Wheel side reduction structure and engineering machine

Abstract

This invention relates to the field of speed reducer technology, and discloses a wheel-side speed reduction structure and engineering machinery, including a brake, a motor, and a wheel-side speed reducer arranged in sequence. The brake and the wheel-side speed reducer are respectively connected to both sides of the motor, and each set of wheel-side speed reducers is connected to at least two sets of motors. Each set of brakes is connected to an oil collection box via an oil pipe to drain excess oil from the brake. The brake is also equipped with an oil temperature sensor for detecting the oil temperature in the brake fluid chamber, and a pressure sensor for detecting the brake pressure. The addition of an oil collection box on one side of the brake increases the internal space of the chamber and allows excess oil to be drained, thereby better preventing the brake from overheating. If the oil level increases, the vehicle can operate normally after the excess oil is drained.

Description

Technical Field

[0001] This invention relates to the field of speed reducer technology, and in particular to a wheel-side speed reduction structure and engineering machinery. Background Technology

[0002] Currently, high-horsepower bulldozers, especially fully hydraulic or electric drive bulldozers, require a stable and reliable transmission system, as well as a reliable parking brake system. The brake, as a unit, can be integrated with the wheel-side reducer, i.e., motor → brake → wheel-side reducer. In this solution, the brake is integrated into the wheel-side reducer. If the brake fails, it will affect the reducer, and the parts generated by the brake will damage the wheel-side reducer, thus affecting the reliability of the entire transmission system. During maintenance, the entire brake and wheel-side reducer need to be replaced. Summary of the Invention

[0003] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a wheel-side reduction structure and engineering machinery, in which only the brake needs to be replaced when the brake is damaged, without damaging the wheel-side reducer.

[0004] To achieve the above objectives, the present invention is implemented through the following technical solution: In a first aspect, a wheel-side reduction structure includes a brake, a motor, and a wheel-side reducer arranged sequentially. The brake and the wheel-side reducer are respectively connected to both sides of the motor, and each set of wheel-side reducers is connected to at least two sets of motors. Each set of brakes is connected to an oil collection box via an oil pipe to drain excess oil from inside the brake. The brake is also equipped with an oil temperature sensor for detecting the oil temperature in the brake fluid chamber, and a pressure sensor for detecting the braking pressure.

[0005] As a further implementation, the wheel-side reducer includes a first-stage reduction gear, a first planetary gear set, a second planetary gear set, and a third planetary gear set that are sequentially coupled. The first-stage reduction gear includes two pairs of meshing gears, namely a driving gear and a driven gear. There are two driving gears, which are respectively connected to the two motor sides. The two driving gears mesh with one driven gear to form a power confluence structure.

[0006] As a further implementation, the first, second, and third planetary gear sets all have a structure where the sun gear inputs power, the ring gear is fixed, and the planet carrier outputs power, with the three planetary gear sets connected in series.

[0007] As a further implementation, the brake is a normally closed disc spring brake, and the oil temperature sensor and pressure sensor are both arranged on the brake housing.

[0008] As a further implementation, the brake housing is provided with a brake oil pressure port, through which a pressure sensor is connected.

[0009] As a further implementation, the brake is provided with a pressure plate on the side away from the motor, and the pressure plate is provided with an oil pipe interface, through which an oil pipe is connected, and the oil pipe interface is connected to the lubricating oil chamber inside the brake.

[0010] As a further implementation, the brake housing is provided with a spline sleeve inside, and a friction plate, an outer toothed plate, and an inner toothed ring that mesh with the outer toothed plate are arranged sequentially from the inside to the outside along the radial direction of the spline sleeve.

[0011] As a further implementation, the brake is fixedly connected to the motor via a transition plate.

[0012] As a further implementation, the wheel-side reducer is driven by dual motors.

[0013] Secondly, an engineering machine having a wheel-side speed reduction structure as described above.

[0014] The beneficial effects of the present invention are as follows: 1. This invention adds an oil collection box to one side of the brake, which increases the internal space of the cavity and allows excess oil to drain, thus better preventing brake overheating. If the oil level increases, the excess oil can be drained, and the vehicle can operate normally. Otherwise, the entire brake assembly needs to be replaced for repair. The brake is connected to the motor side, so if the brake is damaged, only the brake itself needs to be replaced, without damaging the wheel-side reducer. This invention also incorporates an oil temperature sensor and a pressure sensor on the brake. By measuring the oil temperature or pressure value and comparing it with a set value, a control strategy can be implemented, effectively solving brake problems. When the oil temperature measured by the sensor is higher than the design temperature, the oil temperature sensor alarms, the vehicle slows down, and the vehicle is stopped to check whether the overheating is caused by oil churning due to excessive oil or other reasons. When the brake pressure measured by the pressure sensor is lower than the design pressure, the pressure sensor alarms, and the vehicle slows down.

[0015] 2. The wheel-side reducer of the present invention adopts dual motor cooperative drive, which can be extended to dual motors. At the same time, the motors provide large braking, which greatly reduces the space and size of the braking torque of the brake, making it reliable and compact in structure. In addition to being used in bulldozers, the dual motor power can also be extended to other hybrid engineering machinery. Attached Figure Description

[0016] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0017] Figure 1 This is a schematic diagram of the wheel-side deceleration structure in an embodiment of the present invention; Figure 2 This is a functional block diagram of the wheel-side deceleration structure in an embodiment of the present invention; Figure 3 This is a schematic diagram of the wheel-side reduction gear transmission structure in an embodiment of the present invention; Figure 4 This is a logic diagram of brake oil level control in an embodiment of the present invention; Figure 5 This is a braking pressure control logic diagram in an embodiment of the present invention; Figure 6 This is a schematic diagram of the brake structure in an embodiment of the present invention; Figure 7 This is the vehicle driving control logic in this embodiment of the invention; Figure 8 This is a schematic diagram of the three-motor coordinated drive configuration in an embodiment of the present invention.

[0018] The diagram exaggerates the spacing or dimensions between parts to show their positions; the diagram is for illustrative purposes only.

[0019] The components are: Ⅰ. Brake unit, Ⅱ. Motor unit, Ⅲ. Transmission system unit; 100. Wheel-side reducer, 200. Motor, 300. Brake, 400. Oil pipe, 500. Oil collection box; 3. Drive gear, 4. Driven gear, 5. Sun gear, 6. Planet gear, 7. Planetary ring gear, 8. Planet carrier, 9. Sun gear, 10. Planet gear, 11. Planetary ring gear, 12. Planet carrier, 13. Sun gear, 14. Planet gear, 15. Planet carrier, 16. Planetary ring gear; 301. Brake housing, 302. Transition plate, 17. Spline sleeve, 18. External gear plate, 19. Friction plate, 20. Internal gear ring, 21. Pressure plate, 22. Pressure plate, 23. Disc spring, 24. Piston, 25. Retaining ring, 26. Pressure plate. Detailed Implementation

[0020] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0021] Example 1 In a typical embodiment of the present invention, reference is made to Figure 1 As shown, a wheel-side reduction structure mainly includes a brake unit I, a motor unit II, and a transmission system unit III, specifically a wheel-side reducer 100, a motor 200, a brake 300, an oil pipe 400, and an oil collection box 500. Brake unit I includes a brake 300, an oil pipe 400, and an oil collection box 500; motor unit II includes a motor 200; and transmission system unit III includes the wheel-side reducer 100.

[0022] Each set of wheel-side reducers is connected to at least two sets of motors; each set of brakes is connected to an oil collection box via an oil pipe to drain excess oil from inside the brake; the brakes are also equipped with an oil temperature sensor to detect the oil temperature in the brake fluid chamber and a pressure sensor, and the brake pressure is detected by the pressure sensor.

[0023] like Figure 1 As shown, the number of motors 200 and brakes 300 is the same. The brakes 300 are connected to one side of the motors, and the wheel-side reducer 100 is connected to the other side of the motors. In this embodiment, two sets of motors 100 and two sets of brakes 300 are correspondingly provided, and one set of wheel-side reducers 100 is provided. In other examples, a three-motor coordinated drive configuration can also be used. For example... Figure 8 As shown.

[0024] like Figure 2 As shown, transmission system unit III is fixedly connected to the main frame as a transmission system module, facilitating disassembly and maintenance. Transmission system III includes a single-stage reduction gear, a first planetary gear set, a second planetary gear set, and a third planetary gear set.

[0025] The brake unit I in this embodiment includes two independent brakes 300, each connected to one side of the motor 200. These brakes are normally closed parking brakes, containing multiple pairs of mating friction pads and polished pads. Each brake's side away from the motor is connected to an oil collection box 500 via an oil pipe 400. The oil collection box 500 has a breather that communicates with the outside, maintaining pressure balance between the inside and outside of the brake 300. Excess oil can also be drained via a switch on the oil collection box 500.

[0026] Motor 200 is an independent unit, with power output via splines on both sides. This unit can also be an independent drive motor unit. Transmission system unit III (wheel-side reducer 100) is mainly an independent gear transmission unit located on the other side of the motor. It achieves a larger transmission ratio, reduces speed and increases torque, transmits smooth torque, can bear greater torque, has a compact structure, is safe and reliable, and meets the reduction ratio requirements of high-horsepower wheel-side reducers.

[0027] The wheel-side reducer 100 includes a first-stage reduction gear, a first planetary gear set, a second planetary gear set, and a third planetary gear set, with the three planetary gear sets connected in series. The first-stage reduction gear includes two pairs of meshing gears, namely a driving gear 3 and a driven gear 4. There are two driving gears 3, which are connected to the two motor sides respectively. The two driving gears 3 mesh with one driven gear 4 to form a power confluence structure, which can meet the requirements of greater power transmission.

[0028] The first, second, and third planetary gear sets all use a sun gear as the input power source, a fixed ring gear, and a planet carrier as the output power source. The three planetary gear sets are connected in series to achieve a larger reduction ratio and a more compact structure. This invention is illustrated with a schematic diagram of the transmission system at this location, which is merely an example. This invention can also perform different gear changes to achieve a transmission ratio that meets the requirements of the entire machine.

[0029] like Figure 3 As shown, according to Figure 3 From a practical perspective: Two brakes 1 are located to the left of the two motors 2 respectively. The right side of the motors 2 is connected to the driving gear 3 of the wheel-side reducer via splines. The input end of the wheel-side reducer consists of two driving gears 3, both with the same number of teeth, Z1. The driven gear 4 has Z2 teeth and is splined to the sun gear 5 of the first planetary gear set. The driven gear 4 is supported by bearings on both sides. The planet gears 6 (3 or 4 are acceptable) in the first planetary gear set are mounted on the planet carrier 8 as idlers. The planet ring gear 7 is braked. The sun gear 5 has Z2 teeth. t1 The number of teeth on planetary gear ring 7 is Z. q1 The sun gear 5 is supported by bearings on both sides. The planet carrier 8 is connected to the sun gear 9 of the second planetary gear set via a spline. The sun gear 9 has Z teeth. t2 The sun gear 9 is supported by bearings on both sides, and the planetary gear ring 11 has Z teeth. q2 In the second planetary gear set, planetary gears 10 (3 or 4 are acceptable) are mounted as idler gears on the planet carrier 12, and the planetary ring gear 11 acts as a brake. The planet carrier 12 is connected to the sun gear 13 of the third planetary gear set via a spline, and the sun gear 13 has Z teeth. t3 The sun gear 13 is supported by bearings on both sides. Planet gears 14 (3 or 4 in total) in the third planetary gear set are mounted as idler gears on the planet carrier 15. The planet carrier 15 outputs power. The planet ring gear 16 has Z teeth. q3 .

[0030] To obtain the set reduction ratio, corresponding calculations are performed based on the transmission structure. Let the number of teeth on the driving gear 3 be Z1 and the number of teeth on the driven gear 4 be Z2. Then, the power transmission ratio of the first-stage gear is... The negative sign indicates that the input and output speeds are in opposite directions.

[0031] According to the principle of planetary arrangement, the formula for arranging the third planet is as follows: In the formula: This refers to the rotational speed of the third sun gear; The rotational speed of the third planetary ring gear is given by the fact that the first, second, and third planetary ring gears are all the same component. And braking; This refers to the rotational speed of the third planetary carrier. The characteristic parameters of the third planetary gear set are given by α3 = Z, where the ratio of the number of teeth on the ring gear to the number of teeth on the third sun gear is Z. q3 / Z t3 Due to planetary ring gear braking, i.e. Therefore, the power transmission ratio of the third planetary gear set is 1 + α3.

[0032] Similarly, according to the principle of planetary arrangement, the formula for the second planetary arrangement is: In the formula: This refers to the rotational speed of the second sun gear; The rotational speed of the planetary ring gear is given by the fact that the first, second, and third planetary ring gears are the same component. And braking; This refers to the rotational speed of the second planetary carrier. The characteristic parameters of the second planetary gear set are given by α2 = Z, where the ratio of the number of teeth on the planetary gear ring to the number of teeth on the second sun gear is Z. q2 / Z t2 Due to planetary ring gear braking, i.e. Therefore, the power transmission ratio of the second planetary gear set is 1 + α2.

[0033] Similarly, according to the principle of planetary arrangement, the formula for the first planetary arrangement is: In the formula: This is the rotational speed of the first sun gear; This refers to the rotational speed of the planetary gear ring. This is the rotational speed of the first planetary carrier; The characteristic parameters of the first planetary gear set are given by α1 = Z, where α1 is the ratio of the number of teeth on the planetary gear ring to the number of teeth on the first sun gear. q1 / Z t1 Due to planetary ring gear braking, i.e. Therefore, the power transmission ratio of the first planetary gear set is 1+α1.

[0034] The total reduction ratio of the left wheel-side reducer is: [-Z2 / Z1]x{[1+(Z q1 / Z t1 )]x[1+(Z q2 / Z t2 )]x[1+(Z q3 / Z t3 )] The negative sign indicates that the input and output speeds are in opposite directions. Z1 represents the number of teeth on the first-stage driving gear 3, Z2 represents the number of teeth on the first-stage driven gear 4, and Z... t1 The number of teeth of the first sun gear 5, Z q1 The number of teeth on planetary gear ring 7, Z q2 The number of teeth on planetary gear ring 12, Z q3 The number of teeth on planetary gear ring 16, Z t2 The number of teeth on the second sun gear 9, Zt3 This refers to the number of teeth on the third sun gear, number 13.

[0035] Brakes can be categorized into spring-type brakes and disc-spring-type brakes. Spring-type brakes are normally open, while disc-spring-type brakes are normally closed. A normally closed brake, when no hydraulic pressure is established, relies on the force of the disc spring to keep the friction pads and outer gear plate closed; once hydraulic pressure is established, the piston pushes the friction pads and outer gear plate apart. A normally open brake, when no hydraulic pressure is established, relies on the force of the spring to keep the friction pads and outer gear plate apart; once hydraulic pressure is established, the piston pushes the friction pads and outer gear plate together.

[0036] Preferably, the brake 300 in this embodiment is a normally closed disc spring brake. Brake locking refers to the closure of the friction pads and outer toothed plate inside the brake; brake unlocking refers to the separation of the friction pads and outer toothed plate. Below the brake housing, there is also an oil temperature sensor that can measure the oil temperature. The sensor's detection end can detect the oil temperature in the brake fluid chamber. When the oil temperature measured by the sensor is higher than the design temperature, the sensor alarms, the vehicle slows down, and the vehicle stops to check whether the overheating is caused by excessive oil volume or other reasons. Simultaneously, the brake 300 is connected to the oil box 500 via the oil pipe 400, which increases the internal space of the chamber and allows excess oil to drain, thus better preventing brake overheating. If the oil volume is excessive, draining the excess oil will allow the vehicle to operate normally; otherwise, the entire brake assembly needs to be replaced for repair. The right end cover of the brake shows a visible oil level line. When the oil level exceeds this line, the drain valve is opened to drain the excess oil.

[0037] The brake contains two oil chambers: one connected to the hydraulic lines, and the other for lubricating the friction plates and splined shaft. These are separated by a highly efficient sealing structure. The brake can also receive an electrical signal from the controller, a signal specific to vehicle movement. Upon energization, an electromagnetic switch opens, establishing oil pressure in the sealed brake chambers. A pressure sensor is mounted on the brake, and a set rated braking pressure value is used. The sensor measures the pressure and compares it to the rated value to determine if replacement or repair is necessary. If the measured braking pressure is lower than the design pressure, an alarm is triggered, and the vehicle slows down. If the measured braking pressure is too high, immediate action is required to investigate the cause of the abnormal pressure. If excessive oil is present in the lubricating chamber, it may indicate excessive leakage, preventing pressure maintenance. In this case, drain the excess oil through the drain box (500mm) to check if the vehicle functions normally. Otherwise, replace the entire brake assembly. Both the oil temperature and pressure sensors are located on the brake housing.

[0038] Preferably, brake 1 uses a high-efficiency sealing structure, such as... Figure 6As shown, it also includes a brake housing 301 with a brake cavity. The brake cavity of the brake housing 301 is sleeved on the spline sleeve 17. In the brake cavity, a friction plate 19, an outer toothed plate 18, and an inner toothed ring 20 that mesh with the outer toothed plate 18 are arranged sequentially from the inside to the outside along the radial direction of the spline sleeve 17. One side of the friction plate 19, the outer toothed plate 18, and the inner toothed ring 20 presses against the pressure plate 21, and the other side has a pressure plate 22. The outer side of the pressure plate 22 presses against the disc spring 23, and the outer side of the disc spring 23 presses against the brake housing 301. The pressure plate 22 is connected to the piston 24 through the retaining ring 25. The piston 24 is sleeved on the outside of the spline sleeve 17 and can extend and retract along the axial direction of the spline sleeve.

[0039] The internal gear ring 20 and disc spring 23 are both fixed to the brake housing 301. The internal gear ring 20 has a circular hole that can accommodate bolts. The internal gear ring 20 and brake housing 301 are fixed to the pressure plate 21 by washers and bolts. The internal gear ring 20, brake housing 301, and pressure plate 21 are also fixedly connected to the transition plate 302 by bolts and washers. The transition plate 302 is fixedly connected to the motor by bolts and washers. In this way, the entire brake is fixedly connected to the motor. The brake housing 301 also has an oil temperature sensor that can detect the oil temperature in the lubrication chamber. It is located at the bottom of the lubrication chamber. By monitoring the temperature in real time, the brake becomes more reliable. At the same time, the brake housing of the brake 16 has a brake oil pressure port. The brake oil pressure port is connected to a pressure sensor that can detect the brake pressure through a pipeline. By monitoring the pressure in real time, the brake becomes more reliable. The brake housing 16 also has a vent plug to keep the pressure inside and outside the lubrication chamber the same as the atmospheric pressure.

[0040] On the left side of the brake housing 301, there is a pressure plate 26 for mounting cylindrical roller bearings. The pressure plate 26 is provided with an oil inlet for connecting to the oil inlet box 500. The oil inlet is connected to the oil inlet box 500 through the oil pipe, and excess oil is discharged through the oil pipe. The oil inlet is connected to the lubricating oil chamber inside the brake.

[0041] like Figure 7 The diagram shows the structure of the wheel-side reducer on one side of the entire machine. On the left side of the vehicle body, there are two independent motors, two independent brakes, and an oil catch box, symmetrically positioned relative to the vehicle body center. The wheel-side reducer on the right side also has two independent motors, two independent brakes, and an oil catch box, symmetrically positioned relative to the vehicle body center. In this diagram, the two motors on the left are referred to as the left motors, symmetrical relative to the vehicle body center, while the motor on the right is referred to as the right motor. Using this diagram as an illustration, a brief explanation of its control logic during vehicle operation will be provided.

[0042] After the vehicle starts, operating the drive lever opens the locking lever, and shifting to neutral unlocks both left and right brakes. If the vehicle is locked in neutral and the engine is turned off, both brakes lock, functioning as parking brakes. When the vehicle moves forward, backward, turns left, or turns right, the power primarily relies on the motor's output, and the brakes only function as parking brakes. The friction pads and polished discs inside the brakes are separated, indicating an unlocked state. Taking a straight line as an example, both motors output the same equal and opposite power, enabling forward and backward movement. When turning left, the left motor cuts off power, and the right motor outputs power, achieving a left turn. Similarly, when turning right, the left motor cuts off power, and the right motor outputs power, achieving a right turn. Furthermore, adjusting the displacement of the left and right motors during turns allows for different output torques, enabling sharp turns, gentle turns, and stationary turns. The single-wheel-side reducer uses a dual-motor drive, which, in addition to providing high braking torque, significantly reduces the space and magnitude of the braking torque required by the brakes, resulting in reliability and a compact structure.

[0043] When not parked, i.e. during steering and braking, the vehicle primarily relies on the motor's displacement to influence the braking torque changes on both sides of the motor, achieving different steering methods. Simultaneously, it monitors brake pressure and brake solenoid valve signals, or brake temperature signals. The vehicle speed is reduced in stages or stopped directly to protect the brakes. Of course, the motor described in this example can also be replaced with an electric motor, relying on the motor's torque cutoff and output to achieve vehicle-related actions.

[0044] This embodiment features a dual-motor wheel-side reducer that works in tandem. The dual-motor configuration can be expanded to include two motors, providing significant braking power. This greatly reduces the space and size required for the brake torque, resulting in improved reliability and a compact structure. The dual-input motors provide power to the final drive assembly and brake respectively. The main drive motors can be two independent devices or integrated as a single input. Besides bulldozers, the dual-motor power system can be extended to other hybrid construction machinery. Furthermore, the brake employs a highly efficient sealing structure and a drainable oil box for enhanced reliability.

[0045] Example 2 An engineering machine, wherein the wheel-side reduction structure described in Embodiment 1 is arranged on the engineering machine.

[0046] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A wheel-side speed reduction structure, characterized in that, It includes a brake, a motor, and a wheel-side reducer arranged in sequence. The brake and the wheel-side reducer are respectively connected to both sides of the motor. Each set of wheel-side reducers is connected to at least two sets of motors. Each set of brakes is connected to an oil collection box through an oil pipe to drain excess oil from the brake. The brake is also equipped with an oil temperature sensor to detect the oil temperature in the brake fluid chamber and a pressure sensor, and the brake pressure is detected by the pressure sensor.

2. The wheel-side reduction structure according to claim 1, characterized in that, The wheel-side reducer includes a first-stage reduction gear, a first planetary gear set, a second planetary gear set, and a third planetary gear set that are sequentially coupled. The first-stage reduction gear includes two pairs of meshing gears, namely a driving gear and a driven gear. There are two driving gears, which are respectively connected to the two motor sides. The two driving gears mesh with one driven gear to form a power confluence structure.

3. The wheel-side reduction structure according to claim 2, characterized in that, The first, second, and third planetary gear sets all have a structure where the sun gear inputs power, the ring gear is fixed, and the planet carrier outputs power; the three planetary gear sets are connected in series.

4. The wheel-side reduction structure according to claim 1, characterized in that, The brake is a normally closed disc spring brake, and the oil temperature sensor and pressure sensor are both arranged on the brake housing.

5. The wheel-side reduction structure according to claim 4, characterized in that, The brake housing is provided with a brake oil pressure port, through which a pressure sensor is connected.

6. The wheel-side reduction structure according to claim 5, characterized in that, The brake has a pressure plate on the side away from the motor, and an oil pipe interface is provided on the pressure plate. An oil pipe is connected through the oil pipe interface, and the oil pipe interface is connected to the lubricating oil chamber inside the brake.

7. The wheel-side reduction structure according to claim 6, characterized in that, The brake housing is provided with a spline sleeve inside, and along the radial direction of the spline sleeve from the inside to the outside are arranged a friction plate that meshes with the outer teeth of the spline sleeve, an outer tooth plate, and an inner tooth ring that meshes with the outer tooth plate.

8. The wheel-side reduction structure according to claim 7, characterized in that, The brake is fixedly connected to the motor via a transition plate.

9. The wheel-side reduction structure according to claim 1, characterized in that, The wheel-side reducer is driven by two motors.

10. An engineering machinery, characterized in that, The engineering machinery is equipped with a wheel-side speed reduction structure as described in any one of claims 1-9.

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