A composite elastic bushing

Abstract

This invention discloses a composite elastic bushing, comprising a sleeve and a bushing disposed inside the sleeve. The bushing is constructed by continuously spirally coiling a metal strip. Each bushing has a first coiled portion and a second coiled portion along the spiral coiling direction. The second coiled portions of two bushings can be rotatably coupled together along each other's second gaps, forming a single unit that is fitted onto a shaft. This invention relates to the field of bushing technology. This composite elastic bushing not only solves the problem of good axial buffering but insufficient radial buffering, but also achieves synergistic buffering of axial and radial forces, significantly improving the bushing's vibration resistance and impact resistance under complex and harsh working conditions, and effectively preventing sleeve damage and scrap due to excessive radial vibration.

Description

Technical Field

[0001] This invention relates to the field of bushing technology, specifically to a composite elastic bushing. Background Technology

[0002] In the field of mechanical transmission, bushings are widely used support and rotating components. Their core function is to reduce friction between the shaft and the supporting component and to withstand radial and axial loads. Currently, most common bushing products on the market are rigid, cylindrical structures, typically made of materials such as bronze, iron-based powder metallurgy, engineering plastics, or copper alloys. While these bushings have a simple structure, their rigidity lacks buffering capacity when subjected to external impacts, vibrations, or accidental collisions during operation, and can lead to seizing during use.

[0003] To address the issues of insufficient impact resistance and the tendency for shafts to seize up in rigid bushings, our company has developed a helical elastic bushing, the related technology of which is disclosed in invention patent application CN115263926A. This bushing is constructed from a continuously coiled helical metal strip. Utilizing the elasticity of the metal strip and the helical structure, it possesses elastic deformation capabilities in the radial direction and to a certain extent in the axial direction. When the equipment is subjected to external impact, the helical structure can undergo elastic deformation, absorbing and buffering part of the impact energy, thereby slowing down the transmission of impact to the shaft and effectively reducing the risk of shaft seizure.

[0004] However, during practical application and continuous research and development, it was found that this first-generation helical elastic bushing product still has certain limitations. For example, its elastic design mainly focuses on axial buffering, and its buffering effect is still insufficient in dealing with sudden, high-frequency radial vibrations or chatter that occur when the shaft rotates. When the shaft experiences sudden radial runout or severe chatter caused by lateral impact, the bushing cannot effectively absorb this radial energy, resulting in excessive stress on the bushing structure itself. Under long-term action, this can easily lead to accelerated wear or even damage to the sleeve, ultimately causing the entire bushing to fail and be scrapped. In view of this, this application proposes an improved second-generation product. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a composite elastic bushing that solves the problem that existing elastic bushings cannot absorb radial forces, leading to damage or failure, when faced with sudden radial runout of the shaft or severe vibration caused by lateral impact.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a composite elastic bushing, comprising a sleeve and a bushing disposed inside the sleeve, wherein the bushing is formed by continuously spirally coiling a metal strip, and a shaft is assembled inside the bushing. There are two bushings, each bushing having a first coiled portion and a second coiled portion formed along the spiral coiling direction. A second gap is formed between two adjacent spiral coils of the second coiled portion. The second coiled portions of the two bushings can be rotatably coupled together along the second gap of each other so that the two bushings form a whole and are sleeved on the shaft.

[0007] Preferably, the gap of the second slit is b, and the width of the spiral coil of the second curled portion is d, wherein b ≥ d.

[0008] Preferably, a first gap is formed between two adjacent spiral coils of the first coiled portion, and the gap of the first gap is a, where a < b.

[0009] Preferably, after the second curled portions of the two bushings are rotatably coupled together, a third gap is formed between two adjacent second curled portions, and the gap of the third gap is c, where c < a.

[0010] Preferably, the metal strip has pressure holes spaced at equal intervals on its inner and outer walls. The pressure holes on the inner and outer walls of the first curled portion form a first oil storage groove. After the second curled portions of the two bushings are rotatably coupled together, the pressure holes on their inner and outer walls and the pressure holes of the other side form a second oil storage groove.

[0011] Preferably, a retainer is provided between the bushing and the sleeve. The retainer includes a main cylinder located inside the sleeve and auxiliary cylinders located on both sides of the main cylinder. The auxiliary cylinders are movable axially at both ends of the main cylinder.

[0012] Preferably, the auxiliary cylinder is composed of several arc-shaped pieces surrounding it.

[0013] Preferably, the inner walls of both sides of the main cylinder are machined with inner slopes that gradually slope towards the center from the outside to the inside, and the outer walls of the auxiliary cylinder are machined with outer slopes that match the inner slopes, forming an oblique gap between the inner slopes and the outer slopes.

[0014] Preferably, the auxiliary cylinder body abuts against the first coiled portion, and the main cylinder body abuts against the two coupled second coiled portions.

[0015] Preferably, an assembly gap is formed between the two ends of the retainer and the sleeve, and a sealing ring is provided in the assembly gap.

[0016] The beneficial effects of this invention are as follows: By using the composite elastic bushing provided by this invention, compared with the prior art, a single bushing is designed with a first curled portion and a second curled portion with different curling gaps. Two bushings can be assembled together to form a composite bushing. The two second curled portions are rotated and coupled together to form a tight assembly. Under conventional loads and axial impacts, it provides the main support and a certain degree of axial elasticity. The first curled portions on both sides provide deformable space when the shaft is subjected to external impacts or vibrations, weakening the impact of radial vibrations on the bushing itself and the sleeve, and effectively absorbing axial impact energy. This composite elastic bushing not only solves the problem of good axial buffering but insufficient radial buffering in the first-generation product, but also achieves synergistic buffering of axial and radial forces, significantly improving the bushing's vibration resistance and impact resistance under complex and harsh working conditions, and effectively preventing sleeve damage and scrapping caused by excessive radial vibration.

[0017] Meanwhile, the split design of the cage not only effectively assists the two bushings, but also forms a grease injection path with the assembly clearance. After the grease is injected from the outside, it forms a lubrication pattern from the outside to the inside and from the middle to both sides, ensuring that the lubricating grease can penetrate more evenly and deeply into the various coiled layers of the bushing and the contact surface with the shaft. Attached Figure Description

[0018] Figure 1 This is an isometric view of the present invention;

[0019] Figure 2 This is the front view of the present invention;

[0020] Figure 3 This is an isometric view of a single bushing of the present invention;

[0021] Figure 4 For the present invention Figure 3 Main view;

[0022] Figure 5 This is a schematic diagram of the two bushings of the present invention after they are assembled together;

[0023] Figure 6 This is a schematic diagram of the cage structure of the present invention;

[0024] Figure 7 For the present invention Figure 2 Enlarged structural diagram at point A in the middle;

[0025] Figure 8 For the present invention Figure 5 Enlarged structural diagram at point B.

[0026] Explanation of the reference numerals in the figure:

[0027] 1. Sleeve, 2. Bushing, 3. Cage, 31. Main cylinder, 32. Auxiliary cylinder, 33. Inner slope, 34. Outer slope, 35. Oblique gap, 4. First curled part, 5. Second curled part, 6. First gap, 7. Second gap, 8. Pressing port, 9. Third gap, 10. Sealing ring, 11. Assembly gap. Detailed Implementation

[0028] To better explain and facilitate understanding of this invention, the following description is provided in conjunction with the appendix. Figure 1 - Appendix Figure 8 The present invention will be described in detail through specific embodiments. The present invention discloses a composite elastic bushing. During processing, the bushing has a first coiled portion and a second coiled portion formed along the helical coiling direction. A second gap is formed between two adjacent helical coils of the second coiled portion. The second coiled portions of two bushings can be rotatably coupled together along each other's second gaps, so that the two bushings form a whole and are fitted onto the shaft. Furthermore, a retainer is provided between the bushing and the sleeve. Through the combined use of the two bushings, the two second coiled portions provide the main support and a certain degree of axial elasticity; the first coiled portions on both sides provide deformable space when the shaft experiences external impact or vibration, weakening the impact of radial vibration on the bushing itself and the sleeve, and effectively absorbing axial impact energy, achieving synergistic buffering of axial and radial forces.

[0029] 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. Various changes can be made to the implementation schemes as long as the effects of the present invention can be achieved.

[0030] Those skilled in the art can connect the components in this case sequentially. The specific connection and operation sequence should refer to the working principle described below. The detailed connection methods are well-known technologies in the field. The working principle and process are mainly described below.

[0031] This application proposes a composite elastic bushing, including a sleeve 1 and a bushing 2 disposed inside the sleeve 1. The bushing 2 is constructed of a continuously spirally coiled metal strip made of spring steel. Unlike existing technologies, a retainer 3 is provided between the bushing 2 and the sleeve 1, and a shaft is assembled inside the bushing 2. The maximum outer diameter of the retainer 3 is equal to or less than the inner diameter of the sleeve 1. To facilitate the installation of the retainer 3, the sleeve 1 in this embodiment has a split structure, including a cylindrical body and end rings assembled on both sides of the cylindrical body. The inner diameter of the end rings is smaller than the inner diameter of the cylindrical body, and they are assembled as a whole using set screws. This split design facilitates the installation of the retainer 3. During assembly, the retainer 3 is first placed into the cylindrical body, and then the end rings are fixed on both sides of the cylindrical body using set screws.

[0032] In this embodiment, as Figures 2 to 5 As shown, the bushing 2 has a first coiled portion 4 and a second coiled portion 5 formed along the spiral coiling direction. During processing, a plate rolling machine is used to roll the metal strip into a metal cylinder. During the rolling process, the metal strip is first tightly rolled to form the first coiled portion 4, and then the metal strip is stretched and rolled to form the second coiled portion 5, so that a single bushing 2 has two different coiling gaps.

[0033] In this design, a first gap 6 is formed between two adjacent spiral coils of the first coiled part 4. The first gap 6 is used to allow lubricating oil to move along the axial direction of the bushing 2 and to seep into the interior of the bushing in the movement trajectory, which is equivalent to the function of the oil line in common copper bushing products. A second gap 7 is formed between two adjacent spiral coils of the second coiled part 5. This gap is used to assemble the two bushings 2 of this product into a single unit to form a composite bushing. Compared with the prior art, the composite bushing can improve the retaining effect of the shaft and absorb and reduce vibration and / or impact forces when the shaft is in a high-speed rotation state in the forward or reverse direction, thereby improving the anti-locking effect of the shaft.

[0034] This embodiment also discloses an exemplary assembly method for two bushings 2. The second curled portions 5 of the two bushings 2 can be spirally rotated along the second gap 7 of each other and finally coupled together so that the two bushings 2 form a whole and are fitted onto the shaft. At this time, after the two second curled portions 5 are rotated and coupled, they are located in the middle position of the entire composite bushing, providing the main positioning support for the shaft. The first curled portions are located on both sides, and the second curled portions 5 absorb the vibration or impact force during shaft operation and diffuse it to the first curled portions 4 on both sides and disperse it, reducing the damage to the bushings 2 caused by vibration.

[0035] For example, the gap of the first slit 6 is a, the gap of the second slit 7 is b, and the width of the spiral coil of the second coiled part 5 is d, where a < b and b ≥ d. Setting the gap of the second slit 7 to be greater than or equal to the width of the spiral coil of the second coiled part 5 allows the two bushings 2 to rotate smoothly into each other when the second coiled parts 5 are rotated and coupled together.

[0036] After the second coiled portions 5 of the two bushings 2 are rotated and coupled together, a third gap 9 is formed between adjacent second coiled portions 5. The gap of the third gap 9 is c, where c < a. After the two bushings 2 are assembled, the small third gap 9 makes the second coiled portions 5 of the two bushings 2 form a whole, close to a complete cylindrical structure, providing a stable circumferential support force for the shaft. At the same time, it also has the elastic effect of a spiral structure, ensuring that the two coupled second coiled portions 5 can reduce the impact force on the pin when subjected to external impact force, preventing the pin from seizing.

[0037] In this embodiment, the two bushings 2 are rotatably coupled together to form a whole. During use, they are wrapped around the shaft and located in the sleeve 1. The two second coiled parts 5 are rotatably coupled together to form a fixed support end, and the first coiled parts 4 on both sides form two movable support ends. When the shaft is subjected to external impact, the fixed support end absorbs part of the shaft's vibration force and / or impact force, and transmits part of the vibration force and / or impact force to both sides for dispersion by the first coiled parts 4. At the same time, since the shaft is in a high-speed rotation state in the forward or reverse direction, when it vibrates due to vibration force and / or impact force, the movable support end expands and deforms. As the vibration force of the shaft gradually decreases, it tightens and retracts to the normal state through the synergistic action of the fixed support end and the movable support end, effectively preventing the shaft from seizing up.

[0038] Furthermore, in this embodiment, pressure holes 8 are equally spaced on the inner and outer walls of the metal strip. The pressure holes 8 are formed in the same way as those used in the prior art, specifically by using a rolling grooving device to perform unilateral equidistant grooving on the metal strip. The pressure holes 8 on the inner and outer walls of the first coiled portion 4 form a first oil reservoir. At the same time, after the second coiled portions 5 of the two bushings 2 are rotatably coupled together, the pressure holes 8 on the inner and outer walls of the two bushings 2 form a second oil reservoir with the pressure holes 8 of the other side. After adding lubricating oil, the lubricating oil slowly flows in the first gap 6 and the third gap 9 under the action of heating, vibration and capillary action when the two bushings 2 are working, and is stored in the first oil reservoir and the second oil reservoir, penetrating inward and contacting the outer wall of the shaft.

[0039] Reference Figure 2 and Figure 6 and Figure 7 This embodiment discloses a retainer 3 adapted to the aforementioned composite bushings, comprising a main cylinder 31 located within the sleeve 1 and auxiliary cylinders 32 located on both sides of the main cylinder 31. The auxiliary cylinders 32 are axially movable at both ends of the main cylinder 31. The auxiliary cylinders 32 abut against the first coiled portion 4, and the main cylinder 31 abuts against two coupled second coiled portions 5. For example, the fixed support end is located inside the main cylinder 31, and the movable support end is located inside the auxiliary cylinder 32, allowing the assembled two bushings 2 to be confined within the sleeve 1 and preventing direct contact between the two bushings 2 and the sleeve 1. This effectively avoids damage to the sleeve 1 caused by the deformation of the bushings 2 due to shaft vibration.

[0040] The auxiliary cylinder 32 is composed of several arc-shaped plates, such as two semi-circular plates or three or more arc-shaped plates, preferably two semi-circular plates, to accommodate the expansion deformation of the first curled section 4. For example, when the shaft vibrates due to vibration and / or impact, the first curled section 4 expands and deforms. At this time, multiple plates expand outward in the circumference of the first curled section 4 to accommodate the expansion deformation and retraction of the first curled section 4.

[0041] Furthermore, the inner walls of both sides of the main cylinder 31 are machined with inner slopes 33 that gradually slope towards the center from the outside in, and the outer wall of the auxiliary cylinder 32 is machined with outer slopes 34 that match the inner slopes 33. Through the cooperation of the inner slopes 33 and the outer slopes 34, the auxiliary cylinder 32 can move outward along the slope when the first curled part 4 expands and deforms, ensuring that the first curled part 4 can deform and work normally within the sleeve 1. At the same time, since the first curled part 4 and the auxiliary cylinder 32 are pressed together, when the first curled part 4 resets, it simultaneously drives the auxiliary cylinder 32 to retract and reset along the slope.

[0042] An oblique gap 35 is formed between the inner slope surface 33 and the outer slope surface 34. An assembly gap 11 is formed between the two ends of the retainer 3 and the sleeve 1. The oblique gap 35 and the assembly gap 11 are connected to form an oil passage for adding lubricating oil to the bushing 2. The assembly gap 11 is filled with grease and is provided with a sealing ring 10. The sealing ring 10 is used to seal the assembly gap 11 and can also support the auxiliary cylinder 32.

[0043] In actual operation, because the shaft is in continuous motion, it constantly generates vibration force or equipment parts vibrate due to bumps. The normal operation of the first coiled part 4 is to continuously expand and retract. The auxiliary cylinder 32 also continuously moves back and forth on the inner slope 33, following the expansion and retraction of the first coiled part 4. Therefore, the grease in the assembly gap 11 flows into the inner side of the main cylinder 31 through the inclined gap 35, following the reciprocating movement of the auxiliary cylinder 32, and contacts the second coiled part 5 of the two bushings 2. During the continuous rotation of the shaft and the transmission and dispersion of vibration force and / or impact force to the first coiled parts 4 on both sides, the grease flows along the third gap 9 to the first gap 6 and is stored in the first oil reservoir and the second oil reservoir. It also penetrates inward and contacts the outer wall of the shaft, forming a path for grease to be added from the outside to the inside within the retainer 3, and a method of adding grease from the middle to both sides on the two bushings 2, forming an oil circuit to ensure the uniform distribution of grease.

[0044] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A composite elastic bushing, comprising a sleeve and a bushing disposed inside the sleeve, wherein the bushing is formed by continuously spirally coiling a metal strip, and a shaft is assembled inside the bushing, characterized in that: There are two bushings. Each bushing has a first curled part and a second curled part along the spiral curling direction. A second gap is formed between two adjacent spiral coils of the second curled part. The second curled parts of the two bushings can be rotatably coupled together along the second gap of each other so that the two bushings form a whole and are sleeved on the shaft. The gap of the second slit is b, and the width of the spiral coil of the second curled part is d, where b ≥ d; A first gap is formed between two adjacent spiral coils of the first coiled portion, and the gap of the first gap is a, where a < b; After the second curled portions of the two bushings are rotated and coupled together, a third gap is formed between two adjacent second curled portions, and the gap of the third gap is c, where c < a; A retainer is provided between the bushing and the sleeve. The retainer includes a main cylinder located inside the sleeve and auxiliary cylinders located on both sides of the main cylinder. The auxiliary cylinders are capable of moving axially at both ends of the main cylinder.

2. The composite elastic bushing according to claim 1, characterized in that: The metal strip has pressure holes spaced at equal intervals on its inner and outer walls. The pressure holes on the inner and outer walls of the first curled part form a first oil storage groove. After the second curled parts of the two bushings are rotated and coupled together, the pressure holes on their inner and outer walls and the pressure holes of the other side form a second oil storage groove.

3. The composite elastic bushing according to claim 1, characterized in that: The auxiliary cylinder is composed of several arc-shaped pieces surrounding it.

4. The composite elastic bushing according to claim 1, characterized in that: The inner walls of both sides of the main cylinder are machined with an inner slope that gradually slopes towards the center from the outside to the inside, and the outer wall of the auxiliary cylinder is machined with an outer slope that matches the inner slope. An oblique gap is formed between the inner slope and the outer slope.

5. A composite elastic bushing according to claim 1, characterized in that: The auxiliary cylinder abuts against the first coiled section, and the main cylinder abuts against the two coupled second coiled sections.

6. The composite elastic bushing according to claim 1, characterized in that: An assembly gap is formed between the two ends of the retainer and the sleeve, and a sealing ring is provided in the assembly gap.

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