Anti-backout nut assembly

Abstract

This invention discloses a backlash-eliminating nut assembly, comprising a lead screw, a first nut, a second nut, a limiting member, and an elastic tightening member. Both the second nut and the first nut are disposed on the lead screw and are rotatable relative to it. The limiting member is positioned between the second nut and the first nut, and the second nut and the first nut can slide along the axial direction of the lead screw via the limiting member, allowing the second nut and the first nut to move relative to each other along the axial direction of the lead screw. The elastic tightening member is disposed between the second nut and the first nut and is retractable relative to the lead screw, pushing the second nut and / or the first nut along the axial direction of the lead screw. In this embodiment of the invention, the elastic tightening member of the backlash-eliminating nut assembly automatically extends, pushing the first nut and / or the second nut along the axial direction of the lead screw, ensuring that the threaded surfaces of the first nut and / or the second nut are always in close contact with both sides of the lead screw thread, thereby eliminating axial backlash.

Description

Technical Field

[0001] This invention relates to the field of mechanical transmission technology, and specifically to a backlash-free nut assembly. Background Technology

[0002] In related lead screw and nut transmission mechanisms, due to factors such as machining errors, wear, and thermal deformation, there is often an axial clearance between the internal thread of the nut and the external thread of the lead screw. This clearance can lead to return error, reduced positioning accuracy, and slow dynamic response in the transmission system. It can also generate impact and vibration during reversal, affecting the working accuracy and stability of the equipment. The clearance elimination methods in related technologies include double nut preload and elastic shim adjustment, but most of them are complex in structure, inconvenient to adjust, and difficult to achieve automatic clearance compensation during use. Summary of the Invention

[0003] The present invention aims to at least partially solve one of the technical problems in the related art.

[0004] Therefore, embodiments of the present invention propose a backlash-eliminating nut assembly in which the elastic clamping component automatically extends and pushes the first nut and / or the second nut along the screw axial direction, so that the threaded surfaces of the first nut and / or the second nut are always in close contact with both sides of the screw thread, thereby eliminating axial backlash.

[0005] The backlash-free nut assembly of this invention includes a lead screw, a first nut, a second nut, a limiting member, and an elastic clamping member. Both the second nut and the first nut are disposed on the lead screw and are rotatable relative to it. The limiting member is positioned between the second nut and the first nut, and the second nut and the first nut can slide along the axial direction of the lead screw via the limiting member, allowing the second nut and the first nut to move relative to each other along the axial direction of the lead screw. The elastic clamping member is disposed between the second nut and the first nut and is retractable relative to the lead screw to push the second nut and / or the first nut along the axial direction of the lead screw.

[0006] By mounting a first nut and a second nut on a lead screw and allowing them to rotate relative to the screw, while simultaneously using a limiting component to enable relative movement of the first and second nuts along the axial direction of the lead screw, a structure is formed that allows axial movement but restricts the circumferential rotation of the first and second nuts. An elastic clamping component is positioned between the first and second nuts and can extend and retract relative to the lead screw, thereby generating a continuous axial thrust. When the first nut and / or the second nut develops a gap due to wear, the elastic clamping component automatically extends, pushing the first nut and / or the second nut along the axial direction of the lead screw, ensuring that the threaded surfaces of the first nut and / or the second nut are always in close contact with both sides of the lead screw thread, thus eliminating the axial gap. This achieves an automatic dynamic gap elimination function, continuously compensating for gap increases caused by wear and other factors without manual intervention.

[0007] In some embodiments, the elastic clamping member of the backlash-free nut assembly of the present invention includes a spring disposed between the second nut and the first nut and sleeved on the lead screw, and the spring extends and retracts relative to the lead screw to push the second nut and / or the first nut along the axial direction of the lead screw.

[0008] In some embodiments, the spring of the backlash-free nut assembly of the present invention is a ring torsion spring, and the elastic tightening component further includes a sleeve and a blocking member; the sleeve is located between the second nut and the first nut and is sleeved between the ring torsion spring and the portion of the second nut, the first end of the ring torsion spring is connected to the first nut, the second end of the ring torsion spring is connected to the inner sidewall of the sleeve, the sleeve is rotatable relative to the lead screw, so that when the sleeve rotates relative to the lead screw, the sleeve can drive the ring torsion spring to rotate relative to the lead screw; the blocking member is disposed between the sleeve and the second nut, so that when the sleeve rotates relative to the lead screw, the blocking member can block the rotation of the sleeve and the ring torsion spring, so that the ring torsion spring can push the second nut and / or the first nut along the axial direction of the lead screw.

[0009] In some embodiments of the invention, the annular torsion spring of the backlash-free nut assembly is made of spring steel.

[0010] In some embodiments, the blocking member of the gap-eliminating nut assembly of the present invention is a blocking block. The blocking block is disposed at the end of the outer wall of the second nut away from the first nut. The end of the sleeve away from the first nut has a slot. A portion of the blocking block is placed in the slot so that the blocking block blocks the sleeve and the annular torsion spring from rotating.

[0011] In some embodiments of the present invention, the first end of the annular torsion spring of the backlash-free nut assembly extends along the sleeve toward the first nut and is connected to the first nut, the second end of the annular torsion spring extends along the radial direction of the lead screw, the side wall of the sleeve has a through hole, and the second end of the annular torsion spring can fit into the through hole.

[0012] In some embodiments, the limiting member of the backlash-free nut assembly of the present invention is a limiting block. The limiting block is disposed at one end of the first nut near the second nut. The second nut has a limiting groove. At least a portion of the limiting block can be fitted into the limiting groove. The limiting block can be movable relative to the lead screw along the axial direction of the lead screw within the limiting groove.

[0013] In some embodiments, the backlash-eliminating nut assembly of the present invention comprises multiple limiting blocks and multiple limiting grooves, with each limiting block and multiple limiting grooves corresponding one-to-one. The multiple limiting blocks are arranged at intervals along the circumference of the second nut, and the multiple limiting grooves are arranged at intervals along the circumference of the first nut.

[0014] In some embodiments, the outer side wall of the first nut of the backlash-free nut assembly of the present invention has external threads.

[0015] In some embodiments, the outer wall of the first nut of the backlash-free nut assembly of the present invention has at least two horizontal portions, the at least two horizontal portions being arranged radially opposite to each other along the lead screw. Attached Figure Description

[0016] Figure 1 This is an exploded view of the overall structure of the gap-reducing nut assembly according to an embodiment of the present invention.

[0017] Figure label:

[0018] 100. Clearance-eliminating nut assembly; 1. Lead screw; 2. First nut; 201. External thread; 202. Horizontal part; 3. Second nut; 301. Limiting groove; 4. Limiting component; 401. Limiting block; 5. Elastic clamping component; 501. Spring; 5011. Ring torsion spring; 502. Sleeve; 5021. Slot; 5022. Perforation; 503. Blocking component; 5031. Blocking block. Detailed Implementation

[0019] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0020] Reference Figure 1 The backlash-free nut assembly 100 of this embodiment includes a lead screw 1, a first nut 2, a second nut 3, a limiting member 4, and an elastic pressing member 5. The second nut 3 and the first nut 2 are both disposed on the lead screw 1 and are rotatable relative to the lead screw 1. The limiting member 4 is positioned between the second nut 3 and the first nut 2, and the second nut 3 and the first nut 2 can slide along the axial direction of the lead screw 1 via the limiting member 4, allowing the second nut 3 and the first nut 2 to move relative to each other along the axial direction of the lead screw 1. The elastic pressing member 5 is disposed between the second nut 3 and the first nut 2 and is telescopic relative to the lead screw 1 to push the second nut 3 and / or the first nut 2 along the axial direction of the lead screw 1.

[0021] By mounting the first nut 2 and the second nut 3 on the lead screw 1 and allowing them to rotate relative to the lead screw 1, while simultaneously using a limiting member 4 to enable relative movement of the first nut 2 and the second nut 3 along the axial direction of the lead screw 1, a structure is formed that allows axial movement but restricts the circumferential rotation of the first nut 2 and the second nut 3. An elastic clamping member 5 is positioned between the first nut 2 and the second nut 3 and can extend and retract relative to the lead screw 1, thereby generating a continuous axial pushing force. When the first nut 2 and / or the second nut 3 develops a gap due to wear, the elastic clamping member 5 automatically extends, pushing the first nut 2 and / or the second nut 3 along the axial direction of the lead screw 1, ensuring that the threaded surfaces of the first nut 2 and / or the second nut 3 are always in close contact with both sides of the thread of the lead screw 1, thus eliminating the axial gap. This achieves an automatic dynamic gap elimination function, continuously compensating for gap increases caused by wear and other factors without manual intervention.

[0022] In some embodiments, such as Figure 1 The elastic clamping component 5 of the backlash-free nut assembly 100 in this embodiment of the invention includes a spring 501. The spring 501 is disposed between the second nut 3 and the first nut 2 and sleeved on the lead screw 1. The spring 501 extends and retracts relative to the lead screw 1 to push the second nut 3 and / or the first nut 2 along the axial direction of the lead screw 1.

[0023] Spring 501 is sleeved on lead screw 1 and located between second nut 3 and first nut 2, allowing spring 501 to axially extend and retract relative to lead screw 1, thereby generating a continuous axial thrust. When gaps occur between first nut 2 and / or second nut 3 during operation, spring 501 applies an axial preload to first nut 2 and / or second nut 3 through its own elastic deformation, ensuring that the threaded surfaces of first nut 2 and / or second nut 3 are in close contact with both sides of the thread on lead screw 1, eliminating axial gaps. As wear occurs during equipment use, causing the gaps to increase, spring 501 automatically elongates to compensate for this change.

[0024] In some embodiments, such as Figure 1In this embodiment of the invention, the spring 501 of the backlash-free nut assembly 100 is a ring torsion spring 5011, and the elastic pressing component 5 further includes a sleeve 502 and a blocking member 503. The sleeve 502 is located between the second nut 3 and the first nut 2, and the sleeve 502 is sleeved between the ring torsion spring 5011 and the portion of the second nut 3. The first end of the ring torsion spring 5011 is connected to the first nut 2, and the second end of the ring torsion spring 5011 is connected to the inner wall of the sleeve 502. The sleeve 502 is rotatable relative to the lead screw 1, so that when the sleeve 502 rotates relative to the lead screw 1, the sleeve 502 can drive the ring torsion spring 5011 to rotate relative to the lead screw 1. The blocking member 503 is disposed between the sleeve 502 and the second nut 3, so that when the sleeve 502 rotates relative to the lead screw 1, the blocking member 503 can block the rotation of the sleeve 502 and the ring torsion spring 5011, so that the ring torsion spring 5011 can push the second nut 3 and / or the first nut 2 along the axial direction of the lead screw 1.

[0025] The first end of the annular torsion spring 5011 is fixedly connected to the first nut 2, and the second end is connected to the inner wall of the sleeve 502. The sleeve 502 can rotate relative to the lead screw 1. Rotating the sleeve 502 causes the annular torsion spring 5011 to twist and store elastic potential energy. When the sleeve 502 continues to rotate to a certain extent, the blocking member 503 will block the further rotation of the sleeve 502 and the annular torsion spring 5011, thereby converting the torsional restoring force of the torsion spring into an axial thrust. The sleeve 502 pushes the second nut 3 and / or the first nut 2 to move axially along the lead screw 1, thereby eliminating axial clearance. In this way, the torsional force of the annular torsion spring 5011 can be converted into an axial preload, which facilitates automatic compensation.

[0026] In some embodiments, such as Figure 1 In this embodiment of the invention, the annular torsion spring 5011 of the backlash-eliminating nut assembly 100 is made of spring steel 501. Spring steel 501 has excellent elastic properties and fatigue strength, and can maintain stable elasticity and restoring force during long-term use. When the annular torsion spring 5011 is torn, the spring steel material can store and release stable elastic potential energy, generating a continuous and reliable axial preload, pushing the second nut 3 and / or the first nut 2 to move axially along the screw 1, thereby eliminating the axial gap between the second nut 3 and / or the first nut 2 and the screw 1.

[0027] In some embodiments, such as Figure 1 In this embodiment of the invention, the blocking member 503 of the gap-eliminating nut assembly 100 is a blocking block 5031. The blocking block 5031 is located on the outer side wall of the second nut 3 away from the first nut 2. The sleeve 502 away from the first nut 2 has a slot 5021. A portion of the blocking block 5031 is placed in the slot 5021 so that the blocking block 5031 blocks the sleeve 502 and the annular torsion spring 5011 from rotating.

[0028] The blocking block 5031 is located at the end of the outer wall of the second nut 3 away from the first nut 2, and forms a mating structure with the slot 5021 on the sleeve 502. When the sleeve 502 rotates to a certain extent, the blocking block 5031 is engaged in the slot 5021 to prevent the sleeve 502 and the annular torsion spring 5011 from rotating, thereby converting the torsional force of the torsion spring into an axial thrust, pushing the second nut 3 and / or the first nut 2 to move to eliminate the axial clearance.

[0029] In some embodiments, such as Figure 1 In this embodiment of the invention, the first end of the annular torsion spring 5011 of the backlash-free nut assembly 100 extends along the sleeve 502 toward the first nut 2, and the first end of the annular torsion spring 5011 is connected to the first nut 2. The second end of the annular torsion spring 5011 extends along the radial direction of the lead screw 1. The side wall of the sleeve 502 has a through hole 5022, and the second end of the annular torsion spring 5011 can be fitted into the through hole 5022.

[0030] In this way, the annular torsion spring 5011 can convert rotational motion into axial force. When the sleeve 502 rotates, the engagement between the through hole 5022 and the second end of the torsion spring restricts the radial movement of the annular torsion spring 5011, forcing the annular torsion spring 5011 to undergo axial deformation, thereby generating axial preload to eliminate the gap between the second nut 3 and / or the first nut 2.

[0031] In some embodiments, such as Figure 1 In this embodiment of the invention, the limiting member 4 of the backlash-free nut assembly 100 is a limiting block 401. The limiting block 401 is disposed at one end of the first nut 2 near the second nut 3. The second nut 3 has a limiting groove 301. At least a portion of the limiting block 401 can be fitted into the limiting groove 301. The limiting block 401 can move relative to the lead screw 1 along the axial direction of the lead screw 1 within the limiting groove 301.

[0032] The limiting block 401 is located at one end of the first nut 2 near the second nut 3, forming a mating structure with the limiting groove 301 on the second nut 3, so that the limiting block 401 can slide along the axial direction of the screw 1 in the limiting groove 301, while restricting the relative rotation between the second nut 3 and the first nut 2, so that the axial clearance between the first nut 2 and the second nut 3 in the axial direction of the screw 1 can be eliminated.

[0033] In some embodiments, such as Figure 1 In this embodiment of the invention, the gap-eliminating nut assembly 100 has multiple limiting blocks 401 and multiple limiting grooves 301. The multiple limiting blocks 401 and multiple limiting grooves 301 correspond one-to-one. The multiple limiting blocks 401 are arranged at intervals along the circumference of the second nut 3, and the multiple limiting grooves 301 are arranged at intervals along the circumference of the first nut 2.

[0034] By cooperating with multiple limiting blocks 401 and limiting grooves 301, axial sliding constraint between the first nut 2 and the second nut 3 is achieved, while ensuring uniform force distribution and avoiding local wear or deformation caused by excessive force at a single point.

[0035] In some embodiments, such as Figure 1 In this embodiment of the invention, the outer side wall of the first nut 2 of the backlash-free nut assembly 100 has an external thread 201. The external thread 201 can be used for positioning and connection with an external mechanism.

[0036] In some embodiments, such as Figure 1 In this embodiment of the invention, the outer wall of the first nut 2 of the backlash-free nut assembly 100 has at least two horizontal portions 202, which are arranged opposite each other radially along the lead screw 1. The arrangement of the two horizontal portions 202 facilitates the tightening of the first nut 2 by hand-held wrench.

[0037] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element 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 this invention.

[0038] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0039] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0040] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0041] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0042] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A backlash-free nut assembly, characterized in that, include: Lead screw (1); The first nut (2) and the second nut (3) are both located on the lead screw (1) and are rotatable relative to the lead screw (1); The limiting member (4) is connected between the second nut (3) and the first nut (2), and the second nut (3) and the first nut (2) can slide along the axial direction of the screw (1) through the limiting member (4) so ​​that the second nut (3) and the first nut (2) can move relative to each other along the axial direction of the screw (1); An elastic clamping member (5) is disposed between the second nut (3) and the first nut (2) and is telescopic relative to the lead screw (1) to push the second nut (3) and / or the first nut (2) along the axial direction of the lead screw (1).

2. The backlash-free nut assembly according to claim 1, characterized in that, The elastic clamping component (5) includes a spring (501) disposed between the second nut (3) and the first nut (2) and sleeved on the lead screw (1), and the spring (501) extends and retracts relative to the lead screw (1) to push the second nut (3) and / or the first nut (2) along the axial direction of the lead screw (1).

3. The backlash-free nut assembly according to claim 2, characterized in that, The spring (501) is a ring torsion spring (5011), and the elastic pressing component (5) further includes: A sleeve (502) is located between the second nut (3) and the first nut (2) and is sleeved between the annular torsion spring (5011) and the second nut (3). The first end of the annular torsion spring (5011) is connected to the first nut (2), and the second end of the annular torsion spring (5011) is connected to the inner wall of the sleeve (502). The sleeve (502) is rotatable relative to the lead screw (1) so that when the sleeve (502) rotates relative to the lead screw (1), the sleeve (502) can drive the annular torsion spring (5011) to rotate relative to the lead screw (1). A blocking member (503) is provided between the sleeve (502) and the second nut (3) so that when the sleeve (502) rotates relative to the lead screw (1), the blocking member (503) can block the sleeve (502) and the annular torsion spring (5011) from rotating, so that the annular torsion spring (5011) can push the second nut (3) and / or the first nut (2) along the axial direction of the lead screw (1).

4. The backlash-free nut assembly according to claim 3, characterized in that, The annular torsion spring (5011) is made of spring (501) steel.

5. The backlash-free nut assembly according to claim 3, characterized in that, The blocking member (503) is a blocking block (5031). The blocking block (5031) is located on the outer side wall of the second nut (3) at one end away from the first nut (2). The sleeve (502) has a slot (5021) at one end away from the first nut (2). A portion of the blocking block (5031) is placed in the slot (5021) so that the blocking block (5031) blocks the sleeve (502) and the annular torsion spring (5011) from rotating.

6. The backlash-free nut assembly according to claim 3, characterized in that, The first end of the annular torsion spring (5011) extends along the sleeve (502) toward the first nut (2), and the first end of the annular torsion spring (5011) is connected to the first nut (2). The second end of the annular torsion spring (5011) extends along the radial direction of the lead screw (1). The side wall of the sleeve (502) has a through hole (5022), and the second end of the annular torsion spring (5011) can fit into the through hole (5022).

7. The backlash-free nut assembly according to claim 1, characterized in that, The limiting member (4) is a limiting block (401). The limiting block (401) is located at one end of the first nut (2) near the second nut (3). The second nut (3) has a limiting groove (301). At least a portion of the limiting block (401) can be fitted into the limiting groove (301). The limiting block (401) can move relative to the lead screw (1) along the axial direction of the lead screw (1) within the limiting groove (301).

8. The backlash-free nut assembly according to claim 7, characterized in that, There are multiple limiting blocks (401) and multiple limiting grooves (301). The multiple limiting blocks (401) and multiple limiting grooves (301) correspond one-to-one. The multiple limiting blocks (401) are arranged at intervals along the circumference of the second nut (3), and the multiple limiting grooves (301) are arranged at intervals along the circumference of the first nut (2).

9. The backlash-free nut assembly according to claim 1, characterized in that, The outer wall of the first nut (2) has an external thread (201).

10. The backlash-free nut assembly according to any one of claims 1-9, characterized in that, The outer wall of the first nut (2) has at least two horizontal portions (202) arranged opposite each other along the radial direction of the lead screw (1).

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