the second clutch (C2) are de-energized and disengaged; the driving gear (112) is fixed to the first brake pad (108); the first motor (102) drives the sun gear (103) to rotate, and the sun gear (103), the left gear of the double planetary gear (106), the right gear of the double planetary gear (106), and the driving gear (112) are all in a meshing state, while the ramp gear (110) idles. When the ramp shifts, the components are configured as follows: the second brake (B2) and the first clutch (C1) are energized and engaged, and the first brake (B1) and the second clutch (C2) are de-energized and disengaged; the ramp shift gear (110) is fixed to the second brake pad (109); the first motor (102) drives the sun gear (103) to rotate, and the sun gear (103), the left gear of the double planetary gear (106), the right gear of the double planetary gear (106), and the ramp shift gear (110) are all in a meshing state, while the driving gear (112) idles. During energy recovery, the components are configured as follows: the second clutch (C2) is energized and engaged, while the first brake (B1), the second brake (B2), and the first clutch (C1) are de-energized and disengaged; the differential half-shaft (203) drives the driven bevel gear (206) to rotate via the differential, and the driven bevel gear (206) drives the second planetary carrier (107) to rotate; the sun gear (103), the travel gear (112), and the ramp gear (110) idle; the generator drive gear (113) and the generator driven gear (105) are in a meshing state, driving the generator driven gear (105) to rotate.