transmission mechanism

Abstract

This application discloses a transmission mechanism comprising a first internal gear, a second internal gear, a first external gear, a second external gear, an input shaft, a connecting disc, a first planetary converter, and a second planetary converter. The first external gear meshes with the first internal gear. The second external gear meshes with the second internal gear. The input shaft has a first eccentric portion and a second eccentric portion with the same eccentric direction but different eccentricities. The first eccentric portion drives the first external gear to rotate, and the second eccentric portion drives the second external gear to rotate. The connecting disc is disposed between the first external gear and the second external gear. The first planetary converter connects the first external gear and the connecting disc. The second planetary converter connects the connecting disc and the second external gear. The transmission mechanism of this application has the advantages of being easy to manufacture, having high rigidity, and having a small axial dimension.

Description

Technical Field

[0001] This application relates to transmission mechanisms, and more particularly to transmission mechanisms having a gear system. Background Technology

[0002] Traditional gear transmission mechanisms mostly employ two identical external gears, each mounted symmetrically on an input shaft with equal eccentricity and a 180° eccentricity direction. The transmission mechanism uses a pin-and-sleeve structure to output the rotational speed and eccentric torque of the external gears via an output element. However, transmission mechanisms using a pin-and-sleeve structure require machining multiple holes in both the external gears and the output element to accommodate the pins. Summary of the Invention

[0003] This application provides a transmission mechanism including a first internal gear, a second internal gear, a first external gear, a second external gear, an input shaft, a connecting disc, a first planetary converter, and a second planetary converter. The input shaft has a first eccentric portion and a second eccentric portion with the same eccentric direction but different eccentricities. The output element is rotatably disposed. The first internal gear is connected to a fixed side, and the second internal gear is connected to the output element. The first external gear and the second external gear are respectively sleeved on the first eccentric portion and the second eccentric portion, and respectively mesh with the first internal gear and the second internal gear. The connecting disc is disposed between the first external gear and the second external gear. The first planetary converter connects the first external gear and the connecting disc, and is configured to enable the first external gear to perform planetary motion under the drive of the input shaft and convert the planetary motion of the first external gear into rotational motion of the connecting disc. The second planetary converter connects the connecting disc and the second external gear, and is configured to enable the second external gear to drive the second internal gear to rotate under the drive of the input shaft.

[0004] According to the transmission mechanism, the first eccentric part has a first eccentricity d1, and the second eccentric part has a second eccentricity d2. The first eccentricity d of the first eccentric part and the second eccentricity d of the second eccentric part on the input shaft satisfy the following conditions: in, n1 is the number of teeth on the first external gear, and n2 is the number of teeth on the first internal gear. n3 is the number of teeth on the second external gear, and n4 is the number of teeth on the second internal gear.

[0005] According to the transmission mechanism, the first eccentricity d1 of the first eccentric portion and the second eccentricity d2 of the second eccentric portion on the input shaft satisfy the following conditions:

[0006] According to the transmission mechanism, the first external gear and the first internal gear form a first-stage meshing, and the second external gear and the second internal gear form a second-stage meshing, with the first-stage meshing and the second-stage meshing having different transmission speed ratios.

[0007] According to the transmission mechanism, the first planetary converter is configured to cause the first external gear to drive the connecting disk to rotate synchronously, and to allow the first external gear to move linearly relative to the connecting disk. The second planetary converter is configured to cause the connecting disk to drive the second external gear to rotate synchronously, and to allow the second external gear to move linearly relative to the connecting disk.

[0008] According to the transmission mechanism, the first planetary conversion device is a first linear bearing or a first linear slider with a structure disposed on the first external gear and the connecting disk, and the second planetary conversion device is a second linear bearing or a second linear slider with a structure disposed on the second external gear and the connecting disk, wherein the second linear bearing or the second linear slider is arranged at 90° with the first linear bearing or the first linear slider around the central axis of the input shaft.

[0009] According to the transmission mechanism, the second external gear and the first external gear are cycloidal teeth, subcycloidal teeth, or modified cycloidal teeth, and the second internal gear and the first internal gear are arc teeth.

[0010] According to the transmission mechanism, the first internal gear has a first internal tooth, the first external gear has a first external tooth, and the first internal tooth and the first external tooth partially mesh.

[0011] The second internal gear has a second internal tooth, the second external gear has a second external tooth, and the second internal tooth and the second external tooth partially mesh.

[0012] The transmission mechanism of this application has the advantages of being easy to manufacture, having high rigidity, and having small dimensions in the axial direction.

[0013] Other features, advantages, and embodiments of this application may be set forth or become apparent from the following detailed description, accompanying drawings, and claims. Furthermore, it should be understood that the above description and the following detailed description are exemplary and intended to provide further explanation, without limiting the scope of the claimed application. However, the detailed description and specific examples only indicate preferred embodiments of this application. Various changes and modifications within the spirit and scope of this application will become apparent to those skilled in the art through these detailed descriptions. Attached Figure Description

[0014] These and other features and advantages of this application can be better understood by reading the following detailed description with reference to the accompanying drawings, in which the same reference numerals denote the same parts, wherein:

[0015] Figure 1A This is a perspective view of the transmission mechanism according to this application, viewed from front to back;

[0016] Figure 1B yes Figure 1A The transmission mechanism shown is a three-dimensional view viewed from back to front.

[0017] Figure 1C yes Figure 1A A cross-sectional view of the transmission mechanism shown;

[0018] Figure 2A yes Figure 1C A 3D view of the input axis shown;

[0019] Figure 2B yes Figure 2A The side view of the input axis shown;

[0020] Figure 2C yes Figure 2A An enlarged view of the eccentricity of the input shaft is shown.

[0021] Figure 3 yes Figure 1C A perspective view of the first external gear, the connecting disc, and the second external gear shown.

[0022] Figure 4A yes Figure 1C A perspective view of the first external gear shown;

[0023] Figure 4B yes Figure 4A A cross-sectional view of the first external gear shown;

[0024] Figure 5A yes Figure 1C A perspective view of the second external gear shown;

[0025] Figure 5B yes Figure 5A A cross-sectional view of the second external gear shown;

[0026] Figure 6A yes Figure 1C A 3D view of the connecting disk shown;

[0027] Figure 6B yes Figure 6A A cross-sectional view of the connecting disk shown;

[0028] Figure 7 yes Figure 1C A perspective view of the first internal gear shown;

[0029] Figure 8 yes Figure 1C A perspective view of the second internal gear shown;

[0030] Figure 9 yes Figure 1C A 3D view of the output component shown;

[0031] Figure 10 yes Figure 1C A perspective view of the first end cap shown;

[0032] Figure 11 yes Figure 1C A perspective view of the second end cap shown;

[0033] Figure 12 yes Figure 1C A three-dimensional view of the bearing shown;

[0034] Figure 13A yes Figure 1C The axial sectional view of the transmission mechanism shown;

[0035] Figure 13B yes Figure 13A A schematic diagram of the AA section of the transmission mechanism shown;

[0036] Figures 14A-14C The force analysis of the second external gear, the first external gear, and the input shaft is shown respectively;

[0037] Figure 15 This is a cross-sectional view of a second embodiment of the first planetary conversion device and the second planetary conversion device. Detailed Implementation

[0038] Various specific embodiments of this application will now be described with reference to the accompanying drawings, which form part of this specification. It should be understood that although directional terms such as "left," "right," "inner," and "outer," etc., are used in this application to describe various example structural parts and elements of this application, their use is merely for illustrative purposes and is based on the example orientations shown in the drawings. Since the embodiments disclosed in this application can be arranged in different orientations, these directional terms are for illustrative purposes only and should not be considered limiting. In the following drawings, the same reference numerals are used for the same parts.

[0039] Output element Figure 1A-1C The overall structure of a transmission mechanism 100 according to an embodiment of this application is shown, wherein Figure 1A This is a three-dimensional view of the transmission mechanism 100 from front to back. Figure 1B yes Figure 1A The diagram shown is a perspective view of the transmission mechanism 100 viewed from back to front. Figure 1C yes Figure 1A A cross-sectional view of the transmission mechanism 100 shown. (As shown) Figure 1A-1C As shown, the transmission mechanism 100 includes an input shaft 106, a first internal gear 102, a second internal gear 108, a connecting disc 114, a first external gear 116, a second external gear 112, an output element 109, a first end cover 104, and a second end cover 103. The first external gear 116, the connecting disc 114, and the second external gear 112 are mounted side-by-side on the input shaft 106, with the connecting disc 114 located between the first external gear 116 and the second external gear 112. The first internal gear 102, the first end cover 104, and the second end cover 103 are fixedly connected, and the second internal gear 108 and the output element 109 are fixedly connected. The first internal gear 102 meshes with the first external gear 116, and the second internal gear 108 meshes with the second external gear 112. The transmission mechanism 100 also includes a first planetary converter and a second planetary converter. The first planetary converter connects the connecting disc 114 to the first external gear 116, and the second planetary converter connects the connecting disc 114 to the second external gear 112. The input shaft 106 serves as a power input component (i.e., connected to the drive component). The connected first internal gear 102, first end cover 104, and second end cover 103 are connected to the fixed side (i.e., fixed), and the connected second internal gear 108 and output element 109 are connected to the load side. Through the connecting disc 114, the first planetary converter, and the second planetary converter, the first external gear 116 and the second external gear 112 can perform planetary motion and drive the second internal gear 108 and output element 109 to rotate, thereby rotating the load.

[0040] Figure 2A-2C It shows Figure 1C The specific structure of the input shaft 106 shown is as follows: Figure 2A This is a 3D view of input axis 106. Figure 2B This is a side view of input axis 106. Figure 2C This is an enlarged view of the eccentricity of input shaft 106. For example... Figure 2A-2C As shown, the input shaft 106 includes an input shaft body, which is generally cylindrical, and has an input shaft central axis X1. A drive mechanism is capable of driving the input shaft 106 to rotate about its input shaft central axis X1. As an example, the drive mechanism is a motor.

[0041] The input shaft body has a first eccentric portion 212 and a second eccentric portion 214 with the same eccentric direction. The first eccentric portion 212 is generally an annular ring eccentrically positioned relative to the input shaft's central axis X1. The outer peripheral surface 252 of the first eccentric portion 212 forms a circular surface with radius D1. The outer peripheral surface 252 has a central axis N1. The distance between the central axis N1 and the input shaft's central axis X1 is a first eccentricity d1. The second eccentric portion 214 is generally an annular ring eccentrically positioned relative to the input shaft's central axis X1 of the input shaft 106. The outer peripheral surface 254 of the second eccentric portion 214 forms a circular surface with radius D2. The outer peripheral surface 254 has a central axis N2. The distance between the central axis N2 and the input shaft's central axis X1 is a second eccentricity d2. Wherein, d1 ≠ d2. In this application, d1 is less than d2. The central axis N1 of the outer peripheral surface 252 of the first eccentric portion 212 and the central axis N2 of the outer peripheral surface 254 of the second eccentric portion 214 are located in the same plane as the central axis X1 of the input shaft, thus making the first eccentric portion 212 and the second eccentric portion 214 have the same eccentric direction. When the input shaft 106 rotates about its input shaft central axis X1, the central axis N1 of the first eccentric portion 212 and the central axis N2 of the second eccentric portion 214 both rotate about the input shaft central axis X1.

[0042] In addition, the input shaft 106 is provided with an isolation portion 213 located between the first eccentric portion 212 and the second eccentric portion 214, so that the first eccentric portion 212 and the second eccentric portion 214 are spaced apart by a distance in the axial direction. The isolation portion 213 is a non-eccentric portion, its outer peripheral surface is a circumferential surface, and it is coaxial with the input shaft 106.

[0043] Figure 3 yes Figure 1C The perspective view shown depicts the first external gear 116, the connecting disc 114, and the second external gear 112, illustrating a first embodiment of the first and second planetary converter. Figure 3 In this embodiment, the first planetary converter and the second planetary converter are linear bearings, which include structures disposed on the first external gear 116 / second external gear 112 and the connecting disc 114, which will combine Figure 4A-6B Detailed introduction.

[0044] Figure 4A and 4B The specific structure of the first external gear 116 is shown, wherein Figure 4A This is a 3D view of the first external gear 116. Figure 4B This is a sectional view of the first external gear 116. (See image.) Figures 4A-4BAs shown, the first external gear 116 includes a first external gear body 402. The first external gear body 402 is generally annular and has a certain thickness. The first external gear body 402 has a first external gear central axis N1. Its outer periphery has first external teeth 412 for meshing and transmission with the first internal gear 102. Two first protrusions 422 are provided on the left side of the first external gear body 402. The first protrusions 422 are generally cuboid. The two first protrusions 422 are symmetrically arranged on the upper and lower sides of the first external gear central axis N1 and extend axially outward from the left side of the first external gear body 402.

[0045] Figure 5A and 5B The specific structure of the second external gear 112 is shown, wherein Figure 5A This is a 3D view of the second external gear 112. Figure 5B This is a cross-sectional view of the second external gear 112. (As shown...) Figures 5A-5B As shown, the second external gear 112 includes a second external gear body 502. The second external gear body 502 is generally annular and has a certain thickness. The second external gear body 502 has a second external gear central axis N2. Its outer periphery has second external teeth 512 for meshing and transmission with the second internal gear 108. Two second protrusions 522 are provided on the right side of the second external gear body 502. The second protrusions 522 are generally cuboid. The two second protrusions 522 are symmetrically arranged on opposite sides of the second external gear central axis N2 and extend axially outward from the right side of the second external gear body 502.

[0046] Figure 6A and 6B The specific structure of the connecting disk 114 is shown, in which Figure 6A This is a 3D view of the connecting disk 114. Figure 6B This is a cross-sectional view of the connecting disk 114. (Example) Figures 6A-6B As shown, the connecting disc 114 is generally disc-shaped, having a central hole 602 and a central axis X2. The inner wall dimension of the central hole 602 is larger than the outer circumferential dimension of the isolation portion 213 of the input shaft 106, so that when the connecting disc 114 is fitted onto the input shaft 106, the connecting disc 114 does not contact the input shaft 106. The connecting disc 114 is also provided with two first receiving portions 612 and two second receiving portions 614. The shape of the first receiving portion 612 is similar to that of the first protrusion 422, but its size is larger than that of the first protrusion 422. The shape of the second receiving portion 614 is similar to that of the second protrusion 522, but its size is larger than that of the second protrusion 522. Both the first receiving portions 612 and the second receiving portions 614 penetrate the connecting disc 114 along its axial direction. In the circumferential direction, the two first receiving portions 612 and the two second receiving portions 614 are evenly arranged around the central axis X2 of the connecting disc.

[0047] Continue to refer to Figure 3 In a first embodiment, the first planetary converter consists of two sets of first linear bearings, and the second planetary converter consists of two sets of second linear bearings. The two sets of first linear bearings are arranged symmetrically with respect to the central axis X2 of the connecting disk, and the two sets of second linear bearings are also arranged symmetrically with respect to the central axis X2 of the connecting disk. Furthermore, the first and second linear bearings are evenly distributed around the central axis X2 of the connecting disk. Therefore, the first and second linear bearings are arranged at a 90° angle around the central axis X1 of the input shaft (i.e., the central axis of the input shaft 106).

[0048] Specifically, each set of first linear bearings includes a first protrusion 422 disposed on the first external gear 116, a first receiving portion 612 disposed on the connecting disc 114, and two pairs of bearing rollers 601, each pair of bearing rollers 601 including two bearing rollers 601. The second linear bearing includes a second protrusion 522 disposed on the second external gear 112, a second receiving portion 614 disposed on the connecting disc 114, and two pairs of bearing rollers 602, each pair of bearing rollers 602 including two bearing rollers 602. When the transmission mechanism 100 is assembled in place, the first protrusion 422 is inserted into the first receiving portion 612, and the two pairs of bearing rollers 601 are respectively arranged on both sides of the first protrusion 422 in the circumferential direction and are clamped between the first protrusion 422 and the inner wall of the first receiving portion 612 (see [reference]). Figure 13B In the radial direction, the first protrusion 422 is smaller than the first receiving portion 612, thus allowing the first protrusion 422 to move linearly within the first receiving portion 612 radially. This arrangement enables the first external gear 116 to drive the connecting disc 114 to rotate synchronously, while simultaneously allowing the first external gear 116 to move linearly relative to the connecting disc 114. Furthermore, the second protrusion 522 is inserted into the second receiving portion 614, with two pairs of bearing rollers 602 arranged circumferentially on both sides of the second protrusion 522 and clamped between the second protrusion 522 and the inner wall of the second receiving portion 614 (see [link]). Figure 13B In the radial direction, the second protrusion 522 is smaller than the second receiving portion 614, so the second protrusion 522 can move linearly in the second receiving portion 614 radially. The above arrangement allows the connecting disc 114 to drive the second external gear 112 to rotate synchronously, but at the same time allows the second external gear 112 to move linearly relative to the connecting disc 114.

[0049] Figure 7 and Figure 8 A perspective view of the first internal gear 102 and the second internal gear 108 is shown respectively. Figure 7As shown, the first internal gear 102 is generally annular and has a central axis X3. The first internal gear 102 has a hollow portion 712 that extends axially through it. The first internal gear 102 is fitted onto the first external gear 116 through the hollow portion 712. The inner wall of the first internal gear 102 includes a first portion and a second portion along the axial direction. The first portion of the inner wall has first internal teeth 702 for meshing with the first external teeth 412 of the first external gear 116. As an example, the first internal teeth 702 are formed by needle rollers. The inner wall dimension of the second portion of the inner wall is set to be larger than the outer circumference dimension of the connecting disc 114, so that when the connecting disc 114 is accommodated in the first internal gear 102, the connecting disc 114 does not contact the first internal gear 102. Figure 8 As shown, the second internal gear 108 is generally annular and has a central axis X4. The second internal gear 108 has a hollow portion 812 that extends axially through it. The second internal gear 108 is fitted onto the second external gear 112 through the hollow portion 812. The inner wall of the second internal gear 108 has second internal teeth 802 for meshing with the second external teeth 512 of the second external gear 112. As an example, the second internal teeth 802 are formed by needle rollers.

[0050] Figure 9 yes Figure 1C The diagram shows a perspective view of the output element 109. The output element 109 is a flange, generally annular in shape, and has a central axis X5. The output element 109 has a hollow portion 901 extending axially through it to accommodate the input shaft 106. The output element 109 is located on the left side of the second internal gear 108 and is fixedly connected to it. In embodiments of this application, the output element 109 and the second internal gear 108 are connected by bolts.

[0051] Figure 10 and Figure 11 Perspective views of the first end cap 104 and the second end cap 103 are shown respectively. Figure 10 As shown, the first end cap 104 is generally annular and has a central axis X6. The first end cap 104 has a hollow portion 1001 extending axially through it to accommodate the input shaft 106. The first end cap 104 is located on the right side of the first external gear 116 and is fixedly connected to the first internal gear 102. In embodiments of this application, the first end cap 104 and the first internal gear 102 are connected by bolts. Figure 11As shown, the second end cap 103 is generally annular and has a central axis X7. The second end cap 103 has a hollow portion 1012 that extends axially through it. The second end cap 103 is fitted onto the second internal gear 108 through the hollow portion 1012. The second end cap 103 is located on the left side of the first internal gear 102 and is fixedly connected to it. In an embodiment of this application, the second end cap 103 and the first internal gear 102 are connected by bolts.

[0052] Figure 12 yes Figure 1C The diagram shows a perspective view of bearing 110 to illustrate its specific structure. (Reference) Figure 1C In this application, the first internal gear 102, the second end cover 103, and the second internal gear 108 cooperate to form an annular space for mounting the bearing 110. Specifically, inclined portions are provided on the left side of the inner wall of the hollow portion 912 of the first internal gear 102 and the right side of the inner wall of the hollow portion 1012 of the second end cover 103, and a recess is provided on the outer circumferential wall of the second internal gear 108, so that the first internal gear 102, the second end cover 103, and the second internal gear 108, after assembly, form an annular shape with a roughly rectangular cross-section to accommodate the bearing 110. Figure 12 As shown, as an example, bearing 110 is a crossed roller bearing. Specifically, bearing 110 includes forty rollers 1201. Each roller 1201 is a cylinder. The forty rollers 1201 are housed in an annular space and arranged in a ring. As an example, in this embodiment, the axes of two adjacent rollers 1201 are perpendicular to each other. In other words, twenty of the forty rollers 1201 have their axes arranged along a first direction, and the other twenty rollers 1201 have their axes arranged along a second direction, wherein the first direction is perpendicular to the second direction. Furthermore, in this embodiment, the axis of any roller 1201 is inclined to the input shaft center axis X1. Rollers 1201 with axes inclined to the input shaft center axis X1 can withstand axial forces parallel to the input shaft center axis X1.

[0053] Figure 13A and 13B The specific assembly structure of the transmission mechanism 100 is shown, wherein Figure 13A This is an axial sectional view of the transmission mechanism 100. Figure 13B This is a schematic diagram of section AA of the transmission mechanism 100. (See diagram below.) Figures 13A-13BAs shown, when the transmission mechanism 100 is assembled, the input shaft center axis X1, the first internal gear center axis X3, the second internal gear center axis X4, the output element center axis X5, the first end cover center axis X6, and the second end cover center axis X7 are coaxially arranged. The first external gear 116 and the second external gear 112 are respectively sleeved on the first eccentric part 212 and the second eccentric part 214. The connecting disc 114 is sleeved on the isolation part 213, and the first external gear 116 and the second external gear 112 are connected to the connecting disc 114 through the first linear bearing and the second linear bearing, respectively. The first external gear 116 and the first internal gear 102 form a first-stage meshing, and the second external gear 112 and the second internal gear 108 form a second-stage meshing, and the first-stage meshing and the second-stage meshing have different transmission speed ratios.

[0054] When the transmission mechanism 100 drives the load, the input shaft 106 rotates around the central axis X1 of the input shaft under the drive of the drive mechanism (e.g., a motor, not shown), and applies driving force to the first external gear 116 and the second external gear 112 through the first eccentric part 212 and the second eccentric part 214, respectively. Under the drive of the input shaft 106 and constrained by the first planetary converter and the second planetary converter, the first external gear 116 and the second external gear 112 can perform planetary motion, and the first external gear 116 and the second external gear 112 rotate synchronously with the connecting disk 114. More specifically, the first planetary converter causes the first external gear 116 to perform planetary motion under the drive of the input shaft 106, and converts the planetary motion of the first external gear 116 into the rotational motion of the connecting disk 114. The second planetary converter causes the second external gear 112 to perform planetary motion under the drive of the input shaft 106, and causes the second external gear 112 to drive the second internal gear 108 to rotate. The second internal gear 108 thereby drives the output element 109 to rotate, and drives the load to rotate. Furthermore, by setting the speed ratio between the first-stage meshing and the second-stage meshing, the purpose of deceleration can be achieved.

[0055] The transmission mechanism 100 of this application connects the first external gear 116 and the second external gear 112 via a connecting disc 114, a first planetary converter, and a second planetary converter, thereby transmitting torque and speed. Therefore, the transmission mechanism 100 of this application does not require multiple pins and bushings penetrating the external gears to connect the dual-sided output elements and the speed and torque of the output external gears. Consequently, the transmission mechanism 100 of this application does not require machining through holes on the external gears for the bushings to pass through, thus reducing machining accuracy requirements and making it easier to manufacture. Furthermore, since the transmission mechanism 100 of this application does not require transmitting speed and torque via slender pins and bushings, it has high rigidity and is suitable for applications requiring high torque output. In addition, the transmission method of the transmission mechanism 100 of this application dictates that it only has a single-sided output element, thus allowing for a smaller axial dimension and a flatter overall shape, making it suitable for increasingly miniaturized applications. Moreover, the reduced number of components in the transmission mechanism 110 of this application simplifies the structure and makes assembly easier.

[0056] Figures 14A-14C The force analysis of the first external gear 116, the second external gear 112, and the input shaft 106 is shown. The following explanation will take the example of the input shaft 106 rotating clockwise and the second internal gear 108 and the output element 109 rotating clockwise:

[0057] When the output element 109 rotates clockwise and is connected to the driven device, the driven device generates a clockwise torque on the output element 109. More specifically, the driven device generates an external torque T about the input shaft central axis X1 and in a clockwise direction on the second internal gear 108 connected to the output element 109.

[0058] Figure 14A A schematic diagram showing the forces acting between the second internal gear 108 and the second external gear 112 is provided. Figure 14A In this context, it is assumed that the line connecting the maximum eccentricity of the outer circumference of the second external gear 112 to its axis is in the Y direction, and the direction perpendicular to the Y direction is in the X direction. When the second external tooth 512 of the second external gear 112 is a cycloidal tooth, a subcycloidal tooth, or a modified cycloidal tooth, and the second internal tooth 802 of the second internal gear 108 is a needle-rolled tooth (i.e., the second internal gear 108 is a circular arc tooth), the force direction of the meshing second external tooth 512 and the second internal tooth 802 points towards the intersection point M2, which is closer to the eccentricity direction, between the two intersection points of the pitch circle and the Y direction. Here, the pitch circle radius R2 = (i2-1) × d2; i2 represents the transmission speed ratio of the second stage meshing, i.e., the transmission speed ratio between the second external gear 112 and the second internal gear 108. d2 is the eccentricity of the second eccentric portion 214.

[0059] Figure 14AIn the second stage of meshing shown, when the external torque T is applied to the second internal gear 108 in a clockwise direction through the output element 109, the resultant force of the meshing forces of the meshing second external tooth 512 and the second internal tooth 802 is F in the X direction (i.e., the transverse direction). x2 The resultant force in the Y direction (i.e., the vertical direction) is F. y2 F x2 Satisfy: F x2 =T / R2.

[0060] In this application, for example, by employing modified cycloidal teeth, the number of engagements between the needle roller and the cycloidal teeth and the position of the engaging teeth can be selectively determined, thereby reducing the resultant force F in the Y direction of the meshing force between the second external tooth 512 and the second internal tooth 802. y2 In this application, in the second stage of meshing, six cycloidal teeth are selected to mesh with the needle rollers (that is, at any given moment, the six second internal teeth 802 mesh with the second external teeth 512) to achieve the resultant force F in the Y direction. y2 Minimum (i.e., almost zero). This reduces the force on the input bearing between the second external gear 112 and the input shaft 106, increasing bearing life, and also improves the dynamic balance capability of the transmission mechanism 100.

[0061] Figure 14B A force diagram is shown between the first internal gear 102 and the first external gear 116. Since the connecting disc 114, the first external gear 116, and the second external gear 112 rotate synchronously, the first external gear 116 experiences an external torque T of the same magnitude but opposite direction as the second external gear 112. When the first external tooth 412 of the first external gear 116 is a cycloidal tooth, a subcycloidal tooth, or a modified cycloidal tooth, and the first internal tooth 702 of the first internal gear 102 is a needle roller tooth (i.e., the first internal gear 102 is a circular arc tooth), the force direction of the meshing first external tooth 412 and the first internal tooth 702 points towards the intersection point M1, which is closer to the eccentric direction, between the two intersection points of the pitch circle and the Y direction. Here, the pitch circle radius R1 = (i1-1) × d1, where i1 represents the first stage of meshing, i.e., the transmission speed ratio between the first internal gear 102 and the first external gear 116. d1 is the eccentricity of the first eccentric portion 212.

[0062] Figure 14B In the first stage of meshing shown, when the external torque T is applied to the first internal gear 102 in a counterclockwise direction, the resultant force of the meshing forces on the first external tooth 412 and the first internal tooth 702 in the X direction (i.e., the transverse direction) is F. x1 The resultant force in the Y direction (i.e., the vertical direction) is F. y1 F x1 Satisfy: F x1 =T / R1.

[0063] In this application, for example, by employing modified cycloidal teeth, the number of engagements between the needle rollers and the cycloidal teeth and the position of the engaging teeth can be selectively determined, thereby reducing the resultant force F of the first-stage engagement force between the needle rollers and the cycloidal teeth in the Y direction. y2 In this application, the first-stage meshing selects twelve cycloidal teeth to mesh with the needle rollers (that is, at any given moment, the twelve first internal teeth 702 mesh with the first external teeth 412) to achieve the resultant force F in the Y direction. y1 Minimum (i.e., almost zero). This reduces the force on the input bearing between the first external gear 116 and the input shaft 106, increasing bearing life, and also improves the dynamic balance capability of the transmission mechanism 100.

[0064] Figure 14C This describes the force state of the input shaft 106 when the first and second stages of meshing act simultaneously. As mentioned above, by selecting the number of engagements between the needle rollers and the cycloidal teeth and the position of the meshing teeth, the resultant force F in the Y direction can be made... y1 and F y2 The values ​​are approximately equal to zero, thus enabling the transmission mechanism 100 to achieve dynamic balance in the Y direction.

[0065] Furthermore, when the first eccentricity d1 and the second eccentricity d2 satisfy: At that time, F x1 and F x2 Their sizes are approximately equal, and since F x1 and F x2 The directions are opposite, thus making the resultant force F in the X direction... x Approximately equal to zero, thus achieving dynamic balance of the transmission mechanism 100 in the X direction. Wherein... n1 is the number of teeth of the first external gear 116, n2 is the number of teeth of the first internal gear 102, n3 is the number of teeth of the second external gear 112, and n4 is the number of teeth of the second internal gear 108.

[0066] For example, as an embodiment, the first eccentricity d1 and the second eccentricity d2 satisfy the following conditions:

[0067]

[0068] Through the above configuration, the transmission mechanism of this application can achieve dynamic balance, thus meeting the needs of applications with high dynamic balance requirements (such as high-precision robots). The transmission mechanism of this application is also suitable for applications with lower dynamic balance requirements, such as walking robots. Therefore, the transmission mechanism of this application has a wide range of applications.

[0069] Figure 15This is a cross-sectional view of a second embodiment of the first and second planetary converters. The first planetary converter is a first linear slider, and the second planetary converter is a second linear slider. Figure 15 As shown, the first linear slider includes two first protrusions 1504 on the first external gear 116 and two first receiving portions 1502 on the connecting disk 114. The second linear slider includes two second protrusions 1506 on the second external gear 112 and two second receiving portions 1508 on the connecting disk 114. The similarity between the structure and fit of the protrusions and receiving portions in the linear slider of the second embodiment and the structure and fit of the protrusions and receiving portions in the linear bearing of the first embodiment will not be repeated here. The difference between the linear slider of the second embodiment and the linear bearing of the first embodiment is that neither the first nor the second linear slider includes bearing rollers.

[0070] It should be noted that, although in the first and second embodiments of the first and second planetary converters shown in this application, the first protrusion is disposed on the first external gear 116, the first receiving portion is disposed on the connecting disk 114, the second protrusion is disposed on the second external gear 112, and the second receiving portion is disposed on the first external gear 116, in other embodiments, the first protrusion may be disposed on the connecting disk 114 and the first receiving portion may be disposed on the first external gear 116 and / or the second protrusion may be disposed on the connecting disk 114 and the second receiving portion may be disposed on the second external gear 112.

[0071] It should be understood that the first planetary converter and the second planetary converter in this application are not limited to linear bearings and linear sliders. It should also be understood that although a protrusion extending outward from the first external gear 116, the connecting disc 114, and / or the second external gear 112 is shown in this application, in other embodiments, the protrusion may also be provided on the second external gear 112, the connecting disc 114, and / or the first external gear 116 by means of connection.

[0072] It should also be understood that the first planetary converter and the second planetary converter in this application each include two sets of linear bearings or two sets of linear sliders, but in other embodiments, at least one set of linear bearings and / or linear sliders are within the protection scope of this application.

[0073] It should be noted that this application illustrates a simple reduction mechanism achieved through first-stage and second-stage meshing. Building upon this, in other embodiments, those skilled in the art can add at least one stage of transmission (e.g., planetary transmission) to the transmission mechanism 100 to reduce the rotational speed of the input shaft, thereby reducing friction and temperature rise. Although embodiments involving adding at least one stage of transmission are not shown in this application, all designs employing at least one additional stage are within the scope of protection of this application.

[0074] Although this disclosure has been described in conjunction with examples of the embodiments outlined above, various alternatives, modifications, variations, improvements, and / or substantially equivalents, whether known or currently or soon to be foreseen, will likely be apparent to those skilled in the art. Furthermore, the technical effects and / or technical problems described herein are exemplary and not limiting; therefore, the disclosures herein may be used to solve other technical problems and have other technical effects and / or can solve other technical problems. Accordingly, the examples of embodiments of this disclosure as set forth above are intended to be illustrative and not limiting. Various changes may be made without departing from the spirit or scope of this disclosure. Therefore, this disclosure is intended to include all known or previously developed alternatives, modifications, variations, improvements, and / or substantially equivalents.

Claims

1. A transmission mechanism (100), characterized in that... include: The input shaft (106) is provided with a first eccentric part (212) and a second eccentric part (214) with the same eccentric direction but different eccentricity. An output element (109) is rotatably disposed; A first internal gear (102) and a second internal gear (108), wherein the first internal gear (102) is connected to the fixed side and the second internal gear (108) is connected to the output element (109); The first external gear (116) and the second external gear (112) are respectively sleeved on the first eccentric part (212) and the second eccentric part (214), and respectively mesh with the first internal gear (102) and the second internal gear (108); A connecting disk (114) is disposed between the first external gear (116) and the second external gear (112); The first planetary conversion device connects the first external gear (116) and the connecting disk (114), and is configured to enable the first external gear (116) to perform planetary motion under the drive of the input shaft (106) and convert the planetary motion of the first external gear (116) into the rotational motion of the connecting disk (114). as well as The second planetary converter connects the connecting disk (114) and the second external gear (112) and is configured to enable the second external gear (112) to drive the second internal gear (108) to rotate under the drive of the input shaft (106).

2. The transmission mechanism (100) according to claim 1, characterized in that: The first eccentric part (212) has a first eccentricity d1, and the second eccentric part (214) has a second eccentricity d2. The first eccentricity d1 and the second eccentricity d2 satisfy the following conditions: in, n1 is the number of teeth of the first external gear (116), and n2 is the number of teeth of the first internal gear (102). n3 is the number of teeth of the second external gear (112), and n4 is the number of teeth of the second internal gear (108).

3. The transmission mechanism (100) according to claim 2, characterized in that: The first eccentricity d1 and the second eccentricity d2 satisfy the following conditions:

4. The transmission mechanism (100) according to claim 1, characterized in that: The first external gear (116) and the first internal gear (102) form a first-stage meshing, and the second external gear (112) and the second internal gear (108) form a second-stage meshing. The first-stage meshing and the second-stage meshing have different transmission speed ratios.

5. The transmission mechanism (100) according to claim 1, characterized in that: The first planetary converter is configured to cause the first external gear (116) to drive the connecting disk (114) to rotate synchronously, and to allow the first external gear (116) to move linearly relative to the connecting disk (114); and The second planetary converter is configured to cause the connecting disk (114) to drive the second external gear (112) to rotate synchronously, and to allow the second external gear (112) to move linearly relative to the connecting disk (114).

6. The transmission mechanism (100) according to claim 5, characterized in that: The first planetary converter is a first linear bearing or a first linear slider with a structure disposed on the first external gear (116) and the connecting disk (114). The second planetary converter is a second linear bearing or a second linear slider with a structure disposed on the second external gear (112) and the connecting disk (114). The second linear bearing or the second linear slider is arranged at 90° with the first linear bearing or the first linear slider around the central axis of the input shaft (106).

7. The transmission mechanism (100) according to claim 1, characterized in that: The second external gear (112) and the first external gear (116) are cycloidal teeth, subcycloidal teeth or modified cycloidal teeth, and the second internal gear (108) and the first internal gear (102) are arc teeth.

8. The transmission mechanism (100) according to claim 1, characterized in that: The first internal gear (102) has a first internal tooth (702), and the first external gear (116) has a first external tooth (512). The first internal tooth (702) and the first external tooth (512) are partially meshed. The second internal gear (108) has a second internal tooth (802), and the second external gear (112) has a second external tooth (412). The second internal tooth (802) and the second external tooth (412) are partially meshed.

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