Heavy-load planetary lead screw assembly

Abstract

The utility model discloses a heavy load planet lead screw assembly which comprises a lead screw, a planet nut and a planet pin roller, the planet pin roller is arranged between the lead screw and the planet nut, cover plates are arranged at the two ends of the planet nut, the two ends of the planet pin roller are rotatably connected with the cover plates, and a threaded section is arranged at the position between the two ends of the planet pin roller. At least one end of the planetary nut is provided with a braking mechanism, the braking mechanism comprises an outer gear rotationally arranged at the end of the planetary nut, the outer gear is in transmission connection with the end of the planetary roller, the braking mechanism further comprises a braking assembly, and the braking assembly is used for limiting rotation of the outer gear relative to the planetary nut during power failure. By means of the built-in braking mechanism, when power is lost due to faults, the planetary nut is limited to move up and down relative to the lead screw by limiting rotation of the planetary pin roller, braking is stable and reliable, the electric cylinder is effectively protected, meanwhile, the electric cylinder is not affected by the using environment, the size is small, and the application range is wide.

Description

Technical Field

[0001] The utility model relates to the technical field of mechanical equipment accessories, in particular to a heavy-load planetary screw assembly. Background Art

[0002] The heavy-load planetary electric cylinder can basically meet the driving requirements when it is driven; however, when the heavy-load planetary electric cylinder is running under a high-load environment, the power is suddenly lost, and the screw of the planetary screw assembly will lose the driving force. At this time, the heavy object pushed / pulled will drive the screw to move rapidly in the opposite direction and impact the electric cylinder, causing damage to the internal parts of the electric cylinder;

[0003] However, in the prior art, the planetary screw assembly only serves to realize the conversion of linear motion through spiral motion. When the electric cylinder encounters the above-mentioned power failure, the planetary screw assembly itself does not have a braking function and needs to be completed by an external braking mechanism. However, the external braking mechanism has a large structure and is easily affected by the installation environment, resulting in a limited scope of application.

[0004] Therefore, it is necessary to develop a heavy-load planetary screw assembly. Through the built-in braking mechanism, in the event of a fault and power failure, the planetary nut can be limited to move up and down relative to the screw by limiting the rotation of the planetary roller. The braking is stable and reliable, which can effectively protect the electric cylinder while making the electric cylinder unaffected by the use environment. It is also small in size and has a wide range of applications. Utility Model Content

[0005] In order to solve the above problems, the technical solutions adopted by the utility model are as follows:

[0006] A heavy-load planetary screw assembly, comprising a screw, a planetary nut and a planetary roller, characterized in that the planetary roller is arranged between the screw and the planetary nut, a cover plate is arranged at both ends of the planetary nut, both ends of the planetary roller are rotatably connected to the cover plate, and a threaded section connected to the internal thread of the planetary nut and the screw thread is arranged at a position between the two ends of the planetary roller;

[0007] A braking mechanism is provided at at least one end of the planetary nut, and the braking mechanism includes an external gear rotatably provided at the end of the planetary nut, and the external gear is transmission-connected to the end of the planetary roller. The braking mechanism also includes a braking assembly, and the braking assembly is used to limit the rotation of the external gear relative to the planetary nut in the event of power failure.

[0008] Preferably, at least one end of the planetary roller is provided with a transmission gear, the transmission gear is located outside the cover plate, and the inner edge of the outer gear is provided with internal teeth meshing with the transmission gear.

[0009] Preferably, a bearing is provided between the external gear and the planetary nut.

[0010] Preferably, the external gear is a ratchet with external teeth on the outer edge, and the brake assembly includes a pawl and an electromagnet located on the outside of the external gear, the pawl is rotatably connected to the planetary nut through a connecting column, a torsion spring is provided between the pawl and the planetary nut, and the electromagnet is located on the side of the pawl away from the external gear. When the electromagnet is energized, the pawl moves away from the teeth of the external gear, and when the electromagnet is de-energized, the pawl engages with the teeth of the external gear.

[0011] Preferably, both ends of the planetary nut are provided with an external gear and a brake assembly, wherein one of the brake assemblies is used to prevent the external gear from rotating clockwise when the power is off, and the other brake assembly is used to prevent the external gear from rotating counterclockwise when the power is off.

[0012] Preferably, at least one end of the planetary nut is provided with a connecting boss, the connecting column is provided on the connecting boss, one end of the torsion spring is connected to the pawl, and the other end is connected to the connecting boss, and the electromagnet is connected to the connecting boss.

[0013] Preferably, the connecting boss, the connecting column and the planetary nut are integrally formed.

[0014] Preferably, a mounting boss connected to an external drive rod is provided on the outer side of the middle portion of the planetary nut.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] 1. The utility model has a built-in braking mechanism, which can limit the upward and downward movement of the planetary nut relative to the lead screw by limiting the rotation of the planetary roller in the event of a power failure. The braking is stable and reliable, which effectively protects the electric cylinder while preventing the electric cylinder from being affected by the use environment. It is also small in size and has a wide range of applications.

[0017] 2. By setting brake mechanisms at both ends of the planetary nut and applying them to the electric cylinder, it can simultaneously meet the application scenarios of pulling and pushing heavy objects. That is, when power is lost, the planetary nut can be prevented from moving upward and downward relative to the lead screw, which has a wider range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional structural schematic diagram of the utility model;

[0019] Figure 2 It is the front view of the utility model;

[0020] Figure 3 for Figure 2 Schematic diagram of the AA section structure;

[0021] Among them: screw 1, planetary nut 2, planetary roller 3, cover plate 4, external gear 5, brake assembly 6, transmission gear 7, torsion spring 8, connecting column 21, connecting boss 22, mounting boss 23, threaded section 31, internal teeth 51, external teeth 52, pawl 61, electromagnet 62. DETAILED DESCRIPTION

[0022] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively with reference to the accompanying drawings. The accompanying drawings provide preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0023] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may also be an element centered thereon. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an element centered thereon at the same time. The terms "vertical", "horizontal", "left", "right", "up", "down", "front", "rear" and similar expressions used herein are for illustrative purposes only.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0025] Below, in conjunction with the accompanying drawings and specific implementation methods, the utility model is further described:

[0026] like Figure 1-3 As shown, a heavy-load planetary screw assembly comprises a screw 1, a planetary nut 2 and a planetary roller 3, wherein the planetary roller 3 is arranged between the screw 1 and the planetary nut 2, and a cover plate 4 is arranged at both ends of the planetary nut 2, and both ends of the planetary roller 3 are rotatably connected to the cover plate 4, and a threaded section 31 threadedly connected to the internal thread of the planetary nut 2 and the screw 1 is arranged at a position between the two ends of the planetary roller 3;

[0027] At least one end of the planetary nut 2 is provided with a braking mechanism, which includes an external gear 5 rotatably arranged at the end of the planetary nut 2, and the external gear 5 is transmission-connected to the end of the planetary roller 3. The braking mechanism also includes a braking assembly 6, and the braking assembly 6 is used to limit the rotation of the external gear 5 relative to the planetary nut 2 in the event of power failure.

[0028] In this embodiment, since the outer gear 5 is in transmission connection with the end of the planetary roller 3, the outer gear 5 is prevented from rotating by the brake assembly 6 when power is lost. However, by limiting the rotation of the planetary roller 3, the planetary nut 2 is limited to move up and down relative to the screw rod 1. When applied to the electric cylinder, the driving rod connected to the planetary nut 2 can continue to move downward or upward at the moment of power loss.

[0029] The above structure has stable and reliable braking, effectively protects the electric cylinder and prevents the electric cylinder from being affected by the use environment, and has a small size and a wide range of applications.

[0030] Further, such as Figure 1 , 3 As shown, in order to realize the transmission connection between the external gear 5 and the planetary roller 3, a transmission gear 7 is provided at at least one end of the planetary roller 3, and the transmission gear 7 is located outside the cover plate 4. The inner edge of the external gear 5 is provided with internal teeth 51 meshing with the transmission gear 7.

[0031] Further, such as Figure 3 As shown, in order to make the external gear 5 connected to the planetary nut 2 only in a circumferential rotation, a bearing (not shown in the figure) is provided between the external gear 5 and the planetary nut 2.

[0032] Further, such as Figure 3 As shown, the external gear 5 is a ratchet with external teeth 52 on the outer edge, and the brake assembly 6 includes a pawl 61 and an electromagnet 62 located on the outside of the external gear 5, the pawl 61 is rotatably connected to the planetary nut 2 through a connecting column 21, a torsion spring 8 is provided between the pawl 61 and the planetary nut 2, and the electromagnet 62 is located on the side of the pawl 61 away from the external gear 5. When the electromagnet 62 is powered on, the pawl 61 is away from the external teeth 52 of the external gear 5, and when the electromagnet 62 is powered off, the pawl 61 is meshed with the external teeth 52 of the external gear 5.

[0033] In this embodiment, the external gear 5 is a ratchet with external teeth 52 on the outer edge, so that the external gear 5 and the pawl 61 form a ratchet mechanism. When the pawl 61 is changed from the energized state to the de-energized state by the setting of the torsion spring 8, the pawl 61 is automatically driven to engage with the external teeth 52 of the external gear 5 to prevent the external gear 5 from rotating. The electromagnet 62 is set so that the pawl 61 is kept away from the external teeth 52 of the external gear 5 in the energized state to ensure the normal rotation of the external gear 5.

[0034] In this embodiment, when returning to the normal state after braking, the electromagnet 62 is energized first, and then the screw rod 1 is rotated counterclockwise or clockwise for a certain angle, and then the screw rod 1 is rotated in the opposite direction, so that the pawl 61 can be reset to the energized state.

[0035] Further, such as Figure 1 ,2 As shown in 3, both ends of the planetary nut 2 are provided with an external gear 52 and a brake assembly 6, wherein one of the brake assemblies 6 is used to prevent the external gear 52 from rotating clockwise when the power is off, and the other brake assembly 6 is used to prevent the external gear 52 from rotating counterclockwise when the power is off.

[0036] In this embodiment, the above structure is applied to the electric cylinder, which can simultaneously meet the application scenarios of pulling and pushing heavy objects, that is, when power is lost, the planetary nut 2 can be prevented from moving upward and downward relative to the screw rod 1, and the scope of application is wider.

[0037] Further, such as Figure 1 , 2 As shown in Figure 3, in order to connect the pawl 61 and the electromagnet 62 to the planetary nut 2 and improve the connection stability and reliability, at least one end of the planetary nut 2 is provided with a connecting boss 22, the connecting column 21 is provided on the connecting boss 22, one end of the torsion spring 8 is connected to the pawl 61, and the other end is connected to the connecting boss 22, and the electromagnet 62 is connected to the connecting boss 22.

[0038] Further, such as Figure 3 As shown, in order to reduce the number of parts and installation procedures and improve connection reliability, the connecting boss 22, the connecting column 21 and the planetary nut 2 are integrally formed.

[0039] Further, such as Figure 3 As shown, a mounting boss 23 connected to an external driving rod is provided on the outer side of the middle portion of the planetary nut 2 .

[0040] For those skilled in the art, various other corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all of these changes and deformations should fall within the scope of protection of the claims of the utility model patent.

Claims

1. A heavy-load planetary screw assembly, comprising a screw, a planetary nut and a planetary roller, characterized in that: The planetary roller is arranged between the screw and the planetary nut, and cover plates are arranged at both ends of the planetary nut. Both ends of the planetary roller are rotatably connected to the cover plates, and a threaded section connected to the internal thread of the planetary nut and the screw thread is arranged between the two ends of the planetary roller. A braking mechanism is provided at at least one end of the planetary nut, and the braking mechanism includes an external gear rotatably provided at the end of the planetary nut, and the external gear is transmission-connected to the end of the planetary roller. The braking mechanism also includes a braking assembly, and the braking assembly is used to limit the rotation of the external gear relative to the planetary nut in the event of power failure.

2. A heavy-load planetary screw assembly according to claim 1, characterized in that: A transmission gear is disposed at at least one end of the planetary roller, the transmission gear is located outside the cover plate, and the inner edge of the outer gear is provided with internal teeth meshing with the transmission gear.

3. A heavy-load planetary screw assembly according to claim 1, characterized in that: A bearing is arranged between the external gear and the planetary nut.

4. A heavy-load planetary screw assembly according to claim 1, characterized in that: The external gear is a ratchet with external teeth on the outer edge. The brake assembly includes a pawl and an electromagnet located on the outside of the external gear. The pawl is rotatably connected to the planetary nut through a connecting column. A torsion spring is provided between the pawl and the planetary nut. The electromagnet is located on the side of the pawl away from the external gear. When the electromagnet is energized, the pawl is away from the teeth of the external gear. When the electromagnet is de-energized, the pawl meshes with the teeth of the external gear.

5. A heavy-load planetary screw assembly according to claim 1, characterized in that: Both ends of the planetary nut are provided with an external gear and a brake assembly, wherein one of the brake assemblies is used to prevent the external gear from rotating clockwise when the power is off, and the other brake assembly is used to prevent the external gear from rotating counterclockwise when the power is off.

6. A heavy-load planetary screw assembly according to claim 4, characterized in that: At least one end of the planetary nut is provided with a connecting boss, the connecting column is provided on the connecting boss, one end of the torsion spring is connected to the pawl, and the other end is connected to the connecting boss, and the electromagnet is connected to the connecting boss.

7. A heavy-load planetary screw assembly according to claim 6, characterized in that: The connecting boss, the connecting column and the planetary nut are integrally formed.

8. A heavy-load planetary screw assembly according to claim 6, characterized in that: A mounting boss connected to an external driving rod is arranged on the outer side of the middle part of the planetary nut.

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