Variant conversion mechanism combining rotary motion and linear motion

Abstract

The invention discloses a variant conversion mechanism combining rotational motion and linear motion, which relates to the technical field of motion conversion structures and comprises a machine body, a lead screw, a movable sliding block, two lead screw nuts, a limiting column, a first driving device, a positioning column and a second driving device. The machine body is provided with a first guide part extending in the first linear direction and a second guide part extending in the circumferential direction. The lead screw is rotatably supported on the machine body through a bearing; the movable sliding block is arranged on the lead screw in a sleeving mode in the mode that the movable sliding block can rotate around the axis of the lead screw, and the movable sliding block is used for being connected with an external assembly. The two lead screw nuts are arranged on the lead screw in a sleeving mode and located on the two sides of the movable sliding block respectively. The limiting column is fixedly connected with the lead screw nut, and the first driving device is in transmission connection with the lead screw; the positioning column is arranged near the second guide part; a positioning hole matched with the positioning column is formed in the movable sliding block; the second driving device is connected with the positioning column through a transmission assembly so as to drive the movable sliding block to rotate. And miniaturization and light weight are easy to realize.

Description

Technical Field

[0001] This invention relates to the field of motion conversion structure technology, and in particular to a variant conversion mechanism that combines rotational motion and linear motion. Background Technology

[0002] The transformation mechanism combining rotary / linear motion and rotary / linear motion is extremely complex, involving not only translation of external components along the fuselage axis but also rotation of external components along the fuselage axis. Previously, such transformation mechanisms were limited by the imperfections of older electronic transmission devices and other hardware. To ensure precise control of these functions, numerous mechanical structures (such as cranks, rockers, and planetary gears) were required. However, the use of numerous complex mechanical structures also presents several problems. Firstly, there is a conflict between structural complexity and reliability. Overly complex structures increase the overall size and weight of the machine, requiring greater force for normal operation and making it more susceptible to wear and tear, leading to malfunctions. Secondly, there is a conflict between energy consumption and efficiency. Numerous complex mechanical structures require a continuous energy supply during transformation and generate significant frictional losses. As mentioned above, the complex structure of the conventional rotary motion / linear motion combination conversion mechanism results in a large overall size and weight, and complicated control. It is not only difficult to achieve the requirements of miniaturization and lightweighting, but also has many problems in the field of medium and large machinery. Summary of the Invention

[0003] The purpose of this invention is to provide a variant conversion mechanism that combines rotational and linear motion to solve the problems existing in the prior art, and to facilitate miniaturization and weight reduction.

[0004] To achieve the above objectives, the present invention provides the following solution:

[0005] The present invention provides a variant conversion mechanism combining rotational and linear motion, comprising: a body, a lead screw, a movable slider, two lead screw nuts, a limit post, a first drive device, a positioning post, and a second drive device.

[0006] The machine body has a first guide portion extending along a first straight line and a second guide portion extending along a circumferential direction, which are connected to each other. A lead screw is rotatably supported on the machine body via bearings, and its axis is parallel to the first straight line. A movable slider is sleeved on the lead screw in a manner that allows it to rotate around the axis of the lead screw, and slides with the first and second guide portions, enabling the movable slider to selectively move linearly along the first guide portion or circumferentially along the second guide portion. The movable slider is used to connect with external components. Two lead screw nuts are sleeved on the lead screw and are located on both sides of the movable slider. Limiting posts and... The lead screw and nut are fixedly connected, and at least part of the limiting post is fixedly set between the two lead screw and nuts; the movable slider is located on the path of the limiting post rotating around the axis of the lead screw; the first driving device is connected to the lead screw transmission and is used to drive the lead screw to rotate; the positioning post is located near the second guide part and its length direction is parallel to the first straight line direction; the movable slider is provided with a positioning hole adapted to the positioning post, and when the movable slider moves to the position corresponding to the second guide part, the positioning post can be inserted into the positioning hole; the second driving device is connected to the positioning post through a transmission component and is used to drive the positioning post to rotate around the axis of the lead screw, thereby driving the movable slider to rotate.

[0007] Preferably, the first guide portion is a linear guide rail formed on the body, and the second guide portion is an arc-shaped guide rail formed on the body.

[0008] Preferably, the movable slider is slidably engaged with the first guide portion and the second guide portion via rolling bearings.

[0009] Preferably, the first driving device is a stepper motor, which is connected to the lead screw via a coupling.

[0010] Preferably, the second drive device is a servo motor, whose output shaft is connected to the positioning column via a servo disc.

[0011] Preferably, the lead screw is supported on the machine body by bearings.

[0012] Preferably, the body is a hollow cylindrical structure with an internal cavity, in which the lead screw, movable slider, lead screw nut, limiting post, first driving device, positioning post and second driving device are all disposed. The side wall of the body is provided with a groove penetrating the side wall, and the groove is the linear guide rail and the arc guide rail.

[0013] Preferably, the number of the first guide portion and the second guide portion is at least one, and the movable slider is provided with a connection structure corresponding to the number of the first guide portions for connecting one or more external components.

[0014] Preferably, the device further includes a lead screw mounting plate, which is disposed within the machine body perpendicular to the axis of the lead screw. The lead screw is mounted on the lead screw mounting plate via bearings. The stepper motor is fixed to the lead screw mounting plate and is connected to the lead screw via a coupling. The second drive device is located on the side of the lead screw mounting plate opposite to the movable slider. The lead screw mounting plate has an arc-shaped hole extending through it along the thickness direction, and the limiting post passes through the arc-shaped hole.

[0015] The present invention achieves the following technical effects compared to the prior art:

[0016] This invention abandons the complex crank-rocker and planetary gear train mechanisms of traditional systems, adopting a direct-drive system with a lead screw and nut and a limit column for motion conversion. This significantly reduces the number of parts and mechanical connection points, thereby lowering the failure rate and improving overall reliability. The simplified mechanical structure also directly avoids system failures caused by wear and tear from complex mechanisms. Furthermore, due to the greatly simplified structure and the elimination of numerous redundant components, the overall size and weight of the mechanism are significantly reduced, solving the pain point of traditional mechanisms being difficult to miniaturize and lighten. This makes it particularly suitable for applications with strict weight and space requirements. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of the structure of the variant conversion mechanism combining rotational and linear motion provided in an embodiment of the present invention;

[0019] Figure 2 for Figure 1 The diagram below shows the structure after removing the remaining structure at the rear of the fuselage.

[0020] Figure 3 Exploded view of the connecting part, rolling bearing and movable slider;

[0021] Figure 4 for Figure 2 Partial structural diagram;

[0022] Figure 5 This is a schematic diagram of the connection between the stepper motor and the lead screw;

[0023] Figure 6 This is a schematic diagram of the structure in which the rolling bearing is fitted to the machine body;

[0024] In the diagram: 1-Stepper motor; 2-Coupling; 3-Horizontal bearing; 4-Lead screw; 5-Double-through copper column; 6-Motor mounting plate; 7-Movable slider; 8-Rolling bearing; 9-Connecting part; 10-Positioning column; 11-Lead screw mounting plate; 12-Servo motor; 13-Tail baffle; 14-Support column; 15-Servo disc; 16-Lead screw nut limit plate; 17-Lead screw nut; 18-Limiting column; 19-Fuse; 20-Linear guide rail; 21-Arc guide rail. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] The following is combined with Figures 1 to 6 The following describes embodiments of the present invention.

[0028] The present invention provides a variant conversion mechanism combining rotational and linear motion, comprising: a body 19, a lead screw 4, a movable slider 7, two lead screw nuts 17, a limiting post 18, a first driving device, a positioning post 10, and a second driving device.

[0029] The machine body 19 is provided with a first guide portion extending along a first straight line and a second guide portion extending along a circumferential direction, the first guide portion and the second guide portion being connected to each other; the lead screw 4 is rotatably supported on the machine body 19 by bearings, and its axis is parallel to the first straight line direction; the movable slider 7 is sleeved on the lead screw 4 in a manner that allows it to rotate around the axis of the lead screw 4, and slides with the first guide portion and the second guide portion, so that the movable slider 7 can selectively move linearly along the first guide portion or circumferentially along the second guide portion, and the movable slider 7 is used to connect with external components; two lead screw nuts 17 are sleeved on the lead screw 4 and are respectively located on both sides of the movable slider 7; the limiting post 18 is connected to the lead screw nut The female nut 17 is fixedly connected, and at least part of the limiting post 18 is fixedly set between the two lead screw nuts 17; the movable slider 7 is located on the path of the limiting post 18 rotating around the axis of the lead screw 4; the first driving device is connected to the lead screw 4 for driving the lead screw 4 to rotate; the positioning post 10 is located near the second guide part, and its length direction is parallel to the first straight line direction; the movable slider 7 is provided with a positioning hole adapted to the positioning post 10, and when the movable slider 7 moves to the position corresponding to the second guide part, the positioning post 10 can be inserted into the positioning hole; the second driving device is connected to the positioning post 10 through a transmission component for driving the positioning post 10 to rotate around the axis of the lead screw 4, thereby driving the movable slider 7 to rotate.

[0030] Usage principle and method:

[0031] The working process of this variant conversion mechanism, which combines rotational and linear motion, is divided into two main stages: the linear translation stage and the rotation stage.

[0032] Linear translation stage:

[0033] Start-up: The first drive device (such as stepper motor 1) is started, driving the lead screw 4 to rotate around its own axis.

[0034] Drive: Since the two lead screw nuts 17 are fixedly connected as a whole by the limiting post 18 and separated from the movable slider 7, initially, the lead screw nuts 17 tend to rotate under the action of friction, but then the movement trajectory of the limiting post 18 is blocked by the movable slider 7, which restricts the rotation of the two lead screw nuts 17.

[0035] Transmission: After the lead screw nut 17 can no longer rotate, it converts the rotational motion of the lead screw 4 into its own linear motion, thereby pushing the movable slider 7 between the two to move along the axis of the lead screw 4.

[0036] Guiding: During this process, the sliding part (rolling bearing 8 in the following embodiment) on the movable slider 7 is constrained in the first guide part (linear guide rail 20 in the following embodiment) of the body 19, ensuring that the movable slider 7 only performs precise linear translation and drives the external components connected to it to move synchronously in a linear motion.

[0037] Rotation phase:

[0038] Positioning: When the movable slider 7 is pushed to the end of its stroke, that is, when it reaches the position to connect with the second guide (the arc-shaped guide rail 21 in the following embodiment), the positioning hole on the movable slider 7 is exactly aligned with the fixed positioning post 10.

[0039] Switching: The positioning pin 10 is inserted into the positioning hole, which locks the circumferential degree of freedom between the movable slider 7 and the positioning pin 10.

[0040] Drive rotation: The second drive device (such as servo motor 12) is activated, and drives the positioning column 10 to rotate around the axis of the lead screw 4 through the transmission assembly (such as servo disk 15).

[0041] Guided rotation: Since the positioning pin 10 has been inserted into the positioning hole of the movable slider 7, it drives the movable slider 7 to rotate synchronously. The sliding part of the movable slider 7 transitions from the first guide part and is constrained in the second guide part (arc guide rail 21), guiding the movable slider 7 and its connected external components to rotate along a precise circumferential trajectory, thereby realizing rotational displacement.

[0042] Reset: When a reset is required, the second drive device first drives the movable slider 7 to rotate to the connection position of the first guide and the second guide. Then, the first drive device rotates the lead screw 4 in the opposite direction, and pulls the movable slider 7 back through the lead screw nut 17 and the limit post 18, and restarts the linear motion.

[0043] Through the above methods, the mechanism realizes two basic motion modes and their conversion: "motor drives lead screw 4 → linear translation" and "after reaching the position, servo motor 12 drives positioning column 10 → precise rotation", which meets the needs of composite variants of external components.

[0044] Therefore, this invention abandons the complex traditional mechanisms such as crank-rocker and planetary gear trains, and adopts a scheme in which the lead screw nut 17 directly drives the mechanism and the limiting column 18 converts the motion. This significantly reduces the number of parts and mechanical connection points, thereby reducing the failure rate of the mechanism and improving overall reliability. The simplification of the mechanical structure also directly avoids the problem of machine failure caused by the wear of complex mechanisms. Moreover, due to the greatly simplified structure, a large number of redundant components are eliminated, and the size and weight of the entire mechanism can be significantly reduced, solving the pain point of traditional mechanisms being difficult to miniaturize and lighten. It is especially suitable for application scenarios with strict requirements on weight and space.

[0045] In some embodiments, two lead screw nut limiting plates 16 are also included. The two lead screw nut limiting plates 16 are respectively disposed on both sides of the integral structure of the two lead screw nuts 17. The two lead screw nuts 17 are respectively fixedly connected to the two lead screw nut limiting plates 16 by screws. The two lead screw nut limiting plates 16 are then fixedly connected by two limiting posts 18, thereby achieving the purpose of fixing the two lead screw nuts 17 together.

[0046] In some embodiments, the first guide portion is a linear guide rail 20 formed on the fuselage 19, and the second guide portion is an arc-shaped guide rail 21 formed on the fuselage 19.

[0047] In this embodiment, the guide rail is directly machined or formed onto the main body 19, eliminating the need for additional parts, connectors, and adjustment steps for installing independent guide rails, resulting in a more compact and integrated structure. This greatly simplifies the assembly process, reduces precision issues caused by accumulated errors from assembling multiple parts, and achieves a high degree of structural integration and unified design. Furthermore, this reduces the number of parts, correspondingly lowering manufacturing and procurement management costs. Simultaneously, avoiding the use of additional guide rail mounting brackets and other structures also contributes to the overall lightweight design of the machine.

[0048] In some embodiments, the movable slider 7 is slidably engaged with the first guide portion and the second guide portion via rolling bearings 8.

[0049] In this embodiment, by replacing traditional sliding friction with rolling friction, the resistance of the movable slider 7 during movement is fundamentally and significantly reduced. This results in a significant reduction in the output torque required by the drive motors (stepper motor 1 and servo motor 12), which not only reduces energy consumption and improves overall energy efficiency but also makes it possible to use smaller, lighter, and lower-power motors, further promoting the miniaturization and weight reduction of the mechanism. Furthermore, wear between the rolling elements (such as balls) of the bearings and the guide rails is reduced to an extremely low level, greatly delaying the process of decreased accuracy or functional failure due to wear. Its service life far exceeds that of sliding friction mechanisms, exhibiting extremely high reliability and significantly reducing maintenance frequency and total lifecycle costs.

[0050] In some embodiments, the first driving device is a stepper motor 1, which is connected to a lead screw 4 via a coupling 2.

[0051] In this embodiment, the stepper motor 1 can accurately convert electrical pulse signals into angular displacement, achieving precise control of its rotation angle and speed without the need for a complex closed-loop feedback system (such as an encoder). By controlling the number and frequency of input pulses, the rotation angle of the lead screw 4 can be precisely controlled, thereby accurately positioning the movable slider 7 and external components in the linear direction, perfectly meeting the stringent requirements of the variant mechanism for pose repeatability accuracy.

[0052] In some embodiments, the second drive device is a servo motor 12, whose output shaft is connected to the positioning post 10 via a servo disc 15.

[0053] In this embodiment, the servo motor 12 is a servo mechanism that integrates a motor, gear reduction gear, control circuit, and position feedback device (such as a potentiometer). It receives pulse width modulation (PWM) signals and can automatically drive the output shaft to rotate precisely to and maintain the angle specified by the command. This makes the rotational displacement control of external components extremely simple and precise, eliminating the need for complex external angle measurement and closed-loop control systems, and achieving high-performance rotation that is "as commanded, immediately in place".

[0054] In some embodiments, the lead screw 4 is supported on the machine body 19 by bearings.

[0055] In this embodiment, the bearing support provides a stable and precise center of rotation for the lead screw 4. This greatly limits the radial and axial runout and sway of the lead screw 4, ensuring a high degree of stability in its rotational motion. This is the fundamental prerequisite for all subsequent precise transmission (lead screw nut 17 pushing the slider), directly determining the positional accuracy and repeatability of the entire mechanism's linear motion.

[0056] In some embodiments, the body 19 is a hollow cylindrical structure with an internal cavity. The lead screw 4, movable slider 7, lead screw nut 17, limiting post 18, first drive device, positioning post 10 and second drive device are all disposed in the cavity. The side wall of the body 19 is provided with a through groove, which is the linear guide rail 20 and the arc guide rail 21.

[0057] In this embodiment, all transmission, guiding, and actuation components (lead screw 4, movable slider 7, stepper motor 1, servo motor 12, etc.) are encapsulated within a hollow cylindrical housing 19, achieving a high degree of integration. This maximizes space utilization, significantly reduces the overall package size of the mechanism, and achieves an extremely compact layout, making it particularly suitable for use in environments with limited installation space. Furthermore, this design integrates a complex variant conversion mechanism combining rotary and linear motion into a single, fully functional modular unit. During the assembly and debugging of the entire machine, only the entire mechanism module needs to be installed and the wiring harness connected, greatly simplifying the final assembly process and improving production and maintenance efficiency.

[0058] In some embodiments, the number of first guide portions and second guide portions is at least one, and the movable slider 7 is provided with a connection structure corresponding to the number of first guide portions for connecting one or more external components.

[0059] This embodiment, by setting multiple guide parts (such as two symmetrically arranged sets of linear guide rails 20 and arc-shaped guide rails 21) and corresponding connection structures, allows the mechanism to synchronously drive two or more external components to perform completely mirrored or synchronous translational and rotational movements. This solves the problem that a single output mechanism cannot achieve symmetrical and coordinated variations, greatly expanding the application range of the mechanism.

[0060] In some embodiments, a lead screw mounting plate 11 is also included. The lead screw mounting plate 11 is disposed within the machine body 19 perpendicular to the axis of the lead screw 4. The lead screw 4 is mounted on the lead screw mounting plate 11 by bearings. The stepper motor 1 is fixed on the lead screw mounting plate 11 and is connected to the lead screw 4 by a coupling 2. The second drive device is located on the side of the lead screw mounting plate 11 away from the movable slider 7. An arc-shaped hole is opened on the lead screw mounting plate 11 along the thickness direction, and the limiting post 18 passes through the arc-shaped hole.

[0061] In some embodiments, the system also includes a motor mounting plate 6, a tail baffle 13, a support column 14, and a double-through copper column 5. The tail baffle 13 is fixedly connected to the machine body 19. The support column 14 is disposed inside the machine body 19 and is fixedly connected to the tail baffle 13. The support column 14 is also fixedly connected to the lead screw mounting plate 11. The motor mounting plate 6 is disposed between the lead screw mounting plate 11 and the tail baffle 13. A horizontal bearing 3 is disposed on the lead screw mounting plate 11. The motor mounting plate 6 is fixedly connected to the horizontal bearing 3 via the double-through copper column 5. This achieves a fixed connection between the horizontal bearing 3, the motor mounting plate 6, the lead screw mounting plate 11, and the tail baffle 13.

[0062] As shown in the figure, it also includes a connecting part 9, which is inserted into the movable slider 7 and detachably connected by bolts, screws or threaded rods.

[0063] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A variant conversion mechanism combining rotational and linear motion, characterized in that: include: The fuselage has a first guide portion extending along a first straight line direction and a second guide portion extending along a circumferential direction, and the first guide portion and the second guide portion are connected to each other; A lead screw, which is rotatably supported on the machine body by bearings, and whose axis is parallel to the first linear direction; A movable slider is sleeved on the lead screw in a manner that allows it to rotate about the axis of the lead screw, and slides in cooperation with the first guide and the second guide, so that the movable slider can selectively move linearly along the first guide or circumferentially along the second guide. The movable slider is used to connect with external components. Two lead screw nuts are sleeved on the lead screw and located on both sides of the movable slider, respectively; A limiting post is fixedly connected to the lead screw nut, and at least part of the limiting post is fixedly disposed between the two lead screw nuts; the movable slider is located on the path of the limiting post rotating around the lead screw axis; A first driving device is connected to the lead screw drive and is used to drive the lead screw to rotate; A positioning post is disposed near the second guide portion and its length direction is parallel to the first straight line direction; the movable slider is provided with a positioning hole adapted to the positioning post, and when the movable slider moves to the position corresponding to the second guide portion, the positioning post can be inserted into the positioning hole; The second driving device is connected to the positioning column through a transmission component and is used to drive the positioning column to rotate around the axis of the lead screw, thereby driving the movable slider to rotate.

2. The variant conversion mechanism combining rotational and linear motion according to claim 1, characterized in that: The first guide portion is a linear guide rail formed on the body, and the second guide portion is an arc-shaped guide rail formed on the body.

3. The variant conversion mechanism combining rotational and linear motion according to claim 1, characterized in that: The movable slider is slidably engaged with the first guide and the second guide via rolling bearings.

4. The variant conversion mechanism combining rotational and linear motion according to claim 1, characterized in that: The first driving device is a stepper motor, which is connected to the lead screw via a coupling.

5. The variant conversion mechanism combining rotational and linear motion according to claim 1, characterized in that: The second drive device is a servo motor, whose output shaft is connected to the positioning column via a servo disc.

6. The variant conversion mechanism combining rotational and linear motion according to claim 4, characterized in that: The lead screw is supported on the machine body by bearings.

7. The variant conversion mechanism combining rotational and linear motion according to claim 2, characterized in that: The body is a hollow cylindrical structure with an internal cavity. The lead screw, movable slider, lead screw nut, limiting post, first drive device, positioning post and second drive device are all located in the cavity. The side wall of the body is provided with a groove that penetrates the side wall. The groove is the linear guide rail and the arc guide rail.

8. The variant conversion mechanism combining rotational and linear motion according to claim 1, characterized in that: The number of the first guide portion and the second guide portion is at least one, and the movable slider is provided with a connection structure corresponding to the number of the first guide portions for connecting one or more external components.

9. The variant conversion mechanism combining rotational and linear motion according to claim 6, characterized in that: It also includes a lead screw mounting plate, which is set inside the machine body perpendicular to the axis of the lead screw. The lead screw is mounted on the lead screw mounting plate by bearings. The stepper motor is fixed on the lead screw mounting plate and is connected to the lead screw via a coupling. The second drive device is located on the side of the lead screw mounting plate away from the movable slider. The lead screw mounting plate has an arc-shaped hole that runs through the lead screw mounting plate along the thickness direction, and the limiting post passes through the arc-shaped hole.

Images