A v-gearbox

Abstract

The application discloses a V-shaped gear box and relates to the technical field of ship power transmission, which comprises a box component, an input shaft component, a transmission shaft component and an output shaft component. The input shaft of the input shaft component and the output shaft of the output shaft component are arranged on the same side to form a V-shaped structure. The output shaft and the input shaft have an inclination angle for matching the fluid dynamics demand when the ship sails. The application effectively solves the problems of simple structure, small volume and light weight of the gear box. The power from the flywheel of the diesel engine is directly introduced into the forward transmission gear through the end face spline tooth engagement of the input coupling. The clutch in the forward transmission gear is designed to compress the inner and outer friction plates to drive the forward driving gear, which is output through the output gear and the fixed output shaft. The transmission route is short, and the transmitted torque is large. The reverse rotation is output through the forward transmission gear, the reverse transmission gear, the reverse driving gear, the output gear and the output shaft.

Description

Technical Field

[0001] This invention relates to the field of marine power transmission technology, specifically a V-type gearbox. Background Technology

[0002] Existing marine gearboxes typically employ a parallel arrangement of the input and output shafts or a small tilt angle design (e.g., 5-10 degrees) on opposite sides. This design approach has several drawbacks:

[0003] Large space occupation: The input and output shafts of traditional gearboxes are arranged in parallel, resulting in a long unit length and occupying a lot of space on the ship, which is especially difficult to adapt to small vessels such as yachts and high-speed boats.

[0004] Complex and bulky structure: Traditional designs require multi-stage gear transmission, resulting in large size and weight.

[0005] Low efficiency: Traditional gearboxes with parallel shaft drives or small tilt angles on opposite sides are not suitable for the water flow angle during high-speed ship navigation. Summary of the Invention

[0006] The purpose of this invention is to provide a compact and lightweight V-type gearbox. By arranging the input and output shafts on the same side to form a V-shape and optimizing the tilt angle, the power transmission path is shortened. The gearbox consists of a housing component, an input shaft component, a drive shaft component, an output shaft component, and an electronically controlled valve assembly. Reversing / forward operation is achieved through a hydraulically controlled friction plate clutch.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a V-type gearbox, comprising a housing component, an input shaft component, a transmission shaft component, and an output shaft component, wherein the input shaft of the input shaft component and the output shaft of the output shaft component are arranged on the same side to form a V-shaped structure, and the output shaft and the input shaft have an inclination angle θ to match the hydrodynamic requirements of ship navigation.

[0008] Preferably, the housing component includes a lower housing, a front housing, and a rear housing. The lower housing is connected to the front housing and the rear housing through a mating surface, and axial reinforcing ribs are arranged at the mating surface to withstand gear rotation and propeller thrust.

[0009] Preferably, the input shaft component includes an input shaft, an input coupling, an input transmission gear, a traveling piston, a first inner friction plate, and a first outer friction plate. The input coupling directly meshes with the input transmission gear via a spline, and the traveling piston hydraulically pushes the first inner friction plate and the first outer friction plate together to achieve power transmission.

[0010] Preferably, the input shaft component further includes a working oil passage and a first return spring, the working oil passage being used to guide hydraulic oil to push the traveling piston, and the first return spring being used to reset the piston when the hydraulic pressure is released.

[0011] Preferably, the drive shaft component includes a drive shaft, a reversing drive gear, a reversing piston, a second inner friction plate, and a second outer friction plate. The reversing drive gear meshes with the input drive gear, and the reversing piston hydraulically pushes the second inner friction plate and the second outer friction plate to engage, thereby realizing the transmission of reversing power.

[0012] Preferably, the drive shaft component further includes a reversing working oil passage and a second return spring, wherein the reversing working oil passage is interlocked with the working oil passage to ensure that the forward and reverse clutches do not engage simultaneously.

[0013] Preferably, the output shaft component includes an output shaft, an output gear, a bearing E, and a bearing F. The output gear is fixedly mounted on the output shaft, and the bearing F is used to withstand the axial thrust of the propeller.

[0014] Preferably, it also includes an electronically controlled valve assembly, which includes a forward / reverse control valve and a valve seat, for controlling the forward and reverse pistons via hydraulic signals to achieve switching between forward, reverse, and stop operating conditions.

[0015] Preferably, the electronically controlled valve assembly is a manually or electrically controlled hydraulic valve, and is equipped with an interlocking mechanism to prevent the forward and reverse clutches from engaging simultaneously.

[0016] Preferably, the tilt angle θ is determined by the following method:

[0017] Step 1: Determine the design speed range V_min-V_max and the main ship parameters, including length L, beam B and displacement D, based on the type of the target ship;

[0018] Step 2: Obtain the pitch angle distribution of the ship at characteristic speeds through CFD simulation, including the minimum speed pitch angle α_min, the cruising speed pitch angle α_cruise, and the maximum speed pitch angle α_max;

[0019] Step 3: Calculate the ship type coefficient: λ=(L / B)×(V_cruise / )×(D / L³);

[0020] Where V_cruise is the cruising speed;

[0021] Step 4: Based on the formula:

[0022] The optimal tilt angle is calculated as θ = λ × (0.3α_min + 0.5α_cruise + 0.2α_max) × k + Δθ.

[0023] Where k is the installation constraint coefficient, with a value ranging from 0.85 to 0.95;

[0024] Δθ is the thrust line compensation angle, with a value range of ±1.5°;

[0025] The design range of θ is 5°-28° to accommodate the dynamic requirements of different ship types and optimize propulsion efficiency.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] This invention effectively solves the problems of a simple gearbox structure, small size, and light weight. Power from the diesel engine flywheel is directly fed into the forward drive gear via the input coupling 21 through end-face spline gear engagement. A clutch designed within the forward drive gear presses against the inner and outer friction plates, driving the forward drive gear, which then outputs power via the output gear and a fixed output shaft. The transmission route is short, and the transmitted torque is large. Reversing is achieved through the forward drive gear, reverse drive gear, reverse drive gear, output gear, and output shaft. The input and output ends of the gearbox are arranged on the same side, forming a V-shaped transmission, shortening the axial length of conventional unit layouts. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of a V-type gearbox according to the present invention;

[0029] Figure 2 This is a schematic diagram of the gearbox assembly in a V-type gearbox according to the present invention;

[0030] Figure 3 This is a schematic diagram of the housing component in a V-type gearbox according to the present invention;

[0031] Figure 4 This is a schematic diagram of the structure of the input shaft component in a V-type gearbox according to the present invention;

[0032] Figure 5 This is a schematic diagram of the structure of a transmission shaft component in a V-type gearbox according to the present invention;

[0033] Figure 6 This is a schematic diagram of the output shaft component in a V-type gearbox according to the present invention;

[0034] Figure 7 This is a schematic diagram of the structure of an electrically controlled valve assembly in a V-type gearbox according to the present invention;

[0035] Figure 8 for Figure 2 Schematic diagram of the cross-sectional structure of the AA surface in the middle;

[0036] Figure 9 for Figure 2 A schematic diagram of the cross-sectional structure of the BB plane.

[0037] In the picture:

[0038] 1. Housing components: 12. Lower housing, 13. Output shaft front cover, 14. Input shaft front cover, 15. Front housing, 16. PTO housing cover, 17. Rear housing, 18. Input shaft rear cover, 19. Input shaft end cover, 20. Output shaft end cover;

[0039] 11. Driveshaft Components: 40. Driveshaft Front Cover, 41. Oil Pump Coupling, 42. Oil Pump Coupling Ring, 43. Bearing C, 44. Reverse Drive Gear, 45. Reverse Piston, 46. Second Inner Friction Plate, 47. Second Outer Friction Plate, 48. Reverse Clutch Pressure Plate, 49. Positioning Plate, 50. Reverse Drive Gear, 51. Bearing D, 52. Driveshaft, 53. Reverse Working Oil Passage, 54. Reverse Lubricating Oil Passage, 55. Bearing Housing, 56. Wear Plate, 57. Second Shaft Retaining Ring, 58. Second Spring Retaining Plate, 59. Second Return Spring;

[0040] 2. Output shaft components: 60 Output shaft, 61 Output shaft spacer, 62 Bearing E, 63 Bearing F, 64 Bearing baffle, 65 Bearing spacer, 66 Locking nut assembly, 67 Output gear, 68 Bearing G, 69 Small spacer, 70 Shaft retaining ring;

[0041] 3. Input shaft components: 21 Input coupling, 22 Coupling pressure plate, 23 Input transmission gear, 24 Bearing A, 25 Carrying piston, 26 First return spring, 27 First inner friction plate, 28 First outer friction plate, 29 Pressure plate, 30 Friction plate baffle, 31 Drive gear, 32 Bearing B, 33 Bearing seat, 34 Input shaft, 35 Working oil passage, 36 Lubricating oil passage, 37 Wear plate, 38 First shaft retaining ring, 39 First spring baffle;

[0042] 4. External oil supply pump; 5. PTO auxiliary oil pump components; 6. Pore cap;

[0043] 7. Electronic valve assembly 7: 71 Reversing control valve, 72 Valve seat;

[0044] 8. Filter assembly, 9. Oil pump, 10. Cooler. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] This invention relates to a V-type gearbox. The core innovation of this gearbox lies in its unique V-shaped structural arrangement, which places the input and output shafts on the same side, forming a compact, foldable power unit. This significantly shortens the power transmission path, achieving a small size and light weight. The gearbox mainly consists of a housing component 1, an input shaft component 3, a transmission shaft component 11, an output shaft component 2, an electronically controlled valve assembly 7, and a filter assembly 8. These components work collaboratively through precise connections and are hydraulically controlled by the electronically controlled valve assembly 7 to perform reversing, forward, and parking functions.

[0047] Structural composition and connection method:

[0048] Reference Figure 1 , Figure 2 and Figure 3 As shown, housing component 1, serving as the supporting foundation, consists of a lower housing 12, an output shaft front cover 13, an input shaft front cover 14, a front housing 15, a PTO housing cover 16, a rear housing 17, an input shaft rear cover 18, an input shaft end cover 19, and an output shaft end cover 20. The housing adopts a split design, with axial reinforcing ribs arranged at the mating surfaces to withstand the gear rotation force and propeller thrust, ensuring overall rigidity. This design is necessary due to the complex operating conditions of ships, requiring stress dispersion and preventing deformation.

[0049] Reference Figure 4 As shown, input shaft component 3 is connected to the diesel engine flywheel via input coupling 21. The rear end of input coupling 21 directly meshes with input transmission gear 23 using a spline configuration, enhancing transmission capacity. Components include a traveling piston 25, a first return spring 26, a first inner friction plate 27, and a first outer friction plate 28, etc., supported on the housing by bearings A24 and B32. The spline meshing design shortens the path and reduces energy loss because traditional key connections are prone to loosening, while splines can provide higher torque.

[0050] Reference Figure 5 As shown, the drive shaft assembly 11 is used for the reversing function and includes a reversing drive gear 44, a reversing piston 45, a second inner friction plate 46, and a second outer friction plate 47, etc., supported by bearings C43 and D51. It meshes with the gear of the input shaft assembly 3 to achieve power reversal. The design reason is to meet the requirements of ship reversing and avoid additional complex mechanisms.

[0051] Reference Figure 6 As shown, output shaft component 2: Output gear 67 is fixedly mounted on output shaft 60 and supported by bearings E62 and G68. Bearing E63 is specifically designed to withstand propeller thrust. Output shaft 60 is inclined at a V-shape with input shaft 34 to match the fluid lift angle during high-speed ship navigation, thereby reducing resistance and improving efficiency.

[0052] Reference Figure 7As shown, the electronically controlled valve assembly 7 consists of a reversing control valve 71 and a valve seat 72. It controls the clutch action through hydraulic signals and is designed with an interlock mechanism to prevent misoperation and ensure reliability.

[0053] This invention employs a V-shaped arrangement instead of the traditional parallel shaft, optimizing the unit length and achieving the requirements of light weight, small size, and compact space. Input and output are on the same side, shortening the path and combining this with direct spline engagement improves torque transmission efficiency. The tilt design is based on ship dynamics, adapting the structure to actual navigation conditions, forming a systematic solution that ultimately achieves lightweighting and miniaturization. This is of great significance for gearboxes used in our next generation of yachts, high-speed boats, law enforcement vessels, fishing boats, and workboats.

[0054] Based on the above structure, the present invention controls the hydraulic circuit through the electronically controlled valve assembly 7 to realize three working conditions: forward movement, reverse movement, and parking.

[0055] Ride-sharing conditions:

[0056] When the vessel needs to move forward, the electronically controlled valve assembly 7 receives a command, and the forward control valve 71 actuates. Hydraulic oil flows through the working oil passage 35 to push the forward piston 25 in the input shaft assembly 34. The piston compresses the first return spring 26, pressing the first inner friction plate 27 and the outer friction plate 28 together, causing the friction plates to engage. At this time, the diesel engine power is transmitted to the input drive gear 23 via the spline of the input coupling 21, and then drives the drive gear 31 through the engaged friction plates. The drive gear 31 meshes with the output gear 67 on the output shaft 60, driving the output shaft 60 to rotate, and finally driving the propeller to rotate forward via the tail shaft, propelling the vessel forward. The entire process has a short path and high efficiency because the friction plates engage quickly, and the spline engagement reduces sliding losses.

[0057] Reversing operation:

[0058] When reversing is required, the electronic control valve assembly 7 switches, and the forward / reverse control valve 71 allows hydraulic oil to flow through the reverse working oil passage 53 to push the reverse piston 45 in the drive shaft assembly 11. The piston presses against the second inner friction plate 46 and the second outer friction plate 47, engaging the reverse transmission gear 44 and the reverse drive gear 50. Power is transmitted from the input transmission gear 23 through the reverse transmission gear 44. Due to the change in gear meshing direction, the reverse drive gear 50 drives the output gear 67 to reverse, causing the output shaft 60 to rotate in the opposite direction, the propeller to reverse, and the ship to move backward. At this time, the forward / reverse clutch automatically disengages, and the interlocking mechanism prevents power conflict.

[0059] Parking conditions:

[0060] When the control valve is in the stop position, neither the forward piston 25 nor the reverse piston 45 is hydraulically actuated. The second return spring 26 and the second return spring 59 reset the pistons, and the friction plates separate. The power to the input shaft 34 is cut off, the output shaft 60 stops rotating, and the gearbox is in neutral, ensuring the safe berthing of the vessel.

[0061] Throughout the entire operation, the housing component 1 distributes the load through reinforcing ribs, while the bearing E63 of the output shaft component 2 is specifically designed to absorb propeller thrust, thus preventing structural damage.

[0062] The electronically controlled valve assembly 7 can be designed for manual or electric control to adapt to different vessel requirements. The embodiments show that this design, verified by prototypes, is suitable for yachts, high-speed boats, etc., achieving a reduction in size. This working process, based on the precise fit of components, ensures the reliability and efficiency of the forward and reverse stopping functions.

[0063] Based on systematic optimization of ship dynamics, the tilt angle θ between the output and input shafts in this invention is not a simple geometric adjustment. Traditional gearboxes use a fixed small tilt angle (5-10°), which cannot match the hull heel angle generated during high-speed ship navigation, leading to interference between the power transmission path and the hull motion, increasing drag. This invention integrates ship type, speed range, and hydrodynamic parameters to dynamically adapt the tilt angle θ to the hull heel angle. The specific design is as follows:

[0064] First, the ship's type (e.g., high-speed boat, workboat) and speed range are determined during the design phase. These parameters determine the variation of the hull's heel angle. As the core of the transmission system, the gearbox's heel angle is pre-calculated based on these parameters in the early design phase to ensure overall efficiency after installation. The calculation of the heel angle θ depends on the target ship's length L, beam B, displacement D, and speed range (V_min, V_max). The ship type coefficient λ comprehensively reflects the hull characteristics, and combined with the heel angle distribution obtained from CFD simulation, the optimal heel angle is calculated.

[0065] The determination of the tilt angle θ in this invention includes the following steps, which are carried out simultaneously with the ship design during the gearbox design phase to ensure system compatibility:

[0066] Step 1: Parameter Acquisition Phase

[0067] Obtain the basic parameters of the target vessel, including vessel type (such as law enforcement vessel), length L, beam B, displacement D, and design speed range (V_min, V_max) (e.g., V_min=20 knots, V_max=40 knots for high-speed vessels). These parameters are clearly defined in the vessel design specifications.

[0068] Step 2: Pitch Angle Calculation Stage

[0069] Using CFD simulation software, such as STAR-CCM+, the hydrodynamics of the ship are simulated, and the pitch angles at characteristic speeds are extracted: minimum speed pitch angle α_min, cruising speed pitch angle α_cruise, and maximum speed pitch angle α_max. The simulation is based on hull line data to ensure the reliability of the results.

[0070] Step 3: Tilt Angle Optimization Calculation Stage:

[0071] Calculate the ship type coefficient λ = (L / B) × (V_cruise / )×(D / L³), this coefficient is dimensionless and reflects the hull's slenderness ratio, speed-to-length ratio and load characteristics.

[0072] Substitute into the formula:

[0073] θ=λ×(0.3α_min+0.5α_cruise+0.2α_max)×k+Δθ;

[0074] Where k is the installation constraint coefficient, which is determined by the space between the gearbox and the stern, and is taken as 0.85-0.95;

[0075] Δθ is the thrust line compensation angle, which is taken as ±1.5° through propeller wake field optimization;

[0076] The formula weights (0.3, 0.5, 0.2) emphasize the cruise condition while taking into account the entire speed range.

[0077] The final θ range is limited to 5°-28°, covering the needs of everything from high-speed boats to workboats, avoiding the shortcomings of traditional small tilt angles.

[0078] Step 4: Verification and Adjustment Phase

[0079] A prototype was built for real-ship testing to measure propulsion efficiency at different speeds. If the efficiency did not meet expectations, k or Δθ was fine-tuned for iterative optimization.

[0080] The dynamic matching of the tilt angle design can be demonstrated in the working process of the gearbox described above, for example:

[0081] like Figure 4 As shown, in the along-car operation, the electronically controlled valve assembly 7 actuates, and hydraulic oil pushes the along-car piston 25 through the working oil passage 35, pressing the first inner friction plate 27 and the first outer friction plate 28. Power is transmitted through the input shaft assembly 3. The output shaft 60 rotates at an inclination angle θ, which matches the hull's pitch angle, reducing water flow interference and minimizing propeller thrust loss.

[0082] like Figure 5 As shown, in the reversing mode, the reversing piston 45 actuates through the reversing working oil passage 53, and the power is reversed via the drive shaft component 11. The inclination angle θ is also pre-calculated based on the speed range to ensure the stability of the hull during reversing.

[0083] Overall, the housing component 1 distributes the load through reinforcing ribs, while the bearing F63 of the output shaft component 2 bears the thrust. The tilt angle θ makes the thrust direction consistent with the hull movement, thus improving overall efficiency.

[0084] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A V-type gearbox, characterized in that, It includes a housing component (1), an input shaft component (3), a transmission shaft component (11), and an output shaft component (2). The input shaft (34) of the input shaft component (3) and the output shaft (60) of the output shaft component (2) are arranged on the same side to form a V-shaped structure. The output shaft (60) and the input shaft (34) have an angle θ to match the hydrodynamic requirements of the ship during navigation. The input shaft component (3) includes an input shaft (34), an input coupling (21), an input transmission gear (23), a traveling piston (25), a first inner friction plate (27), and a first outer friction plate (28). The input coupling (21) directly meshes with the input transmission gear (23) via a spline. The traveling piston (25) hydraulically pushes the first inner friction plate (27) and the first outer friction plate (28) together to achieve power transmission. The drive shaft component (11) includes a drive shaft (52), a reversing drive gear (44), a reversing piston (45), a second inner friction plate (46), and a second outer friction plate (47). The reversing drive gear (44) meshes with the input drive gear (23). The reversing piston (45) hydraulically pushes the second inner friction plate (46) and the second outer friction plate (47) to engage, thereby realizing the reversing power transmission. The tilt angle θ is determined by the following method: Step 1: Determine the design speed range V_min-V_max and the main ship parameters, including length L, beam B and displacement D, based on the type of the target ship; Step 2: Obtain the pitch angle distribution of the ship at characteristic speeds through CFD simulation, including the minimum speed pitch angle α_min, the cruising speed pitch angle α_cruise, and the maximum speed pitch angle α_max; Step 3: Calculate the ship type coefficient: λ=(L / B)×(V_cruise / )×(D / L³); Where V_cruise is the cruising speed; Step 4: Based on the formula: The optimal tilt angle is calculated as θ = λ × (0.3α_min + 0.5α_cruise + 0.2α_max) × k + Δθ. Where k is the installation constraint coefficient, with a value ranging from 0.85 to 0.95; Δθ is the thrust line compensation angle, with a value range of ±1.5°; The design range of θ is 5°-28° to accommodate the dynamic requirements of different ship types and optimize propulsion efficiency.

2. A V-type gearbox according to claim 1, characterized in that: The housing component (1) includes a lower housing (12), a front housing (15) and a rear housing (17). The lower housing (12) is connected to the front housing (15) and the rear housing (17) through a mating surface, and axial reinforcing ribs are arranged at the mating surface to withstand gear rotation and propeller thrust.

3. A V-type gearbox according to claim 1, characterized in that: The input shaft component (3) also includes a working oil passage (35) and a first return spring (26), the working oil passage (35) being used to guide hydraulic oil to push the traveling piston (25), and the first return spring (26) being used to reset the piston when the hydraulic pressure is released.

4. A V-type gearbox according to claim 3, characterized in that: The drive shaft component (11) also includes a reversing working oil passage (53) and a second return spring (59), wherein the reversing working oil passage (53) is interlocked with the working oil passage (35) to ensure that the forward and reverse clutches do not engage simultaneously.

5. A V-type gearbox according to claim 1, characterized in that: The output shaft component (2) includes an output shaft (60), an output gear (67), a bearing E (62) and a bearing F (63). The output gear (67) is fixed on the output shaft, and the bearing F (63) is used to bear the axial thrust of the propeller.

6. A V-type gearbox according to claim 1, characterized in that: It also includes an electronically controlled valve assembly (7), which includes a forward and reverse control valve (71) and a valve seat (72) for controlling the forward piston (25) and the reverse piston (45) by means of a hydraulic signal to achieve switching between forward, reverse and stop working conditions.

7. A V-type gearbox according to claim 6, characterized in that: The electronically controlled valve assembly (7) is a hydraulic valve that is manually or electrically controlled, and is equipped with an interlocking mechanism to prevent the forward and reverse clutches from engaging simultaneously.

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