A high-power oil fracturing vehicle transmission system

Abstract

The application discloses a high-power oil fracturing vehicle transmission system, which comprises a torque converter and a gearbox integrated together, wherein the gearbox is provided with a fixed shaft and a planetary structure; the torque converter comprises a shell a, the shell a is provided with a torque conversion mechanism, and the torque conversion mechanism is connected with an input assembly; the gearbox comprises a shell b, the shell b is fixedly connected with the shell a, the shell b is provided with a parallel shaft transmission system which is in transmission connection with an output end of the torque conversion mechanism and a planetary wheel transmission system which is in transmission connection with an output end of the parallel shaft transmission system, and an output assembly is connected with the output end of the planetary wheel transmission system; the gear position of the parallel shaft transmission system is provided with three gears, the gear position of the planetary wheel transmission system is provided with three gears, and the cross combination is provided with nine gears. The advantages of the fixed shaft transmission and the planetary transmission are combined, balance is achieved, the weight is reduced, the transmission torque is improved, the integration of the torque converter and the gearbox reduces the overall volume and saves the installation space.

Description

Technical Field

[0001] This invention relates to the field of transmission system technology, and specifically to a high-power transmission system for an oil fracturing truck. Background Technology

[0002] Oil fracturing trucks are heavy equipment used for liquid fracturing operations, mainly in oil and gas extraction. They inject liquid into wells under high pressure to fracture rock layers and release oil and gas.

[0003] In oil fracturing vehicles, a diesel engine drives a transmission system to power the fracturing pump for fracturing operations. Fracturing operations require high reliability for the entire system. There are three main technical approaches to fracturing transmission systems: First, a separate structure where the torque converter and gearbox are separate and connected by a driveshaft; second, an integrated structure where the torque converter and gearbox are combined, with the torque converter directly mounted on the engine flywheel via a flexible disc; and third, eliminating the torque converter and only having a gearbox. The third approach, due to its complex operating conditions and control, has been abandoned by the market due to issues like friction plate burnout. Currently, the mainstream solutions are the first and second approaches. The second approach uses a planetary gear arrangement, typically with 7 or 8 gears, which is lightweight and compact, but frequently experiences shaft breakage and friction plate burnout, resulting in low reliability. The first approach offers the highest reliability and is the most widely accepted by customers. However, the first option is a split arrangement, which requires an additional drive shaft between the torque converter and the gearbox, resulting in a long axial dimension and heavy weight. Since fracturing trucks have certain requirements for vehicle length and weight for road use, there are requirements to reduce the weight and axial dimension of the gearbox.

[0004] Furthermore, in conventional gearboxes, parallel shaft drives or planetary gear drives are typically used independently. While parallel shaft drives offer higher reliability, they are heavy and large in size, making it difficult to achieve coaxial output. Additionally, the long shaft length increases machining difficulty and shaft deflection, affecting reliability. On the other hand, planetary gear drives are lighter, but they have lower torque transmission capacity and smaller shaft diameters, leading to shaft breakage and thus lower reliability.

[0005] In particular, new energy oil fracturing trucks are driven by electric motors. Due to the characteristics of electric motors, their torque is greater than that of traditional fuel-fired fracturing trucks at low speeds. When using independent planetary gear transmission, the shaft that transmits the torque cannot fully bear the output torque of the motor, resulting in a high risk of shaft breakage.

[0006] In summary, the following problems were identified during the fracturing process along the three routes: 1) friction plate burnout; 2) shaft breakage; 3) inability to engage gears. A more reliable gearbox for oil fracturing trucks, suitable for both conventional and new energy power sources, needs to be developed. Summary of the Invention

[0007] To address the shortcomings of the existing technology, this invention proposes a high-power oil fracturing truck transmission system.

[0008] To achieve the above-mentioned technical effects, the present invention adopts the following solution:

[0009] A high-power oil fracturing truck transmission system includes an integrated torque converter and gearbox, wherein the gearbox adopts a fixed-shaft + planetary structure.

[0010] The torque converter includes a housing a and a torque converter mechanism disposed within the housing a, the torque converter mechanism being connected to the input component;

[0011] The gearbox includes a housing b, which is fixedly connected to housing a. The housing b contains a parallel shaft transmission system that is connected to the output end of the torque converter and a planetary gear transmission system that is connected to the output end of the parallel shaft transmission system. The output end of the planetary gear transmission system is connected to the output assembly.

[0012] The parallel shaft transmission system has three gears via three clutches, and the planetary gear transmission system has three gears via three clutches. The three clutches of the parallel shaft transmission system and the three clutches of the planetary gear transmission system are cross-engaged to form nine gears, and the speed ratios are set to 4.835~4.154~3.571~2.603~2.237~1.923~1.354~1.163~1.

[0013] In a preferred embodiment, the parallel shaft transmission system includes a main shaft, a side shaft m, and a side shaft n rotatably disposed within a housing b. The side shafts m and n are located on the side of the main shaft. The output end of the torque converter is provided with a Z1 transmission gear. The main shaft is connected to the Z1 transmission gear via a K1 clutch. A Z5 engagement gear and a Z7 engagement gear are fixedly disposed on the main shaft. The side shafts m and n are respectively connected to the Z1 transmission gear via fixed Z2 and Z3 engagement gears. A Z4 transmission gear and a Z6 transmission gear are also rotatably disposed on the side shafts m and n respectively. The side shaft m is connected to the Z4 transmission gear via a K2 clutch, and the side shaft n is connected to the Z6 transmission gear via a K3 clutch. The Z4 and Z6 transmission gears are respectively connected to the Z5 engagement gear and the Z7 engagement gear. The planetary gear transmission system is connected to the main shaft.

[0014] In a preferred embodiment, the planetary gear transmission system includes a transmission shaft L fixedly connected to the main shaft. A primary sun gear and a secondary sun gear are fixedly mounted on the transmission shaft L. A primary ring gear is connected to the periphery of the primary sun gear via several primary planet gears. The primary ring gear is connected to the housing b via a K5 clutch. A secondary ring gear is connected to the periphery of the secondary sun gear via several secondary planet gears. The secondary ring gear is connected to the housing b via a K4 clutch. A K6 clutch is also mounted on the transmission shaft L. The K6 clutch is connected to several primary planet gears via a primary planet carrier. The primary planet carrier is connected to the secondary ring gear via a Z13 connecting gear. The several secondary planet gears are connected to the output assembly via the secondary planet carrier.

[0015] In the preferred technical solution, the K1, K2, K3, K6, K5, and K4 clutches operate on the same principle, including a fixed inner hub and a piston seat. The inner hub and piston seat are spaced apart, and a movable piston is located between them. A movable outer hub is fitted around the outer side of the inner hub. The inner hub has several sliding friction plates, and the outer hub has several sliding steel plates. The friction plates and steel plates are arranged alternately. An oil chamber is located on the side of the piston seat facing the inner hub. A portion of the piston is embedded in the oil chamber and slidably sealed. The oil chamber is connected to a pressure oil passage, and the piston is connected to an elastic reset element.

[0016] In a preferred embodiment, the piston seat is provided with a quick-release valve, and the piston seat has a connecting channel. Oil holes a, b, and c are sequentially arranged on the connecting channel. Oil hole a connects to the housing body. The quick-release valve is located within the connecting channel. Oil holes b and c connect to the oil chamber. The connecting channel is connected to an oil inlet hole located between oil holes a and b, and the oil inlet hole is connected to a pressure oil passage. The quick-release valve includes a second spring and a valve core located within the connecting channel. The valve core is matched to the connecting channel and is pushed and slid by the second spring.

[0017] In a preferred embodiment, the elastic reset member includes a fixed spring plate located between the piston and the inner hub, and the spring plate is connected to the piston via a first spring.

[0018] In a preferred embodiment, the torque converter includes a drive shaft b, a cover wheel, a pump wheel, a turbine, and a guide wheel. The pump wheel is connected to the input component via the cover wheel. The pump wheel, turbine, and guide wheel are mounted on the drive shaft b. The drive shaft b is rotatably disposed within the housing a, and a parallel shaft transmission system is connected to the drive shaft b. The turbine is fixedly connected to the drive shaft b. The guide wheel is disposed between the pump wheel and the turbine, and a locking clutch is also provided between the pump wheel and the turbine.

[0019] In a preferred embodiment, the torque converter is connected to a power take-off mechanism, which includes a drive gear fixed on the pump wheel. The drive gear is connected to a pump gear via a rotatable power take-off gear located inside the housing a. The pump gear is connected to a return oil pump, which is located on the housing a.

[0020] A preferred technical solution further includes a lubrication system, which includes a main oil valve and several secondary oil valves disposed on housing a and housing b. The main oil valve is connected to an oil supply pipe, and the main oil valve is connected to several secondary oil valves through several branch oil pipes. The several secondary oil valves are independently connected to various lubrication components through lubrication oil pipes, and the lubrication oil pipes are built into housing a and housing b.

[0021] Compared with existing technologies, the beneficial effects are:

[0022] 1. In this invention, the torque converter and the gearbox are combined into an integrated unit, thereby reducing the overall size, saving installation space, and avoiding burning of the friction plates.

[0023] 2. In this invention, a parallel shaft drive system and a planetary gear drive system are combined for power transmission within the gearbox. In the parallel shaft drive system, the shaft size can be increased, thereby reducing the risk of shaft failure. The parallel shaft drive system has a small speed ratio difference, and the torque transmission capacity between each gear is relatively consistent, achieving excellent uniformity and minimizing shift shock. The weight of each gear is also more uniform. In the planetary gear drive system, the speed ratio is larger, and multiple planetary gears can reduce the weight of each gear while ensuring coaxial output. Therefore, this invention combines the advantages of fixed-axis transmission and planetary transmission, achieving a balance that provides high reliability while reducing weight and increasing transmitted torque. Furthermore, the torque is directly connected to the torque converter via the parallel shaft drive system, and the transmitted torque is buffered before being transmitted to the planetary gear drive system, thus preventing shaft breakage in the planetary gear drive system.

[0024] 3. The speed ratio setting of the present invention has a small difference in the speed ratio between two adjacent gears, which makes shifting smoother, less impactful, easier to engage, and improves reliability.

[0025] 4. In this invention, the first gear has a large speed ratio, which enables the transmission of higher torque. When multiple fracturing trucks are running in parallel, the high speed ratio allows the fracturing trucks to run in parallel at high speed.

[0026] 5. In this invention, by setting a fast-release valve, the transient response capability is improved, enabling faster gear shifting and quick response. Attached Figure Description

[0027] Figure 1 This is a simplified schematic diagram of the present invention.

[0028] Figure 2 This is a schematic diagram of the parallel shaft transmission system structure in this invention.

[0029] Figure 3 This is a cross-sectional schematic diagram of the spindle in this invention.

[0030] Figure 4 This is a cross-sectional schematic diagram of the side axis m in this invention.

[0031] Figure 5 This is a schematic diagram of the planetary gear transmission system in this invention from one perspective.

[0032] Figure 6 This is another perspective structural diagram of the planetary gear transmission system in this invention.

[0033] Figure 7 This is a cross-sectional schematic diagram of the K6 clutch in this invention.

[0034] Reference numerals: 1. Torque converter; 2. Gearbox; 3. Pump impeller; 4. Turbine; 5. Guide wheel; 6. Input shaft; 7. Flywheel; 8. Main shaft; 9. Z1 transmission gear; 10. K1 clutch; 11. Side shaft m; 12. Z2 connecting gear; 13. Z4 transmission gear; 14. K2 clutch; 15. Side shaft n; 16. Z3 connecting gear; 17. Z6 transmission gear; 18. Z5 engagement gear; 19. Z7 engagement gear; 20. Drive shaft L; 21. K6 clutch; 22. K5 clutch; 23. K4 clutch; 24. First-stage sun gear; 25. First-stage planetary gears; 26. 27. First-stage planetary carrier; 28. Second-stage sun gear; 29. ​​Second-stage planetary gear; 30. Second-stage planetary carrier; 31. Output assembly; 32. First-stage ring gear; 33. Second-stage ring gear; 34. K3 clutch; 35. Inner hub; 36. Piston seat; 37. Outer hub; 38. Friction plate; 39. Steel plate; 40. Piston; 41. First spring; 42. Spring pressure plate; 43. Second spring; 44. Valve core; 45. Oil chamber; 46. Connecting channel; 47. Quick release valve; 48. Oil hole b; 49. Oil hole a; 50. Oil hole c; 51. Drive gear; 52. Power take-off gear; 53. Pump gear; 54. Return oil pump. Detailed Implementation

[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0036] A high-power oil fracturing truck transmission system includes an integrated torque converter 1 and a gearbox 2.

[0037] By combining the torque converter 1 with the gearbox 2 into a single integrated unit, the overall size is reduced, installation space is saved, and the torque converter mechanism prevents the friction plates from burning out.

[0038] The torque converter 1 includes a housing a, and a torque converter mechanism is provided inside the housing a. The torque converter mechanism is connected to an input component; the input component is the flywheel 7 of the engine.

[0039] The gearbox 2 adopts a fixed-axis + planetary structure, that is, the gearbox 2 includes a housing b, which is fixedly connected to the housing a. The housing b is provided with a parallel shaft transmission system and a planetary gear transmission system. The parallel shaft transmission system is connected to the output end of the torque converter, and the planetary gear transmission system is connected to the output end of the parallel shaft transmission system. The output end of the planetary gear transmission system is connected to the output component 30, which is the output shaft.

[0040] The parallel shaft drive system and the planetary gear drive system are combined for power transmission within the gearbox 2. In the parallel shaft drive system, the shaft can be enlarged, thereby reducing the risk of shaft failure. The parallel shaft drive system has a small speed ratio difference, and the torque transmission capacity between each gear is relatively consistent, achieving extreme uniformity and ensuring minimal shift shock. The weight of each gear is also relatively uniform. In the planetary gear drive system, the speed ratio is relatively large, and multiple planetary gears can reduce the weight of each gear while ensuring coaxial output. Therefore, this invention combines the advantages of fixed-axis transmission and planetary transmission, achieving a balance that provides high reliability while reducing weight and increasing transmitted torque. Furthermore, the torque is directly connected to the torque converter through the parallel shaft drive system, and the transmitted torque is buffered before being transmitted to the planetary gear drive system, thus preventing shaft breakage in the planetary gear drive system.

[0041] The parallel shaft transmission system has three gears via three clutches, and the planetary gear transmission system has three gears via three clutches. The three clutches of the parallel shaft transmission system and the three clutches of the planetary gear transmission system are cross-engaged to form nine gears. The gear ratios from the first to the ninth gear are set as follows: 4.835~4.154~3.571~2.603~2.237~1.923~1.354~1.163~1.

[0042] The small difference in gear ratio between two adjacent gears results in smoother shifting, less impact, easier gear engagement, and improved reliability. In addition, the large gear ratio of the first gear enables the transmission of higher torque. When multiple fracturing trucks are running side by side, the high-speed ratio allows the fracturing trucks to run side by side at high speeds.

[0043] In a preferred embodiment, the parallel shaft transmission system includes a main shaft 8, a side shaft m11, and a side shaft n15 rotatably disposed within a housing b. The side shafts m11 and n15 are parallel to each other on the side of the main shaft 8. The output end of the torque converter is equipped with a Z1 transmission gear 9. The main shaft 8 is connected to the Z1 transmission gear 9 via a K1 clutch 10. Two gears, Z5 and Z7, with different numbers of teeth, are fixedly mounted on the main shaft 8. The side shafts m11 and n15 are respectively connected by a fixed Z2 connecting gear 1. 2. The Z3 connecting gear 16 is connected to the Z1 transmission gear 9. The side shaft m11 and the side shaft n15 are respectively rotatably provided with the Z4 transmission gear 13 and the Z6 transmission gear 17. The side shaft m11 is connected to the Z4 transmission gear 13 through the K2 clutch 14. The side shaft n15 is connected to the Z6 transmission gear 17 through the K3 clutch 33. The Z4 transmission gear 13 and the Z6 transmission gear 17 are respectively connected to the Z5 engagement gear 18 and the Z7 engagement gear 19. The planetary gear transmission system is connected to the main shaft 8.

[0044] When clutch 10 K1 is closed, it directly connects transmission gear 9 Z1 to main shaft 8, transmitting the output torque of torque converter to main shaft 8, and then to planetary gear transmission system.

[0045] When clutch K2 14 is closed, transmission gear Z1 9 transmits the output torque of the torque converter to the side shaft m11 through connecting gear Z2 12, and then to transmission gear Z4 13 through clutch K2 14. Since transmission gear Z4 13 is connected to meshing gear a, the torque is transmitted to the main shaft 8 and then to the planetary gear transmission system.

[0046] When clutch K3 33 is closed, transmission gear Z1 transmits the output torque of the torque converter to the side shaft n15 through connecting gear Z3 16, and then to transmission gear Z6 17 through clutch K3 33. Since transmission gear Z6 17 is connected to meshing gear b, the torque is transmitted to the main shaft 8 and then to the planetary gear transmission system.

[0047] In a preferred embodiment, the planetary gear transmission system includes a transmission shaft L20 fixedly connected to the main shaft 8. A primary sun gear 24 and a secondary sun gear 27 are fixedly mounted on the transmission shaft L20. A primary ring gear 31 is connected to the periphery of the primary sun gear 24 via a plurality of primary planet gears 25. The primary ring gear 31 is connected to the housing b via a K5 clutch 22. A secondary ring gear 32 is connected to the periphery of the secondary sun gear 27 via a plurality of secondary planet gears 28. The secondary ring gear 32 is connected to the housing b via a K4 clutch 23. A K6 clutch 21 is also mounted on the transmission shaft L20. The K6 clutch 21 is connected to the plurality of primary planet gears 25 via a primary planet carrier 26. The primary planet carrier 26 is connected to the secondary ring gear 32 via a Z13 connecting gear. The rotation center of the Z13 connecting gear coincides with the rotation center of the transmission shaft L20. The plurality of secondary planet gears 28 are connected to the output assembly 30 via a secondary planet carrier 29.

[0048] In a preferred embodiment, the design principle of the planetary mechanism is: number of sun gear teeth + number of ring gear teeth / number of planet gears = integer and / or number of sun gear teeth + 2 times the number of planet gear teeth = number of ring gear teeth.

[0049] In the preferred technical solution, the K1 clutch 10, K2 clutch 14, K3 clutch 33, K6 clutch 21, K5 clutch 22, and K4 clutch 23 operate on the same principle, including a fixed inner hub 34 and a piston seat 35. The inner hub 34 and piston seat 35 are spaced apart, and a movable piston 39 is provided between the inner hub 34 and piston seat 35. The piston 39 moves along the line connecting the inner hub 34 and piston seat 35. A movable outer hub 36 is fitted around the outer side of the inner hub 34. The inner hub 34 is provided with several sliding friction plates 37, and the outer hub 36 is provided with several sliding steel plates 38. The friction plates 37 and steel plates 38 are arranged alternately. An oil cavity is provided on the side of the piston seat 35 facing the inner hub 34. A portion of the piston 39 is embedded in the oil cavity and slidably sealed. The piston 39 is provided with inner and outer sealing rings. The oil cavity is connected to a pressure oil passage. An elastic reset member is connected to the piston 39 for resetting after the piston 39 has moved. The pressure oil passage is built into the shaft. Hydraulic oil is injected into the oil chamber through the pressure oil passage and fills the space between the piston seat and the piston 39. The oil pressure of the pressure oil pushes the piston 39 to move toward the inner hub 34, pressing several friction plates 37 and several steel plates 38. The friction plates 37 and several steel plates 38 are locked together by friction, thereby driving the outer hub 36 to rotate and transmitting power through the outer hub 36.

[0050] Both the friction plates 37 and the steel plates 38 are arranged in annular shape. The inner hub 34 has a protruding part facing the piston seat 35. Several friction plates 37 are fitted onto the protruding part of the inner hub 34. At least two sliding locking parts a protrude from the inner side of the friction plates 37. The protruding part of the inner hub 34 has a groove a that matches the sliding locking parts a. At least two sliding locking parts a are respectively inserted into the corresponding groove a and slide, thereby restricting the friction plates 37 on the inner hub along the line connecting the inner hub and the piston seat. The steel plate slides along the outer hub 36 without rotating; the outer hub is arranged in a ring around the inner hub 34, the outer edge of the steel plate is attached to the inner side of the outer hub 36, the protruding part of the inner hub 34 passes through the middle of the steel plate, and at least two sliding locking parts b protrude from the outer edge of the steel plate. The inner side of the outer hub 36 is provided with a sliding groove b that matches the sliding locking parts. At least two sliding locking parts b are respectively embedded in the corresponding sliding groove b and slide, thereby restricting the steel plate 38 to slide along the line connecting the inner hub and the piston seat on the outer hub 36 without rotating.

[0051] In the K1 clutch 10, the inner hub 34 and piston seat 35 are fixed on the main shaft 8, and the piston seat 35 is set against the inner side of the Z1 transmission gear 9. The outer hub 36 is connected to the Z1 transmission gear 9, so that when the K1 clutch 10 is closed, the rotation of the Z1 transmission gear 9 is transmitted through the outer hub 36 to the inner hub 34 and piston seat 35, driving the main shaft 8 to rotate.

[0052] In this configuration, the inner hub 34 and piston seat 35 of clutches K2 and K3 are fixed to the side shafts m11 and n15, respectively, and the outer hub 36 is fixedly connected to the Z1 transmission gear 9 and the Z4 transmission gear 13. Thus, the rotation of the side shafts m11 and n15 is transmitted to the Z1 transmission gear 9 and the Z4 transmission gear 13 through the closing of clutches K2 and K3 respectively.

[0053] Specifically, for clutch K6 21, inner hub 34 and piston seat 35 are fixed to drive shaft L20, and outer hub 36 is fixedly connected to first-stage planetary carrier 26, thereby transmitting the rotation of drive shaft L20 to first-stage planetary carrier 26 through the closing of clutch K6 21.

[0054] In the case of clutches K5 and K4, the inner hub 34 and piston seat 35 are fixedly sleeved on the first-stage gear ring 31 and the second-stage gear ring 32, and the outer hub 36 is fixedly connected to the housing b, so that the first-stage gear ring 31 and the second-stage gear ring 32 can be fixed when clutches K5 and K4 are closed.

[0055] In a preferred embodiment, the piston seat 35 is provided with a quick-release valve 46, and the piston seat 35 is provided with a connecting channel 45. The connecting channel 45 is provided with oil holes a49, b48, and c47 in sequence. Oil hole a49 is connected to an oil drain pipe provided in the housing b. The quick-release valve 46 is provided in the connecting channel to open and close the channel for pressure oil inlet and outlet. Oil holes b48 and c47 are connected to the oil chamber 44, and the diameter of oil hole b48 is larger than the diameter of oil hole c47. The connecting channel 45 is also connected to an oil inlet, which is located between oil holes a49 and b48. The oil inlet is connected to a pressure oil passage, and hydraulic oil is injected into the connecting channel through the pressure oil passage and then from the oil inlet. In the first stroke, the hydraulic oil in the connecting channel first enters the oil chamber 44 through the oil hole b48, quickly pushing the piston to move towards the friction plate 37 and the steel plate 38. The quick-release valve 46 includes a second spring 42 and a valve core 43 located in the connecting channel 45. The valve core 43 is matched with the connecting channel and is pushed and slid by the second spring. There are two valve cores and two second springs. The valve cores are matched with the connecting channel and can move like pistons in the connecting channel. The two valve cores correspond to the oil hole a and the oil hole c, respectively. In the natural state, the valve core corresponding to the oil hole a is located near the oil hole a but does not block the oil hole a. The valve core corresponding to the oil hole c blocks the oil hole c. One end of each of the two second springs is connected to the two valve cores, and the other end is fixed in the connecting channel. When the pressure of the hydraulic oil in the connecting channel can overcome the spring force, it will push the valve core to move in the direction of compressing the spring. In the first stroke, the oil pressure in the connecting channel pushes one of the valve cores to move towards oil hole a, thereby blocking oil hole a and preventing the hydraulic oil in the oil chamber from being discharged from oil hole a, thus establishing a stable pressure in the oil chamber. In the second stroke, the pressure in the connecting channel pushes another valve core corresponding to oil hole c to move, thereby opening oil hole c, allowing the hydraulic oil in the connecting channel to enter the oil chamber 44 simultaneously through oil hole b48 and oil hole c47. At this time, oil hole a49 is sealed by valve core 43, and pressure is established in the oil chamber. When the pressure in the oil passage is released, valve core 43 resets, oil hole a opens, and the oil in the piston chamber is directly discharged into the housing a, and discharged through the drain pipe in the housing a, thus accelerating the discharge speed of the hydraulic oil.

[0056] By opening the quick-release valve 46, hydraulic oil can simultaneously enter and exit the oil chamber 44 through oil hole b49 and oil hole c49, increasing the hydraulic oil flow rate. This allows for faster movement of the piston 39, improving transient response and enabling quicker gear shifts and a more rapid response. Compared to a conventional clutch, by setting the quick-release valve 46, the shift time is controlled to within 0.8 seconds, while reducing the pressure build-up time in the first stroke. After the first stroke pressure build-up, the pressure rapidly rises to the second stroke pressure build-up, which is approximately 1.0-1.2 MPa, ensuring the friction plates are properly compressed. The second stroke pressure build-up time is approximately 300-400 ms, significantly reducing the impact during friction plate engagement, reducing slippage, decreasing the likelihood of friction plate burnout, and improving friction plate reliability. Furthermore, with the quick-release valve 46, the clutch response speed is 15 times faster, and the speed at which full torque is reached is 10 times faster, greatly improving the transmission efficiency of the transmission system.

[0057] In a preferred embodiment, the elastic reset member includes a fixed spring plate 41, which is located between the piston 39 and the inner hub, and is connected to the piston 39 by a first spring 40.

[0058] In a preferred embodiment, the torque converter includes a drive shaft b, a guide disc, a flexible disc, a cover wheel, a pump wheel 3, a turbine 4, and a guide wheel 5. The cover wheel is connected to the input component via the flexible disc. The guide disc is located inside the housing a. The pump wheel 3 is connected to the guide disc and is fixedly connected to the cover wheel. The pump wheel 3, the turbine, and the guide wheel 5 are all mounted on the drive shaft b. The drive shaft b is rotatably mounted inside the housing a, and a parallel shaft transmission system is connected to the drive shaft b. The turbine 4 is positioned relative to the pump wheel 3 and is fixedly connected to the drive shaft b. The guide wheel 5 is located between the pump wheel 3 and the turbine.

[0059] A lock-up clutch is also provided between the pump wheel 3 and the turbine. In the attached figure, the lock-up clutch is the K7 clutch. After the gearbox 2 completes the shift, the torque converter is required to enter the lock-up state from the unlocked state. Before locking, the engine speed is increased. Under the same torque, the common input point is moved to the high transmission ratio input point of the torque converter. When the lock-up clutch is engaged, the speed difference during locking is reduced, and the impact is reduced. When the input speed of the gearbox 2 is >1250 rpm, the lock-up clutch is engaged.

[0060] In a preferred embodiment, the torque converter is connected to a power take-off mechanism, which includes a drive gear 50 fixedly mounted on the pump wheel 3. The drive gear 50 is connected to a pump gear 52 rotatably mounted on a power take-off gear 51 within the housing a. The pump gear 52 is connected to a return oil pump 53, which is mounted on the housing a.

[0061] When the pump wheel 3 rotates, it can drive the pump gear 52 to rotate through the drive gear 50 and the power take-off gear 51, thereby driving the return oil pump 53 to run, thus providing power for the circulation of lubricating oil and / or discharging the internal leakage oil in the hydraulic torque converter to the outside of the oil tank.

[0062] A preferred technical solution further includes a lubrication system, which includes a main oil valve and several secondary oil valves disposed on housing a and housing b. The main oil valve is connected to an oil supply pipe, and the main oil valve is connected to several secondary oil valves through several branch oil pipes. The several secondary oil valves are independently connected to various lubrication components through lubrication oil pipes. The lubrication oil pipes are built into housing a and housing b. The specific structure adopts existing technology, such as the "An Oil Circuit Arrangement Structure for a Power Shift Transmission" with announcement number "CN213017591U".

[0063] By incorporating the lubricating oil pipes internally, the number of pipes on the surfaces of housing a and housing b is reduced, resulting in a cleaner surface and preventing external pipes from being damaged and leaking oil upon impact.

[0064] In this invention, clutches K1, K2, K3, K6, K5, K7, and K4 are all driven by hydraulic oil pressure, and the injection of hydraulic oil is controlled by a solenoid valve.

[0065] The shifting logic of this invention is as follows:

[0066] First gear: With clutches K1 10 and K4 23 engaged, engine power is transmitted to transmission gear Z1 9 via the torque converter. Since clutch K1 10 is engaged, power is directly transmitted to the main shaft 8. From the main shaft 8, power then travels through transmission shaft L20, driving the first-stage sun gear 24 and second-stage sun gear 27 to rotate. Clutch K4 23 is engaged, fixing the second-stage ring gear 32 to the housing b. This causes multiple second-stage planetary gears 28 to rotate and revolve within the second-stage ring gear 32, driving the second-stage planetary carrier 29 to rotate, thus transmitting power to the output assembly 30. Simultaneously, although the first-stage sun gear 24 drives the first-stage planetary gears 25 and first-stage planetary carrier 26 to rotate, the fixed position of the second-stage ring gear 32 to the housing b blocks the transmission of planetary carrier rotation, thus not affecting the rotation of the second-stage planetary gears 28 and the first-stage planetary carrier 29.

[0067] Second gear: With clutches K3 33 and K4 23 engaged, engine power is transmitted to transmission gear Z1 9 via the torque converter. Transmission gear Z1 9 drives the side shaft m11 to rotate via connecting gear Z2 12. Since clutch K3 33 is engaged, transmission gear Z4 13 is also engaged. Through engagement gear Z5 18, which meshes with transmission gear Z4 13, power is transmitted to the main shaft 8. From the main shaft 8, power is transmitted through transmission shaft L20 to the first-stage sun gear 24 and second-stage sun gear 27. With clutch K4 23 engaged, the second-stage ring gear 32 is fixed to the housing b. Multiple second-stage planetary gears 28 rotate and revolve within the second-stage ring gear 32, driving the second-stage planetary carrier 29 to rotate, thus transmitting power to the output assembly 30. Simultaneously, although the first-stage sun gear 24 drives the first-stage planetary gears 25 and first-stage planetary carrier 26, the fixed connection between the second-stage ring gear 32 and housing b prevents the transmission of planetary carrier rotation, thus not affecting the rotation of the second-stage planetary gears 28 and the first-stage planetary carrier 29.

[0068] In third gear: with clutches K2 14 and K4 23 engaged, the engine power is transmitted to transmission gear Z1 9 via the torque converter. Transmission gear Z1 9 drives the side shaft n15 to rotate via connecting gear Z3 16. Since clutch K2 14 is engaged, transmission gear Z6 17 rotates. Through engagement gear Z7 19, which meshes with transmission gear Z6 17, power is transmitted to the main shaft 8. From the main shaft 8, power is transmitted to the first-stage sun gear 24 and second-stage sun gear 27 via transmission shaft L20. With clutch K4 23 engaged, the second-stage ring gear 32 is fixed to the housing b. Multiple second-stage planetary gears 28 rotate and revolve within the second-stage ring gear 32, driving the second-stage planetary carrier 29 to rotate, thus transmitting power to the output assembly 30. Simultaneously, although the first-stage sun gear 24 drives the first-stage planetary gears 25 and first-stage planetary carrier 26, the fixed connection between the second-stage ring gear 32 and housing b prevents the transmission of planetary carrier rotation, thus not affecting the rotation of the second-stage planetary gears 28 and the first-stage planetary carrier 29.

[0069] Fourth gear: With clutches K1 10 and K5 22 engaged, the engine power is transmitted to transmission gear Z1 9 via the torque converter. Since clutch K1 10 is engaged, the power is directly transmitted to the main shaft 8. After passing through the main shaft 8, the power is then transmitted through the transmission shaft L20 to drive the first-stage sun gear 24 and the second-stage sun gear 27 to rotate. The second-stage sun gear 27 drives multiple second-stage planetary gears 28 to rotate. At the same time, since clutch K5 22 is engaged, the first-stage ring gear 31 is fixed to the housing b. Multiple first-stage planetary gears 25 rotate and revolve within the first-stage ring gear 31, driving the first-stage planetary carrier 26 to rotate. This, in turn, drives the first-stage ring gear 31 to rotate via the connecting gear Z13, further driving multiple second-stage planetary gears 28 to rotate, which in turn drives the second-stage planetary carrier 29 to rotate, transmitting the power to the output assembly 30.

[0070] Fifth gear: With clutches K3 33 and K5 22 engaged, the engine power is transmitted to transmission gear Z1 9 via the torque converter. Transmission gear Z1 9 drives the side shaft m11 to rotate via connecting gear Z2 12. Since clutch K3 33 is engaged, transmission gear Z4 13 is driven to rotate. Through engagement gear Z5 18, which meshes with transmission gear Z4 13, the power is transmitted to the main shaft 8. After passing through the main shaft 8, the power is transmitted to the first-stage sun gear 24 and second-stage sun gear 27 via transmission shaft L20. Second-stage sun gear 27 drives multiple second-stage planetary gears 28 to rotate. At the same time, with clutch K5 22 engaged, the first-stage ring gear 31 is fixed to the housing b. Multiple first-stage planetary gears 25 rotate and revolve within the first-stage ring gear 31, driving the first-stage planetary carrier 26 to rotate. This, in turn, drives the first-stage ring gear 31 to rotate via connecting gear Z13, further driving multiple second-stage planetary gears 28 to rotate, which in turn drives the second-stage planetary carrier 29 to rotate, transmitting the power to the output assembly 30.

[0071] Sixth gear: With clutches K2 14 and K5 22 engaged, the engine power is transmitted to transmission gear Z1 9 via the torque converter. Transmission gear Z1 9 drives the side shaft n15 to rotate via connecting gear Z3 16. Since clutch K2 14 is engaged, transmission gear Z6 17 is driven to rotate. Through engagement gear Z7 19, which meshes with transmission gear Z6 17, the power is transmitted to the main shaft 8. After passing through the main shaft 8, the power is transmitted to the first-stage sun gear 24 and second-stage sun gear 27 via transmission shaft L20. Second-stage sun gear 27 drives multiple second-stage planetary gears 28 to rotate. At the same time, with clutch K5 22 engaged, the first-stage ring gear 31 is fixed to the housing b. Multiple first-stage planetary gears 25 rotate and revolve within the first-stage ring gear 31, driving the first-stage planetary carrier 26 to rotate. This, in turn, drives the first-stage ring gear 31 to rotate via connecting gear Z13, further driving multiple second-stage planetary gears 28 to rotate, which in turn drives the second-stage planetary carrier 29 to rotate, transmitting the power to the output assembly 30.

[0072] Seventh gear: When clutches K1 10 and K6 21 are engaged, the engine power is transmitted to transmission gear Z1 9 via the torque converter. Since clutch K1 10 is engaged, the power is directly transmitted to the main shaft 8. After passing through the main shaft 8, the power is transmitted through the transmission shaft L20 to drive the first-stage sun gear 24 and the second-stage sun gear 27 to rotate. The second-stage sun gear 27 drives multiple second-stage planetary gears 28 to rotate. At the same time, since clutch K6 21 is engaged, the first-stage planetary carrier 26 is directly driven to rotate through the transmission shaft L20, which in turn drives the second-stage ring gear 32 to rotate, further driving multiple second-stage planetary gears 28 to rotate. Thus, the power is transmitted to the output assembly 30 through the second-stage planetary carrier 29.

[0073] Eighth gear: With clutches K3 33 and K6 21 engaged, the engine power is transmitted to transmission gear Z1 9 via the torque converter. Transmission gear Z1 9 drives the side shaft m11 to rotate via connecting gear Z2 12. Since clutch K3 33 is engaged, transmission gear Z4 13 is driven to rotate. Through engagement gear Z5 18, which meshes with transmission gear Z4 13, the power is transmitted to the main shaft 8. After passing through the main shaft 8, the power is transmitted to the first-stage sun gear 24 and second-stage sun gear 27 via transmission shaft L20. Second-stage sun gear 27 drives multiple second-stage planetary gears 28 to rotate. At the same time, since clutch K6 21 is engaged, transmission shaft L20 directly drives the first-stage planetary carrier 26 to rotate, thereby driving the second-stage ring gear 32 to rotate, further driving multiple second-stage planetary gears 28 to rotate. Thus, the power is transmitted to the output assembly 30 via the second-stage planetary carrier 29.

[0074] Ninth gear: With clutches K2 14 and K6 21 engaged, the engine power is transmitted to transmission gear Z1 9 via the torque converter. Transmission gear Z1 9 drives the side shaft n15 to rotate via connecting gear Z3 16. Since clutch K2 14 is engaged, transmission gear Z6 17 is driven to rotate. Through engagement gear Z7 19, which meshes with transmission gear Z6 17, the power is transmitted to the main shaft 8. After passing through the main shaft 8, the power is transmitted to the first-stage sun gear 24 and second-stage sun gear 27 via transmission shaft L20. Second-stage sun gear 27 drives multiple second-stage planetary gears 28 to rotate. At the same time, since clutch K6 21 is engaged, transmission shaft L20 directly drives the first-stage planetary carrier 26 to rotate, thereby driving the second-stage ring gear 32 to rotate, further driving multiple second-stage planetary gears 28 to rotate. Thus, the power is transmitted to the output assembly 30 via the second-stage planetary carrier 29.

[0075] Preheating mode: K1 clutch 10, K6 clutch 21 and K5 clutch 22 are partially closed, and sliding friction generates heat, thereby preheating.

[0076] Brake mode: K6 clutch 21 and K5 clutch 22 are partially engaged, and sliding friction is used to gradually apply the brakes.

[0077] Table 1 Shift Logic

[0078]

[0079] By replacing the traditional dedicated brakes and preheaters with the aforementioned preheating and braking modes, the overall vehicle structure can be simplified, weight reduced, and space saved.

[0080] This invention addresses the pain points in current oil fracturing operations by improving the clutch filling and discharging structure by adding a quick-release valve. This increases the shifting response speed, reduces shifting time, shortens the friction plate slippage time, solves the problem of friction plate burnout, and improves product reliability.

[0081] The calibration-free technology enables one-button paralleling. The calibration-free technology adopts existing technology, referring to the "A Calibration-Free Motor Power Shift Gearbox" with publication number "CN 116877665 A".

[0082] The first gear ratio is high, reaching 4.835, which is higher than the 3.75 and 4.47 of its peers, making it easier to switch gears; at the same time, the switching flow is small, and the flow pulsation is small during switching, which improves the stability of the oil fracturing system.

[0083] By adjusting the speed ratio difference between each gear to within 1.25, the problem of not being able to engage gears was solved. At the same time, the uniform speed ratio difference between each gear results in less shift shock and improves product reliability.

[0084] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used to facilitate the description of this invention and to simplify the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0085] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0086] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention.

Claims

1. A high-power oil fracturing truck transmission system, characterized in that, It includes an integrated torque converter and gearbox, wherein the gearbox adopts a fixed-axis + planetary structure; The torque converter includes a housing a and a torque converter mechanism disposed within the housing a, the torque converter mechanism being connected to the input component; The gearbox includes a housing b, which is fixedly connected to housing a. The housing b contains a parallel shaft transmission system that is connected to the output end of the torque converter and a planetary gear transmission system that is connected to the output end of the parallel shaft transmission system. The output end of the planetary gear transmission system is connected to the output assembly. The parallel shaft transmission system has three gears via three clutches, and the planetary gear transmission system has three gears via three clutches. The three clutches of the parallel shaft transmission system and the three clutches of the planetary gear transmission system are cross-engaged to form nine gears, and the speed ratios are set to 4.835~4.154~3.571~2.603~2.237~1.923~1.354~1.163~1. The parallel shaft transmission system includes a main shaft, a side shaft m, and a side shaft n rotatably disposed within the housing b. The side shafts m and n are located on the side of the main shaft. The output end of the torque converter is provided with a Z1 transmission gear. The main shaft is connected to the Z1 transmission gear via a K1 clutch. A Z5 engagement gear and a Z7 engagement gear are fixedly disposed on the main shaft. The side shafts m and n are respectively connected to the Z1 transmission gear via fixed Z2 and Z3 engagement gears. A Z4 transmission gear and a Z6 transmission gear are also rotatably disposed on the side shafts m and n respectively. The side shaft m is connected to the Z4 transmission gear via a K2 clutch, and the side shaft n is connected to the Z6 transmission gear via a K3 clutch. The Z4 and Z6 transmission gears are respectively connected to the Z5 engagement gear and the Z7 engagement gear. The planetary gear transmission system is connected to the main shaft.

2. The high-power oil fracturing truck transmission system as described in claim 1, characterized in that, The planetary gear transmission system includes a transmission shaft L fixedly connected to the main shaft. A primary sun gear and a secondary sun gear are fixedly mounted on the transmission shaft L. A primary ring gear is connected to the periphery of the primary sun gear through several primary planet gears. The primary ring gear is connected to the housing b through a K5 clutch. A secondary ring gear is connected to the periphery of the secondary sun gear through several secondary planet gears. The secondary ring gear is connected to the housing b through a K4 clutch. A K6 clutch is also provided on the transmission shaft L. The K6 clutch is connected to several primary planet gears through a primary planet carrier. The primary planet carrier is connected to the secondary ring gear through a Z13 connecting gear. The several secondary planet gears are connected to the output component through the secondary planet carrier.

3. The high-power oil fracturing truck transmission system as described in claim 2, characterized in that, The K1, K2, K3, K6, K5, and K4 clutches operate on the same principle, including a fixed inner hub and piston seat. The inner hub and piston seat are spaced apart, and a movable piston is located between them. A movable outer hub is fitted around the outer side of the inner hub. The inner hub has several sliding friction plates, and the outer hub has several sliding steel plates. The friction plates and steel plates are arranged alternately. The piston seat has an oil cavity on the side facing the inner hub. A portion of the piston is embedded in the oil cavity and slidably sealed. The oil cavity is connected to a pressure oil passage, and the piston is connected to an elastic reset element.

4. The high-power oil fracturing truck transmission system as described in claim 3, characterized in that, The piston seat is equipped with a quick-release valve, and the piston seat has a connecting channel. The connecting channel has oil holes a, b, and c in sequence. Oil hole a connects to the housing body. The quick-release valve is located in the connecting channel. Oil holes b and c connect to the oil chamber. The connecting channel is connected to an oil inlet hole, which is located between oil holes a and b and is connected to a pressure oil passage. The quick-release valve includes a second spring and a valve core located in the connecting channel. The valve core is matched with the connecting channel and is pushed and slid by the second spring.

5. The high-power oil fracturing truck transmission system as described in claim 3, characterized in that, The elastic reset component includes a fixed spring plate located between the piston and the inner hub, and the spring plate is connected to the piston by a first spring.

6. The high-power oil fracturing truck transmission system as described in claim 1, characterized in that, The torque converter includes a drive shaft b, a cover wheel, a pump wheel, a turbine, and a guide wheel. The pump wheel is connected to the input component through the cover wheel. The pump wheel, turbine, and guide wheel are mounted on the drive shaft b. The drive shaft b is rotatably disposed within the housing a, and a parallel shaft transmission system is connected to the drive shaft b. The turbine is fixedly connected to the drive shaft b. The guide wheel is disposed between the pump wheel and the turbine, and a locking clutch is also provided between the pump wheel and the turbine.

7. The high-power oil fracturing truck transmission system as described in claim 6, characterized in that, The torque converter is connected to a power take-off mechanism, which includes a drive gear fixed on the pump wheel. The drive gear is connected to a pump gear via a power take-off gear located inside the housing a. The pump gear is connected to a return oil pump, which is located on the housing a.

8. The high-power oil fracturing truck transmission system as described in claim 1, characterized in that, It also includes a lubrication system, which includes a main oil valve and several secondary oil valves located on housing a and housing b. The main oil valve is connected to an oil supply pipe, and the main oil valve is connected to several secondary oil valves through several branch oil pipes. The several secondary oil valves are independently connected to various lubrication components through lubrication oil pipes, and the lubrication oil pipes are built into housing a and housing b.

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