Electric cylinder support mechanism and electric cylinder

Abstract

The application relates to an anti-impact supporting mechanism, in particular to an electric cylinder supporting mechanism and electric cylinder, which comprises an inner ring, an outer ring, a rolling pin and retainer assembly, a first thrust cylindrical roller assembly, a second thrust cylindrical roller assembly, a first thrust bearing retainer, a second thrust bearing retainer, a bearing sleeve and an end sleeve. The outer ring is arranged outside the inner ring, the rolling pin and retainer assembly are arranged between the inner ring and the outer ring, the first thrust cylindrical roller assembly and the second thrust cylindrical roller assembly are sleeved on the inner ring, the bearing sleeve is sleeved on the outer ring, one part of the end sleeve is connected to the inner wall of the bearing sleeve, and the other part of the end sleeve extends out of the bearing sleeve. The application can bear radial force and bidirectional axial force, and can meet the special requirements of the transmission shaft and the lead screw when being separated and combined.

Description

Technical Field

[0001] This invention relates to an impact-resistant support mechanism, specifically to an electric cylinder support mechanism and an electric cylinder. Background Technology

[0002] Electric cylinders are being used more and more widely at present, and the use of anti-reverse mechanism in electric cylinders is becoming more and more important. Although the traditional sliding guide structure is simple in structure, it suffers from severe wear during operation and is not suitable for long-term use.

[0003] In the field of electric drive technology, to ensure the installation of the nut, the lead screw must have an open thread structure at one end. Adding support structures at both ends of the lead screw can improve the rigidity of the transmission system and effectively avoid vibration caused by insufficient rigidity during the operation of long-stroke lead screws. The following requirements apply to different installation methods during the design of the lead screw's root diameter.

[0004] When the lead screw assembly is installed with one end fixed and the other end free or movable:

[0005]

[0006] When the lead screw assembly is installed with both ends fixed:

[0007]

[0008] F0 — Force on the leadscrew (N)

[0009] L—Maximum distance from the nut to the support at the fixed end of the lead screw (mm)

[0010] δ m —Estimated maximum permissible axial deformation of the leadscrew (μm)

[0011] As can be seen from the above formula, to achieve the same support stiffness, the bottom diameter of the lead screw can be reduced by half when both ends are fixed. However, electric cylinders have stricter requirements on diameter, therefore, support mechanisms must be installed at both ends of the lead screw.

[0012] However, with the advent of multi-stage electric cylinders, existing support mechanisms cannot meet the usage requirements of multi-stage electric cylinders. During the extension process of a multi-stage electric cylinder, the first-stage lead screw disengages from the next-stage lead screw, and re-engages during retraction. The electric cylinder support mechanism must not only withstand radial forces, but also axial impact forces that occur during engagement. Existing support mechanisms cannot meet these requirements. Summary of the Invention

[0013] The problem solved by this invention is to provide an electric cylinder support mechanism that can withstand both radial force and axial force in both directions, and can meet the special requirements of the transmission shaft and the lead screw when disengaging and engaging.

[0014] To address the aforementioned problems, this invention provides an electric cylinder support mechanism, comprising an inner ring, an outer ring, a needle roller and cage assembly, a first thrust cylindrical roller assembly, a second thrust cylindrical roller assembly, a first thrust bearing retaining ring, a second thrust bearing retaining ring, a bearing sleeve, and an end sleeve. The outer ring is disposed outside the inner ring, and the needle roller and cage assembly is disposed between the inner and outer rings. The first and second thrust cylindrical roller assemblies are fitted onto the inner ring, and are respectively located on opposite sides of the needle roller and cage assembly. The first thrust bearing retaining ring is connected to one end of the inner ring and disposed near the first thrust cylindrical roller assembly, and the second thrust bearing retaining ring is connected to the other end of the inner ring and disposed near the second thrust cylindrical roller assembly. The bearing sleeve is fitted onto the outer ring, and a portion of the end sleeve is connected to the inner wall of the bearing sleeve, while the other portion of the end sleeve extends beyond the bearing sleeve. The bearing sleeve, the end sleeve, and the outer ring move synchronously.

[0015] Furthermore, a radial boss is provided on the inner wall of one end of the bearing sleeve, and the end of the end sleeve located on the inner wall of the bearing sleeve abuts against one end of the outer ring, with the boss and the end sleeve clamping the outer ring therein.

[0016] Furthermore, the end sleeve is threadedly connected to the bearing sleeve.

[0017] Furthermore, the end sleeve is made of copper.

[0018] Furthermore, it also includes a guide strip, which is disposed on the outer wall of the bearing sleeve, the guide strip is disposed along the circumference of the bearing sleeve, and the guide strip protrudes from the surface of the bearing sleeve.

[0019] Furthermore, the guide belt is made of a wear-resistant material.

[0020] The present invention provides an electric cylinder, including the electric cylinder support mechanism described above.

[0021] Furthermore, the electric cylinder also includes a primary lead screw and a secondary four-bar screw, with an anti-collision component provided at the end of the primary lead screw.

[0022] This invention discloses an electric cylinder support mechanism. The presence of a first thrust cylindrical roller assembly and a second thrust cylindrical roller assembly outside the inner ring significantly enhances the axial load-bearing capacity and improves the impact resistance of the support mechanism. Simultaneously, the arrangement of needle rollers and a cage assembly between the inner and outer rings increases the axial contact area within a limited radial dimension, improving radial load-bearing capacity while ensuring the stability of the support structure. Furthermore, the overall structure is easy to install, has a small radial dimension, and is suitable for lead screw support structures with impact load requirements. It has shown good performance in a multi-stage electric cylinder. After 3000 reliability tests, the electric cylinder support mechanism of this invention exhibited excellent performance, with no damage to any parts. Attached Figure Description

[0023] Figure 1 This is a structural diagram of the electric cylinder support mechanism of the present invention;

[0024] Figure 2 This is a diagram showing the application of the electric cylinder support mechanism of the present invention in a multi-stage electric cylinder;

[0025] Figure 3 This is a schematic diagram showing the connection relationship between the electric cylinder support mechanism and the transmission shaft of the present invention. Detailed Implementation

[0026] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0027] In the embodiments of the present invention, the terms “up,” “down,” “front,” “back,” “left,” and “right,” etc., indicate directions or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are used only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0028] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "set", "install", "connect", and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0029] If the embodiments of the present invention involve descriptions such as "first" or "second", such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated.

[0030] like Figure 1 , Figure 2 As shown, the present invention provides an electric cylinder support mechanism, comprising an inner ring 11, an outer ring 12, a needle roller and cage assembly 13, a first thrust cylindrical roller assembly 14, a second thrust cylindrical roller assembly 15, a first thrust bearing retaining ring 16, a second thrust bearing retaining ring 17, a bearing sleeve 18, and an end sleeve 181. The outer ring 12 is disposed outside the inner ring 11, and the needle roller and cage assembly 13 is disposed between the inner ring 11 and the outer ring 12. The first thrust cylindrical roller assembly 14 and the second thrust cylindrical roller assembly 15 are sleeved on the inner ring 11, and the first thrust cylindrical roller assembly... 14. The second thrust cylindrical roller assembly 15 is located on both sides of the needle roller and cage assembly 13. The first thrust bearing retaining ring 16 is disposed at one end of the inner ring 11 and close to the first thrust cylindrical roller assembly 14. The second thrust bearing retaining ring 17 is disposed at the other end of the inner ring 11 and close to the second thrust cylindrical roller assembly 15. The bearing sleeve 18 is sleeved on the outer ring 12. The end sleeve 181 is partially connected to the inner wall of the bearing sleeve 18, and the other part of the end sleeve 181 extends out of the bearing sleeve 18. The bearing sleeve 18, the end sleeve 181, and the outer ring 12 move synchronously. Figure 3As shown, the electric cylinder support mechanism 10 of the present invention is connected to the end of the transmission shaft 22. Specifically, the electric cylinder support mechanism 10 of the present invention is connected to the transmission shaft 22 via a mounting plate 31. The mounting plate 31 is provided with a connecting hole and abuts against the first thrust bearing retaining ring 16. The connecting bolt passes through the connecting hole on the mounting plate 31 to connect the electric cylinder support mechanism 10 of the present invention to the transmission shaft 10, pressing the second thrust bearing retaining ring 17 between the transmission shaft 22 and the inner ring 11. The transmission shaft 22 drives the electric cylinder support mechanism 11 of the present invention. Firstly, it is connected to the first-stage lead screw 23. The electric cylinder support mechanism 11 of the present invention is located in the inner cavity of the first-stage lead screw 23. The transmission shaft 22 drives the first thrust bearing retaining ring 16, the second thrust bearing retaining ring 17, the inner ring 11 to rotate synchronously with the transmission shaft 22. The bearing sleeve 18, the end sleeve 181, and the guide belt 19 drive the first-stage lead screw 23 to move axially. The radial force generated by the first-stage lead screw 23 is transmitted to the bearing sleeve 18 through the guide belt 19. The bearing sleeve 18 and the inner ring 11 transmit radial load and ensure relative rotational movement through the needle roller and cage assembly 13. When the primary lead screw 23 rotates relative to the secondary lead screw 24, the needle roller and cage assembly 13 provides radial support, improving the rigidity of the primary lead screw 23. As the electric cylinder extends, after the primary lead screw 23 separates from the secondary lead screw 24, the electric cylinder support mechanism of the present invention rotates as a whole with the primary lead screw 23. When the primary lead screw 23 is engaged with the electric cylinder support mechanism of the present invention, the anti-collision component 25 collides with the end sleeve 181, and the impact force is transmitted through the end sleeve 181 to the outer ring 12 and then to the first thrust cylindrical roller assembly 14 and the second thrust cylindrical roller assembly 15. While ensuring that the primary lead screw 23 rotates relative to the secondary lead screw 24, the first thrust cylindrical roller assembly 14 and the second thrust cylindrical roller assembly 15 transmit the impact force to the first thrust bearing retainer ring 16 and the second thrust bearing retainer ring 17 and then to the primary lead screw 23. Meanwhile, the axial force generated by friction during the movement of the first-stage lead screw 23 can be borne by the first thrust cylindrical roller assembly 14 and the second thrust cylindrical roller assembly 15.

[0031] This invention discloses an electric cylinder support mechanism. Because the inner ring 11 is equipped with a first thrust cylindrical roller assembly 14 and a second thrust cylindrical roller assembly 15, the axial load-bearing capacity of the electric cylinder support mechanism is greatly enhanced, improving its impact resistance. Simultaneously, the needle roller and cage assembly 13 between the inner ring 11 and the outer ring 12 increases the axial contact area within a limited radial dimension, improving radial load-bearing capacity while ensuring the stability of the support structure. Furthermore, the overall structure is easy to install, has a small radial dimension, and is suitable for screw support structures with impact load requirements. It has shown good performance in a multi-stage electric cylinder. After 3000 reliability tests, the electric cylinder support mechanism of this invention performed well, and all parts showed no damage.

[0032] Optionally, a radial boss 182 is provided on the inner wall of one end of the bearing sleeve 18, and the end sleeve 181 located on the inner wall of the bearing sleeve 18 abuts against one end of the outer ring 12, with the boss 182 and the end sleeve 181 clamping the outer ring 12 therein.

[0033] Optionally, the end sleeve 181 is threaded onto the bearing sleeve 18.

[0034] Optionally, the end sleeve 181 is made of copper.

[0035] Optionally, it also includes a guide belt 19, which is disposed on the outer wall of the bearing sleeve 18, and the guide belt 19 is arranged circumferentially along the bearing sleeve 18 and protrudes out of the bearing sleeve 18. Specifically, the guide belt 19 is made of polytetrafluoroethylene (PTFE) or other wear-resistant materials, and the guide belt 19 serves a supporting function.

[0036] The present invention provides an electric cylinder, including the electric cylinder support mechanism 10 described above.

[0037] Optionally, the electric cylinder includes a primary lead screw 23 and a secondary four-bar screw 24, and the end of the primary lead screw 23 is provided with an anti-collision component 25.

[0038] While the disclosure is as stated above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of this disclosure, and all such changes and modifications will fall within the protection scope of this invention.

Claims

1. An electric cylinder support mechanism, characterized in that, The bearing assembly includes an inner ring (11), an outer ring (12), a needle roller and cage assembly (13), a first thrust cylindrical roller assembly (14), a second thrust cylindrical roller assembly (15), a first thrust bearing retainer ring (16), a second thrust bearing retainer ring (17), a bearing sleeve (18), an end sleeve (181), and a guide belt (19). The outer ring (12) is disposed outside the inner ring (11), and the needle roller and cage assembly (13) is disposed between the inner ring (11) and the outer ring (12). The first thrust cylindrical roller assembly (14) and the second thrust cylindrical roller assembly (15) are fitted onto the inner ring (11), and the first thrust cylindrical roller... The sub-assembly (14) and the second thrust cylindrical roller assembly (15) are respectively located on both sides of the needle roller and cage assembly (13). The first thrust bearing retainer ring (16) is disposed at one end of the inner ring (11) and close to the first thrust cylindrical roller assembly (14). The second thrust bearing retainer ring (17) is disposed at the other end of the inner ring (11) and close to the second thrust cylindrical roller assembly (15). The bearing sleeve (18) is sleeved on the outer ring (12). The end sleeve (181) is partially connected to the inner wall of the bearing sleeve (18), and the other part of the end sleeve (181) extends out of the bearing sleeve (18). The bearing sleeve (18), the end sleeve (181), and the outer ring (12) move synchronously. A radial boss (182) is provided on the inner wall of one end of the bearing sleeve (18). The end of the end sleeve (181) located on the inner wall of the bearing sleeve (18) abuts against one end of the outer ring (12). The boss (182) and the end sleeve (181) clamp the outer ring (12) therein. The guide band (19) is provided on the outer wall of the bearing sleeve (18). The guide band (19) is provided along the circumference of the bearing sleeve (18). The guide band (19) protrudes from the surface of the bearing sleeve (18).

2. The electric cylinder support mechanism according to claim 1, characterized in that, The end sleeve (181) is threaded onto the bearing sleeve (18).

3. The electric cylinder support mechanism according to claim 2, characterized in that, The end sleeve (181) is made of copper.

4. The electric cylinder support mechanism according to claim 3, characterized in that, The guide belt (19) is made of wear-resistant material.

5. An electric cylinder, characterized in that, Includes the electric cylinder support mechanism described in any one of claims 1-4.

6. An electric cylinder according to claim 5, characterized in that, The electric cylinder also includes a primary lead screw (23) and a secondary four-bar screw (24), and the end of the primary lead screw (23) is provided with an anti-collision component (25).

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