New energy vehicle speed reducer and design method thereof

Abstract

The application provides a new energy automobile speed reducer, which comprises a dog clutch, a primary reduction gear, a secondary reduction gear and a differential mechanism, the primary reduction gear and the dog clutch are arranged on the output shafts on the two sides of the differential mechanism, the dog clutch is located between the primary reduction gear and the differential mechanism, the primary reduction gears on the output shafts on the two sides of the differential mechanism are respectively in gear connection with a secondary reduction gear, the two secondary reduction gears are connected through a supporting mechanism and are arranged in the middle of the two primary reduction gears through the differential mechanism, the differential mechanism is not directly connected with the wheels of the vehicle, the torque borne by the differential mechanism is reduced, the rotating speed of the differential mechanism is improved, the rotating speed of the differential mechanism is improved but the torque is reduced, the differential mechanism does not need higher structural strength, thereby the weight and the overall size of the differential mechanism are reduced, the structural arrangement and the manufacturing cost of the whole speed reducer are reduced, and the lightweight and small-size design of the vehicle are facilitated.

Description

Technical Field

[0001] This invention belongs to the field of new energy vehicle technology, specifically relating to a new energy vehicle reducer and its design method. Background Technology

[0002] The mainstream three-in-one drive technology solutions on the market currently use motor drive (P4 for rear drive). The input shaft is directly driven to the wheel end after two stages of reduction. This type of reducer mechanism does not consider differential self-locking, especially in rear drive solutions where self-locking must be considered. Therefore, it has certain functional defects, but it is suitable for conventional applications and has a high degree of technological maturity.

[0003] Differential mechanisms require high torque and therefore better structural strength, making it difficult to reduce the weight of related parts in the industry, which is not conducive to lightweight design.

[0004] As the market demand for large and medium-sized electric vehicles continues to grow, existing solutions are unable to meet the market demand, particularly in the following three aspects:

[0005] 1. If used as a rear-wheel drive system in a four-wheel drive system (P4 solution), the differential lock function cannot be achieved;

[0006] 2. The system has a small torque capacity, basically within 3000Nm, and there is little room for improvement in structure and layout;

[0007] 3. It is not conducive to modular design. Summary of the Invention

[0008] The purpose of this invention is to reduce the overall size of the reducer, lower manufacturing costs, and provide a reducer for new energy vehicles and its design method.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: a new energy vehicle reducer, comprising: a dog clutch, a first-stage reduction gear, a second-stage reduction gear, and a differential. The first-stage reduction gear and the dog clutch are both disposed on the output shafts on both sides of the differential mechanism, and the dog clutch is located between the first-stage reduction gear and the differential mechanism. The first-stage reduction gears located on the output shafts on both sides of the differential mechanism are respectively meshed with a second-stage reduction gear, and the two second-stage reduction gears are connected by a support mechanism.

[0010] Furthermore, the first-stage reduction gear is connected to the input shaft via a drive gear, and the input shaft is connected to the output end of the drive motor.

[0011] Furthermore, each of the secondary reduction gears is connected to a wheel via a half-shaft.

[0012] The present invention also provides a design method for a new energy vehicle reducer according to any one of claims 1 to 3, comprising:

[0013] Step 1: Move the differential mechanism forward so that it is directly connected to the first-stage reduction gear;

[0014] Step 2: Add dog clutches to the half-shafts on both sides of the differential mechanism;

[0015] Step 3: Add a first-stage reduction gear and a second-stage reduction gear, so that the first-stage reduction gear and the second-stage reduction gear are located on both sides of the differential mechanism.

[0016] Beneficial effects:

[0017] 1. By moving the differential forward to the first-stage reduction gear and directly driving it, the differential's rotational speed is increased, but the torque is reduced. This effectively reduces the structural strength of the differential, thereby reducing its weight and thus lowering the overall reducer structure layout and manufacturing cost, which is beneficial for lightweight vehicle design.

[0018] 2. By setting the first-stage reduction gear and the second-stage reduction gear on both sides of the differential, the entire structure of the reducer is made more compact, avoiding the design disadvantage of large axial space of the traditional differential design, thus reducing the overall size of the reducer and improving product compatibility.

[0019] 3. By adding dog clutches to the half-shafts on both sides of the differential, the differential lock function can be achieved while keeping costs low and without expanding the overall size of the reducer. Attached Figure Description

[0020] Figure 1 This is a system schematic diagram of a traditional speed reducer.

[0021] Figure 2 This is a system schematic diagram of the present invention.

[0022] 1. Dog-tooth clutch, 2. Drive motor, 3. Wheel, 4. Support mechanism, 5. First-stage reduction gear, 6. Second-stage reduction gear, 7. Input shaft, 8. Differential mechanism, 9. Drive gear. Detailed Implementation

[0023] The invention will now be further explained with reference to the accompanying drawings.

[0024] like Figure 1As shown, this is a traditional reducer commonly used in existing automobiles. A traditional reducer includes a primary reduction gear, a secondary reduction gear, and a differential mechanism, and the entire reducer is driven by a P4 motor. The differential mechanism is directly connected to the wheels on both sides, and the input power from the P4 motor must pass through the primary and secondary reduction gears before reaching the differential mechanism. This results in a low rotational speed and high torque for the differential mechanism. This necessitates a higher structural strength for the differential mechanism.

[0025] like Figure 2 As shown, based on a traditional reducer, this invention provides a new energy vehicle reducer, comprising: a dog clutch 1, a primary reduction gear 5, a secondary reduction gear 6, and a differential mechanism 8. The primary reduction gear 5 and the dog clutch 1 are both mounted on the output shafts on both sides of the differential mechanism 8, with the dog clutch 1 located between the primary reduction gear 5 and the differential 8. The primary reduction gear 5 on each of the output shafts on both sides of the differential mechanism 8 is meshed with a secondary reduction gear 6, and the two secondary reduction gears 6 are connected by a support mechanism 4. The drive motor 2 drives the primary reduction gears 5 located on the left and right sides of the differential 8 via a drive gear 9 and an input shaft 7, and the gears reach the wheels 3 after passing through the secondary reduction gears 6, thus realizing the basic function of the reducer in reducing speed and increasing torque.

[0026] In this embodiment, the differential mechanism 8 is moved forward and positioned between the two first-stage reduction gears 5. The differential mechanism 8 is not directly connected to the vehicle's wheels 3, which reduces the torque borne by the differential mechanism 8 and increases the rotational speed of the differential mechanism 8. This results in an increase in the rotational speed of the differential mechanism 8, but a decrease in torque, so that the differential mechanism 8 does not require higher structural strength, thereby reducing the weight and overall size of the differential, and thus reducing the overall reducer structure layout and manufacturing cost, which is beneficial to the lightweight and miniaturized design of the vehicle.

[0027] At the same time, a first-stage reduction gear 5 and a second-stage reduction gear 6 will be added and placed on both sides of the differential mechanism 8. The entire reduction system will be changed from a series system to a parallel system, making the entire structure of the reducer more compact. This avoids the design disadvantage of large axial space of the differential mechanism 8 in the traditional design, further reducing the overall size of the reducer and improving the product's compatibility.

[0028] The differential mechanism 8 also features dog clutches 1 on both sides of the half-shafts. When needed, the left and right half-shafts at both ends of the dog clutches 1 are synchronized via an electro-hydraulic actuator to lock the differential. Compared to traditional reducers using differential locking mechanisms, this method is more cost-effective and takes up less space, thus avoiding the need to expand the overall size of the reducer.

[0029] The present invention also provides a design method for a new energy vehicle reducer according to any one of claims 1 to 3, comprising:

[0030] Step 1: Move the differential mechanism forward so that it is directly connected to the first-stage reduction gear.

[0031] Step 2: Add dog clutches to the half-shafts on both sides of the differential mechanism.

[0032] Step 3: Add a first-stage reduction gear and a second-stage reduction gear, so that the first-stage reduction gear and the second-stage reduction gear are located on both sides of the differential mechanism.

[0033] The above design method reduces the torque borne by the differential mechanism 8 by moving the differential forward and adding dog-tooth clutches to the half-shafts on both sides of the differential. Then, a first-stage reduction gear and a second-stage reduction gear are added and positioned on both sides of the differential, thus obtaining the new energy vehicle reducer of this invention. In this new energy vehicle reducer, the differential mechanism 8 is moved forward and positioned between the two first-stage reduction gears 5. The differential mechanism 8 is not directly connected to the vehicle's wheels 3, reducing the torque borne by the differential mechanism 8 and increasing its rotational speed. This results in an increased rotational speed but decreased torque. This design eliminates the need for higher structural strength in the differential mechanism 8, thereby reducing the weight and overall size of the differential. This, in turn, lowers the overall reducer structure layout and manufacturing costs, which is beneficial for vehicle lightweighting and miniaturization. Furthermore, dog-tooth clutches are added to the half-shafts on both sides of the differential, achieving the differential lock function while maintaining low cost and without expanding the overall size of the reducer. The first-stage and second-stage reduction gears are also located on both sides of the differential, making the entire reducer structure more compact. This avoids the design disadvantage of large axial space in traditional differential designs, reducing the overall size of the reducer and improving product compatibility.

[0034] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A speed reducer for new energy vehicles, characterized in that, include: The gear includes a dog clutch (1), a first-stage reduction gear (5), a second-stage reduction gear (6), and a differential mechanism (8). The first-stage reduction gear (5) and the dog clutch (1) are both located on the output shafts on both sides of the differential mechanism (8). The dog clutch (1) is located between the first-stage reduction gear (5) and the differential mechanism (8). The first-stage reduction gear (5) located on the output shafts on both sides of the differential mechanism (8) is meshed with a second-stage reduction gear (6). The two second-stage reduction gears (6) are connected by a support mechanism (4). The first-stage reduction gear (5) is connected to the input shaft (7) via the drive gear (9), and the input shaft (7) is connected to the output end of the drive motor (2); Each of the two-stage reduction gears (6) is connected to a wheel (3) via a half-shaft; The dog clutch (1) is used to synchronize the two half shafts through an electro-hydraulic actuator when the vehicle needs it, thereby locking the differential. The differential mechanism (8) is moved forward and positioned between the two first-stage reduction gears (5). The differential mechanism (8) is not directly connected to the vehicle's wheels (3), which reduces the torque borne by the differential mechanism (8) and increases the rotational speed of the differential mechanism (8).

2. A design method for the new energy vehicle reducer as described in claim 1, characterized in that, include: Step 1: Move the differential mechanism forward so that it is directly connected to the first-stage reduction gear; Step 2: Add dog clutches to the half-shafts on both sides of the differential mechanism; Step 3: Add a first-stage reduction gear and a second-stage reduction gear, so that the first-stage reduction gear and the second-stage reduction gear are located on both sides of the differential mechanism.

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