Mechanical transmission mechanism

Abstract

The utility model discloses a mechanical transmission mechanism which comprises a planet carrier, at least one planet cylindrical gear, a fixed face gear and a non-fixed face gear, the fixed face gear and the non-fixed face gear are coaxially arranged, and the planet carrier can rotate around the axis of the planet carrier. The planetary cylindrical gear is connected with the planetary carrier; the planetary cylindrical gear deviates from the rotation axis of the planetary carrier; the fixed face gear and the non-fixed face gear are meshed with the planetary cylindrical gear at the same time. The fixed face gear and the non-fixed face gear are different in tooth number, so that a tooth number difference is formed. The transmission ratio is determined by the tooth number of the non-fixed face gear and the tooth number difference between the non-fixed face gear and the fixed face gear, and therefore mechanical transmission with the high transmission ratio can be achieved.

Description

Technical Field

[0001] The utility model relates to a mechanical mechanism, in particular to a mechanical transmission mechanism. Background Art

[0002] As the basic functional unit in the field of mechanical transmission, reducers are widely used. Especially driven by the demand in the fields of industrial robots, service robots and humanoid robots, precision reducers with compact structure, wide speed ratio range and strong load-bearing capacity have formed the current product structure in the joint drive application scenario dominated by RV reducers, harmonic reducers and precision planetary reducers.

[0003] However, the application occasions of these three types of reducers are limited due to their own defects. Among them, the RV reducer has high rigidity but complex structure and manufacturing process and high cost, and is mainly used in occasions that require high load capacity and high impact resistance; the harmonic reducer has a compact structure but low load capacity and service life, and is mainly used in low-load occasions; the precision planetary reducer has high transmission efficiency but low single-stage speed ratio, and is mainly used in high-power transmission occasions.

[0004] Taking robots as an example, due to the limited application scenarios of existing reducers, different joints require different reducers, which leads to high difficulty in product design of the entire robot and a complex supply chain.

[0005] Among the existing reducers, cylindrical and bevel gear reducers need to increase the number of transmission stages to achieve a larger transmission ratio. Due to their large size and weight, they are difficult to use in joint drives that pursue light weight and heavy loads. Planetary reducers can achieve high transmission ratios through complex multi-stage structures, but they are more difficult to design. For example, NW-type planetary reducers require double gears with poor processability. There is also a type of reducer that achieves differential motion through tooth difference. Although it has the characteristics of simple structure and high transmission ratio, it is often only suitable for low-speed occasions due to the eccentric motion of the planetary gear.

[0006] In recent years, a new type of reducer has emerged that achieves a large transmission ratio through tooth difference. For example, Chinese utility model patent document CN115875409A discloses a structure of a planetary gear reducer with a large transmission ratio, a transmission ratio calculation method and a parameter determination method, which specifically discloses a mirror differential planetary gear reducer that achieves a high transmission ratio through two sets of planetary transmissions, but also has problems such as difficult design, use of a double sun gear and complex structure.

[0007] Chinese utility model patent document CN109764108A discloses a hybrid bevel gear differential speed reduction mechanism, which adopts a displacement hybrid bevel gear differential speed reduction method to realize a high transmission ratio reducer based on hybrid bevel gears. However, this mechanism not only has the problems of difficult manufacturing and assembly of hybrid bevel gears and difficulty in ensuring accuracy, but also has a very complex overall structure, which leads to large volume and weight and low accuracy, making it difficult to apply in joint drive.

[0008] Face gears have attracted more and more attention in recent years because they can achieve high-performance transmission and are therefore used in the structure of reducers and transmissions. Japanese utility model patent document JP6420097B2 discloses a face gear reducer, which uses double coaxial face gears to mesh with different cylindrical gears to achieve a single-stage reduction and speed change with an axis angle. However, since it only has one-stage speed change, the transmission ratio is limited by the size of the face gears and is not large enough. Japanese utility model patent document JP6484014B2 discloses a multi-stage gear reducer, which uses face gears as the first stage of multi-stage transmission, which is only a conventional application of face gear transmission. Chinese utility model patent document CN104633022B discloses a planetary multi-stage speed transmission method and device, which uses multiple coaxial face gears to mesh with planetary cylindrical gears at the same time to achieve speed transmission. Since each face gear is a single-stage transmission, the achievable transmission ratio is also limited by the size of the face gears and is only used as a transmission.

[0009] Chinese utility model patent document CN112503143B discloses a displaced hybrid bevel gear differential reduction method, which uses two opposed non-coaxial face gears with unequal numbers of teeth to mesh with a cylindrical gear, and then uses an internally meshing cylindrical gear to compensate for the eccentricity of the axes of the two face gears, and finally realizes tooth difference transmission through a bevel gear differential device. It has a complex structure, is difficult to design and manufacture, and is difficult to control cost, weight, and accuracy. It is also not suitable for use in joint drives.

[0010] In summary, there is currently a lack of a large transmission ratio reducer that can adapt to all joints of the robot. Utility Model Content

[0011] The technical problem to be solved by the utility model is to provide a mechanical transmission mechanism, which can achieve a wide range of transmission ratios, thereby adapting to the application requirements of all joints of the robot.

[0012] In order to solve the above technical problems, the technical solution of the mechanical transmission mechanism of the utility model is:

[0013] The invention comprises a planet carrier, at least one planetary cylindrical gear, and a coaxially arranged fixed face gear and a non-fixed face gear, wherein the planet carrier can rotate around its axis; the planetary cylindrical gear is connected to the planet carrier; the planetary cylindrical gear deviates from the axis of the planet carrier; the fixed face gear and the non-fixed face gear are meshed with the planetary cylindrical gear at the same time; the fixed face gear and the non-fixed face gear have different numbers of teeth, thereby forming a difference in the number of teeth.

[0014] In another embodiment, the planet carrier is fixedly connected to the input shaft, and the input shaft can drive the planet carrier to rotate around its rotation axis; the non-fixed face gear is fixedly connected to the output shaft;

[0015] In another embodiment, the non-fixed face gear is fixedly connected to the input shaft, and the input shaft can drive the non-fixed face gear to rotate around its rotation axis; and the planet carrier is fixedly connected to the output shaft.

[0016] In another embodiment, there are more than two planetary cylindrical gears; and the planetary cylindrical gears are evenly distributed along the circumference of the planet carrier.

[0017] In another embodiment, the diameters of the fixed face gear and the non-fixed face gear are larger than the diameter of the planet carrier, and the fixed face gear, the non-fixed face gear and the planetary cylindrical gear are all arranged outside the planet carrier;

[0018] In another embodiment, the diameters of the fixed face gear and the non-fixed face gear are smaller than the diameter of the planet carrier, and the fixed face gear, the non-fixed face gear and the planetary cylindrical gear are all disposed in the inner cavity of the planet carrier.

[0019] In another embodiment, the number of teeth of the fixed face gear is greater than the number of teeth of the non-fixed face gear; or, the number of teeth of the fixed face gear is less than the number of teeth of the non-fixed face gear.

[0020] In another embodiment, the fixed face gear is disposed on the radial outer side of the non-fixed face gear; or, the fixed face gear is disposed on the radial inner side of the non-fixed face gear.

[0021] In another embodiment, the rotation axes of the fixed face gear and the non-fixed face gear are colinear with the rotation axis of the planet carrier.

[0022] In another embodiment, the number of the planetary cylindrical gears is not greater than the tooth difference between the fixed face gear and the non-fixed face gear.

[0023] In another embodiment, the axial direction of the planetary spur gear extends along the radial direction of the planet carrier.

[0024] In another embodiment, the fixed face gear and the non-fixed face gear mesh with the planetary cylindrical gear at the same shaft angle.

[0025] In another embodiment, the planet carrier is a hollow structure.

[0026] In another embodiment, each time the planetary cylindrical gear rolls one circle on the tooth surface of the fixed face gear, it drives the non-fixed face gear and the output shaft to rotate through an angle; the angle is the angle corresponding to the number of consecutive teeth on the non-fixed face gear that is equal to the difference in the number of teeth between the non-fixed face gear and the fixed face gear.

[0027] In another embodiment, the planet carrier is fixedly connected to the input shaft, and the non-fixed face gear is fixedly connected to the output shaft; the transmission ratio between the input shaft and the output shaft is i HO for:

[0028]

[0029] Among them, n H is the rotation speed of the planet carrier, that is, the rotation speed of the input shaft;

[0030] n O is the speed of the non-fixed face gear, that is, the speed of the output shaft;

[0031] Z O is the number of teeth of the non-fixed face gear;

[0032] Z S is the number of teeth on the fixed face gear.

[0033] In another embodiment, the non-fixed face gear is fixedly connected to the input shaft, and the planet carrier is fixedly connected to the output shaft; the transmission ratio between the input shaft and the output shaft is i IH for:

[0034]

[0035] Among them, n H is the speed of the planet carrier, that is, the speed of the output shaft;

[0036] n I is the speed of the non-fixed face gear, that is, the speed of the input shaft;

[0037] Z I is the number of teeth of the non-fixed face gear;

[0038] Z S is the number of teeth on the fixed face gear.

[0039] The technical effects that can be achieved by the utility model are:

[0040] The transmission ratio of the utility model is determined by the number of teeth of the non-fixed face gear and the difference in the number of teeth between the non-fixed face gear and the fixed face gear, so that mechanical transmission with a high transmission ratio can be achieved.

[0041] The utility model uses ordinary cylindrical gears as planetary gears, and simultaneously meshes with two coaxially arranged face gears with different numbers of teeth with the planetary gears, and realizes deceleration by tooth difference transmission. The utility model not only retains all the advantages of face gear transmission, but also has a simple structure, is easy to design, manufacture and assemble, and is easy to realize a precision reducer product with high precision, high load-bearing capacity and long life, and is particularly suitable for robot joint drive.

[0042] The utility model utilizes two face gears with a difference in the number of teeth. The fixed face gear planetary cylindrical gear can realize self-rotation while revolving. The planetary cylindrical gear can generate driving force on the meshing tooth surface of the non-fixed face gear during the planetary motion process of revolution and rotation, thereby realizing the transmission of force and torque, and driving the non-fixed face gear and the shaft output shaft connected thereto to rotate.

[0043] The utility model can be used as a speed reduction device. The transmission ratio of the utility model is determined by the number of teeth of the non-fixed face gear and the difference in the number of teeth between the non-fixed face gear and the fixed face gear. Compared with the existing speed reducer, the transmission ratio of the utility model has nothing to do with the planetary cylindrical gear, so the appropriate speed reduction ratio can be arbitrarily determined under the condition of the same outer ring face gear size. Of course, the utility model can also be used as a speed increasing device.

[0044] The utility model can be used as a precision reducer, using face gear transmission, with high freedom of design of parameters such as the number of teeth, high transmission efficiency, and high cost performance, and can be applied to the fields of robot joint drive, intelligent equipment, etc. Since face gear transmission is a new type of intersecting axis transmission method in which an involute cylindrical gear meshes with a face gear, compared with conventional bevel gear transmission, the transmission system using face gears has many advantages such as small size, light weight, low noise, high load-bearing capacity, high reliability, and long life, and the two face gears with different numbers of teeth can be driven with a tooth difference, so a wide range of transmission ratios can be achieved.

[0045] The utility model can solve the problems of complex structure, difficult process and high cost of RV reducer in the existing precision reducer technology, as well as the problem of limited bearing capacity and life of flexible gears of harmonic reducer, and also solves the problem of small transmission ratio of planetary reducer. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Those skilled in the art should understand that the following description is only to schematically illustrate the principles of the present invention, which can be applied in a variety of ways to achieve many different alternative embodiments. These descriptions are only used to illustrate the general principles of the teaching content of the present invention and are not meant to limit the utility model concepts disclosed herein.

[0047] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present invention and, together with the general description above and the detailed description of the drawings below, are used to explain the principles of the present invention.

[0048] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0049] Figure 1 It is a schematic diagram of the mechanical transmission mechanism of the utility model; its structure is hollow and compact;

[0050] Figure 2 It is an exploded schematic diagram of the utility model;

[0051] Figure 3 It is a schematic diagram of the driving force of the meshing gear teeth of the planetary cylindrical gear of the utility model, and the power transmission is realized by the mutual shearing of the gear teeth; wherein F3 is the force of the meshing gear teeth of the planetary cylindrical gear under the action of the fixed face gear, and F4 is the force of the meshing gear teeth of the planetary cylindrical gear under the action of the non-fixed face gear;

[0052] Figure 4 It is a schematic diagram of the force point and force direction of the gear teeth of the utility model.

[0053] Figure 5 It is a schematic diagram of the mechanism of the first embodiment of the utility model;

[0054] Figure 6 It is a schematic diagram of the mechanism of the second embodiment of the utility model;

[0055] Figure 7 is a schematic diagram of a third embodiment of the utility model;

[0056] Figure 8 is a schematic diagram of a fourth embodiment of the utility model;

[0057] Fig. 9 It is an exploded schematic diagram of the fourth embodiment of the utility model;

[0058] Fig.10 It is a schematic diagram of the mechanism of the fourth embodiment of the utility model;

[0059] Fig.11 It is a schematic diagram of the mechanism of the fifth embodiment of the present utility model.

[0060] Description of reference numerals in the figures:

[0061] 1 is the planet carrier, 2 is the planetary cylindrical gear,

[0062] 3 is a fixed face gear, 4 is a non-fixed face gear,

[0063] 5 is the driving face gear,

[0064] 11 is an input shaft, and 12 is an output shaft. DETAILED DESCRIPTION

[0065] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution of the embodiment of the utility model will be clearly and completely described in conjunction with the drawings of the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the described embodiment of the utility model, all other embodiments obtained by ordinary technicians in the field without creative work belong to the scope of protection of the utility model. Unless otherwise defined, the technical terms or scientific terms used herein should be the common meanings understood by people with ordinary skills in the field to which the utility model belongs. The "first", "second" and similar words used in this article do not indicate any order, quantity or importance, but are only used to distinguish different components. "Including" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0066] like Figure 1 , Figure 2 As shown, the mechanical transmission mechanism of the utility model includes a planet carrier 1, which is fixedly connected to an input shaft 11, and the input shaft 11 can drive the planet carrier 1 to rotate around its rotation axis; the planet carrier 1 is provided with two planet cylindrical gears 2 evenly distributed along the circumferential direction; the axial direction of the planet cylindrical gears 2 extends along the radial direction of the planet carrier 1;

[0067] A fixed face gear 3 and a non-fixed face gear 4 are provided at one axial end of the planet carrier 1; the fixed face gear 3 and the non-fixed face gear 4 are coaxially arranged; and the rotation axis of the fixed face gear 3 and the non-fixed face gear 4 is colinear with the rotation axis of the planet carrier 1;

[0068] The fixed face gear 3 is fixedly arranged;

[0069] The non-fixed face gear 4 is fixedly connected to the output shaft 12; the non-fixed face gear 4 of the utility model means that the face gear 4 is not fixed and can rotate together with the output shaft 12 or the input shaft 11;

[0070] As the first embodiment of the present utility model, Figure 5As shown, the fixed face gear 3 is arranged on the radial outer side of the non-fixed face gear 4, that is, the fixed face gear 3 serves as an outer ring face gear;

[0071] As a second embodiment of the present invention, Figure 6 As shown, the fixed face gear 3 is arranged on the radial inner side of the non-fixed face gear 4, that is, the non-fixed face gear 4 serves as an outer ring face gear;

[0072] The fixed face gear 3 and the non-fixed face gear 4 have different numbers of teeth, thereby forming a difference in the number of teeth;

[0073] The fixed face gear 3 and the non-fixed face gear 4 are simultaneously meshed with all the planetary cylindrical gears 2 uniformly distributed in the circumferential direction.

[0074] In the first embodiment, the number of teeth of the fixed face gear 3 is greater than the number of teeth of the non-fixed face gear 4; of course, the number of teeth of the fixed face gear 3 may be less than the number of teeth of the non-fixed face gear 4;

[0075] In the second embodiment, the number of teeth of the fixed face gear 3 is smaller than that of the non-fixed face gear 4 ; of course, the number of teeth of the fixed face gear 3 may be larger than that of the non-fixed face gear 4 .

[0076] Due to the characteristics of the face gear itself, the inner tooth pitch of the same face gear is smaller than the outer tooth pitch, that is, the tooth pitch of the face gear is not constant. Therefore, although the planetary cylindrical gear 2 is meshed with the fixed face gear 3 and the non-fixed face gear 4 at the same time, the modules of the fixed face gear 3 and the non-fixed face gear 4 can be different. Therefore, when the fixed face gear 3 is used as the outer ring face gear, the number of teeth of the fixed face gear 3 can be greater than the number of teeth of the non-fixed face gear 4, or less than the number of teeth of the non-fixed face gear 4.

[0077] Preferably, the fixed face gear 3 and the non-fixed face gear 4 mesh with the planetary cylindrical gear 2 at the same axis intersection angle; in this embodiment, the axis intersection angles formed by the axis of the planetary cylindrical gear 2 and the axis of the fixed face gear 3 and the non-fixed face gear 4 are 90 degrees respectively;

[0078] Of course, the axis intersection angle can also be other degrees, as long as the planetary cylindrical gear 2 forms a meshing relationship with the fixed face gear 3 and the non-fixed face gear 4 respectively. Figure 7 As shown in the third embodiment of the present invention, the axis of the planetary cylindrical gear 2 and the axes of the fixed face gear 3 and the non-fixed face gear 4 form an axis angle of 45 degrees.

[0079] Preferably, the planet carrier 1 is a hollow structure, so that the planet carrier 1 has an inner cavity;

[0080] In the first and second embodiments, the fixed face gear 3 and the non-fixed face gear 4 as well as the planetary cylindrical gear 2 are all arranged outside the planetary carrier 1;

[0081] Of course, the fixed face gear 3 , the non-fixed face gear 4 and the planetary cylindrical gear 2 can also be arranged in the inner cavity of the planet carrier 1 .

[0082] The mechanical transmission method of the utility model comprises the following steps:

[0083] The input shaft 11 drives the planet carrier 1 to rotate around its rotation axis;

[0084] During the rotation process, the planet carrier 1 drives the planetary cylindrical gear 2 to rotate around the rotation axis of the planet carrier 1, thereby realizing the orbital revolution of the planetary cylindrical gear 2;

[0085] The planetary cylindrical gear 2 is meshed with the fixed face gear 3; during the revolution of the planetary cylindrical gear 2, the fixed face gear 3 causes the planetary cylindrical gear 2 to rotate around its own cylindrical axis, thereby realizing the self-rotation of the planetary cylindrical gear 2;

[0086] The planetary cylindrical gear 2 is meshed with the non-fixed face gear 4 at the same time, and there is a difference in the number of teeth between the non-fixed face gear 4 and the fixed face gear 3; in the process of the planetary cylindrical gear 2 rolling on the tooth surface of the fixed face gear 3 through rotation and revolution, the planetary cylindrical gear 2 drives the non-fixed face gear 4 to rotate around its rotation axis, thereby driving the output shaft 12 to rotate;

[0087] Specifically, every time the planetary cylindrical gear 2 rolls one circle on the tooth surface of the fixed face gear 3, it drives the non-fixed face gear 4 and the output shaft 12 to rotate through an angle; the size of this angle is the angle corresponding to the number of consecutive gear teeth on the non-fixed face gear 4 that is equal to the difference in the number of teeth between the non-fixed face gear 4 and the fixed face gear 3; for example, when the difference in the number of teeth between the non-fixed face gear 4 and the fixed face gear 3 is three, the size of this angle is the center angle corresponding to the gear teeth of three consecutive non-fixed face gears 4.

[0088] According to the Conversion Institutions Act, there are:

[0089]

[0090] Among them, n O is the speed of the non-fixed face gear 4, i.e. the speed of the output shaft 12;

[0091] n H is the rotation speed of the planet carrier 1, that is, the rotation speed of the input shaft 11;

[0092] n S is the speed of the fixed face gear 3; n S =0;

[0093] Z S is the number of teeth of the fixed face gear 3;

[0094] Z O is the number of teeth of the non-fixed face gear 4;

[0095] The transmission ratio i HO for:

[0096]

[0097] Among them, n O is the rotation speed of the non-fixed face gear 4 and the output shaft 12;

[0098] n H is the rotation speed of the planet carrier 1 and the input shaft 11;

[0099] n S is the speed of the fixed face gear 3; n S =0;

[0100] Z S is the number of teeth of the fixed face gear 3;

[0101] Z O is the number of teeth of the non-fixed face gear 4.

[0102] It can be seen from the above formula that the transmission ratio of the present invention depends on the number of teeth of the non-fixed face gear 4 and the difference in the number of teeth between the non-fixed face gear 4 and the fixed face gear 3 , but has nothing to do with the number of teeth of the planetary cylindrical gear 2 .

[0103] The utility model simultaneously meshes two coaxial face gears with a difference in the number of teeth with the cylindrical gears evenly distributed in the circumferential direction, and the reduction mechanism formed by the utility model has the following advantages in addition to being easy to realize a wide transmission ratio range:

[0104] (1) Simple structure and low cost;

[0105] The utility model has few core components and thus a simple structure; the axial float of the cylindrical gear does not affect the transmission of the face gear, and there is no overload problem caused by the cone top overlap error in the bevel gear transmission that can also achieve intersecting axis transmission. No anti-misalignment design is required, so the design and assembly are simple, making it easy to achieve high precision and low cost.

[0106] (2) Compact size;

[0107] The transmission ratio of the utility model is independent of the number of teeth of the planetary cylindrical gear, so the overall size can be made more compact by reducing the number of teeth and size of the planetary cylindrical gear; furthermore, the two coaxial face gears and the circumferentially uniformly distributed planetary cylindrical gears can realize a hollow structure, so that the reducer is in a circular ring shape as a whole, which not only makes the reducer small in size and light in weight, but also facilitates integration and application, such as Figure 1 shown.

[0108] (3) Strong bearing capacity, stable transmission and high efficiency;

[0109] The utility model adopts hardened gear surface transmission, and the gear teeth of the two face gears and the gear teeth of the planetary cylindrical gears are sheared against each other to realize the transmission of force and torque, so there is no need to worry about the tooth root strength, and the bearing capacity of a single gear tooth is strong. Figure 3 As shown in the figure, the overlap between the face gear and the planetary cylindrical gear is high, which can reach more than 2, and the number of teeth meshing at the same time can be further increased by increasing the number of planetary gears, so it is easy to smoothly transmit strong torque;

[0110] like Figure 4 As shown, n11 is the rotation direction of the input shaft 11, n12 is the rotation direction of the output shaft 12, n21 is the rotation direction of the first planetary cylindrical gear, and n22 is the rotation direction of the second planetary cylindrical gear; the first planetary cylindrical gear and the second planetary cylindrical gear have opposite rotation directions; when the input shaft 11 and the output shaft 12 rotate in the same direction, the force direction of each gear meshing point of the transmission mechanism of the utility model is as follows Figure 4 shown.

[0111] Obviously, the rotation directions of the input shaft 11 and the output shaft 12 may also be opposite.

[0112] The utility model relies on the meshing gear teeth of the planetary cylindrical gear 2 to achieve power transmission. The meshing point between the planetary cylindrical gear 2 and the fixed face gear 3 and the meshing point between the planetary cylindrical gear 2 and the non-fixed face gear 4 are two driving points of the transmission respectively. Since the fixed face gear 3 and the non-fixed face gear 4 are close to each other, the driving points of the transmission are close to each other. Since the utility model uses the gear teeth of the planetary cylindrical gear 2 as the power transmission path, the power transmission path is short. The utility model has high transmission efficiency and is suitable for large torque and high power transmission.

[0113] As another application of the utility model, the input shaft and the output shaft can be interchanged, and the utility model can be used as a speed increasing mechanism;

[0114] Another mechanical transmission method of the utility model comprises the following steps:

[0115] The input shaft 11 drives the non-fixed face gear 4 to rotate;

[0116] The non-fixed face gear 4 and the fixed face gear 3 are meshed with the planetary cylindrical gear 2 at the same time, and there is a difference in the number of teeth between the non-fixed face gear 4 and the fixed face gear 3; during the rotation of the non-fixed face gear 4, under the joint action of the non-fixed face gear 4 and the fixed face gear 3, the planetary cylindrical gear 2 meshed with it is driven to realize rotation and revolution at the same time;

[0117] During the orbital revolution of the planetary cylindrical gear 2 , the planetary carrier 1 connected thereto is driven to rotate around the axis of the planetary carrier 1 , thereby driving the output shaft 12 to rotate.

[0118] Specifically, the transmission ratio i between the input shaft 11 and the output shaft 12 is IH for:

[0119]

[0120] Among them, n H is the rotation speed of the planet carrier 1, that is, the rotation speed of the output shaft 12;

[0121] n I is the speed of the non-fixed face gear 4, i.e. the speed of the input shaft 11;

[0122] Z I is the number of teeth of the non-fixed face gear 4;

[0123] Z S is the number of teeth of the fixed face gear 3.

[0124] As the fourth embodiment of the present utility model, Figures 8 to 10 As shown, the mechanical transmission mechanism of the utility model comprises a coaxially arranged driving face gear 5, a fixed face gear 3 and a non-fixed face gear 4; the fixed face gear 3 and the non-fixed face gear 4 are arranged on the same side, and the fixed face gear 3 and the non-fixed face gear 4 are arranged opposite to the driving face gear 5;

[0125] The fixed face gear 3 is fixedly arranged, and the driving face gear 5 is fixedly connected to the input shaft 11;

[0126] The non-fixed face gear 4 is located on the radially outer side of the fixed face gear 3; or, the non-fixed face gear 4 is located on the radially inner side of the fixed face gear 3; the non-fixed face gear 4 is fixedly connected to the output shaft 12;

[0127] The driving face gear 5, the fixed face gear 3 and the non-fixed face gear 4 are simultaneously meshed with two planetary cylindrical gears 2 evenly distributed along the circumferential direction;

[0128] The planetary cylindrical gear 2 is movably connected to the planetary carrier 1; the axial direction of the planetary cylindrical gear 2 extends along the radial direction of the planetary carrier 1; the rotation axis of the fixed face gear 3 and the non-fixed face gear 4 are collinear with the rotation axis of the planetary carrier 1;

[0129] The fixed face gear 3 and the non-fixed face gear 4 have different numbers of teeth, thereby forming a difference in the number of teeth.

[0130] In the fourth embodiment, the fixed face gear 3 is arranged radially outside the non-fixed face gear 4, that is, the fixed face gear 3 serves as an outer ring face gear;

[0131] As the fifth embodiment of the present utility model, Fig.11 As shown, the fixed face gear 3 is arranged on the radial inner side of the non-fixed face gear 4, that is, the non-fixed face gear 4 serves as an outer ring face gear.

[0132] The mechanical transmission method of the utility model comprises the following steps:

[0133] The planetary cylindrical gear 2 is meshed with the driving face gear 5 and the fixed face gear 3 at the same time, and the planetary cylindrical gear 2 is arranged between the driving face gear 5 and the fixed face gear 3;

[0134] The input shaft 11 drives the driving face gear 5 to rotate around its rotation axis; during the rotation process, the driving face gear 5 drives the planetary cylindrical gear 2 meshing with it to rotate around its rotation axis;

[0135] During the rotation of the planetary cylindrical gear 2, the fixed face gear 3 makes the planetary cylindrical gear 2 and the planet carrier 1 connected thereto rotate around the rotation axis of the planet carrier 1, so as to realize the revolution of the planetary cylindrical gear 2, thereby realizing the first stage of speed reduction from the input shaft 11 to the planet carrier 1;

[0136] According to the Conversion Institutions Act, there are:

[0137]

[0138] Among them, n I is the speed of the driving face gear 5, i.e. the speed of the input shaft 11;

[0139] n H is the speed of planet carrier 1;

[0140] n S is the speed of the fixed face gear 3; n S =0;

[0141] Z S is the number of teeth of the fixed face gear 3;

[0142] Z I is the number of teeth on the active face gear;

[0143] The transmission ratio i of the first stage reduction (i.e. the speed ratio of the input shaft 11 to the planet carrier 1) is IH for:

[0144]

[0145] Among them, n I is the speed of the driving face gear 5, i.e. the speed of the input shaft 11;

[0146] n H is the rotation speed of the planet carrier 1, that is, the revolution speed of the planetary cylindrical gear 2;

[0147] ZS is the number of teeth of the fixed face gear 3;

[0148] Z I is the number of teeth on the active face gear;

[0149] The planetary cylindrical gear 2 is meshed with the non-fixed face gear 4 at the same time, and there is a difference in the number of teeth between the non-fixed face gear 4 and the fixed face gear 3; in the process of the planetary cylindrical gear 2 rotating and revolving at the same time, the planetary cylindrical gear 2 drives the non-fixed face gear 4 to rotate around its rotation axis, thereby driving the output shaft 12 to rotate, and realizing the second stage of speed reduction from the planetary carrier 1 to the output shaft 12; therefore, in the process of rotation, the active face gear 5 drives the planetary cylindrical gear constrained by the fixed face gear 3 to revolve and rotate, thereby being able to drive the planetary carrier 1 and the non-fixed face gear 4 to rotate around their own axes;

[0150] Specifically, each time the planetary cylindrical gear 2 rolls on the tooth surface of the fixed face gear 3, it drives the non-fixed face gear 4 and the output shaft 12 to rotate by an angle; the angle is the angle corresponding to the number of consecutive teeth on the non-fixed face gear 4 that is equal to the difference in the number of teeth between the non-fixed face gear 4 and the fixed face gear 3; for example, when the difference in the number of teeth between the non-fixed face gear 4 and the fixed face gear 3 is three, the angle is the center angle corresponding to the teeth of three consecutive non-fixed face gears 4;

[0151] The transmission ratio i of the second stage reduction (i.e. the speed ratio between the planet carrier 1 and the output shaft 12) HO for:

[0152]

[0153] Among them, n O is the rotation speed of the non-fixed face gear 4 and the output shaft 12;

[0154] n H is the rotation speed of the planet carrier 1 and the input shaft 11;

[0155] n S is the speed of the fixed face gear 3; n S =0;

[0156] Z S is the number of teeth of the fixed face gear 3;

[0157] Z O is the number of teeth of the non-fixed face gear 4.

[0158] The total transmission ratio i of the secondary reduction (i.e. the speed ratio of the input shaft 11 to the output shaft 12) is IO for:

[0159]

[0160] Among them, ZS is the number of teeth of the fixed face gear 3;

[0161] Z I is the number of teeth of the driving face gear 5;

[0162] Z O is the number of teeth of the non-fixed face gear 4.

[0163] It can be seen from the above formula that the transmission ratio i of the utility model IO It has nothing to do with the number of teeth of the planetary cylindrical gear 2, so the structural design is flexible.

[0164] It can also be seen from the above formula that the smaller the number of teeth of the active face gear 5, the larger the transmission ratio. In the specific structural design, in addition to reducing the difference in the number of teeth (Z O -Z S ), the diameter of the driving face gear 5 can also be reduced, that is, the number of teeth Z of the driving face gear 5 can be reduced. I To further increase the total transmission ratio i IO .

[0165] The utility model can not only realize the advantages of simple hollow structure, compact size, stable transmission and strong bearing capacity, but also has the following advantages:

[0166] (1) A wider range of reduction ratios;

[0167] The utility model can realize two-stage deceleration and can more than double the transmission ratio without affecting the transmission efficiency. Can effectively improve the output torque density.

[0168] Since the output speed of the commonly used driving motor is high, at least hundreds of revolutions per minute or even thousands of revolutions per minute, and the joints of the robot only need to achieve a small range of low-speed rotation, a reducer with a large reduction ratio must be used. The utility model can meet this requirement.

[0169] (2) Wider input speed range;

[0170] The utility model can reduce the revolution speed of the planetary cylindrical gear 2 by more than one time under the same input speed, that is, can reduce the centrifugal force of the planetary cylindrical gear 2 by more than four times, thereby avoiding the influence of the centrifugal force of the planetary cylindrical gear 2 on the mechanism during revolution, thereby effectively improving the applicability of the reducer.

[0171] On the contrary, under the condition that the maximum revolution speed allowed by the planetary cylindrical gear 2 is certain, the utility model can increase the speed of the input shaft 11 by more than one time, thereby facilitating the selection of the input motor.

[0172] In this embodiment, the number of the planetary cylindrical gears 2 is two; of course, the number of the planetary cylindrical gears 2 can also be three or even more, as long as the planetary cylindrical gears 2 are evenly distributed along the circumference of their revolution center.

[0173] Obviously, in applications where the rotation speed of the planet carrier 1 is not high or the eccentric vibration can be ignored, only one planetary cylindrical gear 2 may be used.

[0174] Since the utility model is a hollow structure with light weight, the axes of the input shaft 11 and the output shaft 12 of the utility model can extend in any direction.

[0175] As another application of the utility model, the input shaft and the output shaft can be interchanged, and in this case, the utility model can be used as a speed increasing mechanism.

[0176] As a third application of the present invention, the planet carrier 1 can be fixedly connected to another output shaft; in this case, the transmission mechanism can provide two outputs.

[0177] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these changes and modifications.

Claims

1. A mechanical transmission mechanism, characterized in that: include: a planet carrier, capable of rotating about its axis; At least one planetary cylindrical gear connected to the planet carrier; the planetary cylindrical gear deviates from the axis of the planet carrier; as well as The coaxially arranged fixed face gear and the non-fixed face gear mesh with the planetary cylindrical gear at the same time; the fixed face gear and the non-fixed face gear are arranged on the same side; The fixed face gear and the non-fixed face gear have different numbers of teeth, thereby forming a difference in the number of teeth.

2. The mechanical transmission mechanism according to claim 1, characterized in that: The planet carrier is fixedly connected to the input shaft, and the input shaft can drive the planet carrier to rotate around its rotation axis; the non-fixed face gear is fixedly connected to the output shaft; Alternatively, the non-fixed face gear is fixedly connected to the input shaft, and the input shaft can drive the non-fixed face gear to rotate around its rotation axis; and the planet carrier is fixedly connected to the output shaft.

3. The mechanical transmission mechanism according to claim 1, characterized in that: There are more than two planetary cylindrical gears; the planetary cylindrical gears are evenly distributed along the circumference of the planet carrier.

4. The mechanical transmission mechanism according to claim 1, characterized in that: The diameters of the fixed face gear and the non-fixed face gear are larger than the diameter of the planet carrier, and the fixed face gear, the non-fixed face gear and the planetary cylindrical gear are all arranged outside the planet carrier; Alternatively, the diameters of the fixed face gear and the non-fixed face gear are smaller than the diameter of the planet carrier, and the fixed face gear, the non-fixed face gear and the planetary cylindrical gear are all arranged in the inner cavity of the planet carrier.

5. The mechanical transmission mechanism according to claim 1, characterized in that: The number of teeth of the fixed face gear is greater than the number of teeth of the non-fixed face gear; or the number of teeth of the fixed face gear is less than the number of teeth of the non-fixed face gear.

6. The mechanical transmission mechanism according to claim 1, characterized in that: The fixed face gear is arranged on the radial outer side of the non-fixed face gear; or, the fixed face gear is arranged on the radial inner side of the non-fixed face gear.

7. The mechanical transmission mechanism according to claim 1, characterized in that: The rotation axes of the fixed face gear and the non-fixed face gear are collinear with the rotation axis of the planet carrier.

8. The mechanical transmission mechanism according to claim 1, characterized in that: The number of the planetary cylindrical gears is not greater than the tooth difference between the fixed face gear and the non-fixed face gear.

9. The mechanical transmission mechanism according to claim 1, characterized in that: The axial direction of the planetary spur gear extends along the radial direction of the planet carrier.

10. The mechanical transmission mechanism according to claim 1, characterized in that: The fixed face gear and the non-fixed face gear mesh with the planetary cylindrical gear at the same shaft angle.

11. The mechanical transmission mechanism according to claim 1, characterized in that: The planet carrier is a hollow structure.

12. The mechanical transmission mechanism according to claim 1, characterized in that: Every time the planetary cylindrical gear rolls one circle on the tooth surface of the fixed face gear, it drives the non-fixed face gear and the output shaft to rotate through an angle; the size of the angle is the angle corresponding to the number of consecutive teeth on the non-fixed face gear that is equal to the difference in the number of teeth between the non-fixed face gear and the fixed face gear.

13. The mechanical transmission mechanism according to claim 1, characterized in that: The planet carrier is fixedly connected to the input shaft, and the non-fixed face gear is fixedly connected to the output shaft; The transmission ratio between the input shaft and the output shaft is HO for: Among them, n H is the rotation speed of the planet carrier, that is, the rotation speed of the input shaft; n O is the speed of the non-fixed face gear, that is, the speed of the output shaft; Z O is the number of teeth of the non-fixed face gear; Z S is the number of teeth on the fixed face gear.

14. The mechanical transmission mechanism according to claim 1, characterized in that: The non-fixed face gear is fixedly connected to the input shaft, and the planet carrier is fixedly connected to the output shaft; the transmission ratio between the input shaft and the output shaft is i IH for: Among them, n H is the speed of the planet carrier, that is, the speed of the output shaft; n I is the speed of the non-fixed face gear, that is, the speed of the input shaft; Z I is the number of teeth of the non-fixed face gear; Z S is the number of teeth on the fixed face gear.

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