Lead screw assembly bearing fixing structure of electric push rod

Abstract

The utility model discloses a lead screw assembly bearing fixing structure of an electric push rod. The lead screw assembly bearing fixing structure comprises a lead screw, a bearing, a plurality of sub-gaskets and a clamp spring. The bearing is arranged on the lead screw in a sleeving mode, and the multiple sub-gaskets are inserted into an annular groove in the periphery of the lead screw and spliced to form a closed annular gasket which is used for axially limiting an inner ring of the bearing. An annular step face is arranged on the lead screw and abuts against one side of the inner ring of the bearing, and bidirectional limiting of the bearing is achieved. The multiple sub-gaskets are spliced to form a clamp spring groove, and the clamp spring is clamped in the clamp spring groove and used for preventing the sub-gaskets from disengaging and further fixing the bearing. The structure is low in mounting space requirement, flexible to assemble, suitable for a compact or closed space, and good in stability and adaptability.

Description

Technical Field

[0001] This application relates to the field of electric linear actuator technology, specifically a bearing fixing structure for the lead screw assembly of an electric linear actuator. Background Technology

[0002] An electric linear actuator is a drive device that converts electrical energy into linear thrust. It primarily uses an electric motor to drive a lead screw to rotate, which in turn drives the actuator in a linear reciprocating motion. Electric linear actuators offer advantages such as compact structure, precise control, and sensitive response, and are widely used in various fields including medical equipment, smart homes, industrial automation, and agricultural machinery.

[0003] In the internal structure of an electric linear actuator, the lead screw assembly serves as the core transmission mechanism, and its operational stability and reliability directly affect the overall performance of the machine. To achieve smooth rotation of the lead screw, bearings are typically installed on it to support and guide the rotation. To prevent axial movement of the bearing due to external forces during rotation, reliable axial limiting and fixing of the bearing's inner ring is necessary.

[0004] In existing technologies, there are two main methods for axial positioning of bearings:

[0005] One method is to use a nut locking mechanism, which involves threading a nut onto the lead screw and screwing it in to abut against the inner ring of the bearing to achieve positioning. This method is simple in structure and easy to manufacture, but during long-term operation, the nut is prone to loosening due to external forces such as vibration and impact, which can lead to bearing displacement and affect the stability and service life of the electric actuator, especially under high load or frequent start-stop conditions.

[0006] The second method uses a riveting connection, where the limiting component is permanently fixed to the end of the lead screw by riveting, thereby achieving axial limiting of the bearing inner ring. Although this method results in a robust structure that is not easily loosened, it is a non-removable structure, making it difficult to repair or replace once assembled. If assembly errors occur or later maintenance is required, the entire lead screw assembly usually needs to be replaced, leading to high maintenance costs and significant resource waste.

[0007] To overcome the above shortcomings, patent document CN205846961U discloses an improved solution: a groove is provided on the outer peripheral wall of the lead screw, and a U-shaped limiting member is inserted therein. This limiting member, through its two arms, is inserted into the groove and cooperates with the inner ring of the bearing to form a limiting support. This structure avoids, to some extent, the disadvantages of nut loosening and non-removable riveting, and has a certain degree of ease of assembly and disassembly possibility. However, the above structure still has the following limitations:

[0008] 1. Limited assembly method: The limiting component is an integral structure, and its insertion requires a certain amount of space on the side of the lead screw. If there are housings, baffles or other components around the lead screw, the insertion operation will be restricted, the assembly flexibility is poor, and it is not conducive to on-site assembly and later maintenance.

[0009] 2. Uneven distribution of limiting force: The limiting component has an open U-shaped structure, which cannot form a truly closed ring support structure. The opening is prone to becoming a weak area when under stress. When the lead screw assembly is subjected to large axial tensile forces during operation, especially under conditions of repeated start-stop or high load of the electric actuator, the U-shaped limiting structure is prone to localized stress or stress concentration due to the structural discontinuity at the opening. This can lead to problems such as deformation, displacement, or even detachment of the limiting component, making it difficult to achieve stable and uniform bearing limiting. Utility Model Content

[0010] This application provides a bearing fixing structure for a lead screw assembly of an electric actuator, which achieves reliable axial positioning of the bearing by assembling multiple sub-washers into a closed annular washer.

[0011] The lead screw assembly bearing fixing structure of the electric linear actuator provided in this application includes:

[0012] Lead screw;

[0013] The bearing is sleeved on the lead screw;

[0014] Multiple sub-shiels are disposed on the lead screw and joined together to form a closed annular shield, the annular shield being used to restrict the bearing from moving axially along the lead screw.

[0015] Preferably, the outer peripheral wall of the lead screw is provided with an annular groove, and a plurality of sub-wafers are inserted into the annular groove.

[0016] Preferably, there are two sub-gaskets, both of which are semi-circular ring structures.

[0017] Preferably, the lead screw is provided with a positioning part for abutting one side of the bearing inner ring, and the annular washer is used to abut the other side of the bearing inner ring, thereby achieving bidirectional axial positioning of the bearing inner ring.

[0018] Preferably, the positioning part is an annular stepped surface provided on the outer peripheral wall of the lead screw.

[0019] Preferably, the lead screw is provided with a limiting member to prevent the sub-waist pad from disengaging from the lead screw.

[0020] Preferably, the limiting member is a retaining spring, and each of the sub-wafers is provided with a recess. Multiple recesses are combined to form a retaining spring groove on the outer periphery of the annular washer, and the retaining spring is engaged in the retaining spring groove.

[0021] Preferably, the retaining ring groove is an annular stepped groove provided on the outer periphery of the annular washer, and the two sides of the retaining ring abut against the inner ring of the bearing and the side wall of the retaining ring groove, respectively.

[0022] One or more technical solutions provided in this application have at least the following technical effects or advantages:

[0023] 1. The modular sub-shields can be inserted into the slots from multiple radial directions of the lead screw and assembled into a closed ring structure. Only the insertion space corresponding to the width of the shim needs to be reserved in each direction around the lead screw. The installation space requirements are lower and the assembly adaptability is stronger. It is especially suitable for applications with compact structure or limited space.

[0024] 2. Multiple sub-shims are assembled to form a closed annular shim, which can provide 360° annular support and limiting force for the bearing. This overcomes the stress concentration and off-center load problems caused by the non-closed structure of U-shaped or C-shaped opening limiting parts, ensuring a more stable and reliable limiting effect. Attached Figure Description

[0025] Figure 1 A schematic diagram of the bearing fixing structure of the lead screw assembly of the electric linear actuator provided in the embodiment of this application;

[0026] Figure 2 This is an exploded view of the bearing fixing structure of the lead screw assembly of the electric linear actuator provided in an embodiment of this application;

[0027] Figure 3 This is a cross-sectional view of the bearing fixing structure of the lead screw assembly of the electric linear actuator provided in the embodiment of this application;

[0028] Figure 4 A schematic diagram of the annular washer in the bearing fixing structure of the lead screw assembly of the electric linear actuator provided in this embodiment of the application;

[0029] Explanation of reference numerals in the attached drawings: 10, lead screw; 11, annular groove; 12, annular stepped surface; 20, bearing; 30, annular washer; 31, sub-waist washer; 311, recess; 32, snap ring groove; 40, snap ring. Detailed Implementation

[0030] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0031] The bearing fixing structure of the lead screw assembly of the electric linear actuator in this embodiment is suitable for electric linear actuator devices with a rotating lead screw transmission structure. It aims to achieve stable axial limiting and fixing of the bearing 20 on the lead screw 10, and has good ease of disassembly and assembly and structural adaptability.

[0032] like Figures 1-3 As shown, this embodiment provides a lead screw assembly bearing fixing structure for an electric actuator, including a lead screw 10, a bearing 20, multiple sub-washers 31, and a retaining ring 40.

[0033] The lead screw 10 is a helical transmission rod with one end connected to a motor and the other end connected to a thrust structure. Its outer peripheral wall is provided with an annular groove 11 and an annular stepped surface 12. The annular groove 11 is used to install and limit the sub-shield 31, and the annular stepped surface 12 is provided on one side of the inner ring of the bearing 20 to form a first axial limiting surface for the inner ring of the bearing 20.

[0034] The bearing 20 is sleeved on the lead screw 10, with its inner ring interference-fitted to the lead screw 10 to support the rotation of the lead screw 10, and its outer ring installed inside the push rod body housing. To prevent the bearing 20 from moving axially, this embodiment implements bidirectional axial limiting on its inner ring.

[0035] Specifically, multiple combinable sub-wafers 31 are provided on the other side of the inner ring of the bearing 20. These sub-wafers 31 are installed in the annular groove 11 of the lead screw 10, and after assembly, form a complete closed annular washer 30. Preferably, there are two sub-wafers 31, which are semi-circular rings. They are inserted into the groove 11 from both sides of the lead screw 10, and radially mated together. After being assembled into a complete closed ring, they abut against the inner ring of the bearing 20, forming a second axial limiting surface, thereby achieving bidirectional axial limiting of the inner ring of the bearing 20.

[0036] Compared to the existing technology that uses an integrated limiting gasket that needs to be installed from one side of the lead screw and requires a large amount of axial space for the lead screw, the modular structure used in this embodiment only requires reserving a space of the size of a sub-gasket 31 on both sides of the lead screw 10 for individual insertion, which significantly reduces the assembly space requirement and improves the assembly flexibility and adaptability in compact or enclosed structural environments.

[0037] To prevent the assembled annular washer 30 from falling off during screw rotation or vibration, this embodiment further includes a limiting component for reliable positioning. Preferably, the limiting component is a retaining spring 40. Figure 4As shown, each sub-waist 31 has a semi-circular recess 311 on its outer side. After the sub-waists 31 are assembled, the multiple recesses 311 together form a retaining ring groove 32 on the outer periphery of the annular washer 30. The retaining ring 40 is elastically engaged in the retaining ring groove 32. The retaining ring groove 32 is preferably an annular stepped groove. After the retaining ring 40 is assembled, its two sides abut against the inner ring of the bearing 20 and the side wall of the retaining ring groove 32, respectively, thereby achieving further axial positioning of the inner ring of the bearing 20.

[0038] In other embodiments, the number of sub-shiels 31 can be adjusted according to actual needs. For example, three 120° structures, four 90° structures or more equally divided structures can be used. The splicing structure can also be a straight-cut face-to-face joint, a stepped splicing, or a structure with positioning tenons and grooves to improve splicing stability and concentricity.

[0039] In addition, the limiting component can be replaced with other elastic or mechanical limiting structures, such as elastic positioning pins, spring clip fasteners, and rotary locking structures, to provide more limiting forms. To further improve the anti-rotation performance of the annular gasket 30, anti-rotation structures, such as limiting protrusions, positioning slots, and rotary buckles, can be set at the end or periphery of the sub-gasket 31 to enhance the stability and reliability during operation from a structural perspective.

[0040] In summary, the bearing fixing structure of the electric linear actuator screw assembly provided in this embodiment has a reasonable structural design and advantages such as convenient assembly, strong spatial adaptability, and high limiting stability. It is suitable for electric linear actuator devices in various complex or compact space scenarios and has good practicality and promotion value.

[0041] This specification and accompanying drawings are merely illustrative examples of this application and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from its scope. Therefore, if such modifications and modifications fall within the scope of this application and its equivalents, this application intends to include such modifications and modifications.

Claims

1. A bearing fixing structure of a screw assembly of an electric push rod, characterized by, The utility model relates to a bearing limiting device for a screw rod, comprising: a screw rod (10); a bearing (20) sleeved on the screw rod (10); a plurality of sub-gaskets (31) arranged on the screw rod (10) and spliced to form a closed annular gasket (30) for limiting axial movement of the bearing (20) along the screw rod (10).

2. The bearing fixing structure of the electric push rod's screw assembly shaft according to claim 1, wherein, The outer circumferential wall of the screw rod (10) is provided with an annular groove (11), and the plurality of sub-gaskets (31) are inserted into the annular groove (11).

3. The bearing fixing structure of the electric push rod's screw assembly shaft according to claim 1, wherein, The sub-gaskets (31) are two, both of which are semicircular annular structures.

4. The bearing fixing structure of the electric push rod's screw assembly shaft according to claim 1, wherein, The screw rod (10) is provided with a positioning portion for abutting one side of the inner ring of the bearing (20), and the annular gasket (30) is used for abutting the other side of the inner ring of the bearing (20), so as to realize bidirectional axial positioning of the inner ring of the bearing (20).

5. The bearing fixing structure of the electric push rod's screw assembly shaft according to claim 4, wherein, The positioning portion is an annular stepped surface (12) provided on the outer circumferential wall of the screw rod (10).

6. The bearing fixing structure for a lead screw assembly of an electric push rod according to any one of claims 1 to 5, wherein The screw rod (10) is provided with a limiting piece for preventing the sub-gaskets (31) from being separated from the screw rod (10).

7. The bearing fixing structure of the electric push rod's screw assembly shaft according to claim 6, wherein, The limiting piece is a clasp spring (40), each sub-gasket (31) is provided with a recess (311), and a plurality of recesses (311) are combined to form a clasp spring groove (32) provided on the outer circumferential portion of the annular gasket (30), and the clasp spring (40) is clamped in the clasp spring groove (32).

8. The bearing fixing structure of the electric push rod's screw assembly shaft according to claim 7, wherein, The clasp spring groove (32) is an annular stepped groove provided on the outer circumferential portion of the annular gasket (30), and the two sides of the clasp spring (40) abut against the inner ring of the bearing (20) and the side wall of the clasp spring groove (32), respectively.

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