High-precision high-rigidity flexible coupling
By designing high-precision, high-rigidity flexible couplings, the limit structure of the fork and steel ball eliminates the biasing force, the problem of large measurement errors in the measurement of bearing rotation accuracy is solved, and high-precision torque and Speed transfer improves measurement accuracy and sensitivity.
Patent Information
- Application Number
- CN202411529258.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-30
- Publication Date
- 2025-01-10
AI Technical Summary
Traditional elastic couplings have large measurement errors in the measurement of bearing rotation accuracy, and the elastic element produces a reverse force after deformation, resulting in the inability to measure the true rotation accuracy of the bearing.
Design a high-precision, high-rigid flexible coupling, adopts a cross-axis-like limiting structure of forks A and forks B. The deviation force is eliminated through the displacement and deflection of the forks, and the interference matching between the steel ball and the square groove is used. It contacts the structure with point, accurately transmits torque and speed, and avoids reverse forces.
It realizes high-precision transmission of inelastic components, eliminates the rotation accuracy measurement error of the bearing, improves the deflection sensitivity and sliding movement sensitivity, and ensures the accuracy and stability of the measurement.
Smart Images
Figure CN119288996A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of mechanical manufacturing, and in particular to a high-precision and high-rigidity flexible coupling. Background Art
[0002] Bearings have been widely used in various fields of production and life, and the radial and end face runout of the inner and outer rings of the bearings are important parameter indicators for judging the rotation accuracy of the finished bearings. The size of the rotation accuracy will affect the operating stability and accuracy of the equipment, as well as the performance and life. It also affects the installation size of the bearing, the selection of precision bearings, the assembly of bearings, the installation and adjustment of bearings, etc.
[0003] Instruments and equipment for measuring bearing rotation accuracy, such as Figure 1 As shown, a motor is required to drive the rotating shaft through a coupling. A measuring fixture is installed below the rotating shaft and placed on the end face of the inner ring (or outer ring) of the bearing. This fixture then drives the inner ring (or outer ring) of the bearing to rotate for measurement purposes. A coupling is required between the motor shaft and the rotating shaft to transmit torque and speed. Traditional elastic couplings eliminate axial misalignment between the two shafts by deforming the elastic element. However, this deformation generates a certain amount of continuous reverse force. This reverse force is transmitted to the connected rotating shaft, which in turn transmits it to the bearing. Ultimately, this reverse force on the bearing causes an additional tilt angle, which increases measurement error and makes it impossible to measure the true rotational accuracy of the bearing.
[0004] How to design a high-precision, high-rigidity flexible coupling with ingenious design, simple structure, convenience and practicality, no elastic components, which can eliminate this deflection force through the displacement of the fork and ultimately eliminate the offset error of the two axes, accurately transmit torque and speed, and have high deflection sensitivity and sliding movement sensitivity is a problem that needs to be solved at present. Summary of the Invention
[0005] In order to solve the problems of large measurement errors in traditional elastic couplings when measuring the rotation accuracy of existing bearings, the reverse force generated after the elastic element is deformed, resulting in the inability to measure the true rotation accuracy of the bearings, etc., the present invention provides a high-precision and high-rigidity flexible coupling to achieve the goals of ingenious design, simple structure, convenience and practicality, no elastic elements, elimination of deflection force through the displacement and deflection of the fork, accurate transmission of torque and speed, and high deflection sensitivity and sliding sensitivity.
[0006] The technical solution adopted by the present invention to solve the above technical problems is: a high-precision and high-rigidity flexible coupling, including a shift fork A, a shift fork B and a connecting ring. The shift fork A and the shift fork B have the same structure, and the connecting ring is embedded between the shift forks A and B to form a cross-axis limiting structure.
[0007] As a further optimization scheme of the above-mentioned high-precision and high-rigidity flexible coupling, the shift fork A includes an intermediate plate A, two side plates A, two steel balls A, screws A, and a connecting shaft A. The intermediate plate A is a rectangular block structure. Reserved threaded holes are provided on both sides of the intermediate plate A. Through holes corresponding to the positions of the reserved threaded holes of the intermediate plate A are provided on the side plates A. The two side plates A are fixedly connected to the two sides of the intermediate plate A by screws A; steel balls A are provided on the inner sides of the two side plates A, threaded columns are fixed on the steel balls A, and threaded holes matching the threaded columns are provided on the lower part of the side plates A. The two steel balls A are connected by threads The shift fork B is fixed on the inner sides of the two side panels A; the shift fork B includes an intermediate panel B, two side panels B, two steel balls B, a screw B, and a connecting shaft B. The intermediate panel B is a rectangular block structure. Reserved threaded holes are provided on both sides of the intermediate panel B. Through holes corresponding to the positions of the reserved threaded holes of the intermediate panel B are provided on the side panels B. The two side panels B are fixedly connected to the two sides of the intermediate panel B by screws B; steel balls B are provided on the inner sides of the two side panels B, threaded columns are fixed on the steel balls B, and threaded holes matching the threaded columns are provided on the lower parts of the side panels B. The two steel balls B are fixed to the inner sides of the two side panels B by threaded connections.
[0008] As a further optimization scheme of the above-mentioned high-precision and high-rigidity flexible coupling, the connecting ring is a cylindrical structure, and two square grooves A are symmetrically opened on the upper end face of the connecting ring along the circumferential direction, and two square grooves B are also symmetrically opened on the lower end face of the connecting ring along the circumferential direction. The lines connecting the two square grooves A and the two square grooves B are perpendicular to each other, and the two square grooves A and the two square grooves B are both semi-open structures; the two steel balls A are respectively installed in the two square grooves B, and the two steel balls B are respectively installed in the two square grooves A, and the shift fork A and the shift fork B are limited by the cooperation of the steel ball A and the square groove B, and the steel ball B and the square groove A, respectively, with the connecting ring.
[0009] As a further optimization solution for the above-mentioned high-precision and high-rigidity flexible coupling, the dimensions between the steel ball A and the square groove B, and between the steel ball B and the square groove A are both interference fit.
[0010] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention includes a shift fork A, a shift fork B and a connecting ring. The shift fork A and the shift fork B have the same structure. The connecting ring is embedded between the shift fork A and the shift fork B to form a cross-axis type limiting structure.
[0011] 2. The main innovation of the present invention is that it provides a coupling without elastic elements for connecting the motor shaft and the rotating shaft. The centering error of the two shafts is eliminated by the free rotation angle of the fork itself and the free movement of the steel ball on the fork in the square groove of the connecting ring without generating any reverse force.
[0012] 3. The main innovation of the present invention is that the square groove is a semi-open structure and is not processed into a through groove. In this way, no matter whether the coupling is installed vertically or horizontally, the steel balls on the two shift forks limit the connecting ring through the bottom surface of the square groove, so that the coupling is connected as a whole and will not fall apart.
[0013] 4. The steel balls have an interference fit in the square groove, so when the coupling rotates, there is no travel clearance along the circumferential direction. The coupling can accurately transmit the speed and torque of the driving shaft.
[0014] 5. The contact surface between the steel ball and the square groove is point contact, so the friction force is extremely small when the steel ball rotates in the square groove. When the fork is subjected to extremely small external force in the rotation direction, it can rotate. The surface roughness of the steel ball and the square groove is extremely small, so the coupling has high deflection sensitivity and sliding movement sensitivity. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 This is a schematic diagram of the coupling measurement application status; Figure 2 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 3 This is a schematic diagram of the movement direction of the shift fork in the square groove of the connecting ring in a top view of the present invention; Figure 4 It is an exploded schematic diagram of the components of the present invention; Figure 5 This is a schematic diagram of the shift fork A deflected at a certain angle; Figure 6 This is a schematic diagram of the shift fork B deflected at a certain angle; Figure 7 2. It is a schematic diagram of the three-dimensional structure of the connecting ring; Figure 8 1. It is a schematic diagram of the three-dimensional structure of shift fork A; Figure 9 1 is a schematic diagram of the three-dimensional structure of shift fork B; Figure 10 It is a schematic diagram of the three-dimensional structure of the steel ball; Markings in the figure: 1 is shift fork A; 2 is shift fork B; 3 is connecting ring; 101 is middle plate A; 102 is side plate A; 103 is steel ball A; 104 is screw A; 105 is connecting shaft A; 201 is middle plate B; 202 is side plate B; 203 is steel ball B; 204 is screw B; 205 is connecting shaft B; 301 is square slot A; 302 is square slot B; 7 is motor; 8 is coupling; 9 is rotating shaft; 10 is measuring fixture; 11 is measured bearing; 12 is base. DETAILED DESCRIPTION
[0016] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.
[0017] like Figure 1 As shown, Figure 1 This is a schematic diagram of the coupling measurement application status in the existing technology; when measuring the bearing rotation accuracy, the motor is required to drive the rotating shaft to rotate through the coupling, and a measuring tool is installed on the lower part of the rotating shaft. The tool is placed on the end face of the inner ring (or outer ring end face) of the bearing, and then drives the inner ring (or outer ring) of the bearing to rotate to achieve the measurement purpose; a coupling is required between the motor shaft and the rotating shaft to transmit torque and speed. The traditional elastic coupling eliminates the axial centering deviation of the two shafts through the deformation of the elastic element, but the deformation of the elastic element will generate a certain size and continuous reverse force. This reverse force is transmitted to the rotating shaft connected to it, and the rotating shaft is then transmitted to the bearing. The final reverse force acting on the bearing will cause the bearing to produce an additional tilt angle, thereby increasing the measurement error and failing to measure the true rotation accuracy of the bearing.
[0018] like Figure 2 、 3 , 5, and 6, Figure 2 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 3 It is a schematic diagram of the top structure of the present invention; Figure 5 This is a schematic diagram of the shift fork A deflected at a certain angle; Figure 6 It is a schematic diagram of the shift fork B deflected at a certain angle; a high-precision and high-rigidity flexible coupling, including a shift fork A1, a shift fork B2 and a connecting ring 3. The shift forks A1 and B2 have the same structure, and the connecting ring 3 is embedded between the shift forks A1 and B2 to form a cross-axis type limiting structure.
[0019] like Figure 4 、 8 , 9, 10, Figure 8 1. It is a schematic diagram of the three-dimensional structure of shift fork A; Figure 9 1 is a schematic diagram of the three-dimensional structure of shift fork B; Figure 10It is a schematic diagram of the three-dimensional structure of the steel ball; the shift fork A1 includes an intermediate plate A101, two side plates A102, two steel balls A103, screws A104, and a connecting shaft A105. The intermediate plate A101 is a rectangular block structure. Reserved threaded holes are provided on both sides of the intermediate plate A101. Through holes corresponding to the positions of the reserved threaded holes of the intermediate plate A101 are provided on the side plates A102. The two side plates A102 are fixedly connected to the two sides of the intermediate plate A101 by screws A104; steel balls A103 are provided on the inner sides of the two side plates A102, and threaded columns are fixed on the steel balls A103. Threaded holes matching the threaded columns are provided on the lower parts of the side plates A102. The two steel balls A103 are fixed to the two side plates A101 through threaded connections. 02; the shift fork B2 includes an intermediate plate B201, two side plates B202, two steel balls B203, a screw B204, and a connecting shaft B205. The intermediate plate B201 is a rectangular block structure. Reserved threaded holes are provided on both sides of the intermediate plate B201. Through holes corresponding to the positions of the reserved threaded holes of the intermediate plate B201 are provided on the side plates B202. The two side plates B202 are fixedly connected to the two sides of the intermediate plate B201 by screws B204; steel balls B203 are provided on the inner sides of the two side plates B202, and threaded columns are fixed on the steel balls B203. Threaded holes matching the threaded columns are provided on the lower parts of the side plates B202. The two steel balls B203 are fixed to the inner sides of the two side plates B202 by threaded connections.
[0020] like Figure 7 、 10 As shown, Figure 7 2. It is a schematic diagram of the three-dimensional structure of the connecting ring; Figure 10 It is a schematic diagram of the three-dimensional structure of the steel ball; the connecting ring 3 is a cylindrical structure, and the upper end face of the connecting ring 3 is symmetrically provided with two square grooves A301 along the circumferential direction, and the lower end face of the connecting ring 3 is also symmetrically provided with two square grooves B302 along the circumferential direction, and the connecting line of the two square grooves A301 and the two square grooves B302 is perpendicular to each other, and the two square grooves A301 and the two square grooves B302 are both semi-open structures; the square grooves are all semi-open structures and are not processed into through grooves, so that no matter whether the coupling is installed vertically or horizontally, the steel balls on the two shift forks limit the connecting ring through the square grooves, so that the coupling is connected into a whole and will not fall apart.
[0021] The two steel balls A103 are mounted in the two square grooves B302, and the two steel balls B203 are mounted in the two square grooves A301. The shift fork A1 and shift fork B2 are respectively restrained by the connection ring 3 through the fit between the steel balls A103 and the square grooves B302, and between the steel balls B203 and the square grooves A301. The steel balls A103 and B203 each have an interference fit with the square grooves B302 and A301, respectively, with an interference fit of 2 to 3 μm. This interference fit of the steel balls within the square grooves ensures zero circumferential play during coupling rotation, enabling the coupling to accurately transmit the speed and torque of the drive shaft. In specific applications, the steel balls installed on the two forks have a precision of G5 grade. Referring to the provisions of GB / T308.1-2013, the surface roughness of the steel balls is not greater than 0.014μm. The inner surface of the square groove of the connecting ring is a ground surface with a roughness precision of not greater than 0.08μm. The ends of the forks are connected to the driving device and the rotating shaft by means of threads and keyways respectively.
[0022] refer to Figure 1 and Figure 3 When the coupling connects two shafts, due to the existence of offset error in the installation error of the two shafts, a deflection force will be generated. This deflection force is transmitted to the fork, which will cause the steel ball on the fork to produce a displacement in the square groove of the connecting ring, such as Figure 3 As shown, the bias force is eliminated by the displacement of the shift fork, and ultimately the offset error of the two axes is eliminated.
[0023] refer to Figure 1 and Figure 5 、 6 When the coupling connects two shafts, due to the existence of angular error in the installation error of the two shafts, an overturning moment will be generated. This overturning moment is transmitted to the fork, and the fork will rotate an angle with the center line of the two steel balls as the rotation axis, such as Figure 5 、 6 As shown in the figure, the angular error between the two axes can be eliminated by rotating the shift fork by an angle.
[0024] The contact surface between the steel ball and the square groove is point contact, so the friction force when the steel ball rotates in the square groove is extremely small. When the fork is subjected to extremely small external force in the rotation direction, it can rotate. The surface roughness of the steel ball and the square groove is extremely small, so the coupling has high deflection sensitivity and sliding movement sensitivity.
[0025] In practical applications, the connecting shaft A105 and the connecting shaft B205 can be selected as threaded shafts or keyed shafts according to the type of motion shaft joints connected to their ends, but the present solution is not limited thereto.
[0026] The present invention has an ingenious design, a simple structure, is convenient and practical, has no elastic elements, eliminates the biasing force through the displacement and deflection of the fork, accurately transmits torque and rotation speed, has high deflection sensitivity and sliding movement sensitivity, and solves the problems of large measurement errors in conventional elastic couplings when measuring the rotation accuracy of existing bearings, and reverse forces generated after deformation of elastic elements, which makes it impossible to measure the true rotation accuracy of the bearings. Compared with the existing technology, the present invention has good market prospects and development space.
[0027] The preferred specific implementation modes and embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above implementation modes and embodiments. Various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the concept of the present invention.
Claims
1. A high-precision and high-rigidity flexible coupling, characterized in that: The invention comprises a shift fork A (1), a shift fork B (2) and a connecting ring (3), wherein the shift fork A (1) and the shift fork B (2) have the same structure, and the connecting ring (3) is embedded between the shift fork A (1) and the shift fork B (2) to form a cross-axis-like limiting structure.
2. A high-precision and high-rigidity flexible coupling as claimed in claim 1, characterized in that: The shift fork A (1) comprises an intermediate plate A (101), two side plates A (102), two steel balls A (103), a screw A (104), and a connecting shaft A (105); the intermediate plate A (101) is a rectangular block structure; both sides of the intermediate plate A (101) are provided with reserved threaded holes; the side plates A (102) are provided with through holes corresponding to the positions of the reserved threaded holes of the intermediate plate A (101); the two side plates A (102) are respectively fixedly connected to both sides of the intermediate plate A (101) by means of the screws A (104); the inner sides of the two side plates A (102) are provided with steel balls A (103); threaded columns are fixedly provided on the steel balls A (103); threaded holes matching the threaded columns are provided at the lower parts of the side plates A (102); the two steel balls A (103) are fixedly connected to the inner sides of the two side plates A (102) by means of threaded connections; The shift fork B (2) comprises an intermediate plate B (201), two side plates B (202), two steel balls B (203), a screw B (204), and a connecting shaft B (205); the intermediate plate B (201) is a rectangular block structure; both sides of the intermediate plate B (201) are provided with reserved threaded holes; the side plates B (202) are provided with through holes corresponding to the positions of the reserved threaded holes of the intermediate plate B (201); the two side plates B (202) are respectively fixedly connected to both sides of the intermediate plate B (201) by means of the screws B (204); the inner sides of the two side plates B (202) are provided with steel balls B (203); threaded columns are fixedly provided on the steel balls B (203); threaded holes matching the threaded columns are provided at the lower parts of the side plates B (202); the two steel balls B (203) are fixedly connected to the inner sides of the two side plates B (202) by means of threaded connection.
3. A high-precision and high-rigidity flexible coupling as claimed in claim 2, characterized in that: The connecting ring (3) is a cylindrical structure. The upper end surface of the connecting ring (3) is symmetrically provided with two square grooves A (301) along the circumferential direction. The lower end surface of the connecting ring (3) is also symmetrically provided with two square grooves B (302) along the circumferential direction. The connecting lines of the two square grooves A (301) and the two square grooves B (302) are perpendicular to each other. The two square grooves A (301) and the two square grooves B (302) are both semi-open structures. The two steel balls A (103) are respectively installed in the two square grooves B (302). The two steel balls B (203) are respectively installed in the two square grooves A (301). The shift fork A (1) and the shift fork B (2) are respectively limited by the matching of the steel ball A (103) and the square groove B (302) and the steel ball B (203) and the square groove A (301) with the connecting ring (3).
4. A high-precision and high-rigidity flexible coupling as claimed in claim 3, characterized in that: The dimensions between the steel ball A (103) and the square groove B (302), and between the steel ball B (203) and the square groove A (301) are both interference fits.