Clutch of marine gearbox
By designing sinusoidal steel plates and high-pressure lubrication oil channels in marine gearbox clutches, the lubrication and cooling problems between friction plates and steel plates are solved, achieving the effects of reducing wear and increasing service life.
Patent Information
- Application Number
- CN202422806372.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-18
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2034-11-18
AI Technical Summary
Existing marine gearbox clutches have difficulty for oil to pass between the friction plates and steel plates during disengagement, resulting in increased oil temperature, accelerated wear, and unreliable return spring positioning, which affects the timeliness of disengagement.
The friction plates and steel plates are designed with a sinusoidal waveform along the circumference, combined with high-pressure oil passages and lubrication oil passages to form effective lubrication and rapid cooling, reduce torque, avoid dragging, and ensure reliable piston return through spring assembly.
It effectively reduces the torque between the friction plates and the steel plates, lowers the wear rate, and improves the service life and disengagement time of the clutch.
Smart Images
Figure CN223498487U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a clutch for a marine gearbox, belonging to the technical field of wet clutches. Background Technology
[0002] Small and medium-power marine diesel engines typically operate at high speeds but cannot reverse, thus requiring a marine gearbox to form a marine power unit. A marine gearbox is a transmission device with forward and reverse rotation, clutch, and deceleration functions, capable of withstanding propeller thrust. As a crucial component of the ship's main propulsion system, a marine gearbox generally consists of six main parts: input components, output components, oil pump drive unit, clutch, gearbox housing, and piping system. The clutch, a vital component of the marine gearbox, engages when the ship moves forward or backward, connecting the front main engine to the rear propeller shaft via the gearbox, enabling power and torque transmission. The main problems with existing marine gearbox clutches are:
[0003] 1. If the internal friction plates of the clutch in a marine gearbox are a combination of flat plates and friction plates, when the clutch disengages, the adhesion of the oil film between the friction plates and the steel plates inside the clutch makes it difficult for the oil to pass between the two plates. Instead, the oil can only pass through the oil grooves on the friction plates. The difficulty in throwing the oil out causes the local oil temperature to rise, accelerates wear, and also increases the torque between adjacent friction plates and steel plates, resulting in dragging during disengagement.
[0004] 2. If the internal friction plates of a marine gearbox clutch are a combination of disc-shaped plates and friction plates, when the clutch disengages, the disc-shaped plates recover their elasticity and instantly separate the friction plates, which increases the gap between the plates and reduces the force generated by the oil film adhesion, thus reducing the torque. However, since the disc-shaped plates are like bowls, the gap between the outermost ring and the friction plates is very small, which increases the difficulty of oil ejection and makes the local oil temperature rise more easily due to poor oil discharge.
[0005] 3. A return spring with a large force is used to push the piston back, but the positioning reliability of the return spring is not high, resulting in a reduction in the rebound force and affecting the timeliness of clutch disengagement. Utility Model Content
[0006] The clutch for marine gearboxes provided by this utility model reduces the torque between the friction plates and steel plates, avoids dragging, effectively lubricates the friction plates and steel plates, and quickly removes the heat between them, thus rapidly cooling the friction plate assembly, preventing localized overheating of the oil, reducing the wear rate of the steel plates and friction plates, and improving the service life of the clutch.
[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0008] A clutch for a marine gearbox includes an input shaft, a transmission gear press-fitted onto the input shaft, and a rotatable drive gear mounted on the input shaft. A piston is installed between the input shaft and the transmission gear. A friction plate assembly corresponding to the piston is installed between the transmission gear and the drive gear. The piston is sealed to the input shaft and the transmission gear respectively. A spring assembly is installed on the input shaft to press the piston against the transmission gear. A high-pressure oil passage is opened on the input shaft to introduce high-pressure oil and drive the piston. The piston moves with the entry of high-pressure oil, pressing the friction plate assembly and compressing the spring assembly. The friction plate assembly includes friction plates splined to the transmission gear and steel plates splined to the drive gear. The friction plates and steel plates are alternately arranged axially. The steel plates have a sinusoidal waveform along the circumference. A lubricating oil passage is opened on the input shaft. An oil inlet is opened on the drive gear, which communicates with the lubricating oil passage to introduce lubricating oil into the friction plate assembly. An oil outlet is opened on the transmission gear for the lubricating oil to be thrown out.
[0009] Preferably, the transmission gear consists of an interference section that is interference-fitted with the input shaft and a mating section that is mated with the friction plate assembly. The inner diameter of the mating section is larger than the outer diameter of the input shaft. The driving gear extends into the mating section and the input shaft, forming an axial gap between the driving gear and the input shaft. The spring assembly is installed in the axial gap.
[0010] Preferably, the spring assembly includes a spring seat sleeved on the input shaft and abutting against the piston, a spring retaining ring positioned on the input shaft, and a spring sandwiched between the spring seat and the spring retaining ring. The spring retaining ring is pressed against a support bearing on the input shaft by a washer, and an axial wire retaining ring for axial positioning of the spring retaining ring is assembled on the input shaft. The spring pushes the piston to press against the transmission gear.
[0011] Preferably, the lubricating oil passage is connected to the oil inlet hole through an axial gap, the oil inlet hole is evenly distributed along the axial direction on the drive gear, and the oil outlet hole is evenly distributed along the axial direction on the mating section.
[0012] Preferably, a pressure plate is positioned on the mating section between the mating section and the drive gear. The pressure plate is located on the outside of the piston. The friction plate assembly is axially mounted between the pressure plate and the piston. The innermost friction plate contacts the piston end face, and the outermost friction plate contacts the pressure plate.
[0013] The beneficial effects of this utility model are:
[0014] This invention relates to a marine gearbox clutch where the steel plates are designed with a sinusoidal waveform along the circumference. When the piston is not pressing against the friction plate assembly, the steel plates are in line contact with the friction plates. When the piston presses against the friction plate assembly, the steel plates deform, increasing the contact area between them and the friction plates. This connects the transmission gear and the drive gear into a single unit, forming the clutch engagement plate. When the piston is pushed back by the spring assembly, disengaging the clutch, the rebound force of the steel plates quickly springs the friction plates away, restoring them to line contact. This effectively reduces the viscous force of the oil, decreases the torque between the friction plates and the steel plates, and prevents dragging of the clutch. After disengagement, an oil-throwing channel is formed between the corrugated steel sheet and the friction plate. An oil inlet is opened on the drive gear, an oil outlet is opened on the transmission gear, and a lubricating oil passage is opened on the input shaft. The lubricating oil is introduced from the lubricating oil passage, enters through the oil inlet, and quickly passes through the oil-throwing channel between the steel sheet and the friction plate. It is thrown out from the oil outlet, which not only forms effective lubrication between the friction plate and the steel sheet, but also quickly removes the heat between the friction plate and the steel sheet, forming rapid cooling of the friction plate assembly. This avoids excessively high local oil temperature, reduces the wear rate of the steel sheet and the friction plate, and improves the service life of the clutch. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the clutch of a marine gearbox in a specific embodiment.
[0016] Figure 2 for Figure 1 A magnified view of a portion of the image.
[0017] Figure 3 This is a partial schematic diagram showing a steel sheet exhibiting a sinusoidal waveform along its circumference. Detailed Implementation
[0018] The following is combined with Figures 1-3 The embodiments of this utility model will be described in detail below.
[0019] The clutch of a marine gearbox includes an input shaft 1, a transmission gear 2 interference-fitted onto the input shaft 1, and a drive gear 3 rotatably mounted on the input shaft 1. A piston 4 is installed between the input shaft 1 and the transmission gear 2. A friction plate assembly 5 corresponding to the piston 4 is installed between the transmission gear 2 and the drive gear 3. The piston 4 is sealed to both the input shaft 1 and the transmission gear 2. A spring assembly 6 is mounted on the input shaft 1 to press the piston 4 against the transmission gear 2. A high-pressure oil passage 7 is provided on the input shaft 1 to introduce high-pressure oil to drive the piston 4. 4. The friction plate assembly 5 is pressed and compressed by the entry of high-pressure oil, and the spring assembly 6 is compressed. The friction plate assembly 5 includes a friction plate 51 splined to the transmission gear 2 and a steel plate 52 splined to the drive gear 3. The friction plate 51 and the steel plate 52 are alternately arranged along the axial direction. The steel plate 62 is sinusoidal in the circumferential direction. A lubricating oil passage 8 is opened on the input shaft 1. An oil inlet hole 31 connected to the lubricating oil passage 8 is opened on the drive gear 3 to guide the lubricating oil into the friction plate assembly. An oil outlet hole 21 is opened on the transmission gear 2 to allow the lubricating oil to be thrown out.
[0020] The clutch in the marine gearbox described above features a steel plate 52 with a sinusoidal waveform along its circumference. When the piston 4 is not pressing against the friction plate assembly 5, the steel plate 52 and the friction plate 51 are in line contact. When the piston 4 presses against the friction plate assembly 5, the steel plate 52 deforms, increasing the contact area between it and the friction plate 51. This connects the transmission gear 2 and the drive gear 3 into a single unit, forming the clutch engagement. When the piston 4 is pushed back by the spring assembly 6, disengaging the clutch, the rebound force of the steel plate 52 quickly springs the friction plate 51 away, restoring it to line contact. This effectively reduces oil viscosity, decreases the torque between the friction plate 51 and the steel plate 52, and avoids dragging. The waveform after clutch disengagement... An oil-throwing channel is formed between the steel plate 52 and the friction plate 51. An oil inlet hole 31 is opened on the drive gear 3, an oil outlet hole 21 is opened on the transmission gear 2, and a lubricating oil passage 8 is opened on the input shaft 1. The lubricating oil is introduced from the lubricating oil passage 8, enters through the oil inlet hole 31, and quickly passes through the oil-throwing channel between the steel plate 52 and the friction plate 51. It is thrown out from the oil outlet hole 21, which not only forms effective lubrication between the friction plate 51 and the steel plate 52, but also quickly removes the heat between the friction plate 51 and the steel plate 52, forming rapid cooling of the friction plate assembly 5, avoiding excessively high local oil temperature, reducing the wear rate of the steel plate 52 and the friction plate 51, and improving the service life of the clutch.
[0021] The transmission gear 2 consists of an interference section 22 that interferes with the input shaft 1 and a mating section 23 that mates with the friction plate assembly 5. The inner diameter of the mating section 23 is larger than the outer diameter of the input shaft 1. The driving gear 3 extends between the mating section 23 and the input shaft 1, forming an axial clearance A between the driving gear 3 and the input shaft 1. The spring assembly 5 is installed in the axial clearance. The friction plate assembly 5 is installed between the mating section 23 and the driving gear 3. The axial clearance A between the driving gear 3 and the input shaft 1 is used to install the spring assembly 6. This fully utilizes the space between the transmission gear, the input shaft, and the driving gear, improving the structural compactness of the clutch. It also facilitates the mating of the spring assembly 6 with the piston 4 and the mating of the friction plate assembly 5 with the transmission gear 2 and the driving gear 3.
[0022] The spring assembly 6 includes a spring seat 61 fitted onto the input shaft 2 and abutting against the piston 4, a spring retainer ring 62 positioned on the input shaft 1, and a spring 63 sandwiched between the spring seat 61 and the spring retainer ring 62. The spring retainer ring 62 is pressed against the support bearing 9 on the input shaft 1 by a washer, and an axial wire retainer ring 10 is mounted on the input shaft 1 to axially position the spring retainer ring 62. The spring 63 pushes the piston 4 to press against the transmission gear 2. In the clutch disengaged state, the spring 63 presses the piston 4 against the transmission gear 2 through the spring seat 61. High-pressure oil pressure enters from the high-pressure oil passage 7 into the sealed chamber formed by the piston 4, the transmission gear 2, and the input shaft 1, causing the piston 4 to overcome the pressure of the spring 63 and move towards the friction plate assembly 5, pressing it down. The spring 63 is compressed. When the high-pressure oil passage 7 no longer receives high-pressure oil, the elastic force of the spring 63 pushes the piston 4 back, resulting in clutch disengagement. The spring retainer ring 62 is pressed against the support bearing 9 of the input shaft 1 by a washer, and is axially positioned by the axial wire retainer ring 10 on the input shaft 1. This effectively improves the axial load-bearing capacity of the spring retainer ring 62, ensures that the spring retainer ring 62 will not deform or tilt when the piston 4 presses against the friction plate group 5 so that the spring 63 is compressed, and ensures the rebound force of the spring 63, thereby ensuring the timely disengagement of the clutch.
[0023] The lubricating oil passage 8 is connected to the oil inlet 31 through the axial clearance A. The oil inlet 31 is evenly spaced along the axial direction on the drive gear 3, and the oil outlet 21 is evenly spaced along the axial direction on the mating section 23. Lubricating oil enters the axial clearance A through the lubricating oil passage 8. The high-speed rotation of the input shaft 1 sends the oil in the axial clearance A to the oil inlet 31, which enters between the steel plate 52 and the friction plate 51. The steel plate 52 is wavy, forming an oil passage between it and the friction plate 51. The oil is thrown out from the oil outlet 21 through the oil passage, forming lubrication and rapid cooling of the friction plate assembly 5, avoiding excessively high local oil temperature, reducing the wear rate of the steel plate 52 and the friction plate 51, and improving the service life of the clutch.
[0024] The mating section 23 is equipped with a pressure plate 24 positioned between the mating section 23 and the drive gear 3. The pressure plate 24 is located outside the piston 4. The friction plate assembly 5 is axially mounted between the pressure plate 24 and the piston 4. The innermost friction plate 51 contacts the end face of the piston 4, and the outermost friction plate 51 contacts the pressure plate 24. The pressure plate 24 is positioned on the mating section 23. The outermost and innermost parts of the friction plate assembly 5 are both friction plates 51. The innermost friction plate 51 contacts the piston 4, and the outermost friction plate 51 contacts the pressure plate 24. The friction plates 51, piston 4, and pressure plate 24 all rotate synchronously with the input shaft 1, which can prevent excessive wear of the outermost friction plate 51 and ensure that the friction plate assembly 5 can only move axially between the pressure plate 24 and the piston 4, resulting in high structural reliability.
[0025] The technical solutions of the embodiments of this utility model have been fully described above with reference to the accompanying drawings. It should be noted that the described embodiments are only a part of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
Claims
1. A clutch for a marine gearbox, comprising an input shaft, a transmission gear interference-fitted on the input shaft, and a drive gear rotatably mounted on the input shaft, wherein a piston is installed between the input shaft and the transmission gear, and a friction plate assembly corresponding to the piston is installed between the transmission gear and the drive gear, the piston is sealed to the input shaft and the transmission gear respectively, a spring assembly is installed on the input shaft to press the piston against the transmission gear, and a high-pressure oil passage is provided on the input shaft to introduce high-pressure oil to drive the piston, the piston moves with the entry of high-pressure oil to press the friction plate assembly and compress the spring assembly, characterized in that: The friction plate assembly includes a friction plate connected to the transmission gear spline and a steel plate connected to the drive gear spline. The friction plate and the steel plate are alternately arranged along the axial direction. The steel plate has a sinusoidal waveform along the circumference. A lubricating oil passage is opened on the input shaft. An oil inlet hole connected to the lubricating oil passage is opened on the drive gear to guide the lubricating oil into the friction plate assembly. An oil outlet hole is opened on the transmission gear for the lubricating oil to be thrown out.
2. The clutch of the marine gearbox according to claim 1, characterized in that: The transmission gear consists of an interference section that is interference-fitted with the input shaft and a mating section that is mated with the friction plate assembly. The inner diameter of the mating section is larger than the outer diameter of the input shaft. The driving gear extends into the mating section and the input shaft, forming an axial gap between the driving gear and the input shaft. The spring assembly is installed in the axial gap.
3. The clutch for a marine gearbox according to claim 1, characterized in that: The spring assembly includes a spring seat fitted on the input shaft and abutting against the piston, a spring retaining ring positioned on the input shaft, and a spring sandwiched between the spring seat and the spring retaining ring. The spring retaining ring is pressed against a support bearing on the input shaft by a washer, and an axial wire retaining ring is mounted on the input shaft to axially position the spring retaining ring. The spring pushes the piston to press against the transmission gear.
4. The clutch for a marine gearbox according to claim 3, characterized in that: The lubricating oil passage is connected to the oil inlet hole through an axial gap. The oil inlet hole is evenly distributed along the axial direction on the drive gear, and the oil outlet hole is evenly distributed along the axial direction on the mating section.
5. The clutch for a marine gearbox according to claim 4, characterized in that: The mating section is positioned with a pressure plate located between the mating section and the drive gear. The pressure plate is located on the outside of the piston. The friction plate assembly is installed axially between the pressure plate and the piston. The innermost friction plate is in contact with the piston end face, and the outermost friction plate is in contact with the pressure plate.