Driving wheel assembly of electric carrier
By improving the assembly structure of the drive wheel assembly of the electric pallet truck, the problems of rapid wheel wear and difficult disassembly have been solved, the gear transmission has been simplified, costs and energy consumption have been reduced, and the service life of the motor and gearbox has been extended.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-30
- Publication Date
- 2026-03-13
AI Technical Summary
In existing electric pallet truck drive wheel assemblies, the wheels wear out quickly and require frequent replacement, and disassembly is difficult. The gearbox has a complex structure and high cost. Increased load weight leads to increased energy consumption, and the high starting torque of the motor affects its lifespan.
The system adopts a combined structure of motor unit, gearbox unit, first bracket, drive wheel unit and support unit. The support unit is designed using the space of the gearbox unit to avoid the motor blocking wheel disassembly, simplify gear transmission and reduce weight burden.
It achieves convenient wheel disassembly, compact structure, reduced cost, reduced energy consumption, and extended life of motor and gearbox.
Smart Images
Figure CN121650433A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of logistics handling vehicles, and more specifically to the drive wheel assembly of an electric handling vehicle. Background Technology
[0002] Electric pallet jacks are widely used material handling equipment in industrial and logistics fields. Their core function is to move goods using electric power. Electric pallet jacks typically consist of a chassis, drive system, control system, and forks. Powered by batteries, they can load, unload, and transport goods without manual pushing. Compared to traditional manual pallet jacks (hydraulic pallet trucks), electric pallet jacks offer significant advantages such as easier operation, higher efficiency, and lower noise, making them particularly suitable for high-frequency, heavy-duty material handling scenarios.
[0003] Electric pallet jacks are driven by an electric motor, typically integrating the motor and wheel into a single unit. The current integrated structure of the motor and wheel on electric pallet jacks includes an input shaft, mounting bracket, gearbox, and a transmission mechanism housed within the gearbox. A fixed shaft is mounted on the input shaft, and an output shaft is mounted on the fixed shaft. A wheel seat, rotating synchronously with the output shaft, is mounted at one end of the output shaft. The wheel is detachably fixed to the wheel seat. The wheel seat, output shaft, and fixed shaft are rotatably connected, and the input shaft and output shaft are connected via a transmission mechanism. A motor mounting base is located at one end of the fixed shaft, and the motor is fixed to the motor mounting base. The gearbox includes a left gearbox, a middle gearbox, and a right gearbox. The other end of the input shaft passes through the middle gearbox and is located in the right cavity formed by the middle gearbox and the right gearbox. The two ends of the first gear shaft are supported on the middle gearbox and the right gearbox respectively by bearings. One end of the second gear shaft passes through the middle gearbox and is located in the left cavity formed by the left gearbox and the middle gearbox, and the middle part and the other end are supported on the middle gearbox and the right gearbox by bearings. The input gear, the first intermediate gear, the second intermediate gear, and the third intermediate gear are located in the right cavity, and the output gear and the fourth intermediate gear are located in the left cavity.
[0004] For the above structure, since the wheel seat and the wheel fixed on the wheel seat are located between the motor and the gearbox, and the wheel is a consumable part, if the electric forklift is used frequently, the wheel will wear out more, and the wheel will need to be replaced approximately every six months. After removing the fastening screws between the wheel and the wheel seat, when pulling the wheel out along the axial direction of the wheel seat, the wheel will be blocked by the motor because the outer diameter of the motor is larger than the inner diameter of the wheel. Therefore, the motor must be removed before removing the wheel.
[0005] Furthermore, the reduction gearbox in the aforementioned electric jack drive wheel assembly employs a four-stage gear transmission structure, resulting in a complex structure, high cost, and heavy weight, which also increases energy consumption during use. In addition, the reduction gearbox bears the weight of the wheel seat and wheel in the electric jack drive wheel assembly. Since the load is transferred to the wheel, the load is indirectly transferred to the reduction gearbox, increasing its workload. The electric jack drive wheel assembly requires significant torque during startup, which negatively impacts the lifespan of both the motor and the reduction gearbox. Summary of the Invention
[0006] This invention provides an electric pallet truck drive wheel assembly, which is not obstructed by the motor when disassembling scrapped wheels or installing new wheels.
[0007] The technical solutions to the above technical problems are as follows: An electric pallet truck drive wheel assembly includes a motor unit, a transmission unit, a first bracket, a drive wheel unit, and a support unit. The motor unit is located on one side of the first bracket and fixed to it. The transmission unit is located on the other side of the first bracket. The power input end of the transmission unit is circumferentially fixed to the torque output end of the motor unit. The drive wheel unit is fitted onto the transmission unit. The support unit includes a second bracket, a first support bearing, a second support bearing, and a first fastener. The second bracket includes a second support ring. One end of the second support ring is fixed with a first boss, and the other end is fixed with a second boss. The outer diameter of the first boss is larger than the outer diameter of the second support ring, and the outer diameter of the second boss is smaller than the outer diameter of the second support ring. The first support bearing and the second support bearing are located inside the support unit and fixed to it. The drive wheel unit is fitted onto the second support ring and fixed to the first boss by the first fastener. The torque output end of the transmission unit is fitted onto the second boss and fixed to the support unit. The first support bearing is located inside the transmission unit and fixed to it. The second support bearing is fitted onto the first bracket and fixed to it.
[0008] In this invention, the space of the transmission unit is fully utilized. A portion of the second support ring and the second support sleeve in the support unit are fitted inside the rotor of the transmission unit. The third bracket is fixed to the first bracket, and the first support sleeve in the third bracket supports the first support bearing in the support unit. The support tube in the first bracket supports the second support bearing, ensuring that the first support bearing is located inside the rotor, and the second support bearing is installed close to the first support bearing. This avoids placing the first and second support bearings on or outside the outer circumference of the rotor. Therefore, the structure of this invention makes the product compact and reduces its size, while also preventing any part in the transmission unit from obstructing the drive wheel unit in the axial direction. When the drive wheel unit needs to be disassembled, the entire drive wheel unit is moved towards the end cover. During this process, since the outer diameter of the rotor is the maximum diameter of the transmission unit, and the inner diameter of the hub is larger than the outer diameter of the rotor, the rotor will not obstruct the hub, making assembly and disassembly convenient. This avoids the need to disassemble the motor unit before disassembling the drive wheel unit, as required in the prior art. Attached Figure Description
[0009] Figure 1 This is a perspective view of the electric pallet truck drive wheel assembly of the present invention.
[0010] Figure 2 This is a cross-sectional view of the drive wheel assembly of the electric pallet truck of the present invention.
[0011] Figure 3 This is a cross-sectional view of the motor unit.
[0012] Figure 4 This is a cross-sectional view of the transmission unit, the first bracket, and the support unit.
[0013] Figure 5 This is a cross-sectional view of the third support structure.
[0014] Figure 6 This is a cross-sectional view of the first support structure.
[0015] Figure 7 This is a three-dimensional view of the supporting unit.
[0016] Figure 8 This is a cross-sectional structural diagram of the support unit.
[0017] The markings in the attached diagram are as follows: Motor unit A, motor body 10, motor end cover 11, exhaust port 11a, connecting sleeve 12, cover 13, power failure brake 14; Gearbox unit B, first step B1, drive shaft 20, first bearing 21, third bracket 22, first support sleeve 22a, first connecting sleeve 22b, second connecting sleeve 22c, shoulder 22d, first screw hole 22e, exhaust port 22f, first screw 22g, second screw 22h, end cover 23, rotor 24, sun gear 25, double planetary gear 26, first planetary gear 26a, second planetary gear 26b, planetary gear 26a, first planetary gear 26b, second planetary gear 26a, second ... Frame 27, first gear ring 28, second gear ring 29; first bracket C, groove C1, second step C2, first bracket body 31, receiving groove 32, support tube 33, mounting hole 34; drive wheel unit D, hub 41, tire 42, support unit E, second bracket 51, second support ring 51a, first boss 51b, second boss 51c, first positioning protrusion 51d, second support sleeve 51e, second positioning protrusion 51f, first support bearing 52, second support bearing 53, first fastener 54; exhaust port F, one-way valve G, first sealing ring H, second sealing ring I. Detailed Implementation
[0018] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0019] like Figures 1 to 8 As shown, the electric pallet truck drive wheel assembly of the present invention includes a motor unit A, a transmission unit B, a first bracket C, a drive wheel unit D, and a support unit E. The following is a detailed description of each part and the relationship between them.
[0020] Motor unit A is located on one side of the first bracket C and fixed to the first bracket C. Motor unit A includes a motor body 10, a motor end cover 11, and a connecting sleeve 12. The motor body 10 is fixed to the motor end cover 11, and the motor end cover 11 is fixed to the first bracket C by screws or rivets. In this embodiment, the motor end cover 11 is preferably fixed to the first bracket C by screws. The connecting sleeve 12 passes through the first bracket C and is clearance-fitted with the first bracket C. The connecting sleeve 12 is circumferentially fixed to the torque output shaft of the motor body 10 and the power input end of the transmission unit B, respectively. The connecting sleeve 12 is preferably connected to the torque output shaft of the motor body 10 via screws. The spline connection allows the connecting sleeve 12 to be circumferentially fixed to the torque output shaft of the motor body 10. When the motor unit A malfunctions and needs to be disassembled, it is only necessary to remove the screws that fasten the motor unit A to the first bracket C to separate the motor unit A from the first bracket C. During the separation process, the motor unit A will not be obstructed by any of the gearbox unit B, the first bracket C, the drive wheel unit D, or the support unit E. Similarly, it will not be obstructed during the assembly process with the first bracket C. Therefore, this structure has the advantage of convenient assembly and disassembly for the motor unit A.
[0021] Motor unit A also includes a housing 13 and a power-off brake 14. The housing 13 is fixed to the motor body 10, forming a first cavity between the housing 13 and the motor body 10. The power-off brake 14 is located within the first cavity and is connected to the torque output shaft of the motor body 10. When the power-off brake 14 is energized, it releases the braking force. When the power-off brake 14 is de-energized, it generates a braking force, preventing the torque output shaft of the motor body 10 from rotating.
[0022] The transmission unit B is located on the other side of the first bracket C. The power input end of the transmission unit B is circumferentially fixed to the torque output end of the motor unit A. The transmission unit B includes a drive shaft 20, a first bearing 21, a third bracket 22, a planetary transmission mechanism, an end cover 23, and a rotor 24 with a cavity. The drive shaft 20 is connected to the torque output end of the motor unit A. One end of the drive shaft 20 is the power input end of the transmission unit B. One end of the drive shaft 20 is preferably connected to the connecting sleeve 12 in the motor unit A via a spline.
[0023] After passing through the first bearing 21 and the planetary transmission mechanism, the drive shaft 20 is movably connected to the end cover 23. The inner ring of the first bearing 21 is fixed to the drive shaft 20. The third bracket 22 is fitted onto the first bearing 21 and fixed to the first bearing 21. The third bracket 22 is fitted onto the outer ring of the first bearing 21 and fixed to the first bearing 21. The third bracket 22 and the first bracket C are preferably fixed by screws. During operation, the third bracket 22 will not rotate.
[0024] The third bracket 22 includes a first support sleeve 22a, a first connecting sleeve 22b, and a second connecting sleeve 22c. The first support sleeve 22a is fitted onto and fixed to the first bearing 21. One end of the first connecting sleeve 22b is fixed to the first support sleeve 22a. Both the inner and outer circumferential surfaces of the first connecting sleeve 22b are conical surfaces. The other end of the first connecting sleeve 22b is fixed to the second connecting sleeve 22c. A shoulder 22d is formed between the first connecting sleeve 22b and the second connecting sleeve 22c. A mounting portion for mounting a planetary transmission mechanism is formed between the second connecting sleeve 22c and the shoulder 22d.
[0025] The planetary transmission mechanism is movably connected to the transmission shaft 20. The planetary transmission mechanism is fixedly connected to the third support 22 and the rotor 24 respectively. One end of the rotor 24 is fixed to the end cover 23. The other end of the rotor 24 is fitted onto the second boss 51c of the support unit E and then fixed to the support unit E. The rotor 24 is cylindrical. The first bearing 21 and the planetary transmission mechanism are located in the cavity of the rotor 24. The transmission shaft 20 and a part of the third support 22 are located in the cavity of the rotor 24.
[0026] The planetary transmission mechanism includes a sun gear 25, a double planetary gear 26, a planet carrier 27, a first gear ring 28, and a second gear ring 29. The sun gear 25 is fixed to the transmission shaft 20. The double planetary gear 26 is connected to the planet carrier 27. The planet carrier 27 is fitted onto the transmission shaft 20 and is movably connected to the transmission shaft 20. There are two planet carriers 27. Each planet carrier 27 consists of a planet carrier body and a bearing. The inner ring of the bearing is fitted onto the transmission shaft 20 and is fixed to the transmission shaft 20. The planet carrier body is fitted onto the outer ring of the bearing and is fixed to the outer ring. In the double planetary gear 26, the first planetary gear 26a meshes with the sun gear 25 and the first gear ring 28 respectively. The first gear ring 28 is fixed to the third support 22. In the double planetary gear 26, the second planetary gear 26b meshes with the second gear ring 29. The second gear ring 29 is fixed to the rotor 24.
[0027] The planetary transmission mechanism of the present invention uses a third bracket 22 to fix the first gear ring 28 and allows the first planetary gear 26a to mesh with the sun gear 25 and the first gear ring 28 respectively. The rotor 24 is used to fix the second gear ring 29 and allows the second planetary gear 26b to mesh with the second gear ring 29. This structure not only gives the transmission unit B two-stage transmission ratio, but also has a simpler structure and lower cost than the gear transmission mechanism in the prior art.
[0028] The drive wheel unit D is fitted onto the transmission unit B. The drive wheel unit D includes a hub 41 and a tire 42. The inner diameter of the hub 41 is larger than the outer diameter of the rotor 24 of the transmission unit B. The tire 42 is fitted onto the hub 41 and fixed to the hub 41.
[0029] The support unit E includes a second bracket 51, a first support bearing 52, a second support bearing 53, and a first fastener 54. The second bracket 51 includes a second support ring 51a. One end of the second support ring 51a is fixed with a first boss 51b, and the other end of the second support ring 51a is fixed with a second boss 51c. The first boss 51b is disposed on the circumferential surface of one end of the second support ring 51a, and the second boss 51c is disposed on the axial end surface of the other end of the second support ring 51a. The second support ring 51a, the first boss 51b, and the second boss 51c are integrally formed.
[0030] The first support bearing 52 and the second support bearing 53 are located within and fixed to the support unit E. The first support bearing 52 is located within and fixed to the transmission unit B. Preferably, a second support sleeve 51e is provided on the axial end face of the second boss 51c. A second positioning protrusion 51f is provided on the inner wall of the second support sleeve 51e. The second support sleeve 51e is located within the rotor 24 of the transmission unit B. The first support bearing 52 is located within the second support sleeve 51e. The outer ring of the first support bearing 52 is fixed to the second support sleeve 51e. The inner ring of the first support bearing 52 is fitted onto and fixed to the first support sleeve 22a in the third bracket 22. One end of the first support bearing 52 is axially positioned by the second positioning protrusion 51f. A first step B1 is provided on the first support sleeve 22a in the transmission unit B. The other end of the first support bearing 52 is axially positioned by the first step B1. The first support bearing 52 and the second support bearing 53 together support the second bracket 51, but the second bracket 51 is mainly supported by the second support bearing 53. The main function of the first support bearing 52 is to ensure that the support unit E, the transmission unit B and the first bracket C are concentric and to share the load-bearing capacity of the drive shaft 20.
[0031] The second support bearing 53 is fitted onto the first bracket C and fixed to the first bracket C. The inner ring of the second support bearing 53 is fitted onto the first bracket C and fixed to the first bracket C. The second support bearing 53 is located inside the second support ring 51a. The outer ring of the second support bearing 53 is fixed to the second support ring 51a. The inner wall of the second support ring 51a is provided with a first positioning protrusion 51d. One end of the second support bearing 53 is axially positioned by the first positioning protrusion 51d. The first bracket C is provided with a second step C2. The other end of the second support bearing 53 is axially positioned by the second step C2.
[0032] In this invention, the outer diameter of the first support bearing 52 is smaller than the outer diameter of the second support bearing 53. There are multiple second support bearings 53, for example, two are preferred. This makes the weight of the entire second bracket 51 mainly borne by the second support bearings 53. The second support bearings 53 are fitted onto the first bracket C and fixed to the first bracket C. Therefore, the weight of the support unit E and the drive wheel unit D fixed to the support unit E are both borne by the first bracket C. Compared with the electric pallet jack structure in the prior art, this structure in this invention avoids the transmission unit B mainly bearing the weight of the support unit E and the drive wheel unit D. In this invention, the transmission unit B is mainly used to transmit the torque of the motor unit A to the drive wheel unit D.
[0033] The first bracket C includes a first bracket body 31. One end of the first bracket body 31 is provided with a receiving groove 32. A part of the motor unit A is located in the receiving groove 32 and fixed to the first bracket body 31. The other end of the first bracket body 31 is provided with a support tube 33. The axial end face of the support tube 33 is provided with a mounting hole 34 that passes through the axial end face of the support tube 33. There are multiple mounting holes 34. A part of the support unit E is sleeved on the support tube 33 and supported by the support tube 33. The inner ring of the second support bearing 53 in the support unit E is sleeved on the support tube 33 and fixed to the support tube 33. The second step C2 is provided on the support tube 33.
[0034] In this embodiment, the third bracket 22 is provided with multiple first screw holes 22e and an exhaust hole 22f, with at least one first screw hole 22e communicating with the exhaust hole 22f. The electric pallet truck drive wheel assembly in this embodiment also includes a first screw 22g, a second screw 22h, and a one-way valve G. The first screw 22g passes through the first mounting hole 34 on the first bracket C and is threaded to the first screw hole 22e. The second screw 22h passes through the first mounting hole 34 on the first bracket C and is threaded to the first screw hole 22e. The second screw 22h is provided with a first through hole for exhaust, i.e., the second screw 22h is a hollow screw. There are one or more second screws 22h. In this embodiment, the number of second screws 22h is preferably one. The first bracket C or the motor unit A is provided with a groove C1. After the motor unit A is fixed to the first bracket C, an exhaust channel F is formed between the motor unit A and the first bracket C. The second screw 22h cooperates with the exhaust channel F.
[0035] In this embodiment, the groove C1 is provided on the first support body 31. After the motor end cover 11 in the motor unit A is fixed to the first support body 31, the exhaust passage F is formed between the motor end cover 11 and the first support body 31. The motor unit A is provided with an exhaust through hole 11a for communicating with the exhaust passage F. The exhaust through hole 11a is preferably provided on the motor end cover 11, and the one-way valve G is installed in the exhaust through hole 11a.
[0036] A first sealing ring H is provided between the first bracket C and the second support ring 51a, and a second sealing ring I is provided between the two first bearings 21. The transmission unit B contains lubricating oil, which is used to lubricate the planetary transmission mechanism. During operation, the lubricating oil releases gas. When the amount of gas is large, it will cause the internal pressure of the transmission unit B to increase, thereby causing the first sealing ring H to fail. Therefore, in order to prevent the first sealing ring H and the second sealing ring I from failing, a hollow second screw 22h is used in conjunction with the exhaust port F and the exhaust hole 11a to allow the gas generated in the transmission unit B to be discharged. In order to prevent outside air from entering the transmission unit B and causing the lubricating oil in the transmission unit B to become saturated, a one-way valve G is installed at the exhaust hole 11a.
[0037] After the drive wheel unit D is fitted onto the second support ring 51a, it is fixed to the first boss 51b by the first fastener 54. After the torque output end of the transmission unit B is fitted onto the second boss 51c, it is fixed to the support unit E. In this embodiment, the hub 41 in the drive wheel unit D is fitted onto the second support ring 51a and fixed to the first boss 51b by the first fastener 54. The rotor 24 of the transmission unit B is fitted onto the second boss 51c and fixed to the second support ring 51a by screws. Since the outer diameter of the first boss 51b is larger than the outer diameter of the second support ring 51a, and the outer diameter of the second boss 51c is smaller than the outer diameter of the second support ring 51a, the outer diameter of the rotor 24 is the maximum outer diameter of the transmission unit B. The hub 41 is loosely fitted onto the rotor 24. Therefore, when it is necessary to disassemble the drive wheel unit D, the entire drive wheel unit D is moved towards the end cover 23. During this process, the rotor 24 will not obstruct the hub 41, making assembly and disassembly very convenient.
[0038] The working process of this invention is as follows: When the motor body 10 receives power and outputs torque, it transmits it to the transmission shaft 20, causing the transmission shaft 20 to rotate. The sun gear 25, which is fixed on the transmission shaft 20, rotates with the transmission shaft 20. The sun gear 25 transmits power to the first planet gear 26a in the double planetary gear 26. The first planet gear 26a transmits power to the second planet gear 26b and the planet carrier 27. The second planet gear 26b drives the second ring gear 29 to rotate. The second ring gear 29 drives the rotor 24 to rotate. The rotor 24 drives the support unit E to rotate. The support unit E drives the drive wheel unit D to rotate.
[0039] In this invention, the space of the transmission unit B is fully utilized. A portion of the second support ring 51a and the second support sleeve 51e from the support unit E are assembled inside the rotor 24 of the transmission unit B. The third bracket 22 is fixed to the first bracket C, and the first support sleeve 22a in the third bracket 22 supports the first support bearing 52 in the support unit E. The support tube 33 in the first bracket C supports the second support bearing 53. This ensures that the first support bearing 52 is located inside the rotor 24, and the installation position of the second support bearing 53 is close to the first support bearing 52, avoiding placing the first and second support bearings 52 in the same position as the first support bearing 52. The rotor 24 is located on or outside its outer circumferential surface. Therefore, the structure of this invention makes the product compact and reduces its size, while also preventing any part in the transmission unit B from obstructing the drive wheel unit D in the axial direction. When the drive wheel unit D needs to be disassembled, the entire drive wheel unit D is moved toward the end cover 23. During this process, since the outer diameter of the rotor 24 is the maximum diameter of the transmission unit B, and the inner diameter of the hub 41 is larger than the outer diameter of the rotor 24, the rotor 24 will not obstruct the hub 41. This makes assembly and disassembly very convenient, avoiding the operation of disassembling the motor unit A before disassembling the drive wheel unit D, as required in the prior art.
[0040] In the structure of this invention, the motor unit A and the drive wheel unit D are independent parts. When it is necessary to install or remove the motor unit A or the drive wheel unit D, neither the motor unit A nor the drive wheel unit D will be obstructed by the gearbox unit B or the first bracket C.
Claims
1. An electric pallet truck drive wheel assembly, comprising a motor unit (A), a transmission unit (B), a first bracket (C), a drive wheel unit (D), and a support unit (E), wherein the motor unit (A) is located on one side of the first bracket (C) and fixed to the first bracket (C), the transmission unit (B) is located on the other side of the first bracket (C), the power input end of the transmission unit (B) is circumferentially fixed to the torque output end of the motor unit (A), and the drive wheel unit (D) is sleeved on the transmission unit (B), characterized in that, The support unit (E) includes a second bracket (51), a first support bearing (52), a second support bearing (53), and a first fastener (54). The second bracket (51) includes a second support ring (51a). One end of the second support ring (51a) is fixed with a first boss (51b), and the other end of the second support ring (51a) is fixed with a second boss (51c). The outer diameter of the first boss (51b) is larger than the outer diameter of the second support ring (51a), and the outer diameter of the second boss (51c) is smaller than the outer diameter of the second support ring (51a). The first support bearing... (52) The second support bearing (53) is located inside the support unit (E) and fixed to the support unit (E). The drive wheel unit (D) is fitted onto the second support ring (51a) and fixed to the first boss (51b) by the first fastener (54). The torque output end of the transmission unit (B) is fitted onto the second boss (51c) and fixed to the support unit (E). The first support bearing (52) is located inside the transmission unit (B) and fixed to the transmission unit (B). The second support bearing (53) is fitted onto the first bracket (C) and fixed to the first bracket (C).
2. The electric pallet truck drive wheel assembly according to claim 1, characterized in that, The motor unit (A) includes a motor body (10), a motor end cover (11), and a connecting sleeve (12). The motor body (10) is fixed to the motor end cover (11), the motor end cover (11) is fixed to the first bracket (C), the connecting sleeve (12) passes through the first bracket (C) and is clearance-fitted with the first bracket (C), and the connecting sleeve (12) is circumferentially fixed to the torque output shaft of the motor body (10) and the power input end of the transmission unit (B).
3. The electric pallet truck drive wheel assembly according to claim 1, characterized in that, The transmission unit (B) includes a drive shaft (20), a first bearing (21), a third bracket (22), a planetary transmission mechanism, an end cover (23), and a rotor (24) with a cavity. The drive shaft (20) is connected to the torque output end of the motor unit (A). After passing through the first bearing (21) and the planetary transmission mechanism, the drive shaft (20) is movably connected to the end cover (23). The third bracket (22) is fitted onto the first bearing (21) and fixed to the first bearing (21). The third bracket (22) is fixed to the first bracket (C). The first support bearing (52) is fitted onto... The planetary transmission mechanism is fixed on and to the third support (22), and is movably connected to the transmission shaft (20). The planetary transmission mechanism is fixedly connected to the third support (22) and the rotor (24) respectively. One end of the rotor (24) is fixed to the end cover (23), and the other end of the rotor (24) is fitted onto the second boss (51c) and then fixed to the support unit (E). The first bearing (21) and the planetary transmission mechanism are located in the cavity of the rotor (24), and the transmission shaft (20) and a part of the third support (22) are located in the cavity of the rotor (24).
4. The electric pallet truck drive wheel assembly according to claim 3, characterized in that, The third bracket (22) includes a first support sleeve (22a), a first connecting sleeve (22b), and a second connecting sleeve (22c). The first support sleeve (22a) is fitted onto the first bearing (21) and fixed to the first bearing (21). One end of the first connecting sleeve (22b) is fixed to the first support sleeve (22a), and the other end of the first connecting sleeve (22b) is fixed to the second connecting sleeve (22c). A shoulder (22d) is formed between the first connecting sleeve (22b) and the second connecting sleeve (22c), and a mounting portion for mounting the planetary transmission mechanism is formed between the second connecting sleeve (22c) and the shoulder (22d).
5. The electric pallet truck drive wheel assembly according to claim 3, characterized in that, The third bracket (22) is provided with multiple first screw holes (22e) and a vent hole (22f), and at least one first screw hole (22e) is connected to the vent hole (22f); It also includes a first screw (22g), a second screw (22h), and a one-way valve (G). The first screw (22g) passes through the first bracket (C) and is threaded into the first screw hole (22e). The second screw (22h) passes through the first bracket (C) and is threaded into the first screw hole (22e). The second screw (22h) is provided with a first through hole for venting. The first bracket (C) or the motor unit (A) is provided with a groove (C1). After the motor unit (A) is fixed to the first bracket (C), an exhaust passage (F) is formed between the motor unit (A) and the first bracket (C). The second screw (22h) cooperates with the exhaust passage (F). The motor unit (A) is provided with an exhaust through hole (11a) for communicating with the exhaust passage (F). The one-way valve (G) is installed in the exhaust through hole (11a).
6. The electric pallet truck drive wheel assembly according to claim 3, characterized in that, The planetary transmission mechanism includes a sun gear (25), a double planetary gear (26), a planet carrier (27), a first gear ring (28), and a second gear ring (29). The sun gear (25) is fixed to the transmission shaft (20). The double planetary gear (26) is connected to the planet carrier (27). The planet carrier (27) is fitted on the transmission shaft (20) and is movably connected to the transmission shaft (20). The first planetary gear (26a) in the double planetary gear (26) meshes with the sun gear (25) and the first gear ring (28) respectively. The first gear ring (28) is fixed to the third support (22). The second planetary gear (26b) in the double planetary gear (26) meshes with the second gear ring (29). The second gear ring (29) is fixed to the rotor (24).
7. The electric pallet truck drive wheel assembly according to claim 1, characterized in that, The first support (C) includes a first support body (31), one end of which is provided with a receiving groove (32). A part of the motor unit (A) is located in the receiving groove (32) and fixed to the first support body (31). The other end of the first support body (31) is provided with a support tube (33). The axial end face of the support tube (33) is provided with a mounting hole (34) that passes through the axial end face of the support tube (33). A part of the support unit (E) is sleeved on the support tube (33) and supported by the support tube (33).
8. The electric pallet truck drive wheel assembly according to claim 1, characterized in that, The second support ring (51a) has a first positioning protrusion (51d) on its inner wall. The second support bearing (53) is located inside the second support ring (51a). One end of the second support bearing (53) is axially positioned by the first positioning protrusion (51d). A second step (C2) is provided on the first bracket (C). The other end of the second support bearing (53) is axially positioned by the second step (C2).
9. The electric pallet truck drive wheel assembly according to claim 1, characterized in that, The second boss (51c) has a second support sleeve (51e) on its axial end face. The second support sleeve (51e) has a second positioning protrusion (51f) on its inner wall. The first support bearing (52) is located inside the second support sleeve (51e) and fixed to the second support sleeve (51e). One end of the first support bearing (52) is axially positioned by the second positioning protrusion (51f). A first step (B1) is provided on the transmission unit (B). The other end of the first support bearing (52) is axially positioned by the first step (B1).
10. The electric pallet truck drive wheel assembly according to claim 1, characterized in that, The outer diameter of the first support bearing (52) is smaller than the outer diameter of the second support bearing (53).