A thrust bearing vibration isolation structure

Abstract

The present invention discloses a thrust bearing vibration isolation structure, including a thrust shaft, a housing, a thrust block, a support bearing and a collar; the housing is sleeved on the thrust shaft, and a head is provided at the end of the housing; the collar is installed inside the housing, and the two are arranged on the thrust shaft from the inside to the outside; a vibration isolation assembly is provided inside the collar; the thrust block is provided between the thrust plate of the thrust shaft and the end of the collar; one end of the vibration isolation assembly extends from the collar and contacts the thrust block; an outer vibration isolation pad is provided on the contact surface between the thrust block and the collar; an outer cylindrical vibration isolation pad is provided on the outer peripheral surface of the thrust block, and the thrust block contacts the inner wall of the housing through the outer cylindrical vibration isolation pad. The beneficial effects of the present invention are as follows: the present invention arranges a radial vibration isolation structure between the radial support bearing and the shunting collar of the thrust bearing, which can attenuate the leakage of the longitudinal vibration energy of the shaft system through the radial support bearing, and can also realize the function of centering the inner shaft section within a limited angle.

Description

Technical Field

[0001] The invention relates to a ship shafting vibration isolation component, in particular to a thrust bearing vibration isolation structure. Background Art

[0002] The longitudinal vibration of the propeller shaft system is one of the main sources of low-frequency vibration noise at the stern, and is also the focus and difficulty of control in the field of ship acoustic design. The vibration isolation thrust bearing is an important device for controlling the longitudinal vibration of the propeller shaft system. The structural design of the vibration isolation thrust bearing plays an important role in improving the comfort of civil ships and enhancing the stealth performance of ships.

[0003] The vibration isolation structure is the core component of the vibration isolation thrust bearing, and is generally arranged in the thrust transmission channel inside the vibration isolation thrust bearing. A low-rigidity spring element is arranged inside the vibration isolation element, which transmits the longitudinal thrust of the propeller shaft system while isolating the vibration component therein, preventing it from being transmitted to the hull structure through the thrust bearing, and avoiding the problem of acoustic radiation caused by the coupling vibration of the propeller shaft and the boat. Compared with traditional thrust bearings, the insertion loss of the thrust bearing with a vibration isolation structure can reach ten decibels in the test frequency band.

[0004] The thrust bearing vibration isolation structure generally uses low-rigidity disc springs, rubber or coil springs as spring elements, and uses the low-rigidity characteristics of the spring elements to reduce the first-order natural frequency of the propeller shaft system, thereby changing the force transmission characteristics and achieving the purpose of longitudinal vibration reduction of the submarine shaft system. However, the existing vibration isolation thrust bearing design structure has certain energy leakage problems: 1) The thrust block is arranged circumferentially between the thrust plate and the collar, and due to the influence of gravity, it has rigid contact with the housing and the collar; 2) The support bearing is in close contact with the thrust shaft and bears the radial load of the shaft system. The above two contact points may cause part of the energy of the longitudinal vibration of the shaft system to bypass the vibration isolation structure and be directly transmitted from the contact point to the thrust bearing housing, causing a "short circuit phenomenon" in the transmission of the longitudinal vibration of the shaft system, which limits the vibration isolation effect of the vibration isolation thrust bearing. Summary of the invention

[0005] The purpose of the present invention is to provide a thrust bearing vibration isolation structure to solve the vibration "short circuit problem" inside the existing vibration isolation thrust bearing in view of the deficiencies in the prior art.

[0006] The technical solution adopted by the present invention is: a thrust bearing vibration isolation structure, including a thrust shaft, a shell, a thrust block, a support bearing and a collar; the shell is sleeved on the thrust shaft, and a head is provided at the end of the shell; the collar is installed inside the shell, and the two are arranged on the thrust shaft from the inside to the outside; a vibration isolation component is provided inside the collar; the thrust block is provided between the thrust plate of the thrust shaft and the end of the collar; one end of the vibration isolation component extends from the collar and contacts the thrust block; an outer vibration isolation pad is provided on the contact surface between the thrust block and the collar; an outer cylindrical vibration isolation pad is provided on the outer circumferential surface of the thrust block, and the thrust block contacts the inner wall of the shell through the outer cylindrical vibration isolation pad.

[0007] According to the above scheme, the inner side of the thrust block contacts the thrust plate of the thrust shaft through the first tile material layer, and the other side of the thrust block is inserted into the groove at the end of the ring. Lateral vibration isolation pads and inner circle vibration isolation pads are installed on the contact surface between the thrust block and the ring.

[0008] According to the above scheme, a radial vibration isolator is installed between the outer wall of the support bearing and the inner wall of the collar, and the two ends of the radial vibration isolator are respectively in contact with the thrust block and the adjustment pad.

[0009] According to the above scheme, a second bearing surface material layer is provided on the inner wall of the support bearing shell, and the support bearing shell is assembled on the thrust shaft through the second bearing surface material layer.

[0010] According to the above scheme, the vibration isolation assembly includes a cylinder body, a piston rod, a coil spring and an end cover; the cylinder body is arranged in a sleeve ring, and the rear end of the cylinder body is connected to the end cover; the piston rod and the coil spring are installed in the cylinder body, one end of the piston rod extends from the cylinder body and the sleeve ring, contacts the thrust block, transmits the thrust of the shaft system and attenuates the longitudinal vibration of the shaft system; the other end of the piston rod is connected to one end of the coil spring, and the other end of the coil spring is connected to the inner side of the end cover.

[0011] According to the above solution, a gap is left between the piston rod and the spring and the inner wall of the cylinder body.

[0012] According to the above solution, the radial vibration isolator is installed eccentrically, and the center of the inner hole of the radial vibration isolator is higher than the center line of the thrust shaft.

[0013] According to the above solution, the radial vibration isolator is made of oil-resistant rubber or composite material.

[0014] The beneficial effects of the present invention are as follows: the present invention sets a radial vibration isolation part between the radial support bushing of the thrust bearing and the front car ring, which can attenuate the leakage of the longitudinal vibration energy of the shaft system through the radial support bushing, and can also realize the function of aligning the shaft section within a limited angle; a vibration isolation pad is set on the mounting surface of the thrust block, and the thrust block is not in rigid contact with the housing and the ring, which can effectively avoid the direct transmission of the longitudinal vibration of the shaft system to the housing and the ring through the mounting surface of the thrust block; the piston rod of the vibration isolation component and the cylinder body retain a radial installation distance, and after being loaded, there will be no stick-slip effect of movement after rigid contact due to deformation, thereby avoiding weakening the vibration isolation effect of the longitudinal vibration; a bushing material layer is set between the support bushing and the thrust shaft, which reduces the friction between the support bushing and the thrust shaft, and reduces the conduction of the longitudinal vibration at this location. The above four designs improve the vibration "short circuit problem" inside the existing vibration isolation thrust bearing, avoid the energy leakage of the shaft system vibration at the mounting surface of the thrust block, and play an important role in optimizing the transmission path of the longitudinal vibration of the shaft system and further improving the vibration isolation capacity of the thrust bearing. The invention is applicable to ship propeller shaft systems, and is particularly applicable to submersibles with high acoustic requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of a specific embodiment of the present invention.

[0016] Figure 2 Schematic diagram of the structure of the vibration isolation assembly in this embodiment.

[0017] Figure 3 Schematic diagram of the structure of the thrust block in this embodiment.

[0018] Figure 4 for Figure 3 AA section view.

[0019] Among them: 1-thrust shaft; 2-thrust block; 3-ring; 4-vibration isolation assembly; 5-housing; 6-end oil seal; 7-support bearing; 8-radial vibration isolation member; 9-piston rod; 10-cylinder body; 11-helical spring; 12-end cover; 13-external vibration isolation pad; 14-lateral vibration isolation pad; 15-inner vibration isolation pad; 16-first bearing surface material layer; 17-head; 18-second bearing surface material layer; 19-adjustment pad. DETAILED DESCRIPTION

[0020] In order to better understand the present invention, the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0021] like Figure 1A thrust bearing vibration isolation structure shown in the figure comprises a thrust shaft 1, a shell 5, a thrust block 2, a support bearing 7 and a collar 3; the shell 5 is sleeved on the thrust shaft 1, and a head 17 is provided at the end of the shell 5 (the head 17 and the shell 5 can be welded as a whole); the collar 3 is installed inside the shell 5, and the two are arranged on the thrust shaft 1 from the inside to the outside; a vibration isolation component 4 is provided inside the collar 3; the thrust block 2 is provided between the thrust plate of the thrust shaft 1 and the end of the collar 3; one end of the vibration isolation component 4 extends from the collar 3 and contacts with the thrust block 2; an outer vibration isolation pad is provided on the contact surface between the thrust block 2 and the collar 3; an outer cylindrical vibration isolation pad 13 is provided on the outer peripheral surface of the thrust block 2, and the thrust block 2 contacts with the inner wall of the shell 5 through the outer cylindrical vibration isolation pad.

[0022] Preferably, the inner side of the thrust block 2 contacts the thrust disk of the thrust shaft 1 through the first tile material layer 16, and the other side of the thrust block 2 is inserted into the slot at the end of the collar 3. A lateral vibration isolation pad 14 and an inner circle vibration isolation pad 15 are installed on the contact surface between the thrust block 2 and the collar 3. The number and arrangement of the thrust blocks 2 and the vibration isolation assembly 4 are consistent.

[0023] Preferably, a radial vibration isolator 8 is installed between the outer wall of the support bearing 7 and the inner wall of the collar 3, and the two ends of the radial vibration isolator 8 are in contact with the thrust block 2 and the adjustment pad respectively. The radial vibration isolator 8 is installed eccentrically, and the center of its inner hole is slightly higher than the center line of the thrust shaft 1. The eccentricity is equal to the displacement creep amount brought to the radial vibration isolator 8 by the radial load of the support bearing 7. The radial vibration isolator 8 can attenuate the leakage of the longitudinal vibration energy of the shaft system through the radial support bearing, and can also realize the function of centering the inner shaft section within a limited angle.

[0024] Preferably, a second bearing surface material layer 18 is provided on the inner wall of the support bearing 7 , and the support bearing 7 is assembled on the thrust shaft 1 through the second bearing surface material layer 18 .

[0025] Preferably, the vibration isolation assembly 4 includes a cylinder body 10, a piston rod 9, a coil spring 11 and an end cover 12; the cylinder body 10 is arranged in the collar 3, and the rear end of the cylinder body 10 is connected to the end cover 12; the piston rod 9 and the coil spring 11 are installed in the cylinder body 10, one end of the piston rod 9 extends from the cylinder body 10 and the collar 3, contacts with the thrust block 2, transmits the thrust of the shaft system and attenuates the longitudinal vibration of the shaft system; the other end of the piston rod 9 is connected to one end of the coil spring 11, and the other end of the coil spring 11 is connected to the inner side of the end cover 12.

[0026] Preferably, a gap is left between the piston rod 9 and the spring and the inner wall of the cylinder body 10 .

[0027] Example

[0028] like Figure 1An improved thrust bearing vibration isolation structure shown in the figure includes a thrust shaft 1, a thrust block 2, a collar 3, a vibration isolation assembly 4, a shell 5, an end face oil seal 6, a support bearing 7 and a radial vibration isolation member 8; the shell 5 is arranged at the outermost layer of the thrust bearing and is the mounting base of the vibration isolation structure, and a head 17 is provided at the end of the shell 5, and an end face oil seal 6 is installed outside the head 17; the collar 3 is arranged in the shell 5, and the radial vibration isolation member 8 and the support bearing 7 are installed in the collar 3 from the outside to the inside in sequence, and the thrust shaft 1 is assembled with the support bearing 7.

[0029] A plurality of (may be 6, 8 or 10) mounting holes are evenly distributed circumferentially inside the collar 3, and the vibration isolation assembly 4 is arranged in the mounting holes; the vibration isolation assembly 4 includes a piston rod 9, a cylinder body 10, a coil spring 11 and an end cover 12, one end of the piston rod 9 extends from the cylinder body 10 and the inside of the collar 3, contacts with the thrust block 2, transmits the thrust of the shaft system and attenuates the longitudinal vibration of the shaft system.

[0030] The thrust block 2 is arranged between the thrust disk and the collar 3 of the thrust shaft 1, and the number and arrangement of the thrust blocks 2 are consistent with the vibration isolation assembly 4. The thrust block 2 is provided with an outer circular vibration isolation pad 13, a lateral vibration isolation pad 14, an inner circular vibration isolation pad 15 and a tile surface material layer. One side of the thrust block 2 contacts the thrust disk of the thrust shaft 1 through the tile surface material layer, and a protrusion is formed in the middle of the other side of the thrust block 2. The protrusion is adapted to the groove at the end of the collar 3, and the protrusion contacts the collar 3 through the lateral vibration isolation pad 14 and the inner circular vibration isolation pad 15; the outer peripheral surface of the thrust block 2 is adapted to the inner wall of the shell 5 through the outer circular vibration isolation pad 13. The outer circular vibration isolation pad 13, the inner circular vibration isolation pad 15, and the lateral vibration isolation pad 14 are made of oil-resistant rubber or composite materials, and are fixed to the outer circular surface, inner circular surface and lateral mounting surface of the thrust block 2 by mechanical fasteners, vulcanization or strong glue.

[0031] The setting of the vibration isolation pad can prevent the direct transmission of the longitudinal vibration of the shaft system to the housing 5 and the collar 3 through the mounting surface of the thrust block 2, and prevent the energy leakage of the shaft system vibration at the mounting surface of the thrust block 2. Specifically, the outer cylindrical surface of the thrust block 2 is installed with an outer cylindrical vibration isolation pad 13 to prevent the thrust block 2 at the lower part of the thrust bearing from rigidly contacting with the mounting surface of the housing 5 under the action of gravity; the inner cylindrical surface is installed with an inner cylindrical vibration isolation pad 15 to prevent the thrust block 2 at the upper part of the thrust bearing from rigidly contacting with the mounting surface of the collar 3 under the action of gravity; and the lateral vibration isolation pads 14 are installed on both sides to prevent the thrust block 2 in the middle part of the thrust bearing from rigidly contacting with the mounting surface of the collar 3 under the action of gravity.

[0032] A radial vibration isolator 8 is arranged between the support bearing 7 and the collar 3. The radial vibration isolator 8 is made of oil-resistant rubber or composite material and is fixed in the inner hole of the collar 3 by mechanical fasteners, vulcanization or strong glue. The radial vibration isolator 8 is installed eccentrically, and the center of its inner hole is slightly higher than the center line of the thrust shaft 1. The eccentricity is equal to the displacement creep amount brought to the radial vibration isolator 8 by the radial load of the support bearing 7. This eccentric installation method can ensure the consistency between the actual axis and the theoretical axis after the thrust bearing is installed. On the one hand, the radial vibration isolator 8 can attenuate the leakage of the longitudinal vibration energy of the shaft system through the radial support bearing, and can also realize the function of centering the inner shaft section within a limited angle.

[0033] A second bearing surface material layer 18 is provided on the inner circumferential surface of the support bearing 7. The second bearing surface material layer 18 is made of reinforced polytetrafluoroethylene material and is fixed to the support bearing 7 by a brazing process. It has the advantages of higher load-bearing capacity and lower friction coefficient. It can reduce the friction between the support bearing 7 and the thrust shaft 1 and reduce the conduction of longitudinal vibration there.

[0034] The vibration isolation assembly 4 includes a piston rod 9, a cylinder body 10, a coil spring 11 and an end cover 12. Both ends of the coil spring 11 are fixed to the end cover 12 and the piston rod 9 by mechanical fastening or welding. The end cover 12 is installed at the end of the cylinder body 10 by bolt fasteners; the piston rod 9 installs and pre-tightens the coil spring 11 through the end structure of the cylinder body 10. After the vibration isolation assembly 4 is installed, the piston rod 9 and the coil spring 11 maintain a certain installation distance from the cylinder body 10 in the radial direction. This arrangement ensures that when the coil spring 11 is deformed by the thrust load, there is no rigid contact between the piston rod 9 and the cylinder body 10 in the radial direction, avoiding the vibration transmission short circuit caused by the direct contact between the piston rod 9 and the cylinder body 10.

[0035] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to replace some of the technical features therein with equivalents. However, any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A thrust bearing vibration isolation structure, characterized in that: It comprises a thrust shaft, a housing, a thrust block, a support bearing and a collar; the housing is sleeved on the thrust shaft, and a head is provided at the end of the housing; the collar is installed inside the housing, and the two are arranged on the thrust shaft from the inside to the outside; a vibration isolation assembly is provided inside the collar; the thrust block is provided between the thrust plate of the thrust shaft and the end of the collar; one end of the vibration isolation assembly extends from the collar and contacts the thrust block; an outer vibration isolation pad is provided on the contact surface between the thrust block and the collar; an outer circular vibration isolation pad is provided on the outer circumferential surface of the thrust block, and the thrust block contacts the inner wall of the housing through the outer circular vibration isolation pad; A radial vibration isolator is installed between the outer wall of the support bearing and the inner wall of the collar, and the two ends of the radial vibration isolator are respectively in contact with the thrust block and the adjustment pad; the radial vibration isolator is installed eccentrically, and the center of the inner hole of the radial vibration isolator is higher than the center line of the thrust shaft; the eccentricity is equal to the displacement creep amount brought to the radial vibration isolator by the radial load of the support bearing.

2. The thrust bearing vibration isolation structure according to claim 1, characterized in that: The inner side of the thrust block contacts the thrust plate of the thrust shaft through the first tile material layer, and the other side of the thrust block is clamped into the groove at the end of the collar. Lateral vibration isolation pads and inner circle vibration isolation pads are installed on the contact surface between the thrust block and the collar.

3. The thrust bearing vibration isolation structure according to claim 1, characterized in that: A second bearing surface material layer is provided on the inner wall of the support bearing, and the support bearing is assembled on the thrust shaft through the second bearing surface material layer.

4. The thrust bearing vibration isolation structure according to claim 1, characterized in that: The vibration isolation assembly includes a cylinder body, a piston rod, a coil spring and an end cover; the cylinder body is arranged in a sleeve ring, and the rear end of the cylinder body is connected to the end cover; the piston rod and the coil spring are installed in the cylinder body, one end of the piston rod extends from the cylinder body and the sleeve ring, contacts the thrust block, transmits the thrust of the shaft system and attenuates the longitudinal vibration of the shaft system; the other end of the piston rod is connected to one end of the coil spring, and the other end of the coil spring is connected to the inner side of the end cover.

5. The thrust bearing vibration isolation structure according to claim 4, characterized in that: A gap is left between the piston rod and the spring and the inner wall of the cylinder body.

6. The thrust bearing vibration isolation structure according to claim 1, characterized in that: The radial vibration isolator is made of oil-resistant rubber or composite material.

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