A self-unlocking anti-backlash screw drive assembly

Abstract

The present invention discloses a self-unlocking and backlash-eliminating screw drive assembly, which relates to the technical field of screw transmission, and includes a driving screw, a moving module, a locking member, an unlocking member and a guide member. When the present invention is used, the locking member applies forces to two nuts respectively, so that the two nuts move in directions away from or close to each other, that is, the locking member causes the two nuts to apply pre-tightening pressures in opposite directions to the screw threads respectively, thereby eliminating the gap between the moving module and the screw threads. When driving, according to the driving direction, the unlocking member applies a driving force in the opposite direction of the force to the nuts in the moving direction of the moving module, so as to offset the pre-tightening pressure in the driving direction, thereby achieving the purpose of unlocking. Even if the pre-tightening force is too large, the transmission efficiency will not be reduced, so that the moving module can easily move in the driving direction.

Description

Technical Field

[0001] The invention relates to the technical field of screw drive, in particular to a self-unlocking anti-backlash screw drive assembly. Background Art

[0002] Screw drive is a commonly used rotation-linear motion transmission mechanism. This type of transmission generally uses a method of pre-tightening multiple nuts to eliminate backlash or reducing the fit clearance. When using a double-nut pre-tightening and backlash elimination scheme, there is a pair of contradictions in the selection of pre-tightening force. If the pre-tightening force is too small, the critical load for re-generating the gap will be small; if the pre-tightening force is too large, the transmission efficiency will be significantly reduced. When using a solution to reduce the fit clearance, such as the fit of unequal pitch screw nuts, the transmission clearance is small and the friction resistance is large during initial installation. After the mechanism wears, the friction resistance decreases, but the transmission clearance will reappear.

[0003] In view of this, there is an urgent need for a self-unlocking anti-backlash screw drive assembly. Summary of the invention

[0004] In view of the problems existing in the prior art, the present invention solves the problems with the following technical structure.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] A self-unlocking anti-backlash screw drive assembly, comprising: a driving screw, a moving module, a locking member, an unlocking member and a guide member, wherein the guide member is used to guide the movement of the moving module so that the moving module performs translational movement;

[0007] The moving module includes two submodules, each of which includes a nut, and both of the nuts are sleeved on the driving screw and threadedly connected to the driving screw;

[0008] The locking member is used to apply a force along the axial direction of the driving screw to the two nuts respectively, and the force of the locking member causes the two nuts to move to the sides away from each other respectively;

[0009] The unlocking member is used to apply a driving force opposite to the direction of the applied force to one of the nuts.

[0010] It is further characterized in that

[0011] The guide member comprises two guide rods, and the two ends of the moving module are respectively sleeved on the two guide rods, and the axial direction of the guide rod is consistent with the axial direction of the driving screw rod.

[0012] The submodule further comprises a moving seat, the nut is arranged on the moving seat, two ends of the moving seat respectively extend to the bottom and the top of the two guide rods, and the two moving seats are cross-arranged in a scissor shape.

[0013] Grooves are arranged on one side of both ends of the moving seat close to the two guide rods.

[0014] The unlocking member includes an unlocking screw and a slider, the slider is slidably arranged between the two moving seats, the unlocking screw passes through the slider and is threadedly connected to the slider, the unlocking screw rotates to make the slider move along the axial direction of the unlocking screw, and the axial direction of the unlocking screw is consistent with that of the driving screw;

[0015] The two moving seats are both provided with abutment end surfaces, and the two abutment end surfaces are respectively arranged on both sides of the moving direction of the slider.

[0016] The sides of the movable seats that are close to each other are each provided with a slide groove, and the two ends of the slider are respectively slidably arranged in the slide groove, the two slide grooves are axially staggered in the unlocking screw rod, and the sides of the two slide grooves that are away from each other are the abutment end faces.

[0017] The movable seats are all provided with sleeve rings, which are sleeved on the ring side of the unlocking screw rod.

[0018] The transmission ratio of the unlocking screw rod is smaller than the transmission ratio of the driving screw rod.

[0019] The locking member is an elastic member, and the elastic member is arranged between two nuts.

[0020] The elastic member is a wave plate or a spring.

[0021] The above structure of the present invention can achieve the following beneficial effects:

[0022] When in use, the locking member applies forces to the two nuts respectively, so that the two nuts move in directions away from or towards each other, that is, the locking member causes the two nuts to apply pre-tightening pressures in opposite directions to the screw threads respectively, thereby eliminating the gap between the moving module and the screw threads. When driving, according to the driving direction, the unlocking member applies a driving force in the opposite direction of the force to the nuts in the moving direction of the moving module, so as to offset the pre-tightening pressure in the driving direction, thereby achieving the purpose of unlocking. Even if the pre-tightening force is too large, the transmission efficiency will not be reduced, so that the moving module can easily move in the driving direction.

[0023] By cross-arranging the two moving seats in a scissor shape, the pressure between the moving module and the guide rods can be eliminated when the moving module is driven to move, so that the moving module can slide smoothly on the two guide rods. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the structure of this application;

[0025] Figure 2 It is a structural schematic diagram of some structures in this application;

[0026] Figure 3 A side view of the present application;

[0027] Figure 4 This is a cross-sectional view of the structure of the unlocking screw rod in this application;

[0028] Figure 5 for Figure 4 A schematic diagram of the enlarged structure at point A in the middle.

[0029] In the figure: 1, driving screw; 2, nut; 3, guide rod; 4, moving seat; 41, abutting end face; 42, slide groove; 43, collar; 5, unlocking screw; 6, slider; 7, elastic member. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0031] It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, product or equipment comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0032] The following is combined with Figure 1-Figure 5 This application is described in further detail.

[0033] refer to Figure 1-Figure 3 As shown, a self-unlocking anti-backlash screw drive assembly includes: a drive screw 1, a moving module, a locking member, an unlocking member and a guide member, wherein the guide member is used to guide the movement of the moving module so that the moving module performs translational movement;

[0034] The moving module includes two submodules, each of which includes a nut 2. The two nuts 2 are sleeved on the driving screw 1 and are threadedly connected to the driving screw 1.

[0035] The locking member is used to apply a force along the axial direction of the driving screw rod 1 to the two nuts 2 respectively, and the force of the locking member causes the two nuts 2 to move to the side away from each other;

[0036] The unlocking member is used to apply a driving force opposite to the direction of the applied force to one of the nuts 2 .

[0037] Based on the above structure, when in use, the locking member applies a force to the two nuts 2 respectively, so that the two nuts 2 move in directions away from or towards each other, that is, the locking member causes the two nuts 2 to apply pre-tightening pressures in opposite directions to the threads of the screw rod 1 respectively (acting in different directions of the threads of the screw rod 1 respectively), thereby eliminating the gap between the threads of the moving module and the screw rod 1. When driving, according to the driving direction (relative to the movement direction of the screw rod 1), the unlocking member applies a driving force in the opposite direction of the force to the nut 2 in the movement direction of the moving module, thereby offsetting the pre-tightening pressure in the driving direction, thereby achieving the purpose of unlocking. Even if the pre-tightening force is too large, the transmission efficiency will not be reduced, so that the moving module can easily move in the driving direction.

[0038] like Figure 1 and Figure 2 As shown, in order to guide and limit the movement of the mobile module, the guide member includes two guide rods 3, and the two ends of the mobile module are respectively mounted on the two guide rods 3. The axial direction of the guide rod 3 is consistent with the axial direction of the driving screw 1, so that the mobile module can only move in the axial direction of the guide rod 3.

[0039] like Figure 1-Figure 3 As shown, the submodule specifically also includes a moving seat 4, a nut 2 is arranged on the moving seat 4, and the two ends of the moving seat 4 extend to the bottom and the top of the two guide rods 3 respectively. The two moving seats 4 are cross-arranged in a scissor shape. The advantage of such an arrangement is that the pressure between the moving module and the guide rod 3 can be eliminated, so that the moving module can slide smoothly on the two guide rods 3. Specifically, when the moving module is relatively stationary with the driving screw 1, the locking member causes the two nuts 2 to move to the side away from each other, thereby causing the two nuts 2 to have reverse torques, so that the two ends of the two moving seats 4 Apply pressure to the two guide rods 3 respectively so that the gap between the moving seat 4 and the guide rod 3 is also eliminated (locked). When driving, a driving force opposite to the direction of the force is applied to the nut 2 in the moving direction of the moving module through the unlocking member, so that the nut 2 moves to one side of the other nut 2, so that the pressure between the two ends of the moving seat 3 corresponding to the nut 2 on the guide rod 3 is reduced, and the pressure applied to the guide rod 3 by the two ends of the other moving seat 4 due to the rotation of the driving screw 1 is also reduced, so that the friction between the moving module and the guide rod 3 is reduced, ensuring that the moving module moves more smoothly.

[0040] Further optimization is that grooves are provided on both ends of the movable seat 4 near the two guide rods 3, so that it is clamped on the ring side of the corresponding guide rod 3 through the groove, and a gasket is provided between the guide rod 3 and the movable seat 4.

[0041] like Figure 2, Figure 4 and Figure 5 As shown, the unlocking member specifically includes an unlocking screw rod 5 and a slider 6. The slider 6 is slidably arranged between the two moving seats 4. The unlocking screw rod 5 passes through the slider 6 and is threadedly connected to the slider 6. The unlocking screw rod 5 rotates to make the slider 6 move along the axial direction of the unlocking screw rod 5. The unlocking screw rod 5 is consistent with the axial direction of the driving screw rod 1; the two moving seats 4 are both provided with interference end faces 41, and the two interference end faces 41 are respectively arranged on both sides of the movement direction of the slider 6. By rotating the unlocking screw rod 5, the slider 6 slides to one side and interferes with one of the interference end faces 41, so that the moving seat 4 corresponding to the interference end face 41 moves, thereby realizing unlocking and eliminating the locking force. In order to better achieve the unlocking effect, the transmission ratio of the unlocking screw rod 5 is smaller than the transmission ratio of the driving screw rod 1.

[0042] Among them, Figure 4 and Figure 5 As shown, the specific installation structure of the slider 6 can be: a slide groove 42 is set on the side where the moving seat 4 is close to each other, and the two ends of the slider 6 are respectively slidably set in the slide groove 42, and the two slide grooves 42 are axially staggered with each other on the unlocking screw rod 5. The side where the two slide grooves 42 are away from each other is the abutment end face 41, and the movement of the slider 6 is limited by the two slide grooves 42, so that the slider 6 makes a translational motion.

[0043] As a further optimization, each movable seat 4 is provided with a collar 43 , which is sleeved on the ring side of the unlocking screw rod 5 , and the two movable seats 4 are sleeved on the unlocking screw rod 5 through the collar 43 respectively, so that the unlocking screw rod 5 is installed and limited.

[0044] like Figure 2 and Figure 3 As shown, in order to provide a force to the two nuts 2, the locking member can be an elastic member 7, and the elastic member 7 is arranged between the two nuts 2. In this way, the elastic force of the elastic member 7 serves as a force to push the two nuts 2, so that the two nuts 2 move in opposite directions. The elastic member 7 can use a wave plate or a spring according to actual usage.

[0045] The working principle of the present invention is as follows: when in use, the locking member applies a force to the two nuts 2 respectively, so that the two nuts 2 move in directions away from or towards each other, that is, the locking member causes the two nuts 2 to apply pre-tightening pressures in opposite directions to the threads of the screw rod 1 respectively, thereby eliminating the gap between the threads of the moving module and the screw rod 1. When driving, according to the driving direction, the unlocking member applies a driving force in the opposite direction of the force to the nuts 2 in the moving direction of the moving module, so as to offset the pre-tightening pressure in the driving direction, thereby achieving the purpose of unlocking. Even if the pre-tightening force is too large, the transmission efficiency will not be reduced, so that the moving module can easily move in the driving direction.

[0046] The above are only preferred embodiments of the present application, and the present invention is not limited to the above embodiments. It is understood that other improvements and changes directly derived or associated by those skilled in the art without departing from the spirit and concept of the present invention should be considered to be included in the protection scope of the present invention.

Claims

1. A self-unlocking anti-backlash screw drive assembly, characterized in that: include: A driving screw (1), a moving module, a locking member, an unlocking member and a guide member, wherein the guide member is used to guide the movement of the moving module so that the moving module performs translational movement; The moving module comprises two submodules, each of which comprises a nut (2), and the two nuts (2) are both sleeved on the driving screw (1) and threadedly connected to the driving screw (1); The locking member is used to apply a force along the axial direction of the driving screw rod (1) to the two nuts (2) respectively, and the force of the locking member causes the two nuts (2) to move to a side away from each other; The unlocking member is used to apply a driving force opposite to the direction of the acting force to one of the nuts (2).

2. A self-unlocking anti-backlash screw drive assembly according to claim 1, characterized in that: The guide member comprises two guide rods (3), and the two ends of the moving module are respectively sleeved on the two guide rods (3), and the axial direction of the guide rod (3) is consistent with the axial direction of the driving screw rod (1).

3. A self-unlocking anti-backlash screw drive assembly according to claim 2, characterized in that: The submodule further comprises a movable seat (4), the nut (2) being arranged on the movable seat (4), the two ends of the movable seat (4) respectively extending to the bottom and the top of the two guide rods (3), and the two movable seats (4) being arranged crosswise in a scissor shape.

4. A self-unlocking anti-backlash screw drive assembly according to claim 3, characterized in that: Grooves are provided on one side of both ends of the movable seat (4) close to the two guide rods (3).

5. A self-unlocking anti-backlash screw drive assembly according to claim 3, characterized in that: The unlocking member comprises an unlocking screw rod (5) and a slider (6), wherein the slider (6) is slidably arranged between the two movable seats (4), the unlocking screw rod (5) passes through the slider (6) and is threadedly connected to the slider (6), and the unlocking screw rod (5) rotates to make the slider (6) move along the axial direction of the unlocking screw rod (5), and the axial direction of the unlocking screw rod (5) is consistent with that of the driving screw rod (1); The two movable seats (4) are both provided with a contact end surface (41), and the two contact end surfaces (41) are respectively arranged on both sides of the moving direction of the slider (6).

6. A self-unlocking anti-backlash screw drive assembly according to claim 5, characterized in that: The sides of the movable seats (4) that are close to each other are each provided with a slide groove (42), and the two ends of the slider (6) are respectively slidably arranged in the slide groove (42), the two slide grooves (42) are axially staggeredly arranged on the unlocking screw rod (5), and the sides of the two slide grooves (42) that are away from each other are the abutting end faces (41).

7. A self-unlocking anti-backlash screw drive assembly according to claim 5, characterized in that: The movable seat (4) is provided with a sleeve ring (43), and the sleeve ring (43) is sleeved on the ring side of the unlocking screw rod (5).

8. The self-unlocking anti-backlash screw drive assembly according to claim 5, characterized in that: The transmission ratio of the unlocking screw rod (5) is smaller than the transmission ratio of the driving screw rod (1).

9. The self-unlocking anti-backlash screw drive assembly according to claim 1, characterized in that: The locking member is an elastic member (7), and the elastic member (7) is arranged between the two nuts (2).

10. A self-unlocking anti-backlash screw drive assembly according to claim 9, characterized in that: The elastic member (7) is a wave plate or a spring.

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