A planetary roller screw pair with self-protection from jamming and use method thereof

Abstract

The present invention provides a planetary roller screw pair with self-protection from jamming and a method of use, belonging to the technical field of planetary roller screws. The present invention solves the problem of irreversible damage such as breakage of the screw after jamming by designing that the power output end of the redundant module and the input module are detachably connected to the screw. The device includes a screw, a roller, a first sleeve, a load ring, a redundant module and an input module, the rollers are radially arranged around the screw and are closed by the first sleeve, the screw passes through the first sleeve and meshes with the rollers, and the rollers are rotatably connected to the first sleeve; the redundant module connects the inner wall of the load ring and the outer wall of the first sleeve in the manner of a ball screw pair, the input module and the screw are detachably connected, and the rotation of the first sleeve around the axis of the screw drives the input module to detach from the screw.

Description

Technical Field

[0001] The invention belongs to the technical field of planetary roller screws, and in particular relates to a planetary roller screw pair with self-protection from jamming and a use method thereof. Background Art

[0002] The planetary roller screw pair is a transmission device that converts rotational motion into linear motion. It has the advantages of high load-bearing capacity, high precision, fast frequency response and low noise when running at high speed. It is widely used in CNC machine tools, aerospace and other fields.

[0003] In the prior art, the three main components of a planetary roller screw pair are a screw, a nut and rollers, and usually also include components such as a load flange. The rollers are radially arranged around the screw and enclosed by the nut. The screw passes through the nut and meshes with the rollers inside the nut. The load flange is sleeved on the outer wall of the nut. The specific working process is: the power device drives the screw to rotate, and the rotation of the screw drives the rollers to rotate around the screw (similar to the planetary gear to the sun gear, which has both rotation and revolution), and then drives the nut to move along the axial direction of rotation, and finally drives the load flange to translate.

[0004] After the planetary roller screw pair has been working for a period of time, due to the influence of dust and the accuracy of component processing and assembly, jamming may occur between the screw and the roller. Once jamming occurs, the rotation of the roller around the screw will stop. Instead, the roller will rotate with the screw but will not rotate itself, and will rotate with the nut and load flange along with the screw without translation. The force generated by the object carried by the load flange will be converted into a torque in the opposite direction of rotation. At this time, the rotation of the screw will be subject to a large resistance torque, resulting in irreversible damage such as breakage. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a planetary roller screw pair with self-protection from jamming, so as to solve the problem in the prior art that the screw is prone to irreversible damage such as breakage after jamming of the screw and the roller.

[0006] In order to achieve the above-mentioned object and other related objects, the present invention provides a planetary roller screw pair with self-protection from jamming, comprising:

[0007] A lead screw, a roller and a first sleeve, wherein the rollers are radially arranged around the lead screw and are enclosed by the first sleeve, the lead screw passes through the first sleeve and meshes with the rollers, the rollers and the first sleeve are rotatably connected, the rollers and the first sleeve are relatively limited in the axial direction of the lead screw, the lead screw and the first sleeve are coaxial, and the central axis of the rollers and the central axis of the lead screw are parallel to each other;

[0008] A load ring and a redundant module, wherein the redundant module connects the inner wall of the load ring and the outer wall of the first sleeve in a ball screw pair;

[0009] An input module, wherein the input module and the lead screw are detachably connected;

[0010] Rotation of the first sleeve about the lead screw axis drives the input module to disengage from the lead screw.

[0011] Optionally, the input module includes an input shaft, a spline connection component and a locking component, the screw and the input shaft are relatively limited in radial and circumferential directions by the spline connection component, and the locking component is used to lock or disconnect the axial connection between the screw and the spline connection component.

[0012] Optionally, the locking component includes:

[0013] A hollow telescopic rod, one end of which is fixedly connected to the first sleeve, the other end of which is provided with a drop-out groove, the lead screw passes through the hollow telescopic rod and is connected to the spline connection component;

[0014] A fixing ring, the fixing ring being installed between the hollow telescopic rod and the spline connection component, the fixing ring being fixedly connected to the external working platform, and the lead screw passing through the fixing ring;

[0015] A hook, wherein the hook is mounted on the fixing ring, one end of the hook and the inner wall of the hollow telescopic rod are relatively limited in the axial and radial directions, and the other end of the hook and the spline connection component are relatively limited in the axial and radial directions. When the lead screw is stuck, the hook rotates relative to the hollow telescopic rod and is unlocked from the hollow telescopic rod through the drop-out groove.

[0016] Optionally, the spline connecting component includes an internal spline hollow shaft and a spline connecting shaft, one end of the internal spline hollow shaft is fixedly connected to the input shaft, the other end of the internal spline hollow shaft and one end of the spline connecting shaft are relatively limited in radial and circumferential directions by a spline structure, and the other end of the spline connecting shaft and the lead screw are relatively limited in radial and circumferential directions by a spline structure.

[0017] Optionally, it further comprises: a tension spring, one end of which is fixedly connected to the spline connecting shaft, and the other end of which is fixedly connected to the internal spline hollow shaft, and the axial movement distance of the spline connecting shaft pulled by the tension spring is greater than the axial connection length between the spline connecting shaft and the lead screw. Optionally, a buffer spring is arranged between the spline connecting shaft and the internal spline hollow shaft.

[0018] Optionally, a snap-fit ​​component is provided at one end of the spline connecting shaft, and when jamming occurs, the lead screw and the spline connecting shaft are disconnected, and the spline connecting shaft and the internal spline hollow shaft are axially limited to each other by the snap-fit ​​component.

[0019] Optionally, a slide groove is provided on the inner wall of the internal spline hollow shaft, and a groove is provided at the end of the slide groove, and the groove passes through the internal spline hollow shaft;

[0020] The buckle component includes a buckle, a buckle spring and a telescopic slot, the buckle spring is fixedly installed in the telescopic slot, the rebound and contraction directions of the buckle spring are along the radial direction of the lead screw, one end of the buckle is fixedly connected to the buckle spring and is located in the telescopic slot, and the other end of the buckle is located outside the telescopic slot, and after the buckle slides along the slide slot into the groove, the spline connecting shaft and the inner spline hollow shaft are locked.

[0021] Optionally, the redundant module includes a second sleeve, a raceway and a ball, the inner wall of the second sleeve wraps around the outer wall of the first sleeve, the first sleeve and the second sleeve are fixedly connected together, the first sleeve and the second sleeve are detachable, the raceway is continuously arranged on the outer wall of the second sleeve in an axial direction in a spiral shape, the ball is located between the second sleeve and the load ring, and the first sleeve drives the ball to roll along the raceway when rotating around the axis of the screw, and the second sleeve and the screw are coaxial.

[0022] A method for using a planetary roller screw pair with self-protection from jamming described above includes the following steps:

[0023] Normal movement of the lead screw pair: the input module drives the lead screw to rotate, and the rotational movement of the lead screw is converted into the translational movement of the load ring through the lead screw pair;

[0024] Troubleshooting after jamming occurs: the roller stops rotating around the lead screw, and instead rotates with the lead screw but does not rotate on its own, and rotates with the first sleeve, and finally drives the input module to detach from the lead screw, the rotation of the lead screw stops, the load ring is removed, and the jammed parts are sent for repair;

[0025] Restoring motion: Install the replaced parts, connect the input module and the lead screw together, and the input module drives the lead screw to rotate again, and converts it into translational motion of the load ring.

[0026] As described above, the planetary roller screw pair with self-protection from jamming of the present invention has at least the following beneficial effects:

[0027] 1. The present application uses the redundant module to connect the inner wall of the load ring and the outer wall of the first sleeve in the form of a ball screw pair, and the rotation of the first sleeve around the axis of the screw drives the input module to disengage from the screw. When the screw and the roller are stuck, due to the connection between the load ring and the first sleeve, the load ring will not generate excessive resistance torque on the screw. At the same time, after the sticking occurs, the first sleeve will rotate around the axis of the screw to drive the input module to disengage from the screw in time, avoiding the continuous rotation of the screw after the sticking to generate excessive torque, and finally solving the problem of irreversible damage such as screw breakage caused by the sticking of the planetary roller screw pair in the technical background.

[0028] 2. In the present application, through the design of the hollow telescopic rod, when the planetary roller screw pair with self-protection from getting stuck works normally, the hollow telescopic rod stretches and retracts with the translation of the load ring, and the hollow telescopic rod plays a role similar to that of a track; when the planetary roller screw pair with self-protection from getting stuck gets stuck, the hollow telescopic rod plays the role of a connecting piece, and through the connection of the telescopic rod to the second sleeve and the hook on the fixed ring, the rotation of the second sleeve drives the spline connecting shaft and the screw to disengage from each other.

[0029] 3. In the present application, through the design of the snap-fit ​​component, when jamming occurs, after the spline connecting shaft and the lead screw are disconnected, the snap-fit ​​can be stuck in the groove, thereby avoiding the rebound of the tension spring, which causes the spline connecting shaft and the lead screw to be connected again when the jamming fault has not been eliminated. After the jamming fault is eliminated, it is necessary to press the snap-fit ​​and then pull the spline connecting shaft to connect the spline connecting shaft and the lead screw together again.

[0030] As described above, the method for using a planetary roller screw pair with self-protection from jamming of the present invention has at least the following beneficial effects:

[0031] 1. The present application is designed with steps for troubleshooting and restoring motion after a jam occurs. After the input module and the screw are separated, the load ring can be quickly and smoothly removed and replaced with new parts, thereby restoring the normal motion of the planetary roller screw pair. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Shown is a schematic diagram of a planetary roller screw pair with self-protection from sticking according to the present invention.

[0033] Figure 2 Shown is a schematic exploded view of the interior of the load ring of the present invention.

[0034] Figure 3Shown is a schematic structural diagram of the hollow telescopic rod of the present invention.

[0035] Figure 4 Shown is a schematic diagram of the locking component of the present invention.

[0036] Figure 5 Shown is a schematic diagram of the buckle component of the present invention.

[0037] Component number description

[0038] Screw 11, roller 12, first sleeve 13, load ring 14, retaining frame 15, inner ring gear 16, outer ring gear 17, redundant module 2, second sleeve 21, raceway 22, ball 23, input module 3, input shaft 31, spline connection component 32, inner spline hollow shaft 321, spline connection shaft 322, annular groove 3221, locking component 33, hollow telescopic rod 331, first hollow sleeve 3311, second hollow sleeve 3312, third hollow sleeve 3313, falling groove 332, fixing ring 333, hook 334, protrusion 3341, tensioning spring 335, buffer spring 336, snap component 34, slide groove 341, groove 342, snap 343, snap spring 344, telescopic groove 345. DETAILED DESCRIPTION

[0039] The following is a description of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0040] See also Figures 1 to 5 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0041] The following embodiments are only for illustration purposes and can be combined with each other, and are not limited to the contents presented in the following single embodiments.

[0042] See also Figure 1 to Figure 2 The present invention provides a planetary roller screw pair with self-protection from jamming, comprising:

[0043] A lead screw 11, a roller 12 and a first sleeve 13, wherein the roller 12 is radially arranged around the lead screw 11 and is enclosed by the first sleeve 13, the lead screw 11 passes through the first sleeve 13 and meshes with the roller 12, the roller 12 and the first sleeve 13 are rotatably connected, the roller 12 and the first sleeve 13 are relatively limited in the axial direction of the lead screw 11, the lead screw 11 and the first sleeve 13 are coaxial, and the central axis of the roller 12 and the central axis of the lead screw 11 are parallel to each other;

[0044] A load ring 14 and a redundant module 2, wherein the redundant module 2 connects the inner wall of the load ring 14 and the outer wall of the first sleeve 13 in a ball screw pair;

[0045] An input module 3, wherein the input module 3 and the lead screw 11 are detachably connected, and the rotation of the first sleeve 13 around the axis of the lead screw 11 drives the input module 3 to detach from the lead screw 11;

[0046] We use the redundant module 2 to connect the inner wall of the load ring 14 and the outer wall of the first sleeve 13 in the form of a ball screw pair, and the rotation of the first sleeve 13 around the axis of the screw 11 drives the input module 3 to disengage from the screw 11. When the screw 11 and the roller 12 are stuck, due to the connection between the load ring 14 and the first sleeve 13, the load ring 14 will not generate excessive resistance torque on the screw 11. At the same time, after the sticking occurs, the first sleeve 13 will rotate around the axis of the screw 11 to drive the input module 3 to disengage from the screw 11 in time, avoiding the continuous rotation of the screw 11 after the sticking to generate excessive torque, and finally solving the problem of irreversible damage such as screw breakage caused by the sticking of the planetary roller screw pair in the technical background.

[0047] For this example, please refer to Figure 1 The input module 3 includes an input shaft 31, a spline connection component 32 and a locking component 33. The lead screw 11 and the input shaft 31 are relatively limited in radial and circumferential directions by the spline connection component 32. The locking component 33 is used to lock or disconnect the axial connection between the lead screw 11 and the spline connection component 32. When the lead screw pair moves normally, the locking component 33 locks the lead screw 11 and the spline connection component 32. When the lead screw pair is stuck, the locking component 33 disconnects the axial connection between the lead screw 11 and the spline connection component 32.

[0048] For this example, please refer to Figure 3 and Figure 4 , the locking component 33 comprises:

[0049] A hollow telescopic rod 331, one end of which is fixedly connected to the second sleeve 21, and a drop-out groove 332 is provided at the other end of the hollow telescopic rod 331, the lead screw 11 passes through the hollow telescopic rod 331 and is connected to the spline connection component 32, the hollow telescopic rod 331 is composed of three hollow sleeves, namely a first hollow sleeve 3311, a second hollow sleeve 3312 and a third hollow sleeve 3313, one end of the first hollow sleeve 3311 is fixedly connected to the second sleeve 21 by a screw, One end of the third hollow sleeve 3313 is provided with a drop-off groove 332, the first hollow sleeve 3311 is provided with a first slide groove, the second hollow sleeve 3312 is provided with a second protruding slider and a second slide groove, the third hollow sleeve 3313 is provided with a third protruding slider, the second protruding slider cooperates with the first slide groove, the third protruding slider cooperates with the second slide groove, the first hollow sleeve 3311, the second hollow sleeve 3312 and the third hollow sleeve 3313 constitute the hollow telescopic rod 331;

[0050] Through the design of the hollow telescopic rod 331, when the planetary roller screw pair with self-protection from jamming works normally, the hollow telescopic rod 331 stretches and retracts with the translation of the load ring 14, and the hollow telescopic rod 331 plays a role similar to a track; when the planetary roller screw pair with self-protection from jamming is jammed, the hollow telescopic rod 331 plays a role as a connecting piece;

[0051] A fixing ring 333, wherein the fixing ring 333 is installed between the hollow telescopic rod 331 and the spline connection component 32, the fixing ring 333 is fixedly connected to the external working platform, the lead screw 11 passes through the fixing ring 333, and the lead screw 11 and the fixing ring 333 are not connected;

[0052] A hook 334, wherein the hook 334 is mounted on the fixing ring 333, one end of the hook 334 and the inner wall of the hollow telescopic rod 331 are relatively limited in the axial and radial directions, and the other end of the hook 334 and the spline connection component 32 are relatively limited in the axial and radial directions. When the lead screw 11 is stuck, the hook 334 rotates relative to the hollow telescopic rod 331 and is unlocked from the hollow telescopic rod 331 through the drop-off groove 332, and the inner wall of the spline connection shaft 322 is provided with an annular groove 3221;

[0053] An elastic device is provided between the hook 334 and the fixing ring 333. One end of the hook 334 is provided with friction particles. The inner side of the other end of the hook 334 is hinged to the fixing ring 333 and a protrusion 3341 is provided on the outer side. When there is no pressure, due to the elastic device, the end of the hook 334 provided with the friction particles bounces outwards and the other end of the hook 334 drops. When there is pressure, the end of the hook 334 provided with the friction particles drops and the other end rises.

[0054] When one end of the hook 334 contacts the inner wall of the hollow telescopic rod 331, the friction particles ensure that the hollow telescopic rod 331 and the hook 334 do not move in the axial direction, and the inner wall of the hollow telescopic rod 331 presses down one end of the hook 334, and the other end of the hook 334 is lifted. At this time, the protrusion 3341 is stuck in the annular groove 3221, ensuring that the spline connecting shaft 322 does not fall off the fixing ring 333;

[0055] When jamming occurs, the drop-out groove 332 rotates to the position of the hook 334, and the hook 334 is disengaged from the inner wall of the hollow telescopic rod 331. At this time, one end of the hook 334 is lifted from the position of the drop-out groove 332, and the other end of the hook 334 is lowered, and the protrusion 3341 leaves the annular groove 3221, and the spline connecting shaft 322 and the fixing ring 333 are disengaged.

[0056] As described above, the hollow telescopic rod 331 connects the second sleeve 21 and the hook 334 on the fixing ring 333, thereby realizing the function of the second sleeve 21 rotating to drive the spline connecting shaft 322 and the lead screw 11 to separate.

[0057] For this example, please refer to Figure 1 and Figure 4 The spline connection component 32 includes an internal spline hollow shaft 321 and a spline connection shaft 322, one end of the internal spline hollow shaft 321 is fixedly connected to the input shaft 31, the other end of the internal spline hollow shaft 321 and one end of the spline connection shaft 322 are relatively limited in radial and circumferential directions by a spline structure, and the other end of the spline connection shaft 322 and the lead screw 11 are relatively limited in radial and circumferential directions by a spline structure. Through the internal spline hollow shaft 321 and the spline connection shaft 322, the rotation of the input shaft 31 can be transmitted to the lead screw 11, thereby driving the lead screw 11 to rotate, and when the lead screw 11 and the roller 12 are stuck, the connection between the input shaft 31 and the lead screw 11 can be disconnected in time through the cooperation of the locking component 33 and the spline connection shaft 322 and the internal spline hollow shaft 321 described below.

[0058] For this example, please refer to Figure 3 and Figure 4 , and also includes: a tensioning spring 335, one end of which is fixedly connected to the spline connecting shaft 322, and the other end of which is fixedly connected to the inner spline hollow shaft 321, and the tensioning spring 335 pulls the spline connecting shaft 322 to move axially by a distance greater than the axial connection length between the spline connecting shaft 322 and the lead screw 11. When the lead screw pair is working normally, the spline connecting shaft 322 and the hollow telescopic rod 331 are fixedly connected together, and the tensioning spring 335 is in a stretched state. When jamming occurs, the connection between the spline connecting shaft 322 and the hollow telescopic rod 331 is unlocked, and the tensioning spring 335 gradually retracts from the stretched state, thereby pulling the spline connecting shaft 322 and the lead screw 11 out of contact, and finally achieving the purpose of disconnecting the input shaft 31 and the lead screw 11.

[0059] For this example, please refer to Figure 4 A buffer spring 336 is provided between the spline connecting shaft 322 and the inner spline hollow shaft 321 to prevent collision between the spline connecting shaft 322 and the inner spline hollow shaft 321 during the retraction of the tension spring 335 .

[0060] For this example, please refer to Figure 3 and Figure 5 A snap-fit ​​component 34 is provided at one end of the spline connecting shaft 322. When jamming occurs, the lead screw 11 and the spline connecting shaft 322 are disconnected, and the spline connecting shaft 322 and the internal spline hollow shaft 321 are axially limited to each other by the snap-fit ​​component 34.

[0061] For this example, please refer to Figure 3 and Figure 5 A slide groove 341 is provided on the inner wall of the inner spline hollow shaft 321, and a groove 342 is provided at the end of the slide groove 341, and the groove 342 passes through the inner spline hollow shaft 321;

[0062] The buckle component 34 includes a buckle 343, a buckle spring 344 and a telescopic slot 345. The buckle spring 344 is fixedly installed in the telescopic slot 345. The rebound and contraction directions of the buckle spring 344 are along the radial direction of the lead screw 11. One end of the buckle 343 is fixedly connected to the buckle spring 344 and is located in the telescopic slot 345. The other end of the buckle 343 is located outside the telescopic slot 345. After the buckle 343 slides along the slide slot 341 into the groove 342, the spline connecting shaft 322 and the inner spline hollow shaft 321 are locked.

[0063] Through the design of the snap component 34, when jamming occurs, after the spline connecting shaft 322 and the lead screw 11 are disconnected, the snap 343 can be stuck in the groove 342, avoiding the rebound of the tension spring 335, causing the spline connecting shaft 322 and the lead screw 11 to be connected again when the jamming fault is not eliminated. After the jamming fault is eliminated, it is necessary to press the snap 343 and then pull the spline connecting shaft 322 to connect the spline connecting shaft 322 and the lead screw 11 together again.

[0064] For this example, please refer to Figure 1 and Figure 2 The redundant module 2 includes a second sleeve 21, a raceway 22 and a ball 23. The inner wall of the second sleeve 21 wraps around the outer wall of the first sleeve 13. The first sleeve 13 and the second sleeve 21 are fixedly connected together. The first sleeve 13 and the second sleeve 21 are detachable. The raceway 22 is continuously arranged on the outer wall of the second sleeve 21 in an axial spiral shape. The ball 23 is arranged on the inner wall of the load ring 14. The ball 23 rolls along the raceway 22. The second sleeve 21 is coaxial with the screw 11. When the screw pair moves normally, the friction between the ball 23 and the raceway 22 ensures that the ball 23 does not roll. When the screw pair is stuck, the rotation of the first sleeve 13 drives the rotation of the second sleeve 21, and the ball 23 is acted upon by force to roll along the raceway 22. This structure can be understood as a ball screw pair being put on the outside of the original planetary roller screw pair, and the original planetary roller screw pair as a whole acts as a new "screw".

[0065] For this example, please refer to Figure 2 , further comprising two retaining frames 15, the two retaining frames 15 are respectively mounted at both ends of the first sleeve 13, and the two ends of the roller 12 are rotatably connected to the two retaining frames 15;

[0066] The inner wall of the first sleeve 13 is provided with threads, and the roller 12 is meshed with the inner wall of the first sleeve 13 to play a role in transmitting force.

[0067] For this example, please refer to Figure 2 , further comprising two inner gear rings 16, the two inner gear rings 16 are respectively fixedly mounted at two ends of the first sleeve 13, and the inner gear rings 16 are coaxial with the lead screw 11;

[0068] A coaxial outer gear ring 17 is disposed at each end of the roller 12, and the outer gear ring 17 and the inner gear ring 16 on the same side are meshed;

[0069] Through the design of the inner gear ring 16 and the outer gear ring 17, the tilting moment caused by the helix angle of the screw 11 on the roller 12 can be eliminated, ensuring that the axis of the roller 12 rolls normally parallel to the axis of the screw 11.

[0070] For this example, please refer to Figure 2 , and also includes a spring snap ring 18, which is installed between the retaining frame 15 and the inner gear ring 16 to increase the stability of the screw pair during operation.

[0071] See also Figures 1 to 5 The present invention provides a method for using a planetary roller screw pair with self-protection from sticking as described above, comprising the following steps:

[0072] Normal movement of the screw pair: the input shaft 31 is driven to rotate by the power provided by the motor, the screw 11 is driven to rotate by the internal spline hollow shaft 321 and the spline connecting shaft 322, and the rotational movement of the screw 11 is converted into the translational movement of the first sleeve 13, the second sleeve 21 and the load ring 14 through the matching relationship between the screw 11, the roller 12 and the first sleeve 13, the hollow telescopic rod 331 stretches or retracts with the translation of the second sleeve 21, the hook 334 fixes the hollow telescopic rod 331 and the spline connecting shaft 322 together, and the spline connecting shaft 322 and the screw 11 are also mutually limited by the spline structure;

[0073] Troubleshooting after jamming occurs: When jamming occurs between the lead screw 11 and the roller 12, the roller 12 stops rotating around the lead screw 11, and instead rotates with the lead screw 11 but does not rotate on its own, and rotates with the first sleeve 13 and the second sleeve 21. As the second sleeve 21 rotates, due to the cooperation between the ball 23 on the inner wall of the load ring 14 and the raceway 22 on the outer wall of the second sleeve 21, the second sleeve 21 rotates out of the load ring 14 and rotates with the hollow telescopic rod 331. When the drop-off groove 332 rotates to the position of the hook 334, under the action of the tension spring 335, the lead screw 11 and the spline connection shaft 322 move away from each other in the axial direction.

[0074] As the spline connecting shaft 322 moves in the axial direction, the screw 11 and the spline connecting shaft 322 are separated from each other, the buckle 343 slides into the groove 342, and the spline connecting shaft 322 and the inner spline hollow shaft 321 are fixed to each other due to the cooperation between the buckle 343 and the groove 342, and the rotation of the screw 11 stops;

[0075] Remove the load ring 14, replace the lead screw 11, the roller 12, the first sleeve 13, the second sleeve 21 and the hollow telescopic rod 331 as a whole, and send the replaced parts for repair;

[0076] Resume movement: install the replaced parts, press the buckle 343 in the groove 342, connect the spline connecting shaft 322 and the hollow telescopic rod 331 together, rotate the hollow telescopic rod 331, ensure that the position of the hook 334 and the position of the drop-off groove 332 are staggered, and at this time, the spline connecting shaft 322 and the lead screw 11 are again limited to each other by the spline structure, and power is provided again to drive the input shaft 31 to rotate and drive the lead screw 11 to rotate. The rotation of the lead screw 11 drives the first sleeve 13, the second sleeve 21 and the load ring 14 to perform translational movement.

[0077] In summary, the present invention realizes the function of meshing the inner wall of the load ring 14 and the outer wall of the first sleeve 13 through the design of the redundant module 2. When the lead screw 11 and the roller 12 are stuck, because the load ring 14 and the first sleeve 13 are meshed, the load ring 14 will not generate too much resistance torque on the lead screw 11. At the same time, after the jamming occurs, the first sleeve 13 will rotate around the axis of the lead screw 11 to drive the input module 3 to disengage from the lead screw 11 in time, so as to avoid the lead screw 11 from being stuck and the continuous rotation of the lead screw 11 generating excessive torque, causing the lead screw 11 to break and other irreversible damages. At the same time, through the design of the hollow telescopic rod 331, when the planetary roller screw pair with self-protection from jamming works normally, the hollow telescopic rod 331 stretches and retracts with the translation of the load ring 14, and the hollow telescopic rod 331 plays a role similar to that of a track. The function of the present invention is to make the spline connecting shaft 322 and the lead screw 11 to be disconnected after the spline connecting shaft 322 and the lead screw 11 are disconnected when the spline connecting shaft 322 and the lead screw 11 are disconnected. Therefore, the present invention effectively overcomes various shortcomings in the prior art and has high industrial utilization value.

[0078] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A planetary roller screw pair with self-protection from jamming, characterized in that: include: A lead screw, a roller and a first sleeve, wherein the rollers are radially arranged around the lead screw and are enclosed by the first sleeve, the lead screw passes through the first sleeve and meshes with the rollers, the rollers and the first sleeve are rotatably connected, the rollers and the first sleeve are relatively limited in the axial direction of the lead screw, the lead screw and the first sleeve are coaxial, and the central axis of the rollers and the central axis of the lead screw are parallel to each other; A load ring and a redundant module, wherein the redundant module connects the inner wall of the load ring and the outer wall of the first sleeve in a ball screw pair; An input module, wherein the input module and the lead screw are detachably connected; Rotation of the first sleeve about the lead screw axis drives the input module to disengage from the lead screw.

2. A planetary roller screw pair with self-protection from jamming according to claim 1, characterized in that: The input module includes an input shaft, a spline connection component and a locking component. The lead screw and the input shaft are relatively limited in radial and circumferential directions by the spline connection component. The locking component is used to lock or disconnect the axial connection between the lead screw and the spline connection component.

3. A planetary roller screw pair with self-protection from jamming according to claim 2, characterized in that: The locking component comprises: A hollow telescopic rod, one end of which is fixedly connected to the first sleeve, the other end of which is provided with a drop-out groove, the lead screw passes through the hollow telescopic rod and is connected to the spline connection component; A fixing ring, the fixing ring being installed between the hollow telescopic rod and the spline connection component, the fixing ring being fixedly connected to the external working platform, and the lead screw passing through the fixing ring; A hook, wherein the hook is mounted on the fixing ring, one end of the hook and the inner wall of the hollow telescopic rod are relatively limited in the axial and radial directions, and the other end of the hook and the spline connection component are relatively limited in the axial and radial directions. When the lead screw is stuck, the hook rotates relative to the hollow telescopic rod and is unlocked from the hollow telescopic rod through the drop-out groove.

4. A planetary roller screw pair with self-protection from jamming according to claim 2, characterized in that: The spline connection component includes an internal spline hollow shaft and a spline connection shaft, one end of the internal spline hollow shaft is fixedly connected to the input shaft, the other end of the internal spline hollow shaft and one end of the spline connection shaft are relatively limited in radial and circumferential directions by a spline structure, and the other end of the spline connection shaft and the lead screw are relatively limited in radial and circumferential directions by a spline structure.

5. A planetary roller screw pair with self-protection from jamming according to claim 4, characterized in that: Also includes: A tensioning spring, one end of which is fixedly connected to the spline connecting shaft, and the other end of which is fixedly connected to the inner spline hollow shaft, and the tensioning spring pulls the spline connecting shaft to move axially a distance greater than the axial connection length between the spline connecting shaft and the lead screw.

6. A planetary roller screw pair with self-protection from jamming according to claim 4, characterized in that: A buffer spring is arranged between the spline connecting shaft and the internal spline hollow shaft.

7. A planetary roller screw pair with self-protection from jamming according to claim 4, characterized in that: A snap-fit ​​component is provided at one end of the spline connecting shaft. When jamming occurs, the lead screw and the spline connecting shaft are disconnected, and the spline connecting shaft and the internal spline hollow shaft are axially limited to each other by the snap-fit ​​component.

8. A planetary roller screw pair with self-protection from jamming according to claim 7, characterized in that: A slide groove is provided on the inner wall of the internal spline hollow shaft, and a groove is provided at the end of the slide groove, and the groove passes through the internal spline hollow shaft; The buckle component includes a buckle, a buckle spring and a telescopic slot, the buckle spring is fixedly installed in the telescopic slot, the rebound and contraction directions of the buckle spring are along the radial direction of the lead screw, one end of the buckle is fixedly connected to the buckle spring and is located in the telescopic slot, and the other end of the buckle is located outside the telescopic slot, and after the buckle slides along the slide slot into the groove, the spline connecting shaft and the inner spline hollow shaft are locked.

9. A planetary roller screw pair with self-protection from jamming according to claim 1, characterized in that: The redundant module includes a second sleeve, a raceway and a ball. The inner wall of the second sleeve wraps around the outer wall of the first sleeve. The first sleeve and the second sleeve are fixedly connected together. The first sleeve and the second sleeve are detachable. The raceway is continuously arranged on the outer wall of the second sleeve in an axial direction in a spiral shape. The ball is located between the second sleeve and the load ring. When the first sleeve rotates around the axis of the screw, the ball is driven to roll along the raceway. The second sleeve and the screw are coaxial.

10. A method for using a planetary roller screw pair with self-protection from jamming according to claim 1, characterized in that: The steps include: Normal movement of the lead screw pair: the input module drives the lead screw to rotate, and the rotational movement of the lead screw is converted into the translational movement of the load ring through the lead screw pair; Troubleshooting after jamming occurs: the roller stops rotating around the lead screw, and instead rotates with the lead screw but does not rotate on its own, and rotates with the first sleeve, and finally drives the input module to detach from the lead screw, the rotation of the lead screw stops, the load ring is removed, and the jammed parts are sent for repair; Restoring motion: Install the replaced parts, connect the input module and the lead screw together, and the input module drives the lead screw to rotate again, and converts it into translational motion of the load ring.

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