Adjustable crank rocker mechanism, driving device and phase compensation method

Abstract

The invention relates to the technical field of crank rockers, and discloses an adjustable crank rocker mechanism, a driving device and a phase compensation method. The driving device comprises an adjustable crank rocker mechanism, a servo motor connected with an input shaft of the adjustable crank rocker mechanism to rotate and an executing mechanism connected with an output shaft of the adjustable crank rocker mechanism. The phase compensation method comprises the following steps: acquiring a standard motion curve F corresponding to an expected swinging rule of an output shaft, wherein the standard motion curve F satisfies F = A * cos (2 * pi * time * f) + B; based on the standard motion curve F, reversely calculating a motion curve Fin of the input shaft through a geometric dimension relation; and forming a control signal for controlling the rotation of a rotating shaft of the servo motor based on the motion curve Fin. The swing rule of the rocker of the adjustable crank rocker mechanism is driven to conform to a standard sinusoidal motion curve, and the defects that a traditional crank rocker mechanism is different in reciprocating speed and has the quick-return motion characteristic are overcome.

Description

Technical Field

[0001] This invention relates to the field of crank-rocker technology, and in particular to an adjustable crank-rocker mechanism, a drive device, and a phase compensation method. Background Technology

[0002] The crank-rocker mechanism is a common mechanical system composed of a crank, connecting rod, rocker arm, and other components, and is widely used in various mechanical equipment. The working principle of the crank-rocker mechanism is to convert the continuous rotational motion of the crank into the reciprocating oscillating motion of the rocker arm, and transmit it to the working parts so that they can perform specific functions.

[0003] With the development of precision mechanical instruments and equipment, the requirements for the control of reciprocating oscillations are becoming increasingly stringent. The crank-rocker mechanism, as a reciprocating oscillation generating mechanism, possesses extremely high operational stability and reliability. However, its inherent structural characteristics give it a quick-return motion characteristic, meaning that the speed is inconsistent during the reciprocating oscillation process. This results in the output motion curve of the crank-rocker mechanism being a stretched, deformed quasi-sine curve, which has a certain phase difference from the standard sine curve. Therefore, it cannot achieve precise motion control and is unsuitable for application in precision mechanical instruments and equipment. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention provides an adjustable crank rocker mechanism, a driving device, and a phase compensation method.

[0005] This invention is achieved using the following technical solution: In some embodiments, an adjustable crank-rocker mechanism is provided, including an input shaft, a crank, a connecting rod, a rocker arm, and an output shaft; the input shaft is fixedly connected to the crank, the two ends of the connecting rod are pivotally connected to the crank and the rocker arm respectively, and the output shaft is fixedly connected to the end of the rocker arm away from the connecting rod; wherein the crank includes a crank seat and an adjustment assembly disposed on the crank seat, the adjustment assembly being configured to adjust the swing radius of the crank.

[0006] In some embodiments, the adjusting assembly includes a lead screw shaft and a lead screw sleeve; the lead screw shaft is rotatably disposed on the crank seat, the lead screw sleeve is sleeved on the lead screw shaft and threadedly connected to the lead screw shaft; the crank seat is fixedly connected to the input shaft, and the lead screw sleeve is pivotally connected to the connecting rod.

[0007] In some embodiments, the crank seat has a slide groove, a plurality of positioning holes passing through the slide groove, and a positioning member capable of passing through the positioning holes; the slide groove extends along the length direction of the lead screw shaft, and the plurality of positioning holes are arranged at intervals along the direction of extension of the slide groove; the lead screw sleeve slides in the slide groove; the positioning member passes through the positioning hole corresponding to the position of the lead screw sleeve and abuts against the lead screw sleeve to define the relative position of the lead screw sleeve and the slide groove.

[0008] In some embodiments, the slide is a dovetail groove, and the lead screw sleeve has a dovetail-shaped structural portion adapted to the shape of the dovetail groove, the dovetail-shaped structural portion being slidably attached to the dovetail groove.

[0009] In some embodiments, a drive device is provided, including a servo motor, an actuator, a controller, and the aforementioned adjustable crank-rocker mechanism; the servo motor is configured to drive the input shaft to rotate, the output shaft is configured to drive the actuator to perform an action; and the controller is configured to send control signals to the servo motor.

[0010] In some embodiments, a phase compensation method is provided for controlling the operation of the crank-rocker drive device; the phase compensation method includes the following process: Obtain the standard motion curve F corresponding to the desired oscillation law of the output shaft, wherein the standard motion curve F satisfies F=A*cos(2*π*time*f)+B; based on the standard motion curve F, calculate the motion curve Fin of the input shaft in reverse through the geometric dimensional relationship of the crank-rocker mechanism; and generate a control signal based on the motion curve Fin to control the rotation of the servo motor shaft.

[0011] In some embodiments, the process of obtaining the standard motion curve F corresponding to the desired oscillation law of the output shaft includes: Set the desired swing amplitude X0 and desired swing frequency f of the output shaft; obtain the crank swing radius BM corresponding to the desired swing amplitude X0; adjust the actual crank swing radius of the crank rocker mechanism to the crank swing radius BM; obtain the upper limit angle value X1 and the lower limit angle value X2 of the rocker corresponding to the crank swing radius BM; where A=(X1+X2) / 2, B=(X1-X2) / 2.

[0012] In some embodiments, the process of obtaining the crank swing radius BM corresponding to the desired swing amplitude X0 includes: The crank swing radius BM1 corresponding to the upper limit amplitude of the desired swing amplitude XO is calculated using the geometric dimensions of the crank-rocker mechanism, and the crank swing radius BM2 corresponding to the lower limit amplitude of the desired swing amplitude XO is calculated using the geometric dimensions of the crank-rocker mechanism; BM=(BM1+BM2) / 2.

[0013] In some embodiments, when the joystick is at the upper limit angle value X1, the motion curve F is at the 0 phase reference; when the joystick is at the lower limit angle value X2, the motion curve F is at the π phase reference.

[0014] In some embodiments, the standard motion curve F is reacquired when the desired swing amplitude X0 and / or desired swing frequency f changes.

[0015] The beneficial effects of this application include at least the following: Compared with the prior art, this invention obtains a corresponding standard motion curve F based on the desired oscillation law of the output shaft of the crank-rocker mechanism, calculates the motion curve Fin of the input shaft based on the standard motion curve F, and forms a control signal for controlling the rotation of the servo motor shaft based on the motion curve Fin. Under the control of this control signal, the rotational speed of the servo motor shaft changes periodically, thereby driving the oscillation law of the rocker arm of the adjustable crank-rocker mechanism to conform to a more standard sinusoidal motion curve, overcoming the shortcomings of the traditional crank-rocker mechanism's different reciprocating speeds and quick-return motion characteristics. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the crank-rocker mechanism according to some embodiments of the present invention; Figure 2 This is a schematic cross-sectional view of the output shaft and crank in some embodiments of the present invention; Figure 3 This is a schematic diagram of the crank and connecting rod according to some embodiments of the present invention; Figure 4 This is a cross-sectional structural diagram of the output shaft according to some embodiments of the present invention; Figure 5 This is a schematic diagram of the standard motion curve F in some embodiments of the present invention; Figure 6 This is a geometric dimension diagram of the crank-rocker mechanism in some embodiments of the present invention when it is at the upper limit amplitude position of X0; Figure 7 This is a schematic diagram of the geometric dimensions of the crank-rocker mechanism in some embodiments of the present invention when it is at the lower limit amplitude position of X0; Figure 8 This is a schematic diagram of the motion curve Fin of some embodiments of the present invention; Figure 9 This is one of the geometric dimension schematic diagrams of a crank-rocker mechanism according to some embodiments of the present invention; Figure 10 This is a second geometric dimension schematic diagram of a crank-rocker mechanism according to some embodiments of the present invention; Figure 11 This is the third geometric dimension schematic diagram of a crank-rocker mechanism according to some embodiments of the present invention; Figure 12 This is the fourth geometric dimension schematic diagram of a crank-rocker mechanism according to some embodiments of the present invention.

[0017] The diagram is labeled as follows: 10, input shaft; 11, counterweight wheel; 20, crank; 21, lead screw sleeve; 211, dovetail structure; 22, lead screw shaft; 23, crank seat; 231, slide groove; 232, positioning hole; 24, positioning element; 30, connecting rod; 40, rocker arm; 50, output shaft. Detailed Implementation

[0018] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0019] Please see Figure 1 , Figure 2 and Figure 3 In some embodiments of this application, an adjustable crank-rocker mechanism is provided, including an input shaft 10, a crank 20, a connecting rod 30, a rocker arm 40, and an output shaft 50. The input shaft 10 is fixedly connected to the crank 20, and both ends of the connecting rod 30 are pivotally connected to the crank 20 and the rocker arm 40, respectively. The output shaft 50 is fixedly connected to the end of the rocker arm 40 away from the connecting rod 30. The crank 20 includes a crank seat 23 and an adjustment assembly disposed on the crank seat 23. The adjustment assembly is configured to adjust the swing radius of the crank 20. By adjusting the swing radius of the crank 20, the swing amplitude of the output shaft 50 can be adjusted to adapt to different action output requirements, thereby increasing the applicability range of the adjustable crank-rocker mechanism.

[0020] In some embodiments, the input shaft 10 is connected to the ground or other supporting components via two bearing assemblies. Specifically, each bearing assembly includes a bearing housing and a bearing. The bearing housing is fixed to the ground or other supporting components by fasteners. A vibration isolator, such as a vibration damping pad made of soft material, is provided between the bearing housing and the ground or supporting components to buffer and absorb vibrations. The two bearings are respectively mounted on two bearing housings, and the two ends of the input shaft 10 are respectively mounted on the two bearings. The two bearings provide stable support for the input shaft 10. The input shaft 10 is also fitted with a counterweight wheel 11. The counterweight wheel 11 is located between the two bearings and is connected to the input shaft 10 by a key connection to enable the counterweight wheel 11 and the input shaft 10 to rotate synchronously. In addition, the input shaft 10 is provided with a shoulder and a locking nut. The locking nut is threaded to the input shaft 10, and the counterweight wheel 11 is located between the shoulder and the locking nut. The locking nut and the shoulder restrict the axial movement of the counterweight wheel 11 along the input shaft 10. By using the aforementioned scheme, the relative position of the input shaft 10 and the configuration wheel is defined, and the weight of the counterweight wheel 11 is used to increase the rotational inertia of the input shaft 10, so as to ensure the stability of the rotation of the input shaft 10.

[0021] In some embodiments, the crank seat 23 is fixedly connected to the input shaft 10. Specifically, a insertion hole is provided at the middle position of the back side of the crank seat 23, the end of the input shaft 10 is inserted into the insertion hole, and fasteners are used to connect the end wall of the input shaft 10 and the crank seat 23 so that the two can rotate synchronously.

[0022] In some embodiments, the adjustment assembly includes a lead screw shaft 22 and a lead screw sleeve 21. The lead screw shaft 22 is rotatably mounted on a crank seat 23. Specifically, a lead screw seat is provided on each of the two sides of the front of the crank seat 23 along its length, and both ends of the lead screw shaft 22 are rotatably mounted on the two lead screw seats. The lead screw sleeve 21 is sleeved on the lead screw shaft 22 and threadedly connected to the lead screw shaft 22. The lead screw sleeve 21 is pivotally connected to the connecting rod 30. In some applications, one end of the lead screw shaft 22 is rotated manually or using a tool to rotate the lead screw shaft 22 relative to the lead screw seat, thereby forcing the lead screw sleeve 21 to move axially along the lead screw shaft 22 to change the swing radius of the crank 20. Further, the swing radius of the crank 20 can be understood as the distance between the pivot axis of the lead screw sleeve 21 and the connecting rod 30 and the axis of the input shaft 10.

[0023] In some embodiments, the crank seat 23 is provided with a groove 231, a plurality of positioning holes 232 passing through the groove 231, and positioning members 24 capable of passing through the positioning holes 232. The groove 231 is located on the front side of the crank seat 23 and extends along the length direction of the lead screw shaft 22. The plurality of positioning holes 232 are arranged at intervals along the direction of extension of the groove 231. The lead screw sleeve 21 slides in the groove 231, and the groove 231 can improve the stability of the movement of the lead screw sleeve 21. The positioning element 24 passes through the positioning hole 232 corresponding to the position of the lead screw sleeve 21 and abuts against the lead screw sleeve 21. Specifically, the positioning element 24 can be a screw. The lead screw sleeve 21 has a threaded hole. When the lead screw sleeve 21 slides along the slide groove 231 to the expected position, the threaded hole aligns with one of the multiple positioning holes 232. The screw passes through the positioning hole 232 and is threadedly connected to the threaded hole of the lead screw sleeve 21. The threaded rod, the positioning hole 232 and the threaded hole together limit the relative position of the lead screw sleeve 21 and the slide groove 231 to ensure that the swing radius of the crank 20 is constant when the crank 20 rotates.

[0024] In some embodiments, the slide groove 231 is a dovetail groove, and the lead screw sleeve 21 has a dovetail-shaped structural portion 211 adapted to the shape of the dovetail groove, the dovetail-shaped structural portion 211 slidingly engaging with the dovetail groove. This connection method, on the one hand, defines the relative position of the lead screw sleeve 21 and the slide groove 231 in the radial direction of the lead screw shaft 22, preventing the lead screw sleeve 21 from applying a force to the lead screw shaft 22 in the radial direction, thus preventing the lead screw shaft 22 from bending and reducing the accuracy of the crank 20's swing radius; on the other hand, it improves the stability of the lead screw sleeve 21 when sliding along the slide groove 231.

[0025] In some embodiments, the lead screw sleeve 21 is pivotally connected to the connecting rod 30 via a self-aligning roller bearing, and the connecting rod 30 is pivotally connected to the rocker arm 40 via a self-aligning roller bearing. The self-aligning roller bearing can automatically compensate for the misalignment between the pivot shaft and the self-aligning roller bearing housing during high-frequency, heavy-load operation of the crank-rocker mechanism, ensuring the normal operation of the self-aligning roller bearing and extending its service life.

[0026] Please combine Figure 1 and Figure 4 In some embodiments, the output shaft 50 is connected to the ground or other supporting components via a bearing assembly. Specifically, the bearing assembly includes a bearing housing and a bearing. The bearing housing is fixed to the ground or other supporting components by fasteners. A vibration isolator, such as a vibration damping pad made of soft material, is provided between the bearing housing and the ground or supporting components to buffer and absorb vibrations. The output shaft 50 mates with the bearing.

[0027] In some embodiments, the rocker arm 40 has a mounting hole, and the output shaft 50 is inserted into the mounting hole of the rocker arm 40. The rocker arm 40 is connected to the output shaft 50 by a key connection or a fastener connection so that the two can rotate synchronously.

[0028] In some embodiments, a drive device is provided, including a servo motor, an actuator, a controller, and an adjustable crank-rocker mechanism. The servo motor is configured to drive an input shaft 10 to rotate, and an output shaft 50 is configured to drive the actuator to perform an action. The controller is configured to send control signals to the servo motor to control the servo motor to rotate at a desired output speed and torque. The controller can be a PLC controller, microcomputer, or other controller commonly used in mechanical equipment. Furthermore, the controller has a data storage unit, a data input unit, and a data processing unit. An operator inputs corresponding control data (e.g., program code) through the data input unit (e.g., a keyboard). The data processing unit can read the data stored in the data storage unit and, during the execution of the data, can send corresponding control signals to the servo motor.

[0029] In some embodiments, a phase compensation method is provided for controlling the operation of a crank-rocker 40 drive mechanism. The phase compensation method includes the following processes: S1. Obtain the standard motion curve F corresponding to the desired oscillation law of the output shaft 50, such as... Figure 5 As shown in the figure, the output end can be understood as the output shaft 50 in this embodiment. The standard motion curve F satisfies F=A*cos(2*π*time*f)+B, where the standard motion curve F is a cosine curve, A is the amplitude of the standard motion curve F, B is the bias of the standard motion curve F, time is the time variable, π is the angle, and f is the desired oscillation frequency.

[0030] S2. Based on the standard motion curve F, the motion curve Fin of the input shaft 10 is calculated in reverse using the geometric dimensional relationship of the crank-rocker mechanism.

[0031] S3. Based on the motion curve Fin, a control signal is generated to control the rotation of the servo motor shaft.

[0032] In some embodiments, the process of obtaining the standard motion curve F corresponding to the desired oscillation law of the output shaft 50 in step S1 includes the following steps S11-S15: S11. Set the desired swing amplitude X0 and desired swing frequency f of the output shaft 50, wherein the desired swing amplitude X0 is the theoretical swing amplitude in the design stage, which is set by the designer according to the actual working requirements of the crank-rocker mechanism.

[0033] S12. Obtain the crank swing radius BM corresponding to the desired swing amplitude X0, which can be understood as obtaining the standard crank swing radius BM. Specifically, this includes the following process: When the output shaft 50 of the crank-rocker mechanism is at the upper limit of the desired swing amplitude X0, the geometric dimensional relationship of the crank-rocker mechanism is as follows: Figure 6 As shown, the crank swing radius BM1 corresponding to the upper limit amplitude of the desired swing amplitude XO is calculated using the geometric dimensional relationships of the crank-rocker mechanism. The crank swing radius BM1 satisfies: BM1= sqrt(OA^2+OM^2-2*OA*OM*cos(a+X0))-AB; Where O is the rotation axis of the end of rocker arm 40 connected to output shaft 50 (or the axis of output shaft 50), A is the rotation axis of the end of rocker arm 40 pivotally connected to connecting rod 30, B is the rotation axis of the end of connecting rod 30 pivotally connected to lead screw sleeve 21, M is the axis of input shaft 10, OA is the length between the rotation axes of the two ends of rocker arm 40, AB is the length between the rotation axes of the two ends of connecting rod 30, and the crank swing radius BM is the distance between the pivot axis of lead screw sleeve 21 and connecting rod 30 and the axis of input shaft 10. a = arctan(AB / OA*cos(Xmax)). For Xmax, it can be understood that: in the design stage, Xmax is the maximum allowable swing amplitude of rocker arm 40, the expected swing amplitude X0 is the swing amplitude under ideal conditions, and the expected swing amplitude X0 ≤ Xmax. If the expected swing amplitude X0 is greater than Xmax, it may lead to a decrease in the working accuracy of the crank rocker mechanism or even failure. The terms BM, OA, AB, and a appearing below should also be understood in the same way as described above.

[0034] When the output shaft 50 of the crank-rocker mechanism is at the upper limit of the desired swing amplitude X0, the geometric dimensional relationship of the crank-rocker mechanism is as follows: Figure 7As shown. The crank-rocker mechanism's lower limit crank oscillation radius BM2, corresponding to the desired oscillation amplitude XO, is calculated using the geometric dimensional relationships of the crank-rocker mechanism. The crank oscillation radius BM2 satisfies: BM2= AB-sqrt(OA^2+OM^2-2*OA*OM*cos(a-X0)).

[0035] After obtaining the crank swing radius BM1 and crank swing radius BM2, the average value of the crank swing radius BM1 and crank swing radius BM2 is taken as the standard crank swing radius BM, that is, BM=(BM1+BM2) / 2. The reason for adopting this scheme is that due to the structural dimensions of the crank rocker mechanism itself, the values ​​of crank swing radius BM1 and crank swing radius BM2 will generally have slight differences. In order to reduce the influence of this slight difference on the accuracy of obtaining the standard motion curve F, the average value of crank swing radius BM1 and crank swing radius BM2 is taken as the standard crank swing radius value BM, and then step S13 or S15 is executed.

[0036] S13. Obtain the upper limit angle value X1 and the lower limit angle value X2 of the rocker arm corresponding to the crank swing radius BM. Specifically, this includes the following process: like Figure 9 As shown, when the rocker arm 40 of the crank-rocker mechanism is at its upper limit angle position, X1 is calculated based on the geometric dimensional relationships of the crank-rocker mechanism: X1= arccos((OA^2+OM^2-(AB+BM)^2) / (2*OA*OM))-a.

[0037] like Figure 11 As shown, when the rocker arm 40 of the crank-rocker mechanism is at its lower limit angle position, X2 is calculated using the geometric dimensional relationships of the crank-rocker mechanism: X2= a-arccos((OA^2+OM^2-(AB-BM)^2) / (2*OA*OM)).

[0038] S14. Obtain the standard amplitude A and the standard bias B: Since the expected swing amplitude X0 is a theoretical value from the design phase, it will deviate from the upper limit angle value X1 and the lower limit angle value X2. Generally speaking, X0 is between X1 and X2, that is, min(X1, X2) ≤ X0 ≤ max(X1, X2). In this embodiment, the average value of X1 and X2 is taken as the standard swing amplitude, that is, the amplitude A of the standard motion curve F is A=(X1+X2) / 2, and half of the difference between X1 and X2 is taken as the standard bias, that is, the bias B of the standard motion curve F is B=(X1-X2) / 2.

[0039] S15. Adjust the actual crank swing radius of the crank-rocker mechanism to the crank swing radius BM: By manually or by using a tool to turn the lead screw shaft 22, the lead screw sleeve 21 is forced to move, thereby adjusting the actual crank swing radius of the adjustable crank-rocker mechanism to the crank swing radius BM.

[0040] Through the aforementioned steps S11-S14, the amplitude A and the offset B can be obtained. After the amplitude A and the offset B are determined, the variation law of the standard motion curve F with respect to time can also be determined. By executing step S15, the crank swing radius BM of the drive device can be matched with the standard motion curve F. When the drive device operates with the crank swing radius BM, the upper limit angle value of its rocker arm is X1, and the lower limit angle value is X2.

[0041] In some embodiments, after determining the variation law of the standard motion curve F with respect to time, a phase reference for the standard motion curve F should also be set, which includes the following process: Please continue reading. Figure 5 , Figure 5 The output terminal can be understood as the output shaft 50 in this embodiment. When the joystick 40 is at the upper limit angle value X1, the motion curve F is at the 0 phase reference, that is... Figure 5 The initial position of the standard motion curve F in the equation; when the joystick 40 is at the lower limit angle value X2, the motion curve F is at the π phase reference, that is... Figure 5 The trough position of the standard motion curve F in the figure.

[0042] In some embodiments, step S2, the process of calculating the motion curve Fin of the input shaft 10 in reverse based on the standard motion curve F and the geometric dimensional relationship of the crank-rocker mechanism, includes: Input the motion curve Fin of shaft 10 as shown Figure 8 As shown, Figure 8 The input terminal in this embodiment can be understood as the input shaft 10. When the input shaft 10 rotates counterclockwise, it sequentially passes through the following two stages. In each stage, the motion curve Fin of the input shaft 10 satisfies: Phase 1: Combination Figure 8 , Figure 9 , Figure 10 and Figure 11 The output shaft 10 of the crank-rocker mechanism rotates counterclockwise, causing the rocker arm to swing from the upper limit angle X1 position to the lower limit angle X2 position, 0≤time≤0.5 / f, Fin=(∠AMB+∠AMO-(90°-a)); in, AM=sqrt(OA^2+OM^2-2*OA*OM*cos(a+F)); F=(X1+X2) / 2*cos(2*π*time*f)+(X1-X2) / 2; ∠AMB=arccos((AM^2+BM^2-AB^2) / (2*AM*BM)); ∠AMO=arccos((OM^2+AM^2-OA^2) / (2*OM*AM)).

[0043] Phase Two: Combination Figure 8 , Figure 11 and Figure 12 The output shaft 10 of the crank-rocker mechanism rotates counterclockwise, causing the rocker arm to swing from the lower limit angle X2 position to the upper limit angle X1 position. 0.5 / f<time≤1 / f, Fin=270°-(∠AMB-∠AMO-a); in, AM=sqrt(OA^2+OM^2-2*OA*OM*cos(a+F)); F=(X1+X2) / 2*cos(2*π*time*f)+(X1-X2) / 2; ∠AMB=arccos((AM^2+BM^2-AB^2) / (2*AM*BM)); ∠AMO=arccos((OM^2+AM^2-OA^2) / (2*OM*AM)).

[0044] In some embodiments, step S3, the process of generating a control signal based on the motion curve Fin to control the rotation of the servo motor shaft, includes: The operator inputs the corresponding control data (e.g., program code) through the controller's data input unit (e.g., keyboard). The controller's data processing unit can read the data stored in the data storage unit and, during the execution of the data, can send corresponding control signals to the servo motor to control the output shaft 50 of the servo motor to conform to the angle change patterns of the first, second, third, and fourth stages in step S2 during the rotation process.

[0045] In some embodiments, when the desired swing amplitude X0 and / or the desired swing frequency f changes, steps S1-S3 are repeated to reacquire the standard motion curve F.

[0046] In some embodiments of this application, an adjustable crank-rocker mechanism is provided, which adjusts the swing radius of the crank 20 to adjust the swing amplitude of the output shaft 50, so as to adapt to different action output requirements and improve the applicable scenarios of the adjustable crank-rocker mechanism.

[0047] In some embodiments of this application, a driving device and its phase compensation method are provided. In this method, based on the desired oscillation pattern of the output shaft 50 of the crank-rocker mechanism, a corresponding standard motion curve F is obtained. Based on the standard motion curve F, the motion curve Fin of the input shaft 10 is calculated in reverse. Based on the motion curve Fin, a control signal is formed to control the rotation of the servo motor shaft. Under the control of this control signal, the rotational speed of the servo motor shaft changes periodically, thereby driving the oscillation pattern of the rocker arm 40 of the adjustable crank-rocker mechanism to conform to a more standard cosine motion curve, overcoming the shortcomings of the traditional crank-rocker mechanism's inconsistent reciprocating speeds and quick-return motion characteristics.

[0048] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. An adjustable crank-rocker mechanism, characterized in that, It includes an input shaft (10), a crank (20), a connecting rod (30), a rocker arm (40), and an output shaft (50); the input shaft (10) is fixedly connected to the crank (20), the two ends of the connecting rod (30) are pivotally connected to the crank (20) and the rocker arm (40) respectively, and the output shaft (50) is fixedly connected to the end of the rocker arm (40) away from the connecting rod (30); wherein, the crank (20) includes a crank seat (23) and an adjustment component disposed on the crank seat (23), the adjustment component being configured to adjust the swing radius of the crank (20).

2. The adjustable crank-rocker mechanism as described in claim 1, characterized in that, The adjustment assembly includes a lead screw shaft (22) and a lead screw sleeve (21); the lead screw shaft (22) is rotatably mounted on the crank seat (23); the lead screw sleeve (21) is fitted onto the lead screw shaft (22) and threadedly connected to the lead screw shaft (22); the crank seat (23) is fixedly connected to the input shaft (10); and the lead screw sleeve (21) is pivotally connected to the connecting rod (30).

3. The adjustable crank-rocker mechanism as described in claim 2, characterized in that, The crank seat (23) is provided with a slide groove (231), a plurality of positioning holes (232) passing through the slide groove (231), and a positioning element (24) that can pass through the positioning holes (232); the slide groove (231) extends along the length direction of the lead screw shaft (22); the plurality of positioning holes (232) are arranged at intervals along the direction of extension of the slide groove (231); the lead screw sleeve (21) slides in the slide groove (231); the positioning element (24) passes through the positioning hole (232) corresponding to the position of the lead screw sleeve (21) and abuts against the lead screw sleeve (21) to limit the relative position of the lead screw sleeve (21) and the slide groove (231).

4. The adjustable crank-rocker mechanism as described in claim 3, characterized in that, The slide groove (231) is a dovetail groove, and the lead screw sleeve (21) has a dovetail-shaped structure (211) that is adapted to the shape of the dovetail groove. The dovetail-shaped structure (211) slides into the dovetail groove.

5. A driving device, characterized in that, The device includes a servo motor, an actuator, a controller, and an adjustable crank-rocker mechanism as described in any one of claims 1-4; the servo motor is configured to drive the input shaft (10) to rotate, and the output shaft (50) is configured to drive the actuator to perform an action; the controller is configured to send control signals to the servo motor.

6. A phase compensation method, characterized in that, It is used to control the operation of the drive device as described in claim 5; the phase compensation method includes the following process: Obtain the standard motion curve F corresponding to the desired swing law of the output shaft (50), wherein the standard motion curve F satisfies F=A*cos(2*π*time*f)+B; Based on the standard motion curve F, the motion curve Fin of the input shaft (10) is calculated in reverse using the geometric dimensional relationship of the crank-rocker mechanism; The motion curve Fin is used to generate control signals for controlling the rotation of the servo motor shaft.

7. The phase compensation method as described in claim 6, characterized in that, The process of obtaining the standard motion curve F corresponding to the desired oscillation law of the output shaft (50) includes: Set the desired swing amplitude X0 and desired swing frequency f of the output shaft (50); obtain the crank swing radius BM corresponding to the desired swing amplitude X0; adjust the actual crank swing radius of the crank rocker mechanism to the crank swing radius BM; obtain the upper limit angle value X1 and the lower limit angle value X2 of the rocker corresponding to the crank swing radius BM; where A=(X1+X2) / 2, B=(X1-X2) / 2.

8. The phase compensation method as described in claim 7, characterized in that, The process of obtaining the crank swing radius BM corresponding to the desired swing amplitude X0 includes: The crank swing radius BM1 corresponding to the upper limit amplitude of the desired swing amplitude XO is calculated using the geometric dimensions of the crank-rocker mechanism, and the crank swing radius BM2 corresponding to the lower limit amplitude of the desired swing amplitude XO is calculated using the geometric dimensions of the crank-rocker mechanism; BM=(BM1+BM2) / 2.

9. The phase compensation method as described in claim 7, characterized in that, When the rocker arm (40) is at the upper limit angle value X1, the motion curve F is at the 0 phase reference; when the rocker arm (40) is at the lower limit angle value X2, the motion curve F is at the π phase reference.

10. The phase compensation method as described in claim 7, characterized in that, When the desired swing amplitude X0 and / or desired swing frequency f change, the standard motion curve F is reacquired.

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