A multi-sealed drive shaft

Abstract

This invention relates to the field of transmission technology, specifically to a multi-sealed transmission shaft. The transmission shaft includes a shaft fork assembly, a steering assembly, and an outer sealing assembly. The steering assembly includes a cross unit, a rotating sleeve unit, and an inner sealing unit. In the cross unit, one end of the cross shaft is connected to the cross seat, and the other end extends away from the cross seat; four cross shafts are spaced apart circumferentially along the cross seat. The rotating sleeve unit and the inner sealing unit are sequentially fitted onto the outer periphery of the cross shaft; each pair of rotating sleeve units is connected to both ends of the first fork unit and the second fork unit of the shaft fork assembly, respectively. In the outer sealing assembly, a hollow outer shell unit has four clearance holes circumferentially arranged; the outer shell unit encloses the cross seat; one cross shaft passes through one clearance hole; a soft sleeve is fitted onto the outer periphery of the rotating sleeve unit; both ends of the soft sleeve are connected to the rotating sleeve unit and the outer shell unit, respectively. This solves the problem of rapid aging and failure of the universal joint's sealing components in harsh environments.

Description

Technical Field

[0001] This invention relates to the field of transmission technology, and more specifically, to a multi-sealed transmission shaft. Background Technology

[0002] Drive shafts are used to transmit torque in mechanical transmission systems. When the centerlines of the components transmitting torque do not coincide, universal joints are typically used to achieve angular misalignment to ensure effective power transmission. The sealing components of a universal joint prevent the intrusion of external dust, moisture, and impurities, while also preventing internal lubricant leakage, which is crucial for the normal operation and service life of the universal joint. When used in harsh environments (such as rain, mud, and foreign objects), the universal joint's sealing components are exposed to the outside, making them susceptible to aging and failure due to dust, moisture, and temperature changes. Existing technologies typically attempt to enhance the sealing effect and improve the durability of the sealing components in harsh environments by improving the sealing lip structure, such as increasing the number of sealing lips, optimizing the sealing lip shape, or selecting specific materials.

[0003] However, dust, moisture, and other impurities gradually penetrate through the gap between the sealing lip and the rotating shaft. Long-term accumulation exacerbates lip wear, while drastic temperature changes lead to a decline in the physical properties of the sealing material, accelerating the aging process. These factors combined mean that measures to improve the sealing lip structure have limited effectiveness and cannot fundamentally solve the problem of aging and failure of sealing components under harsh environments. Summary of the Invention

[0004] To address the problem of rapid aging and failure of universal joint sealing components in harsh environments, this invention provides a multi-sealed drive shaft, comprising:

[0005] A fork assembly, the fork assembly including a first fork unit and a second fork unit;

[0006] A steering assembly includes a cross unit, a rotating sleeve unit, and an inner sealing unit. The cross unit includes a cross seat and four cross shafts. One end of each cross shaft is connected to the cross seat, and the other end extends away from the cross seat. The four cross shafts are spaced apart circumferentially from the cross seat. A portion of the inner circumferential wall of one rotating sleeve unit abuts against and is rotatably connected to the outer circumferential wall of one of the cross shafts. An inner sealing unit is sleeved on the outer circumferential side of one of the cross shafts. A side wall of the inner sealing unit, the inner circumferential wall of the rotating sleeve unit, and the outer circumferential wall of the cross shafts enclose and form a sealed rotating chamber. Two rotating sleeve units are respectively connected to both ends of a first fork unit. The remaining two rotating sleeve units are respectively connected to both ends of a second fork unit. Between the two rotating sleeve units connected to the first fork unit, there is one rotating sleeve unit connected to the second fork unit.

[0007] An external sealing assembly includes a housing unit and four flexible sleeves. The housing unit is a hollow shell. Four clearance holes are provided around the circumference of the housing unit. The housing unit encloses and connects to the cross seat. One cross shaft passes through one clearance hole of the housing unit. One flexible sleeve is fitted around the outer periphery of a rotating sleeve unit. One end of the flexible sleeve is connected to the rotating sleeve unit, and the other end is connected to the housing unit. The four flexible sleeves, the housing unit, and the four rotating sleeve units surround and form a sealed protective chamber. Four inner sealing units are disposed within the protective chamber.

[0008] In some embodiments, the outer casing unit includes two half-shells, four clearance holes, four second engagement slots, and four second retaining rings; the two half-shells are symmetrically spaced along a central plane; the two half-shells are at least partially circumferentially connected, forming four clearance holes spaced circumferentially along the half-shells; one second engagement slot is disposed on the two half-shells; one second engagement slot is concentrically disposed with at least one clearance hole; one end of the soft sleeve is connected to the half-shells through the engagement of the second retaining rings and the second engagement slot.

[0009] In some embodiments, the rotating sleeve unit includes a rotating sleeve body, a rolling element, a first engaging groove, and a first retaining spring; the rotating sleeve body is sleeved on the outer peripheral side of the cross shaft; the rolling element is disposed in the circumferential space between the rotating sleeve body and the cross shaft; the rolling element abuts against the inner peripheral wall of the rotating sleeve body and the outer peripheral wall of the cross shaft respectively; the first engaging groove is disposed on the outer peripheral wall of the rotating sleeve body; one end of the soft sleeve body away from the second engaging groove is connected to the rotating sleeve body through the engagement of the first retaining spring and the first engaging groove.

[0010] In some embodiments, the housing unit further includes four extension sleeves; one end of each extension sleeve is connected to the half-shell, and the other end extends away from the half-shell; one of the extension sleeves is fitted onto the outer periphery of a soft sleeve.

[0011] In some embodiments, the projection of the extension sleeve onto the rotating body covers the first engagement groove.

[0012] In some embodiments, the multi-sealed drive shaft further includes a filler; the housing unit further includes a filling nozzle; the filling nozzle is connected to the semi-housing; the multi-sealed drive shaft includes a filled state and a sealed state; the filled state includes the fillinger being injected into the protective chamber through the filling nozzle; the sealed state includes the filling nozzle being closed, and the protective chamber being cut off from external space.

[0013] In some embodiments, the rotating chamber is filled with the filler.

[0014] In some embodiments, the filler in the protective chamber compresses the soft sleeve and expands towards the inner peripheral wall of the extension sleeve, causing a portion of the outer peripheral wall of the soft sleeve to abut against the inner peripheral wall of the extension sleeve.

[0015] In some embodiments, the first fork unit includes a first fork seat, a first left fork arm, a first left fork hole, a first right fork arm, and a first right fork hole; one end of the first left fork arm is connected to the first fork seat, and the other end extends toward a first side of the first fork seat; one end of the first right fork arm is connected to the first fork seat, and the other end extends toward a first side of the first fork seat; the first left fork arm and the first right fork arm are spaced apart; the first left fork hole passes through the first left fork arm; the first right fork hole passes through the first right fork arm; the center line of the first left fork hole coincides with the center line of the first right fork hole; the two rotating sleeve units are respectively interference-fitted with the first left fork hole and the first right fork hole;

[0016] The second fork unit includes a second fork seat, a second left fork arm, a second left fork hole, a second right fork arm, and a second right fork hole; one end of the second left fork arm is connected to the second fork seat, and the other end extends toward the second side of the second fork seat; one end of the second right fork arm is connected to the second fork seat, and the other end extends toward the second side of the second fork seat; the second left fork arm and the second right fork arm are spaced apart; the second left fork hole passes through the second left fork arm; the second right fork hole passes through the second right fork arm; the center line of the second left fork hole coincides with the center line of the second right fork hole; the two rotating sleeve units are respectively interference-fitted with the second left fork hole and the second right fork hole.

[0017] In some embodiments, the fork assembly further includes a first shaft and a second shaft; one end of the first shaft is connected to the first fork unit, and the other end extends away from the second fork unit; one end of the second shaft is connected to the second fork unit, and the other end extends away from the first fork unit.

[0018] To address the problem of rapid aging and failure of universal joint sealing components in harsh environments, this invention offers the following advantages:

[0019] By setting an inner sealing unit in the steering assembly, which is fitted onto the outer periphery of the cross shaft, and with one side wall of the inner sealing unit, the inner periphery of the rotating sleeve unit, and the outer periphery of the cross shaft surrounding it to form a sealed rotating chamber, the connection between the cross shaft and the rotating sleeve unit can be sealed, preventing the exchange of external impurities and internal lubricating grease, thus forming a first layer of seal. Based on this, an outer sealing assembly is set, in which an outer shell unit wraps around and connects to the cross seat, and a soft sleeve is fitted onto the outer periphery of the rotating sleeve unit, with one end connected to the rotating sleeve unit and the other end connected to the outer shell unit. Four soft sleeves, the outer shell unit, and four rotating sleeve units surround and form a sealed protective chamber, and four inner sealing units are placed inside the protective chamber, thus forming a second layer of seal outside the rotating chamber, enclosing the inner sealing units and other components within the protective chamber. Because the soft sleeve can undergo elastic deformation within a certain angle range, it can effectively block external dust, moisture, impurities, etc. from entering the protective chamber while meeting the requirements of drive shaft angular deflection. This reduces their impact on the inner sealing unit of the protective chamber, thereby greatly increasing the sealing effect of the drive shaft, extending the service life of the inner sealing unit, and ultimately reducing the risk of aging and failure of universal joint sealing components in harsh environments. Attached Figure Description

[0020] Figure 1 A schematic diagram of a multi-sealed drive shaft structure according to one embodiment is shown;

[0021] Figure 2 It shows Figure 1 Front view of the multi-sealed drive shaft in the embodiment;

[0022] Figure 3 It shows Figure 2 A cross-sectional view (AA) of the multi-sealed drive shaft in the embodiment;

[0023] Figure 4 It shows Figure 1 Left view of the multi-sealed drive shaft in the embodiment;

[0024] Figure 5 It shows Figure 1 Right view of the multi-sealed drive shaft in the embodiment;

[0025] Figure 6 A schematic diagram of a steering assembly structure for a multi-sealed driveshaft according to one embodiment is shown;

[0026] Figure 7 It shows Figure 6 Top view of the steering component in the embodiment;

[0027] Figure 8 It shows Figure 7 A schematic BB cross-sectional view of the steering component in the embodiment;

[0028] Figure 9 It shows Figure 8 Enlarged view of region C in the BB cross-sectional schematic diagram of the embodiment.

[0029] Reference numerals: 10. Axle fork assembly; 11. First fork unit; 111. First fork seat; 112. First left fork arm; 113. First left fork hole; 114. First right fork arm; 115. First right fork hole; 12. Second fork unit; 121. Second fork seat; 122. Second left fork arm; 123. Second left fork hole; 124. Second right fork arm; 125. Second right fork hole; 13. First shaft; 14. Second shaft; 20. Steering assembly; 21. Cross unit; 211. Cross seat; 212. Cross shaft; 22. Sleeve unit; 221. Sleeve body; 222. Rolling element; 223. First engagement groove; 224. First retaining ring; 23. Inner sealing unit; 30. Outer sealing assembly; 31. Outer shell unit; 311. Half shell; 312. Clearance hole; 313. Second engagement groove; 314. Second retaining ring; 315. Filler nozzle; 316. Extension sleeve; 32. Soft sleeve body. Detailed Implementation

[0030] The present disclosure will now be discussed with reference to several exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present disclosure, and are not intended to imply any limitation on the scope of the disclosure.

[0031] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to". The term "based on" is to be interpreted as "at least partially based on". The terms "one embodiment" and "an embodiment" are to be interpreted as "at least one embodiment". The term "another embodiment" is to be interpreted as "at least one other embodiment". The terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments and are not intended to limit the indicated devices, elements, or components to having a specific orientation or being constructed and operated in a specific orientation. Furthermore, some of the above terms may be used to indicate other meanings besides orientations or positional relationships; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application according to the specific circumstances. In addition, the terms "installed", "set up", "equipped with", "connected", and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, elements, or components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. Furthermore, the terms "first," "second," etc., are mainly used to distinguish different devices, elements, or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.

[0032] In mechanical transmission systems, the drive shaft uses a universal joint to achieve angular deflection to accommodate situations where the center lines of the components on both sides do not coincide. In the steering assembly 20, the rotating sleeve unit 22 is rotatably connected to the cross shaft 212, and the inner sealing unit 23 is sleeved on the outer periphery of the cross shaft 212, forming a sealed rotating chamber with the rotating sleeve unit 22 and the cross shaft 212 to seal the rotating connection. However, in harsh environments, external dust, moisture, impurities, etc., can easily enter the rotating chamber through the sealing gap, and internal lubricating grease may leak, leading to a decrease in the sealing performance of the rotating chamber. In addition, temperature changes and mechanical vibrations in harsh environments can accelerate the aging of the material of the inner sealing unit 23, reducing its physical properties and sealing reliability. In the prior art, relying solely on the inner sealing unit 23 to seal the rotating chamber, the single sealing structure is insufficient to effectively resist the combined effects of multiple complex environmental factors, making the universal joint sealing component face a high risk of aging failure and failing to meet the requirements for the sealing performance and service life of the drive shaft in practical applications.

[0033] Example 1: In order to solve the above problems, this example discloses a multi-sealed drive shaft.

[0034] In this embodiment, as Figure 1 As shown, the multi-sealed drive shaft includes: a shaft fork assembly 10, a steering assembly 20, and an outer sealing assembly 30. (As shown...) Figure 2 As shown, the shaft fork assembly 10 includes a first fork unit 11 and a second fork unit 12. The first fork unit 11 extends fork arms to both sides with one end as the center, forming a "U-shaped" fork structure. The second fork unit 12 is mirror-symmetrical to the first fork unit 11. Figure 3 , Figure 6 , Figure 7 , Figure 8As shown, the steering assembly 20 includes a cross unit 21, a rotating sleeve unit 22, and an inner sealing unit 23. The cross unit 21 includes a cross seat 211 and four cross shafts 212. One end of each cross shaft 212 is connected to the cross seat 211, and the other end extends away from the cross seat 211. The cross shaft 212 and the cross seat 211 are integrally formed, and the cross shaft 212 can be cylindrical. The four cross shafts 212 are spaced apart circumferentially along the cross seat 211, that is, two cross shafts 212 are symmetrically arranged on the cross seat 211 in a cross shape. The inner peripheral wall of a rotating sleeve unit 22 abuts against and is rotatably connected to the outer peripheral wall of a cross shaft 212, that is, the rotating sleeve unit 22 is sleeved on the cross shaft 212. It is a hollow cylindrical tube open at one end; an inner sealing unit 23 is fitted onto the outer periphery of a cross shaft 212; a side wall of the inner sealing unit 23, the inner peripheral wall of the rotating sleeve unit 22, and the outer peripheral wall of the cross shaft 212 surround and form a sealed rotating chamber. The inner sealing unit 23, also known as a sealing ring, can prevent the leakage of lubricating grease in the rotating chamber or the entry of foreign objects; two rotating sleeve units 22 are respectively connected to both ends of the first fork unit 11; the remaining two rotating sleeve units 22 are respectively connected to both ends of the second fork unit 12; there is a rotating sleeve unit 22 connected to the second fork unit 12 between the two rotating sleeve units 22 connected to the first fork unit 11; the connection method is a detachable connection, which can be an interference fit, a snap-fit ​​connection, a threaded connection, etc. The rotating sleeve unit 22 and the cross unit 21 allow the first fork unit 11 and the second fork unit 12 to transmit torque to each other. Figure 6 , Figure 7 , Figure 8 , Figure 9 As shown, the outer sealing assembly 30 includes an outer shell unit 31 and four soft sleeves 32. The outer shell unit 31 is configured as a hollow shell, and the outer shell unit 31 can be a conformal shell such as rubber or plastic. Four clearance holes 312 are provided around the outer shell unit 31. The outer shell unit 31 covers the cross seat 211 and is connected to the cross seat 211 in a detachable connection manner. The outer shell unit 31 can protect the cross seat 211 from erosion by rainwater, foreign objects, etc. A cross shaft 212 passes through one clearance hole 312 of the outer shell unit 31. A soft sleeve 32 is fitted on the outer periphery of a rotating sleeve unit 22. One end of the soft sleeve 32 is connected to the rotating sleeve unit 22, and the other end is connected to the outer shell unit 31. The four soft sleeves 32, the outer shell unit 31, and the four rotating sleeve units 22 surround and form a sealed protective chamber. Four inner sealing units 23 are disposed in the protective chamber. When the first fork unit 11 and the second fork unit 12 transmit torque, there will be relative displacement between the rotating sleeve unit 22 and the cross shaft 212, and the rotating sleeve unit 22 will swing within a certain angle range, such as between 30° and 50°. Therefore, a soft sleeve 32 that can undergo a certain elastic deformation is needed to wrap around the periphery of the end of the rotating sleeve unit 22 near the cross shaft 212 to form a secondary seal.

[0035] Through the above structure, the inner sealing unit 23, the rotating sleeve unit 22, and the cross shaft 212 can form a sealed rotating chamber, achieving the first layer of sealing at the connection between the cross shaft 212 and the rotating sleeve unit 22; at the same time, the outer shell unit 31 and the soft sleeve 32 form a sealed protective chamber, slowing down the aging of the cross seat 211 while wrapping the inner sealing unit 23 to form a second layer of sealing. The soft sleeve 32 can be made of flexible materials, such as latex or rubber, and its own elastic deformation capability can meet the requirements of the drive shaft angle deflection. The two-layer sealing structure can effectively prevent the intrusion of external dust, moisture, and impurities, reduce the leakage of internal lubricating grease, thereby greatly increasing the sealing effect of the drive shaft and extending the service life of the inner sealing unit 23.

[0036] Furthermore, such as Figure 7 , Figure 8 , Figure 9 As shown, the outer shell unit 31 includes two half-shells 311, four clearance holes 312, four second engagement grooves 313, and four second retaining springs 314. The two half-shells 311 are symmetrically spaced along the central plane, and both half-shells 311 adopt a contoured structure to fit the cross unit 21. The two half-shells 311 are at least partially connected on their periphery, forming four clearance holes 312 spaced apart along the circumference of the half-shells 311. The two half-shells 311 can be connected by fitting, snap-fit ​​connection, threaded connection, etc. A second engagement groove 313 is provided on the two half-shells 311. The second engagement groove 313 is formed by the recess of the inner wall of the half-shell 311 and is circular in shape. At least one second engagement groove 313 is concentrically arranged with one clearance hole 312. One end of the soft sleeve 32 is connected to the half-shell 311 through the engagement of the second retaining springs 314 and the second engagement groove 313. The above structure allows the two half-shells 311 to be symmetrically arranged and connected along the central plane, facilitating the installation and removal of the outer shell unit 31 outside the cross seat 211. The clearance hole 312 provides a passage for the cross shaft 212, facilitating the assembly of the cross shaft 212 with the rotating sleeve unit 22. The soft sleeve 32 achieves quick connection and separation from the outer shell unit 31 through the snap-fit ​​structure of the second snap ring 314 and the second snap-fit ​​groove 313. This design simplifies the installation process of the outer sealing assembly 30, reduces the difficulty of disassembly during maintenance, and improves the convenience of component replacement.

[0037] Furthermore, such as Figure 7 , Figure 8 , Figure 9As shown, the rotating sleeve unit 22 includes a rotating sleeve body 221, a rolling element 222, a first engaging groove 223, and a first retaining spring 224. The rotating sleeve body 221 is sleeved on the outer peripheral side of the cross shaft 212. The rolling element 222 is disposed in the circumferential space between the rotating sleeve body 221 and the cross shaft 212. The rolling element 222 can be a ball or a roller. The rolling element 222 abuts against the inner peripheral wall of the rotating sleeve body 221 and the outer peripheral wall of the cross shaft 212, respectively. The first engaging groove 223 is disposed on the outer peripheral wall of the rotating sleeve body 221. The first engaging groove 223 is formed by a recess in the outer peripheral wall of the rotating sleeve body 221 near the half shell 311. The end of the soft sleeve 32 away from the second engaging groove 313 is connected to the rotating sleeve body 221 through the engagement of the first retaining spring 224 and the first engaging groove 223. With the above structure, the rolling element 222 can be positioned between the rotating sleeve 221 and the cross shaft 212, converting sliding friction into rolling friction and reducing wear during relative rotation. The soft sleeve 32 is detachably connected to the rotating sleeve 221 by engaging with the first snap ring 224 and the first engaging groove 223. The soft sleeve 32 is made of flexible material and can elastically deform with changes in angle when the rotating sleeve 221 rotates, forming a dynamic seal that effectively protects the sealing performance of the internal rotating chamber. At the same time, the snap-fit ​​structure facilitates the disassembly and replacement of the soft sleeve 32, extending the service life of the steering assembly 20.

[0038] Furthermore, such as Figure 7 , Figure 8 , Figure 9 As shown, the outer casing unit 31 also includes four extension sleeves 316; one end of each extension sleeve 316 is connected to the half-shell 311, and the other end extends away from the half-shell 311. The extension sleeve 316 can be integrally formed with the half-shell 311 or detachably connected to it. One extension sleeve 316 is fitted onto the outer periphery of a flexible sleeve 32. Through this structure, the extension sleeve 316 can wrap around the outside of the flexible sleeve 32, providing external support and protection for the flexible sleeve 32 made of flexible material, preventing sharp objects or mechanical stress from directly acting on the surface of the flexible sleeve 32, and reducing the risk of wear and damage to its outer surface. Simultaneously, the connection between the extension sleeve 316 and the outer casing unit 31 can further strengthen the sealing structure of the protective chamber, improve the overall sealing effect, and extend the service life of the flexible sleeve 32.

[0039] Furthermore, such as Figure 9As shown, the projection of the extension sleeve 316 onto the rotating sleeve 221 covers the first engagement groove 223. This structure allows the length of the extension sleeve 316 to precisely match the position of the first engagement groove 223 on the rotating sleeve 221. This avoids interference during installation of the axle fork assembly 10 due to the extension sleeve 316 being too long, and also prevents the extension sleeve 316 from being too short to cover the connection area between the soft sleeve 32 and the rotating sleeve 221. This ensures effective protection of the soft sleeve 32 by the extension sleeve 316, while not affecting the assembly accuracy of the steering assembly 20 and the axle fork assembly 10.

[0040] In other embodiments, such as Figure 8 As shown, the multi-sealed drive shaft also includes a filler, which can be lubricating grease; the housing unit 31 also includes a filling nozzle 315; the filling nozzle 315 is connected to the half-shell 311, and the filling nozzle 315 is a valve for injecting grease, which can be detachably connected to the half-shell 311, and its installation position can be the peripheral side wall of the half-shell 311 or the geometric center of the half-shell 311; the multi-sealed drive shaft includes a filled state and a sealed state; the filled state includes the filling of the filler into the protective chamber through the filling nozzle 315; the sealed state includes the filling nozzle 315 being closed, cutting off the communication between the protective chamber and the external space. With the above structure, in the filled state, grease or other fillers can be injected into the protective chamber through the filling nozzle 315, and the filler can squeeze out the air in the protective chamber, reduce the internal gap, and enhance the sealing effect; at the same time, the filler can provide lubrication for the moving parts in the protective chamber, reduce friction loss, and absorb the heat generated by the friction between the outer sealing assembly 30 and the steering assembly 20, avoiding local overheating and material aging, thereby extending the service life of the outer sealing assembly 30.

[0041] Furthermore, the rotating chamber is filled with a filler. Through the above structure, the filler (such as grease) can fill the rotating chamber, providing a lubricating medium for both the cross shaft 212 and the rotating sleeve unit 22 when they rotate relative to each other. This reduces wear caused by direct contact between metal parts, lowers frictional resistance, improves rotational smoothness, and thus extends the service life of the internal components of the rotating chamber.

[0042] Furthermore, the filling material within the protective chamber compresses the soft sleeve 32, causing it to expand towards the inner peripheral wall of the extension sleeve 316, resulting in a portion of the outer peripheral wall of the soft sleeve 32 abutting against the inner peripheral wall of the extension sleeve 316. For example... Figure 8 , Figure 9As shown, since the second engaging groove 313 is located on the inner peripheral wall of the outer shell unit 31 and the first engaging groove 223 is located on the outer peripheral wall of the rotating sleeve 221, the cross section of the soft sleeve 32 is inclined. That is, one end of the soft sleeve 32 is close to the inner wall of the outer shell unit 31 and the other end is close to the outer wall of the rotating sleeve 221. With the above arrangement, the squeezing action of the filler can cause the soft sleeve 32 to expand towards the inner peripheral wall of the extension sleeve 316. The outer surface of the soft sleeve 32 on the side close to the second engaging groove 313 first abuts against the extension sleeve 316. The soft sleeve 32 on the side close to the second engaging groove 313 has a larger degree of bending deformation due to the snap spring connection, which is prone to stress concentration. The soft sleeve 32 that abuts against the extension sleeve 316 after being squeezed and expanded by the filler can limit the displacement in this area, reduce the relative movement between the soft sleeve 32 and the rotating sleeve unit 22, thereby reducing the wear risk of the soft sleeve 32 in the high stress area and extending its service life.

[0043] Furthermore, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5As shown, the first fork unit 11 includes a first fork seat 111, a first left fork arm 112, a first left fork hole 113, a first right fork arm 114, and a first right fork hole 115; one end of the first left fork arm 112 is connected to the first fork seat 111, and the other end extends toward the first side of the first fork seat 111; one end of the first right fork arm 114 is connected to the first fork seat 111, and the other end extends toward the first side of the first fork seat 111; the first left fork arm 112 and the first right fork arm 114 are spaced apart; the first left fork hole 113 passes through the first left fork arm 112; wherein, the first fork seat 111 is the core connecting component of the axle fork assembly 10, used to support and transmit torque; the first left fork arm 112 and the first right fork arm 114 are distributed in a "U" shape on both sides of the first fork seat 111, forming the fork-shaped structure of the first fork unit 11, providing an installation position for the swivel unit 22. The first right fork hole 115 passes through the first right fork arm 114; the center line of the first left fork hole 113 coincides with the center line of the first right fork hole 115. The coincidence of the center lines of the fork holes ensures the coaxiality of the rotating sleeve unit 22, making the torque transmission more stable and reducing wear and energy loss caused by installation deviation; the two rotating sleeve units 22 are respectively interference-fitted with the first left fork hole 113 and the first right fork hole 115, so that the first fork unit 11 can be rotatably connected to the cross shaft 212 through the rotating sleeve unit 22, realizing the transmission of torque and the angular deflection. The second fork unit 12 includes a second fork seat 121, a second left fork arm 122, a second left fork hole 123, a second right fork arm 124, and a second right fork hole 125. One end of the second left fork arm 122 is connected to the second fork seat 121, and the other end extends toward the second side of the second fork seat 121. One end of the second right fork arm 124 is connected to the second fork seat 121, and the other end extends toward the second side of the second fork seat 121. The second left fork arm 122 and the second right fork arm 124 are spaced apart. The second fork seat 121 is the core support component of the second fork unit 12 and is structurally symmetrical with the first fork seat 111. The second left fork arm 122 and the second right fork arm 124 are symmetrically distributed on both sides of the second fork seat 121, forming a fork-shaped structure mirrored with the first fork unit 11. The second left fork hole 123 passes through the second left fork arm 122; the second right fork hole 125 passes through the second right fork arm 124; the center line of the second left fork hole 123 coincides with the center line of the second right fork hole 125; the two rotating sleeve units 22 are respectively interference-fitted with the second left fork hole 123 and the second right fork hole 125. When the first fork unit 11 and the second fork unit 12 are assembled with the steering assembly 20, the first center line between the first left fork hole 113 and the first right fork hole 115 intersects with the second center line between the second left fork hole 123 and the second right fork hole 125. When the first fork unit 11 and the second fork unit 12 transmit torque to each other, the rotating sleeve unit 22 and the outer shell unit 31 will generate relative displacement along the circumference of the cross shaft 212, and wobble within a certain angle range, so that the central axis of the first fork unit 11 and the central axis of the second fork unit 12 form an angle, thereby changing the direction of the transmitted torque.The yaw angle can range from 30 degrees to 50 degrees.

[0044] With the above structure, the first fork unit 11 and the second fork unit 12 can be connected to the rotating sleeve unit 22 by an interference fit to form a rigid transmission node. When the drive shaft transmits torque, the first fork unit 11 and the second fork unit 12 can be rotatably connected to the cross unit 21 through the rotating sleeve unit 22, which can change the direction of torque transmission, meet the power transmission requirements of angular wobble between different components in the mechanical transmission system, and ensure the effective transmission of torque between non-coaxial components.

[0045] Furthermore, such as Figure 1 As shown, the shaft fork assembly 10 also includes a first shaft 13 and a second shaft 14. One end of the first shaft 13 is connected to the first fork unit 11, and the other end extends away from the second fork unit 12. One end of the second shaft 14 is connected to the second fork unit 12, and the other end extends away from the first fork unit 11. The first shaft 13 and the second shaft 14 can be cylindrical long shafts or short shafts. With the above structure, the first shaft 13 and the second shaft 14 can serve as the power input and output ends, respectively, connecting the first fork unit 11 and the second fork unit 12 to the corresponding components of the mechanical transmission system, forming a complete torque transmission path. The first shaft 13 and the second shaft 14, through the cooperation of the steering assembly 20 and the outer sealing assembly 30, maintain sealing performance while adapting to angular wobble, thereby achieving stable torque transmission during mechanical transmission.

[0046] Those skilled in the art will understand that the above embodiments are specific examples of implementing this disclosure, and in practical applications, various changes can be made in form and detail without departing from the scope of this disclosure.

Claims

1. A multi-sealed drive shaft, characterized in that, The multi-sealed drive shaft includes: A fork assembly, the fork assembly including a first fork unit and a second fork unit; A steering assembly includes a cross unit, a rotating sleeve unit, and an inner sealing unit. The cross unit includes a cross seat and four cross shafts. One end of each cross shaft is connected to the cross seat, and the other end extends away from the cross seat. The four cross shafts are spaced apart circumferentially from the cross seat. A portion of the inner circumferential wall of one rotating sleeve unit abuts against and is rotatably connected to the outer circumferential wall of one of the cross shafts. An inner sealing unit is sleeved on the outer circumferential side of one of the cross shafts. A side wall of the inner sealing unit, the inner circumferential wall of the rotating sleeve unit, and the outer circumferential wall of the cross shafts enclose and form a sealed rotating chamber. Two rotating sleeve units are respectively connected to both ends of a first fork unit. The remaining two rotating sleeve units are respectively connected to both ends of a second fork unit. Between the two rotating sleeve units connected to the first fork unit, there is one rotating sleeve unit connected to the second fork unit. An external sealing assembly includes a housing unit and four flexible sleeves. The housing unit is a hollow shell. Four clearance holes are provided around the circumference of the housing unit. The housing unit encloses and connects to the cross seat. One cross shaft passes through one clearance hole of the housing unit. One flexible sleeve is fitted around the outer periphery of a rotating sleeve unit. One end of the flexible sleeve is connected to the rotating sleeve unit, and the other end is connected to the housing unit. The four flexible sleeves, the housing unit, and the four rotating sleeve units surround and form a sealed protective chamber. Four inner sealing units are disposed within the protective chamber.

2. The multi-seal drive shaft according to claim 1, characterized in that, The outer casing unit includes two half-shells, four clearance holes, four second engagement slots, and four second retaining rings; the two half-shells are symmetrically spaced along the central plane; the two half-shells are at least partially circumferentially connected, forming four clearance holes spaced apart circumferentially along the half-shells; one second engagement slot is provided on the two half-shells; one second engagement slot is concentrically arranged with at least one clearance hole; one end of the soft sleeve is connected to the half-shells through the engagement of the second retaining rings and the second engagement slot.

3. The multi-seal drive shaft according to claim 2, characterized in that, The rotating sleeve unit includes a rotating sleeve body, a rolling element, a first engaging groove, and a first retaining spring; the rotating sleeve body is sleeved on the outer periphery of the cross shaft; the rolling element is disposed in the circumferential space between the rotating sleeve body and the cross shaft; the rolling element abuts against the inner peripheral wall of the rotating sleeve body and the outer peripheral wall of the cross shaft respectively; the first engaging groove is disposed on the outer peripheral wall of the rotating sleeve body; the end of the soft sleeve body away from the second engaging groove is connected to the rotating sleeve body through the engagement of the first retaining spring and the first engaging groove.

4. A multi-seal drive shaft according to claim 3, characterized in that, The outer casing unit also includes four extension sleeves; one end of each extension sleeve is connected to the half-shell, and the other end extends away from the half-shell; one of the extension sleeves is fitted onto the outer periphery of one of the soft sleeves.

5. A multi-seal drive shaft according to claim 4, characterized in that, The projection of the extension sleeve on the rotating body covers the first engagement groove.

6. A multi-seal drive shaft according to claim 4, characterized in that, The multi-sealed drive shaft also includes a filler; the outer shell unit also includes a filling nozzle; the filling nozzle is connected to the semi-shell; the multi-sealed drive shaft includes a filled state and a sealed state; the filled state includes the filling material being injected into the protective chamber through the filling nozzle; the sealed state includes the filling nozzle being closed, and the protective chamber being cut off from external space.

7. A multi-seal drive shaft according to claim 6, characterized in that, The rotating chamber is filled with the filler.

8. A multi-seal drive shaft according to claim 6, characterized in that, The filler in the protective chamber compresses the soft sleeve and expands towards the inner peripheral wall of the extension sleeve, causing a portion of the outer peripheral wall of the soft sleeve to abut against the inner peripheral wall of the extension sleeve.

9. A multi-seal drive shaft according to claim 1, characterized in that, The first fork unit includes a first fork seat, a first left fork arm, a first left fork hole, a first right fork arm, and a first right fork hole; one end of the first left fork arm is connected to the first fork seat, and the other end extends toward a first side of the first fork seat; One end of the first right fork arm is connected to the first fork seat, and the other end extends toward the first side of the first fork seat; the first left fork arm and the first right fork arm are spaced apart; the first left fork hole passes through the first left fork arm; the first right fork hole passes through the first right fork arm; the center line of the first left fork hole coincides with the center line of the first right fork hole; the two rotating sleeve units are respectively interference-fitted with the first left fork hole and the first right fork hole; The second fork unit includes a second fork seat, a second left fork arm, a second left fork hole, a second right fork arm, and a second right fork hole; one end of the second left fork arm is connected to the second fork seat, and the other end extends toward the second side of the second fork seat; one end of the second right fork arm is connected to the second fork seat, and the other end extends toward the second side of the second fork seat; the second left fork arm and the second right fork arm are spaced apart; the second left fork hole passes through the second left fork arm; the second right fork hole passes through the second right fork arm; the center line of the second left fork hole coincides with the center line of the second right fork hole; the two rotating sleeve units are respectively interference-fitted with the second left fork hole and the second right fork hole.

10. A multi-sealed drive shaft according to claim 1, characterized in that, The axle fork assembly further includes a first axle body and a second axle body; one end of the first axle body is connected to the first fork unit, and the other end extends away from the second fork unit; one end of the second axle body is connected to the second fork unit, and the other end extends away from the first fork unit.

Images