A cycloidal wheel structure, an RV reducer, and an industrial robot

Abstract

This invention provides a cycloidal wheel structure, an RV reducer, and an industrial robot. The cycloidal wheel structure includes a cycloidal wheel and a support column through-hole disposed on the cycloidal wheel. The cycloidal wheel structure also includes a centrifugal oil guiding structure. This centrifugal oil guiding structure guides lubricating oil from the support column through-hole to the tooth profile of the cycloidal wheel when the cycloidal wheel rotates, allowing the lubricating oil to flow freely within the centrifugal oil guiding structure under centrifugal force. According to the technical solution of this invention, when the cycloidal wheel rotates, the lubricating oil in the support column through-hole can move along the centrifugal oil guiding structure to the tooth profile of the cycloidal wheel under the action of centrifugal force, thereby increasing the oil supply between the cycloidal wheel and the pin tooth housing, improving lubrication between the cycloidal wheel and the pin tooth housing, and reducing wear.

Description

Technical Field

[0001] This invention belongs to the field of speed reducer technology, specifically relating to a cycloidal wheel structure, an RV speed reducer, and an industrial robot. Background Technology

[0002] With the transformation and upgrading of intelligent manufacturing, higher precision and reliability requirements are being placed on the high-precision transmission of RV reducers for industrial robots. RV reducers are one of the core components of robot transmission. Compared with other reduction methods, RV reducers have advantages such as large reduction ratio, coaxial transmission, high transmission accuracy, high rigidity, high load capacity, and compact structure, and are widely used in aerospace, robotics, and other industries. The RV reducer for robots has a complex structure. Its first-stage reduction is a spur gear reduction mechanism that reduces speed according to the tooth ratio, and the second-stage reduction is a cycloidal gear reduction mechanism that reduces speed according to the difference in the number of teeth, for a total of two stages of reduction.

[0003] The RV reducer consists of a cycloidal wheel, needle gear housing, needle rollers, crankshaft shaft system assembly, planetary carrier, rigid disc, etc. Among them, the cycloidal wheel is the core connecting and meshing part of the RV reducer, which connects and supports the crankshaft shaft system assembly and directly meshes with the needle rollers to form a second-stage reduction transmission with a small tooth difference.

[0004] In existing technical solutions, due to the meshing characteristics of the cycloidal wheel, the cycloidal teeth of the cycloidal wheel form line contact (small area surface contact) with the needle roller. During meshing, stress concentration occurs between the needle roller and the cycloidal wheel, which easily causes wear on the cycloidal wheel. Furthermore, because the gap between the tooth root of the cycloidal wheel and the needle roller is too small, insufficient lubrication between the cycloidal wheel and the needle tooth housing is easily generated, or even dry friction occurs, leading to abnormal wear of the cycloidal wheel and the needle roller.

[0005] Furthermore, since RV reducers are used in medium and heavy load applications, the meshing stress concentration between the cycloidal wheel and the needle roller is aggravated, which further causes passive extrusion and uneven distribution of lubricating grease, and even dry friction. This leads to rapid wear of the needle roller and needle tooth housing, resulting in abnormal starting conditions and noise, and reducing the accuracy and service life of the RV reducer. Summary of the Invention

[0006] Therefore, the present invention provides a cycloidal wheel structure, an RV reducer, and an industrial robot. The main technical problem to be solved is: how to improve the lubrication between the cycloidal wheel and the pin tooth housing and reduce wear.

[0007] To address the above problems, the present invention provides a cycloidal wheel structure, including a cycloidal wheel and a support column through hole disposed on the cycloidal wheel; the cycloidal wheel structure further includes a centrifugal oil guiding structure.

[0008] The centrifugal oil guiding structure is used to guide the lubricating oil in the support column through hole to the tooth profile of the cycloidal wheel when the cycloidal wheel rotates, and to allow the lubricating oil to flow by itself within the centrifugal oil guiding structure under the action of centrifugal force.

[0009] In some embodiments, the centrifugal oil guiding structure includes a centrifugal oil hole disposed on the cycloidal wheel, through which the centrifugal oil guiding structure guides the lubricating oil in the support column through hole to the tooth profile of the cycloidal wheel when the cycloidal wheel rotates.

[0010] In some embodiments, the centrifugal oil hole extends radially along the cycloidal wheel;

[0011] And / or, the end of the centrifugal oil hole away from the support column through hole is located at the root of the cycloidal wheel teeth.

[0012] In some embodiments, the diameter d1 of the centrifugal oil hole satisfies:

[0013] When π*d / Z*(1-n1)*n2<H*A, π*d / Z*(1-n1)*n2≤d1<H*A

[0014] When π*d / Z*(1-n1)*n2≥H*A, d1=H*A

[0015] Where d is the root circle diameter of the cycloidal wheel; Z is the number of cycloidal teeth of the cycloidal wheel; n1 is the ratio of the area of ​​the first region to the area of ​​the cycloidal tooth profile of the cycloidal wheel, the first region being the area where the cycloidal tooth profile of the cycloidal wheel contacts the needle roller during the entire meshing process; H is the height of the cycloidal wheel; n2 is the tooth profile occupancy coefficient of the centrifugal oil hole, the value range of n2 is 0.4 to 0.6; A is a constant, the value range of A is 0.2 to 0.3.

[0016] In some embodiments, the cycloidal wheel has an annular groove on its tooth profile, and the annular groove is connected to the centrifugal oil guiding structure.

[0017] In some embodiments, when the centrifugal oil guiding structure includes a centrifugal oil hole disposed on the cycloidal wheel, and the centrifugal oil guiding structure connects the support column through hole and the tooth profile of the cycloidal wheel through the centrifugal oil hole, the end of the centrifugal oil hole facing away from the support column through hole is located in the annular groove of the tooth profile so as to communicate with the annular groove of the tooth profile.

[0018] In some embodiments, the depth m of the tooth profile annular groove satisfies: m≤A1*(Dd); where D is the addendum circle diameter of the cycloidal wheel, d is the dedendum circle diameter of the cycloidal wheel, and A1 is a constant, with a value range of 0.03 to 0.05.

[0019] And / or, the height h1 of the tooth profile annular groove satisfies: when d1 < H*B, d1 ≤ h1 < H*B; when d1 = H*B, h1 = d1; where H is the height of the cycloid gear, d1 is the diameter of the centrifugal oil hole; B is a constant, and the value range of B is 0.2 to 0.3.

[0020] In some embodiments, a tooth root oil storage groove is provided at the tooth root of the cycloid gear.

[0021] In some embodiments, when the centrifugal oil guiding structure includes a centrifugal oil hole provided on the cycloid gear, and the centrifugal oil guiding structure guides the lubricating oil in the support column through hole to the tooth profile of the cycloid gear when the cycloid gear rotates, and one end of the centrifugal oil hole背离 the support column through hole is located in the tooth profile annular groove, one end of the centrifugal oil hole背离 the support column through hole is located inside the tooth root oil storage groove, so as to communicate with the tooth profile annular groove through the tooth root oil storage groove.

[0022] In some embodiments, the height h2 of the tooth root oil storage groove satisfies: h1 < h2 ≤ H*C, where h1 is the height of the tooth profile annular groove; C is a constant, and the value range of C is 0.5 to 0.6. [[ID=eleven]]

[0023] The present invention also provides an RV reducer, which may include the cycloid gear structure of any one of the above.

[0024] The present invention also provides an industrial robot, which may include the RV reducer of any one of the above.

[0025] The cycloid gear structure, RV reducer and industrial robot provided by the present invention have the following beneficial effects:

[0026] [[ID=twenty-one]]1. Through the provided centrifugal oil guiding structure, when the cycloid gear rotates, the lubricating oil in the support column through hole can move along the centrifugal oil guiding structure to the tooth profile of the cycloid gear under the action of centrifugal force, thereby increasing the oil supply amount between the cycloid gear and the pin tooth housing, improving the lubrication between the cycloid gear and the pin tooth housing, and reducing wear.

[0027] 2. By providing a tooth root oil storage groove and a tooth profile annular groove at the cycloid tooth profile of the cycloid gear, the amount of grease at the tooth root is increased, and the grease can form a circulating circuit of grease in the circumferential direction following the tooth profile annular groove, solving the problem in the prior art that the cycloid tooth profile of the cycloid gear forms a line contact (small area surface contact) with the roller pin, stress concentration is formed between the roller pin and the cycloid gear during the meshing process, the lubricating grease is extruded passively, unevenly distributed and cannot circulate smoothly.

[0028] 3. A design scheme of a centrifugal oil hole and a tooth profile annular groove is proposed, which improves the lubrication and cooling effect while ensuring the rigidity of the cycloid-pin meshing. In addition, the operating conditions of the cycloid-pin are optimized, and the service life of the parts and the RV reducer is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of a cycloidal wheel structure provided in one embodiment of the present invention;

[0031] Figure 2 yes Figure 1 Another structural diagram of the cycloidal wheel structure;

[0032] Figure 3 This is a partial structural diagram of an RV reducer;

[0033] Figure 4 This is a schematic diagram of the planetary carrier structure;

[0034] Figure 5 This is an exploded view of the cycloidal pin structure of an RV reducer;

[0035] Figure 6 This is a cross-sectional view of the cycloidal pin structure of the RV reducer.

[0036] The attached figures are labeled as follows:

[0037] 1. Cycloidal wheel; 2. Needle roller; 3. Needle tooth housing; 4. Planetary gear; 5. Main bearing; 6. Planetary carrier; 7. Rigid disc; 8. Eccentric shaft assembly; 9. Snap ring; 10. Support column through hole; 11. Center hole; 12. Eccentric shaft hole; 13. Tooth profile; 61. Support column; 101. Centrifugal oil hole; 102. Tooth profile annular groove; 103. Tooth root oil reservoir. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0040] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0041] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the structures, proportions, sizes, etc., shown in the accompanying drawings are only for the purpose of illustrative purposes and to facilitate understanding and reading by those skilled in the art, and are not intended to limit the conditions under which the invention can be implemented. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effects and objectives achieved by the invention, should still fall within the scope of the technical content disclosed in the invention. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0042] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0043] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0044] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0045] See also Figure 1 and Figure 2 As shown, according to an embodiment of the present invention, a cycloidal wheel structure is provided, including a cycloidal wheel 1 and a support column through hole 10 disposed on the cycloidal wheel 1. The support column through hole 10 is used for the support column 61 of the RV reducer to pass through, the support column 61 is used for fixed connection with the planetary carrier 6, and the cycloidal wheel 1 is used to drive the planetary carrier 6 to rotate via the support column 61 when rotating.

[0046] The aforementioned cycloidal wheel structure also includes a centrifugal oil guiding structure, which is used to guide the lubricating oil in the support column through hole 10 to the tooth profile 13 of the cycloidal wheel 1 when the cycloidal wheel 1 rotates, and to allow the lubricating oil to flow by itself in the centrifugal oil guiding structure under the action of centrifugal force.

[0047] In the above example, when the cycloidal wheel 1 rotates, the lubricating oil in the support column through hole 10 can move along the centrifugal oil guide structure to the tooth profile 13 of the cycloidal wheel 1 under the action of centrifugal force, thereby increasing the oil supply between the cycloidal wheel 1 and the needle tooth housing 3, improving the lubrication between the cycloidal wheel 1 and the needle tooth housing 3, and reducing wear.

[0048] The aforementioned centrifugal oil guiding structure can be a pipe structure such as an oil guiding tube, or it can be a centrifugal oil hole 101 provided on the cycloidal wheel 1. To make the structure of the cycloidal wheel 1 more compact, preferably, as shown below... Figure 1 and Figure 2As shown, the aforementioned centrifugal oil guiding structure includes a centrifugal oil hole 101 provided on the cycloidal wheel 1. The centrifugal oil guiding structure guides the lubricating oil in the support column through hole 10 to the tooth profile 13 of the cycloidal wheel 1 through the centrifugal oil hole 101 when the cycloidal wheel 1 rotates.

[0049] In a specific application example, the aforementioned centrifugal oil hole 101 can extend radially along the cycloidal wheel 1. This design makes the flow direction of the lubricating oil consistent with the direction of the centrifugal force, thereby reducing the obstruction of the centrifugal oil hole 101 to the internal lubricating oil flow and facilitating the flow of lubricating oil inside the centrifugal oil hole 101.

[0050] The end of the aforementioned centrifugal oil hole 101 that is away from the support column through hole 10 can be located at the root of the teeth of the cycloidal wheel 1 to increase the oil supply at the root of the teeth of the cycloidal wheel 1. In addition, compared to setting the end of the centrifugal oil hole 101 away from the support column through hole 10 at other positions on the contour of the cycloidal wheel 1, in this example, by setting the end away from the support column through hole 10 at the root of the teeth of the cycloidal wheel 1, the length of the centrifugal oil hole 101 can be shortened, which facilitates processing.

[0051] In a specific application example, the diameter d1 of the aforementioned centrifugal oil hole 101 satisfies:

[0052] When π*d / Z*(1-n1)*n2<H*A, π*d / Z*(1-n1)*n2≤d1<H*A

[0053] When π*d / Z*(1-n1)*n2≥H*A, d1=H*A

[0054] Wherein, d is the root circle diameter of the cycloidal wheel 1; Z is the number of cycloidal teeth of the cycloidal wheel 1; n1 is the ratio of the area of ​​the first region to the area of ​​the cycloidal tooth profile 13 of the cycloidal wheel 1, the first region being the area where the cycloidal tooth profile 13 of the cycloidal wheel 1 contacts the needle roller 2 during the entire meshing process; n2 is the tooth profile occupancy coefficient of the centrifugal oil hole 101; H is the height of the cycloidal wheel 1; the value range of n2 is 0.4 to 0.6; and A is a constant, the value range of A is 0.2 to 0.3.

[0055] It should be noted that the units for d1, d, and H mentioned above are all millimeters.

[0056] In the above example, for the diameter d1 of the centrifugal oil hole 101, it is necessary to consider the meshing situation at the root of the cycloidal tooth profile 13 to avoid damaging the meshing surface of the cycloidal wheel 1 and the needle roller 2, and also to consider the overall rigidity distribution of the cycloidal wheel 1. By making the diameter d1 of the centrifugal oil hole 101 satisfy the above formula, the rigidity of the needle-cycloidal meshing can be guaranteed while improving the lubrication and cooling effect.

[0057] like Figure 2As shown, the tooth profile 13 of the aforementioned cycloidal wheel 1 may be provided with a tooth profile annular groove 102, which is connected to the centrifugal oil guiding structure.

[0058] In the above example, the lubricating oil can follow the tooth profile annular groove 102 to form a grease circulation loop in the circumference, so as to ensure that the lubricating oil path of the entire tooth profile 13 is unobstructed when the cycloidal wheel 1 is rotating at reduced speed, thereby further improving the lubrication between the cycloidal wheel 1 and the needle tooth housing 3 and reducing wear.

[0059] In order to connect the tooth profile annular groove 102 with the centrifugal oil guiding structure, in a specific application example, when the centrifugal oil guiding structure includes a centrifugal oil hole 101 provided on the cycloidal wheel 1, and the centrifugal oil guiding structure connects the support column through hole 10 and the tooth profile 13 of the cycloidal wheel 1 through the centrifugal oil hole 101, one end of the centrifugal oil hole 101 facing away from the support column through hole 10 is located in the tooth profile annular groove 102 to communicate with the tooth profile annular groove 102.

[0060] The end of the centrifugal oil hole 101 that is away from the through hole 10 of the support column can be located on the bottom surface or the wall of the toothed annular groove 102. Preferably, the end of the centrifugal oil hole 101 that is away from the through hole 10 of the support column can be located on the bottom surface of the toothed annular groove 102 to facilitate processing.

[0061] In a specific application example, the depth m of the tooth profile annular groove 102 satisfies: m≤A1*(Dd); where D is the tip circle diameter of the cycloidal wheel 1, d is the root circle diameter of the cycloidal wheel 1, A1 is a constant, and the value range of A1 is 0.03~0.05; the units of D and d are both millimeters.

[0062] In the above example, by making the depth m of the tooth profile annular groove 102 satisfy the above formula, the rigidity of the pin-pendulum meshing can be guaranteed while improving the lubrication and cooling effect.

[0063] In a specific application example, the height h1 of the aforementioned tooth profile annular groove 102 satisfies the following: when d1 < H*B, d1 ≤ h1 < H*B; when d1 = H*B, h1 = d1; where H is the height of the cycloidal wheel, d1 is the diameter of the centrifugal oil hole, and B is a constant, with a value range of 0.2 to 0.3.

[0064] In the above example, by making the height h1 of the tooth profile annular groove 102 satisfy the above formula, the rigidity of the pin-pendulum meshing can be guaranteed while improving the lubrication and cooling effect.

[0065] It should be noted that the aforementioned tooth profile annular groove 102 has a consistent depth at all points along the circumferential direction of the cycloidal wheel 1. In other words, the bottom profile of the tooth profile annular groove 102 is the profile formed by offsetting the tooth profile 13 of the cycloidal wheel 1 equidistantly from the center of the cycloidal wheel 1 by m. This tooth profile annular groove 102 is a contoured annular groove.

[0066] As Figure 1 and Figure 2 shown, an oil storage groove 103 can be provided at the tooth root of the aforementioned cycloid gear 1, so as to increase the oil storage capacity at the tooth root of the cycloid gear 1, enhance the lubrication and cooling effect of the tooth root, and thus further improve the lubrication between the cycloid gear 1 and the pin gear housing 3 and reduce wear.

[0067] In a specific application example, when the centrifugal oil guiding structure includes a centrifugal oil hole 101 provided on the cycloid gear 1, and the centrifugal oil guiding structure guides the lubricating oil in the support column through hole 10 to the tooth profile 13 of the cycloid gear 1 when the cycloid gear 1 rotates through the centrifugal oil hole 101, and one end of the centrifugal oil hole 101 facing away from the support column through hole 10 is located in the tooth profile annular groove 102, one end of the centrifugal oil hole 101 facing away from the support column through hole 10 can be located inside the tooth root oil storage groove 103, so as to communicate the tooth root oil storage groove 103 with the tooth profile annular groove 102.

[0068] In the above example, the tooth profile annular groove 102 penetrates through the opposite two side surfaces of the tooth root oil storage groove 103 to communicate the tooth profile annular groove 102 with the tooth root oil storage groove 103. The lubricating oil can flow from the centrifugal oil hole 101 to the tooth root oil storage groove 103, and then flow from the tooth root oil storage groove 103 to the tooth profile annular groove 102. The lubricating oil circulates in the tooth profile annular groove 102 to improve the lubrication between the cycloid gear 1 and the pin gear housing 3 and reduce wear.

[0069] In a specific application example, the height h2 of the aforementioned tooth root oil storage groove satisfies: h1 < h2 ≤ H * C, where h1 is the height of the tooth profile annular groove and C is a constant, and the value range of C is 0.5 - 0.6.

[0070] In the above example, by making the height h2 of the tooth root oil storage groove 103 satisfy the above formula, the rigidity of the cycloid-pin engagement can be ensured while improving the lubrication and cooling effect.

[0071] It should be noted here that: the width of the aforementioned tooth root oil storage groove 103 is slightly larger than the diameter d1 of the centrifugal oil hole 101, but does not occupy the contact area between the cycloid tooth profile 13 and the roller needle 2. The depth of the tooth root oil storage groove 103 is slightly shallower than the depth of the tooth profile annular groove 102, so as to ensure the lubrication and cooling effects while enabling the lubricating grease in the tooth root oil storage groove 103 to flow back to the tooth profile annular groove 102 for more sufficient and effective circulation.

[0072] It should be noted here that: the above-mentioned tooth root oil storage grooves 103 are evenly distributed along the circumferential direction of the cycloid gear 1 at the tooth roots of each tooth profile 13 of the cycloid gear 1, with a total of Z places, and the tooth root oil storage grooves 103 are of rectangular cavity structure. In order to fully ensure the effectiveness and symmetry of lubrication and cooling, the tooth root oil storage grooves 103 are symmetric about the height center line of the cycloid gear 1 in the axial direction of the cycloid gear 1.

[0073] Embodiments of the present invention also provide an RV reducer, which may include any of the cycloidal wheel structures described above. Because the RV reducer employs the aforementioned cycloidal wheel structure, when the cycloidal wheel 1 rotates, the lubricating oil within the support column through hole 10 can move along the centrifugal oil guide structure to the tooth profile 13 of the cycloidal wheel 1 under the action of centrifugal force. This increases the oil supply between the cycloidal wheel 1 and the needle tooth housing 3, improves lubrication between them, and reduces wear. Furthermore, while ensuring the meshing rigidity of the cycloidal wheel 1 and the needle roller 2, it improves lubrication and cooling effects, optimizes the operating conditions of the cycloidal wheel 1, and extends the service life of the components and the RV reducer.

[0074] The RV reducer is one of the core components of robot transmission. It consists of a first-stage spur gear transmission and a second-stage differential gear transmission, resulting in a complex structure and high transmission precision. Figures 3 to 6 As shown, the RV reducer of the present invention includes a cycloidal wheel structure, a needle roller 2, a needle tooth housing 3, a planetary gear 4, a main bearing 5, a planetary carrier 6, a rigid disc 7, an eccentric shaft assembly 8, and a retaining ring 9, etc. Figure 1 The diagram shows the structure of the cycloidal wheel 1 of the present invention. The cycloidal wheel 1 has a support column through hole 10, an eccentric shaft hole 12, and a center hole 11. In a specific application example, the number of support column through holes 10 can be 6, and the number of eccentric shaft holes 12 can be 2. The cycloidal wheel 1 has a tooth profile 13, which meshes with the needle roller 2. To ensure smooth meshing, the root of the tooth profile 13 usually does not mesh with the needle roller 2. The needle roller 2 is installed in the needle tooth hole of the needle tooth housing 3. The number of cycloidal teeth Z of the cycloidal wheel 1 is 1 less than the number of needle tooth holes of the needle tooth housing 3, forming a differential tooth meshing transmission. The eccentric shaft assembly 8 is installed in the eccentric shaft hole 12 of the cycloidal wheel 1. After the eccentric shaft assembly 8 drives the cycloidal wheel 1 to rotate eccentrically through a first-stage spur gear transmission, the tooth profile 13 of the cycloidal wheel 1 meshes with the needle roller 2 to form a small tooth difference transmission. To ensure the stability of the transmission, the cycloidal wheels 1 are usually used in pairs (two pieces). The planetary carrier 6 and the rigid disk 7 are fixedly connected by six support columns 61, for example, by bolts. The six support columns 61 of the planetary carrier 6 pass through the six support column through holes 10 of the cycloidal wheel 1, and the eccentric oscillating motion of the cycloidal wheel 1 causes the support columns 61 to rotate relative to each other in the support column through holes 10 of the cycloidal wheel 1. The cycloidal wheel 1 is both eccentrically oscillating and rotating along the cycloidal line.

[0075] Embodiments of the present invention also provide an industrial robot, which may include any of the above-described RV reducers. In this example, because the industrial robot uses the above-described RV reducer, when the cycloidal wheel 1 rotates, the lubricating oil in the support column through hole 10 can move along the centrifugal oil guide structure to the tooth profile 13 of the cycloidal wheel 1 under the action of centrifugal force, thereby increasing the oil supply between the cycloidal wheel 1 and the needle tooth housing 3, improving the lubrication between the cycloidal wheel 1 and the needle tooth housing 3, and reducing wear.

[0076] For ease of understanding, the overall structure of the present invention will be described below, and its working principle will be explained.

[0077] like Figure 1 and Figure 2 As shown, this invention optimizes the structure of the cycloidal wheel 1 by incorporating a centrifugal oil hole 101, a tooth root oil reservoir 103, and a tooth profile annular groove 102. The centrifugal oil hole 101 is located at the support column through-hole 10. Lubricating grease in the cavity formed by the support column through-hole 10 of the cycloidal wheel 1 and the support column 61 of the planetary carrier 6 is guided through the centrifugal oil hole 101 to the tooth profile 13 of the cycloidal wheel 1 under centrifugal force, forming a centrifugal grease passage. A tooth-shaped annular groove 102 is provided circumferentially in the middle of the tooth profile 13 of the cycloidal wheel 1, realizing a lubrication channel for the entire tooth profile 13. A tooth root oil reservoir 103 is provided at the tooth root of the cycloidal wheel 1 to increase the lubrication and cooling effect at the tooth root.

[0078] Centrifugal oil hole 101 starts at the support column through hole 10 and ends at the tooth root of cycloidal wheel 1. The center line of centrifugal oil hole 101 passes through the center of the center hole 11 of cycloidal wheel 1 and is located in the middle of cycloidal wheel 1 in the height direction. Specifically, according to the structural characteristics of the tooth profile 13 of cycloidal wheel 1, a total of Z center lines are drawn from the center of cycloidal wheel 1 to each tooth root (Z is the number of cycloidal teeth of cycloidal wheel 1. In a specific application example, the number of cycloidal teeth of cycloidal wheel 1 can be 39 teeth). Then, those passing through the eccentric shaft hole 12 are removed, and those not passing through the support column through hole 10 are also removed. As in the embodiment of the present invention, only 22 lines remain.

[0079] A tooth root oil reservoir 103 and a tooth profile annular groove 102 are provided at the cycloidal tooth profile 13 of the cycloidal wheel 1, which increases the amount of grease at the tooth root and allows the grease to form a grease circulation loop in the circumferential direction along with the tooth profile annular groove 102. This solves the problem in the prior art where the cycloidal tooth profile of the cycloidal wheel 1 forms line contact (small area surface contact) with the needle roller 2, and stress concentration occurs between the needle roller 2 and the cycloidal wheel 1 during meshing, resulting in passive extrusion of grease, uneven distribution, and inability to circulate smoothly.

[0080] Furthermore, this invention proposes a design scheme for centrifugal oil holes and annular grooves in the tooth profile, which improves lubrication and cooling effects while ensuring the rigidity of the pinwheel meshing. It also optimizes the operating conditions of the pinwheel, extending the service life of components and the RV reducer.

[0081] It will be readily understood by those skilled in the art that, without conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0082] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the protection scope of the present invention.

Claims

1. A cycloidal wheel structure, comprising a cycloidal wheel (1) and a support post through hole (10) disposed on the cycloidal wheel (1); characterized in that: The cycloidal wheel structure also includes a centrifugal oil guiding structure; The centrifugal oil guiding structure is used to guide the lubricating oil in the support column through hole (10) to the tooth profile (13) of the cycloidal wheel (1) when the cycloidal wheel (1) rotates, and to make the lubricating oil flow by itself in the centrifugal oil guiding structure under the action of centrifugal force. The centrifugal oil guiding structure includes a centrifugal oil hole (101) disposed on the cycloidal wheel (1). The centrifugal oil guiding structure guides the lubricating oil in the support column through hole (10) to the tooth profile (13) of the cycloidal wheel (1) through the centrifugal oil hole (101) when the cycloidal wheel (1) rotates. The centrifugal oil hole (101) extends radially along the cycloidal wheel (1). One end of the centrifugal oil hole (101) away from the support column through hole (10) is located at the tooth root of the cycloidal wheel (1). The cycloidal wheel (1) has an annular groove (102) on its tooth profile (13), which is connected to the centrifugal oil guiding structure. One end of the centrifugal oil hole (101) away from the support column through hole (10) is located inside the annular groove (102) to communicate with it. The cycloidal wheel (1) has a tooth root oil storage groove (103) at its tooth root. One end of the centrifugal oil hole (101) away from the support column through hole (10) is located inside the tooth root oil storage groove (103) to communicate with the annular groove (102) through the tooth root oil storage groove (103). The height h2 of the tooth root oil storage groove (103) satisfies: Where h1 is the height of the tooth profile annular groove (102); C is a constant, with a value range of 0.5 to 0.6; where, The depth m of the tooth profile annular groove (102) satisfies: ; D is the addendum circle diameter of the cycloidal wheel (1), d is the root circle diameter of the cycloidal wheel (1), A1 is a constant, and the value range of A1 is 0.03~0.05; and / or, the height h1 of the tooth profile annular groove (102) satisfies: when hour, ;when hour, Where H is the height of the cycloidal wheel (1), d1 is the diameter of the centrifugal oil hole (101), and B is a constant with a value range of 0.2 to 0.

3.

2. The cycloidal wheel structure according to claim 1, characterized in that: The diameter d1 of the centrifugal oil hole (101) satisfies: when hour, ; when hour, ; Wherein, d is the root circle diameter of the cycloidal wheel (1); Z is the number of cycloidal teeth of the cycloidal wheel (1); n1 is the ratio of the area of ​​the first region to the area of ​​the cycloidal tooth profile (13) of the cycloidal wheel (1), the first region being the area where the cycloidal tooth profile (13) of the cycloidal wheel (1) contacts the needle roller (2) during the entire meshing process; H is the height of the cycloidal wheel (1); n2 is the tooth profile occupancy coefficient of the centrifugal oil hole (101), the value range of n2 is 0.4~0.6; A is a constant, the value range of A is 0.2~0.

3.

3. An RV reducer, characterized in that: The cycloidal wheel structure includes any one of claims 1-2.

4. An industrial robot, characterized in that: Includes the RV reducer as described in claim 3.

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