Three-wave harmonic reducer

Abstract

The utility model relates to the technical field of speed reducers, and particularly discloses a three-wave harmonic speed reducer which is characterized in that a rigid gear is meshed with the periphery of a flexible gear, and a harmonic generator is arranged in the flexible gear; the difference between the rigid gear teeth and the flexible gear teeth is 3; the tooth profile of one tooth of the flexible gear is composed of seven circular arcs which are sequentially connected in a tangent mode, and the radiuses of the seven circular arcs are 1.2477 mm, 13.4153 mm, 2.9319 mm, 0.8033 mm, 2.9319 mm, 13.4153 mm and 1.2477 mm in sequence. The tooth profile of one tooth of the rigid gear is composed of seven circular arcs which are sequentially connected in a tangent mode, and the radiuses of the seven circular arcs are 0.3339 mm, 7.2248 mm, 3.7611 mm, 1.0840 mm, 3.7611 mm, 7.2248 mm and 0.3339 mm in sequence. Through the arrangement, the meshing precision and the transmission stability of the three-wave harmonic reducer are improved.

Description

Technical Field

[0001] This utility model relates to the field of speed reducer technology, and in particular to a three-wave harmonic speed reducer. Background Technology

[0002] Harmonic gear reducers are devices that use a wave generator to produce controllable elastic deformation waves from flexible gears to achieve motion and power transmission. Due to their relatively stable motion characteristics, harmonic reducers are widely used in industries such as electronics, aerospace, automation equipment, CNC equipment, and robotics. Existing three-wave harmonic reducers generally have a transmission ratio greater than 30, and the meshing ratio of the flexible gear and the rigid gear is between 20% and 30%, resulting in poor load-bearing capacity and unsuitability for high-rigidity applications. Increasing the meshing ratio of the flexible gear and the rigid gear can lead to excessive deformation of the flexible gear, thereby affecting meshing accuracy and transmission stability.

[0003] Therefore, it is urgent to study a three-wave harmonic reducer to solve the above problems. Utility Model Content

[0004] The purpose of this invention is to provide a three-wave harmonic reducer to solve the problems in the prior art where the meshing area between the flexible wheel and the rigid wheel is small, resulting in poor load-bearing capacity and unsuitability for high-rigidity applications, as well as the problem that the transmission ratio is high and greater than 30, leading to slow response.

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

[0006] A three-wave harmonic reducer includes a flexible wheel, a rigid wheel, and a harmonic generator. The rigid wheel meshes with the outer circumference of the flexible wheel. The harmonic generator has three protrusions located inside the flexible wheel. These protrusions lift the corresponding teeth of the flexible wheel and engage them with the teeth of the rigid wheel. The teeth of the flexible wheel corresponding to the center of the transition section connecting the protrusions remain disengaged from the teeth of the rigid wheel. Here, Zc is the number of teeth on the rigid wheel, Zf is the number of teeth on the flexible wheel, and Zc - Zf = 3. The tooth profile of one tooth on the flexible wheel is composed of seven sequentially tangentially connected circular arcs, where the radii of the seven arcs are... The radii are 1.2477mm, 13.4153mm, 2.9319mm, 0.8033mm, 2.9319mm, 13.4153mm, and 1.2477mm respectively; the profile of one tooth of the rigid wheel is composed of seven sequentially connected tangential arcs, with the radii of the seven arcs being 0.3339mm, 7.2248mm, 3.7611mm, 1.0840mm, 3.7611mm, 7.2248mm, and 0.3339mm respectively.

[0007] As an optional technical solution for a three-wave harmonic reducer, the rigid wheel has 33 teeth and the flexible wheel has 30 teeth.

[0008] As an optional technical solution for a three-wave harmonic reducer, based on the tooth root radius, the maximum heights of the seven arc segments in the flexspline are, sequentially, 0.1038mm, 0.3616mm, 0.5882mm, 0.6125mm, 0.5882mm, 0.3616mm, and 0.1038mm; and / or,

[0009] Of the seven arcs in the flexure, the three middle arcs bend towards the center of the flexure, while the four arcs on either side bend away from the center of the flexure.

[0010] As an optional technical solution for a three-wave harmonic reducer, the tooth pitch of the flexure is 3.6522mm.

[0011] As an optional technical solution for a three-wave harmonic reducer, the total length of the three arc segments in the middle of one tooth of the flex wheel is 1.6062mm.

[0012] As an optional technical solution for a three-wave harmonic reducer, based on the tooth root radius, the maximum heights of the seven arc segments in the rigid wheel are, respectively, 0.0283mm, 0.1943mm, 0.4903mm, 0.5256mm, 0.4903mm, 0.1943mm, and 0.0283mm; and / or,

[0013] Of the seven circular arcs in the rigid wheel, the three middle arcs bend towards the center of the rigid wheel, while the four arcs on both sides bend away from the center of the rigid wheel.

[0014] As an optional technical solution for a three-wave harmonic reducer, the tooth pitch of the rigid wheel is 3.3910mm.

[0015] As an optional technical solution for a three-wave harmonic reducer, the total length of the three arc segments in the middle of one tooth of the rigid wheel is 2.0932mm.

[0016] As an optional technical solution for a three-wave harmonic reducer, the reduction ratio of the three-wave harmonic reducer is 10.

[0017] As an optional technical solution for a three-wave harmonic reducer, the flexible wheel is made of alloy steel; and / or,

[0018] The rigid wheel is made of alloy steel.

[0019] This utility model has at least the following beneficial effects:

[0020] This invention provides a three-wave harmonic reducer, which includes a flexible wheel, a rigid wheel, and a harmonic generator. The rigid wheel meshes with the outer circumference of the flexible wheel. The harmonic generator has three protrusions located inside the flexible wheel. The protrusions lift the teeth of the flexible wheel at corresponding positions and mesh with the teeth of the rigid wheel. The teeth of the flexible wheel corresponding to the center of the transition section connecting the protrusions remain disengaged from the teeth of the rigid wheel. By limiting the number and size of the teeth of the flexible wheel and the rigid wheel, the meshing area between the rigid wheel and the flexible wheel is 40.9%, which significantly improves the load-bearing capacity of the three-wave harmonic reducer and enables it to adapt to applications with higher stiffness. At the same time, the three meshing points between the flexible wheel and the rigid wheel in the three-wave reducer result in less deformation of the flexible wheel, thereby ensuring meshing accuracy and transmission stability. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of this utility model and these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of a single tooth of the flexible wheel in the three-wave harmonic reducer of this utility model embodiment;

[0023] Figure 2 This is a schematic diagram of the structure of a single tooth of a rigid wheel in the three-wave harmonic reducer of this utility model embodiment, which is expanded with respect to the tooth root radius.

[0024] Figure 3 This is a schematic diagram of the meshing structure of the flexible wheel and rigid wheel in the three-wave harmonic reducer of this utility model embodiment.

[0025] In the picture:

[0026] 10. Flexible wheel; 20. Rigid wheel;

[0027] 100. Soft tooth root line; 110. First soft arc; 120. Second soft arc; 130. Third soft arc; 140. Fourth soft arc; 150. Fifth soft arc; 160. Sixth soft arc; 170. Seventh soft arc;

[0028] 200, rigid tooth root line; 210, first rigid arc; 220, second rigid arc; 230, third rigid arc; 240, fourth rigid arc; 250, fifth rigid arc; 260, sixth rigid arc; 270, seventh rigid arc. Detailed Implementation

[0029] Before explaining any implementation of this application in detail, it should be understood that this application is not limited to its application to the structural details and component arrangements set forth in the following description or shown in the above drawings.

[0030] In this application, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0031] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this application generally indicates that the preceding and following related objects have an "and / or" relationship.

[0032] In this application, the terms "connection," "combination," "coupling," and "installation" can refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, a direct connection refers to two parts or components being connected together without the need for an intermediary, while an indirect connection refers to two parts or components each being connected to at least one intermediary, with the connection achieved through the intermediary. Furthermore, "connection" and "coupling" are not limited to physical or mechanical connections or couplings, but can also include electrical connections or couplings.

[0033] In this application, those skilled in the art will understand that relative terms (e.g., “about,” “approximately,” “basically,” etc.) used in conjunction with quantities or conditions are to include the values ​​and have the meaning indicated by the context. For example, such relative terms include at least the degree of error associated with the measurement of a particular value, tolerances associated with the particular value due to manufacturing, assembly, use, etc. Such terms should also be considered as disclosing a range defined by the absolute values ​​of the two endpoints. Relative terms may refer to a certain percentage (e.g., 1%, 5%, 10% or more) of the indicated value. Numerical values ​​not using relative terms should also be disclosed as specific values ​​with tolerances. Furthermore, “basically” when expressing relative angular relationships (e.g., substantially parallel, substantially perpendicular) may refer to a certain degree (e.g., 1 degree, 5 degrees, 10 degrees or more) added to or subtracted from the indicated angle.

[0034] In this application, those skilled in the art will understand that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.

[0035] In this application, the directional terms "upper," "lower," "left," "right," "front," and "rear" are used to describe the orientation and positional relationships shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when an element is mentioned as being connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected through an intermediate element. It should also be understood that directional terms such as upper side, lower side, left side, right side, front side, and rear side not only represent positive orientation but can also be understood as lateral orientation. For example, "below" can include directly below, lower left, lower right, lower front, and lower rear.

[0036] like Figures 1 to 3 As shown, this embodiment provides a three-wave harmonic reducer, which includes a flexible wheel 10, a rigid wheel 20, and a harmonic generator. The rigid wheel 20 meshes with the outer periphery of the flexible wheel 10. The harmonic generator has three protrusions located inside the flexible wheel 10. The protrusions lift the teeth of the flexible wheel 10 at corresponding positions and mesh with the teeth of the rigid wheel 20. The teeth of the flexible wheel 10 corresponding to the center of the transition section connecting the protrusions remain disengaged from the teeth of the rigid wheel 20. Zc is the number of teeth of the rigid wheel 20, Zf is the number of teeth of the flexible wheel 10, and Zc-Zf = 3. The tooth profile of one tooth of the flexible wheel 10 consists of seven segments... The tooth profile of one tooth of the rigid wheel 20 is composed of seven sequentially tangent circular arcs, with radii of 1.2477mm, 13.4153mm, 2.9319mm, 0.8033mm, 2.9319mm, 13.4153mm, and 1.2477mm respectively.

[0037] In other words, the flexible gear 10 is unfolded with its own tooth root radius to form a straight flexible tooth root line 100 and the tooth profile of the flexible gear 10 on the flexible tooth root line 100. The seven arcs in the tooth profile of one tooth of the flexible gear 10 are defined as the first flexible arc 110, the second flexible arc 120, the third flexible arc 130, the fourth flexible arc 140, the fifth flexible arc 150, the sixth flexible arc 160, and the seventh flexible arc 170 connected in sequence. Among them, the radius of the first flexible arc 110 is 1.2477 mm, the radius of the second flexible arc 120 is 13.4153 mm, the radius of the third flexible arc 130 is 2.9319 mm, the radius of the fourth flexible arc 140 is 0.8033 mm, the radius of the fifth flexible arc 150 is 2.9319 mm, the radius of the sixth flexible arc 160 is 13.4153 mm, and the radius of the seventh flexible arc 170 is 1.2477 mm. In this embodiment, the bending directions of the first flexible arc 110, the second flexible arc 120, the sixth flexible arc 160 and the seventh flexible arc 170 are away from the center of the flexible wheel 10, while the bending directions of the third flexible arc 130, the fourth flexible arc 140 and the fifth flexible arc 150 are towards the center of the flexible wheel 10.

[0038] After unfolding the rigid wheel 20 with its own tooth root radius, a straight rigid tooth root line 200 is formed and the tooth profile of the rigid wheel 20 on the rigid tooth root line 200 is formed. The seven circular arcs of one tooth of the rigid wheel 20 are defined as the first rigid circular arc 210, the second rigid circular arc 220, the third rigid circular arc 230, the fourth rigid circular arc 240, the fifth rigid circular arc 250, the sixth rigid circular arc 260, and the seventh rigid circular arc 270 connected in sequence. Among them, the radius of the first rigid circular arc 210 is 0.3339 mm, the radius of the second rigid circular arc 220 is 7.2248 mm, the radius of the third rigid circular arc 230 is 3.7611 mm, the radius of the fourth rigid circular arc 240 is 1.0840 mm, the radius of the fifth rigid circular arc 250 is 3.7611 mm, the radius of the sixth rigid circular arc 260 is 7.2248 mm, and the radius of the seventh rigid circular arc 270 is 0.3339 mm. In this embodiment, the bending directions of the first rigid arc 210, the second rigid arc 220, the sixth rigid arc 260 and the seventh rigid arc 270 are away from the center of the rigid wheel 20, while the bending directions of the third rigid arc 230, the fourth rigid arc 240 and the fifth rigid arc 250 are towards the center of the rigid wheel 20.

[0039] The harmonic generator includes a cam, and the curve expression of the cam is p = 12.535 + 0.23 * cos(3 * θ).

[0040] Combination Figure 3As shown, the rigid wheel 20 and the flexible wheel 10 mesh at three points, A1, A2, and A3, with an angle of 98.182° in each meshing area. This results in a meshing area of ​​40.9% between the rigid wheel 20 and the flexible wheel 10 in the three-wave harmonic reducer, which significantly improves the load-bearing capacity of the three-wave harmonic reducer and enables it to adapt to applications with higher stiffness. At the same time, the flexible wheel 10 and the rigid wheel 20 in the three-wave reducer have three meshing points, and the deformation of the flexible wheel 10 is small, thus ensuring meshing accuracy and transmission stability.

[0041] The polar coordinate expression of the neutral layer curve of the flexible wheel 10 is as follows:

[0042] The rotation angle of the undeformed end of the flexible wheel 10 is The rotation angle of the rigid wheel is r = [17.023 + 0.23 * cos(3θ)] / cos(μ), (0 ≤ θ ≤ 2π).

[0043] μ is the angle between the center line of the flexible gear tooth and the radius vector, expressed as:

[0044] μ = tan -1 {30.23sin(3θ) / [17.023+0.23*cos(3θ)]};

[0045] The rotation angle of the undeformed end of the flexible wheel 10 is The rotation angle of the rigid wheel is Ф. In the formula, Z c For a rigid wheel with 20 teeth, Z f The number of teeth on the flexible wheel 10 is [number of teeth]. In this embodiment, the rigid wheel 20 has 33 teeth; the flexible wheel 10 has 30 teeth, i.e.

[0046] The tooth profile of rigid wheel 20 is calculated using envelope theory, which is as follows:

[0047]

[0048] It should be noted that the envelope theory above calculates the tooth profile of half a tooth of the rigid wheel 20, the tooth profile of the entire tooth is obtained by mirroring, and the outline of the entire rigid wheel 20 can be obtained by circumferential array. In some embodiments, unfolded with the tooth root radius, the maximum heights of the seven arc segments in the flexible wheel 10 are 0.1038mm, 0.3616mm, 0.5882mm, 0.6125mm, 0.5882mm, 0.3616mm, and 0.1038mm, respectively. In other words, the distance H11 from the connection point of the first flexible arc 110 and the second flexible arc 120 to the root line 100 of the flexible tooth is 0.1038 mm; the distance H12 from the connection point of the second flexible arc 120 and the third flexible arc 130 to the root line 100 of the flexible tooth is 0.3616 mm; the distance H13 from the connection point of the third flexible arc 130 and the fourth flexible arc 140 to the root line 100 of the flexible tooth is 0.5882 mm; and the midpoint of the fourth flexible arc 140... The distance H14 from the flexible tooth root line 100 is 0.6125 mm; the distance from the connection point of the fourth flexible arc 140 and the fifth flexible arc 150 to the flexible tooth root line 100 is 0.5882 mm; the distance from the connection point of the fifth flexible arc 150 and the sixth flexible arc 160 to the flexible tooth root line 100 is 0.3616 mm; and the distance from the connection point of the sixth flexible arc 160 and the seventh flexible arc 170 to the flexible tooth root line 100 is 0.1038 mm.

[0049] In some embodiments, the tooth pitch L11 of the flexible gear 10 is 3.6522 mm. The length L12 of the three arc segments in the middle of one tooth of the flexible gear 10 is 1.6062 mm. In other words, the length L12 of the third flexible arc 130, the fourth flexible arc 140, and the fifth flexible arc 150 is 1.6062 mm. In two adjacent teeth of the flexible gear 10, the total length L13 of the sixth flexible arc 160 and the seventh flexible arc 170 of the preceding tooth and the first flexible arc 110 and the second flexible arc 120 of the following tooth is 2.046 mm.

[0050] Expanding with respect to the tooth root radius, the maximum heights of the seven arc segments in the rigid wheel 20 are, respectively, 0.0283mm, 0.1943mm, 0.4903mm, 0.5256mm, 0.4903mm, 0.1943mm, and 0.0283mm. In other words, the distance H21 from the connection point of the first rigid arc 210 and the second rigid arc 220 to the rigid tooth root line 200 is 0.0283mm; the distance H22 from the connection point of the second rigid arc 220 and the third rigid arc 230 to the rigid tooth root line 200 is 0.1943mm; the distance H23 from the connection point of the third rigid arc 230 and the fourth rigid arc 240 to the rigid tooth root line 200 is 0.4903mm; and the distance H23 from the midpoint of the fourth rigid arc 240 is... The distance H24 from the rigid tooth root line 200 is 0.5256mm; the distance from the connection point of the fourth rigid arc 240 and the fifth rigid arc 250 to the rigid tooth root line 200 is 0.4903mm; the distance from the connection point of the fifth rigid arc 250 and the sixth rigid arc 260 to the rigid tooth root line 200 is 0.1943mm; and the distance from the connection point of the sixth rigid arc 260 and the seventh rigid arc 270 to the rigid tooth root line 200 is 0.0283mm.

[0051] The tooth pitch L21 of the rigid gear 20 is 3.3910 mm. The length L22 of the three circular arcs in the middle of one tooth of the rigid gear 20 is 2.0932 mm. The reduction ratio of the three-wave harmonic reducer is 10, which significantly improves the response speed. In other words, the length L22 of the third rigid arc 230, the fourth rigid arc 240, and the fifth rigid arc 250 is 2.0932 mm. In two adjacent teeth of the rigid gear 20, the total length L23 of the sixth rigid arc 260 and the seventh rigid arc 270 of the preceding tooth, and the first rigid arc 210 and the second rigid arc 220 of the following tooth is 1.2979 mm.

[0052] In some embodiments, the flexible wheel 10 is made of alloy steel. The rigid wheel 20 is made of alloy steel.

[0053] The three-wave harmonic reducer also includes a flexible bearing. The outer wall of the harmonic generator is connected to the inner wall of the flexible bearing, and the outer wall of the flexible bearing is connected to the inner wall of the flexure 10. The harmonic generator includes an input shaft and a cam, and the circumference of the outer wall of the cam is equal to the circumference of the inner wall of the flexible bearing.

[0054] In some embodiments, the flexible wheel 10 has a flange section and a gear ring section; the flange section and the gear ring section are connected by a transition surface; 30 teeth of the flexible wheel 10 are located on the outside of the gear ring section, and the harmonic generator is located inside the gear ring section. The rigid wheel 20 avoids the transition surface. Straight flange transition sections and gear ring transition sections are respectively provided at both ends of the transition surface, and the total length of the flange transition section and the gear ring transition section is less than the radius of curvature of the transition surface. The transition surface is tangent to the flange transition section to ensure connection stability and avoid stress concentration.

[0055] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A three-wave harmonic reducer, characterized in that, Includes a flexible wheel (10), a rigid wheel (20), and a harmonic generator. The rigid wheel (20) meshes with the outer circumference of the flexible wheel (10). The harmonic generator has three protrusions located inside the flexible wheel (10). The protrusions lift the teeth of the flexible wheel (10) at the corresponding positions and mesh with the teeth of the rigid wheel (20). The teeth of the flexible wheel (10) corresponding to the center of the transition section connecting the protrusions remain disengaged from the teeth of the rigid wheel (20). Zc is the number of teeth of the rigid wheel, Zf is the number of teeth of the flexible wheel (10), and Zc-Zf=3. The tooth profile of one tooth of the flexible wheel (10) is composed of seven segments connected tangentially in sequence. The tooth profile of one tooth of the rigid wheel (20) is composed of seven tangentially connected arcs, with the radii of the seven arcs being 1.2477mm, 13.4153mm, 2.9319mm, 0.8033mm, 2.9319mm, 13.4153mm, and 1.2477mm respectively.

2. The three-wave harmonic reducer according to claim 1, characterized in that, The rigid wheel (20) has 33 teeth, and the flexible wheel (10) has 30 teeth.

3. The three-wave harmonic reducer according to claim 1, characterized in that, Expanding with respect to the tooth root radius, the maximum heights of the seven arc segments in the flexible gear (10) are, respectively, 0.1038 mm, 0.3616 mm, 0.5882 mm, 0.6125 mm, 0.5882 mm, 0.3616 mm, and 0.1038 mm; and / or, Of the seven arc segments in the flexible wheel (10), the three middle arc segments bend towards the center of the flexible wheel (10), while the four arc segments on both sides bend away from the center of the flexible wheel (10).

4. The three-wave harmonic reducer according to claim 3, characterized in that, The tooth pitch of the flexible wheel (10) is 3.6522 mm.

5. The three-wave harmonic reducer according to claim 3, characterized in that, The total length of the three arc segments in the middle of one tooth of the flexible wheel (10) is 1.6062 mm.

6. The three-wave harmonic reducer according to claim 3, characterized in that, Expanding with respect to the tooth root radius, the maximum heights of the seven arc segments in the rigid wheel (20) are, respectively, 0.0283 mm, 0.1943 mm, 0.4903 mm, 0.5256 mm, 0.4903 mm, 0.1943 mm, and 0.0283 mm; and / or, Of the seven arc segments in the rigid wheel (20), the three middle arc segments bend towards the center of the rigid wheel (20), while the four arc segments on both sides bend away from the center of the rigid wheel (20).

7. The three-wave harmonic reducer according to any one of claims 1-6, characterized in that, The tooth pitch of the steel wheel (20) is 3.3910 mm.

8. The three-wave harmonic reducer according to claim 7, characterized in that, The total length of the three arc segments in the middle of one tooth of the rigid wheel (20) is 2.0932 mm.

9. The three-wave harmonic reducer according to claim 7, characterized in that, The reduction ratio of the three-wave harmonic reducer is 10.

10. The three-wave harmonic reducer according to claim 1, characterized in that, The flexible wheel (10) is made of alloy steel; and / or, The rigid wheel (20) is made of alloy steel.

Images