Single-drive macro-micro mechanism based on screw drive and flexible mechanism

Abstract

The invention relates to a single-drive macro-micro mechanism based on screw drive and a flexible mechanism, belongs to the technical field of precision displacement, and solves the technical problems that in the prior art, a macro-micro two-stage adjusting mechanism is multiple in drive device, complex in structure and high in manufacturing cost. The device comprises a stepping motor, a base, a linear bearing, a through hole cylinder, a circular ring electromagnet, a wedge-shaped ring, a movable circular ring, an inner nut, a connecting piece, a circular plug, an inserting piece, a baffle, a screw, a lead screw and a micro-motion flexible mechanism. The lead screw is driven by the stepping motor to rotate, and rotary motion is converted into linear motion of the inner nut by means of threaded fit of the lead screw and the inner nut, so that macro-motion adjustment is formed. The movable circular ring is attracted by the electromagnet to clamp the through hole cylinder and the base, the through hole cylinder and the base are relatively fixed, displacement input of the flexible mechanism is achieved through movement of the inner nut, and therefore micro displacement is output, and micro adjustment is achieved. According to the mechanism, macro-motion large-stroke adjustment and micro-motion high-precision adjustment can be achieved through single drive.

Description

Technical Field

[0001] The invention belongs to the technical field of precision displacement, and in particular relates to a single-drive macro-micro mechanism based on screw transmission and a flexible mechanism. Background Art

[0002] With the rapid development of science and technology, the application of robotics in the fields of industry, medicine, service and research is becoming more and more extensive. In order to meet the needs of high-precision macro-micro adjustment of robotic systems, higher requirements are put forward for the design of mechanisms with precise positioning and micro-manipulation requirements. The present invention mainly focuses on solving the problems of complex drive system, limited size and difficult to balance adjustment accuracy in traditional micro-adjustment mechanisms.

[0003] At present, in the macro-micro two-stage drive technology, most of them use a combination of multiple drive methods. Macro drives are mostly based on linear motors, and micro drives include piezoelectric drives and magnetostrictors. However, this patent uses a stepper motor to drive the lead screw to rotate, uses the axial movement of the nut to achieve macro displacement, and drives a micro-flexible mechanism with a displacement reduction function to achieve micro displacement. This means that the stepper motor drives the lead screw displacement in both macro and micro drive methods, forming a two-stage adjustment single drive structure. Under the joint adjustment of the stepper motor and the flexible mechanism, a large stroke and high-precision displacement can be achieved. Summary of the invention

[0004] The purpose of the present invention is to provide a macro-micro two-stage precision adjustment mechanism to solve the technical problems of the macro-micro two-stage adjustment mechanism in the prior art having multiple driving devices, complex structure and high manufacturing cost.

[0005] The invention discloses a macro-micro two-stage precision adjustment mechanism, which comprises a stepping motor, a base, a linear bearing, a through-hole cylinder, a circular ring electromagnet, a wedge ring, a movable circular ring, an inner nut, a connecting piece, a circular plug, a plug-in, a baffle, a screw, a lead screw and a micro-motion flexible mechanism.

[0006] The flexible mechanism comprises a displacement output surface, a displacement input surface and a fixed support foot;

[0007] The screw is a cylindrical head hexagon socket screw; a through hole is dug in the middle of the lower part of the inner nut to form a flexible joint with the outer arc;

[0008] The various parts of the mechanism are matched in that the stepper motor is fixed by screws at the lower end of the base, and the through-hole cylinder and other parts are placed on the inner side of the base; the lead screw is connected to the stepper motor by a form connection, and is threadedly connected to the inner nut, the upper end of the inner nut is connected to the flexible mechanism by a plug-in, the through-hole cylinder is connected to the base by a connecting piece to form a moving pair, and the through-hole cylinder is connected to the flexible mechanism by a screw, so that the inner nut cannot rotate, and when the lead screw rotates, the inner nut moves up and down; the inner side of the through-hole cylinder is interference-fitted with the outer side of the linear bearing and clearance-fitted with the lead screw, the through-hole cylinder is nested with the wedge ring, the inner ring of the moving ring is nested with the outer ring of the wedge ring, the upper end of the ring electromagnet is in contact with the lower end of the wedge ring, and the baffle is fixed to the lower end of the through-hole cylinder by screws;

[0009] The working principle of the mechanism is divided into macro-motion and micro-motion; when the annular electromagnet is not energized, the whole body moves macro-motion, the inner nut forms a positive connection with the flexible mechanism through the plug-in, the flexible mechanism is connected to the through-hole cylinder through screws, and the through-hole cylinder forms an up and down moving pair with the base through the connecting piece. The inherent connection prevents the through-hole cylinder and the inner nut from relative rotation, and at the same time, the rotation of the lead screw drives the inner nut to move up and down, thereby driving the overall up and down movement; when the annular electromagnet is energized, the electromagnet absorbs the moving ring, and the moving ring descends and clamps the through-hole cylinder and the base at the same time. At this time, the through-hole cylinder and the base no longer produce relative displacement, and the rotation of the lead screw drives the inner nut to move upward, so that the flexible mechanism obtains displacement input, the flexible mechanism is deformed, and the displacement output end of the flexible mechanism produces a small displacement output, that is, micro-motion.

[0010] The beneficial technical effects of the present invention are as follows: the stepping motor converts rotational motion into linear motion through the threaded fit between the lead screw and the inner nut, so that the mechanism is displaced in the axial direction; the clamping fixation in the device is achieved by controlling the switch of the electromagnet, so that the mechanism can complete macro displacement and micro displacement respectively; the rebound problem existing in the threaded fit is compensated by the rebound of the flexible joint in the inner nut after compression and deformation; under the action of such a single-drive two-stage adjustment mechanism, large-stroke adjustment of macro movement and precise adjustment of micro movement are achieved, the structure and control are simple, and the manufacturing and use costs are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a structural diagram of the outer contour of a single-drive macro-micro mechanism based on a spiral transmission and a flexible mechanism of the present invention;

[0012] Figure 2 This is an internal structure diagram of a single-drive macro-micro mechanism based on a spiral transmission and a flexible mechanism of the present invention;

[0013] Figure 3 This is a cross-sectional view of a single-drive macro-micro mechanism based on a spiral transmission and a flexible mechanism of the present invention;

[0014] Figure 4 This is an outline diagram of a single-drive macro-micro mechanism flexible mechanism based on a spiral transmission and a flexible mechanism of the present invention;

[0015] Figure 5 This is a cross-sectional view of a through-hole cylinder of a single-drive macro-micro mechanism based on a spiral transmission and a flexible mechanism of the present invention;

[0016] Figure 6 This is a cross-sectional view of a single-drive macro-micro mechanism base based on a spiral transmission and a flexible mechanism of the present invention;

[0017] Figure 7 This is a structural diagram of a single-drive macro-micro mechanism lead screw based on a spiral transmission and a flexible mechanism of the present invention;

[0018] Figure 8 This is a structural diagram of a single-drive macro-micro mechanism linear bearing based on a spiral transmission and a flexible mechanism of the present invention;

[0019] Fig. 9 This is a structural diagram of a nut inside a single-drive macro-micro mechanism based on spiral transmission and flexible mechanism of the present invention. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the accompanying drawings.

[0021] See attached Figure 1 , Attachment Figure 2 , Attachment Figure 3 , Attachment Figure 4 , Attachment Figure 5 , Attachment Figure 6 , Attachment Figure 7 and attached Figure 8 The present invention discloses a single-drive macro-micro mechanism based on spiral transmission and flexible mechanism, comprising a stepping motor 14, a linear bearing 3, a base 1, a through-hole cylinder 4, a circular ring electromagnet 12, a wedge ring 10, a moving circular ring 11, an inner nut 9, a connecting piece 6, a circular plug 7, a plug-in 8, a baffle 13, a screw 5, a lead screw 15 and a micro-flexible mechanism 2;

[0022] like Figure 4 As shown, the flexible mechanism includes a displacement output surface 2001, a displacement input surface 2003 and a fixed support foot 2002;

[0023] like Figure 3As shown, the stepper motor 14 is fixed to the lower end of the base 1 by screws 5, and the through-hole cylinder 4 and other components are placed inside the base 1; the lead screw 15 is connected to the stepper motor 14 by a form-fitting connection, and is threadedly connected to the inner nut 9, and the upper end of the inner nut 9 is connected to the flexible mechanism 2 by a plug-in 8, and the through-hole cylinder 4 is connected to the base 1 by a connecting piece 6 to form a moving pair, and the through-hole cylinder 4 is connected to the flexible mechanism 2 by screws 5, so that the inner nut 9 cannot rotate, and when the lead screw 15 rotates, the inner nut 9 moves up and down;

[0024] like Figure 2 As shown, the inner side 4004 of the through-hole cylinder 4 is interference-fitted with the outer side 3002 of the linear bearing 3, the outer side of the through-hole cylinder 4 is gap-fitted with the inner ring of the wedge ring 10, the outer ring of the wedge ring 10 is gap-fitted with the inner ring of the moving ring 11, and the outer ring of the moving ring 11 is gap-fitted with the inner wall 1001 of the base 1; the upper end of the annular electromagnet 12 is in contact with the lower end of the wedge ring 10, and the lower end of the annular electromagnet 12 is in contact with the baffle 13, and the baffle 13 is fixed to the lower end 4005 of the through-hole cylinder 4 by means of screws 5;

[0025] The specific implementation scheme of the present invention is divided into macro-motion and micro-motion; when the circular electromagnet 12 is not energized, the whole macro-motion, the inner nut 9 is connected with the flexible mechanism 2 through the plug-in 8, the flexible mechanism 2 is connected with the through-hole cylinder 4 through the screw 5, and the through-hole cylinder 4 forms a moving pair with the base 1 through the connecting piece 6. The inherent connection prevents the through-hole cylinder 4 and the inner nut 9 from rotating relative to each other. The lead screw 15 rotates to drive the inner nut 9 to move up and down, thereby driving the structure including the flexible mechanism to move up and down; when the circular electromagnet 12 is energized, the electromagnet 12 absorbs the moving ring 11, and the moving ring 11 descends, clamping the through-hole The cylinder 4 and the base 1, at this time, the through-hole cylinder 4 and the base 1 no longer produce relative displacement, and the lead screw 15 rotates, driving the inner nut 9 to move up and down, forming a displacement input to the flexible mechanism 2, and the displacement input surface 2003 of the flexible mechanism 2 moves upward, and the flexible mechanism 2 is deformed, so that the displacement output surface 2001 of the flexible mechanism position outputs a small displacement, and the micro-motion of the device is realized; after the circular electromagnet 12 is powered off, the moving circular ring 11 and the wedge ring 10 no longer clamp the through-hole cylinder 4 and the base 1, and the rotation of the lead screw 15 only causes the inner nut 9 to move up and down, that is, the device can be macro-positioned again. Under the action of such a single-drive two-stage adjustment mechanism, large-stroke adjustment of macro-motion and precise adjustment of micro-motion are realized, the structure and control are simple, and the manufacturing and use costs are reduced.

Claims

1. A single-drive macro-micro mechanism based on screw transmission and flexible mechanism, characterized in that: It comprises a stepping motor (14), a linear bearing (3), a base (1), a through-hole cylinder (4), a circular ring electromagnet (12), a wedge ring (10), a movable circular ring (11), an inner nut (9), a connecting piece (6), a circular plug (7), a plug-in unit (8), a baffle (13), a screw (5), a lead screw (15) and a micro-motion flexible mechanism (2); The base (1) is a fixing device for the entire structure. The stepper motor (14) is mounted on the bottom end (1002) of the base (1) by means of screws (5), and the remaining components are placed on the inner side (1001) of the base (1). The lead screw (15) is connected to the stepper motor (14) by a form-fit connection and is connected to the inner nut (9) by a threaded connection; the inner nut (9) is in contact with the ball on the inner side (3001) of the linear bearing (3) and can move axially in the linear bearing (3); the outer side (3002) of the linear bearing is interference-fitted with the inner side (4004) of the through-hole cylinder (4); the outer side (4003) of the through-hole cylinder (4) is clearance-fitted with the inner ring of the wedge ring (10); the outer ring of the wedge ring (10) is clearance-fitted with the moving The inner ring of the circular ring (11) is clearance-matched, and the outer ring of the movable circular ring (11) is clearance-matched with the inner side of the base (1); the lower end of the wedge ring (10) contacts the upper end of the circular ring electromagnet (12), the outer hole (4002) of the upper part of the through-hole cylinder (4) is interference-fitted with one end of the connecting piece (6), and the other end of the connecting piece (6) is clearance-matched with the base (1), forming a moving pair, and the baffle (13) is fixed to the lower end (4005) of the through-hole cylinder (4) by screws (5); The two fixed feet (2002) of the micro-motion flexible mechanism (2) are fixed to the upper end (4001) of the through-hole cylinder (4) by means of screws (5), and the intermediate displacement input part (2003) is in direct contact with the upper end of the inner nut (9) and is connected via a plug-in (8).

2. A single-drive macro-micro mechanism based on a screw transmission and a flexible mechanism according to claim 1, characterized in that: A single drive is used to simultaneously realize macro displacement and micro displacement; the rotation shaft of the stepping motor (14) drives the lead screw (15) and the inner nut (9) to rotate relative to each other; the inner nut (9) is connected to the flexible mechanism (2) through a plug-in unit (8); the flexible mechanism (2) is connected to the upper end (4001) of the through-hole cylinder (4) through screws; the outer side (4002) of the upper part of the through-hole cylinder (4) is interference-fitted with a connecting piece (6); the connecting piece (6) and the base (1) form a moving pair that moves up and down; the inherent connection prevents the through-hole cylinder (4) and the inner nut (9) from rotating relative to each other, that is, the stepping motor (14) drives the lead screw (15) to rotate so that the inner nut (9) can only move upward. The circular electromagnet (12) is energized to generate suction force on the movable circular ring (11), and the movable circular ring (11) moves downward, generating a clamping force on the wedge ring (10) inward, and the wedge ring (10) clamps the through-hole cylinder (4) and clamps the base (1) outward, so that the through-hole cylinder (4) and the base (1) no longer generate relative displacement, and the rotation of the lead screw (15) drives the inner nut (9) to move up and down, and the inner nut (9) and the through-hole cylinder (4) generate relative displacement, thereby generating input displacement on the flexible mechanism (2), the flexible mechanism (2) is deformed, and the output end (2002) generates microscopic displacement.

3. A single-drive macro-micro mechanism based on a screw transmission and a flexible mechanism according to claim 1, characterized in that: The inner nut part, the outer ring (9001) is the outer surface of the nut, which contacts the inner side of the linear bearing (3); the lower end through hole part (9002) and the lower end arc part (9003) form a straight circular flexible hinge, and a gap (9004) is left in the middle of the through hole part; after tightening, it is threadedly connected with the lead screw (15), and the rebound force formed compensates for the backlash problem of the thread.

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