Pure roller pin rolling and sliding type RV speed reducer

Abstract

The invention discloses a pure roller pin rolling and sliding type RV speed reducer, which belongs to the technical field of high-precision speed reducer design and comprises a shell mounting seat, an input mounting end, an output framework and a two-stage speed reduction device. In the first-stage speed reduction, an input gear shaft drives a planetary gear to drive a crank camshaft to transmit power; according to the second-stage speed reduction device, a boss with an auxiliary roller pin limiting groove is arranged in a shell installation base, auxiliary roller pins are pressed into the limiting groove to serve as an outer tooth profile, main roller pin retaining holes with the same number are evenly distributed in the outer edge of a first roller pin driving disc and the outer edge of a second roller pin driving disc in a staggered mode, main roller pins are pressed into the holes to form an inner tooth profile, and the number of the main roller pins is i smaller than that of the auxiliary roller pins. And multi-tooth meshing is achieved. The eccentric boss of the crank cam shaft drives the roller pin driving disc to rotate through the conical bearing, and the main roller pin and the auxiliary roller pin are meshed in a relative differential sliding mode and rotate in the corresponding roller pin groove holes at the same time to finish speed reduction. According to the invention, the whole machine performance and the maintenance economy are improved, and the wear resistance and the precision of the product are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-precision reducer design, and particularly relates to a pure needle-roller rolling-sliding RV reducer. Background Art

[0002] With the rapid development of Industry 4.0, the rise of "5G + AI" smart factories, and the continuous deepening of intelligent manufacturing; industrial robots, robotic dogs, and humanoid robots have gradually been applied in all aspects of life. Industrial robots have been applied in various fields of industrial production, gradually replacing some repetitive and high-risk jobs and assisting humans. However, as a key component of industrial robots - the high-precision RV reducer, also known as the robot joint, accounts for one-quarter to one-third, or even more, of the entire robot production cost. At the same time, the quality of an industrial robot mainly depends on the high or low repeat positioning accuracy and service life of the reducer. The traditional RV reducer uses the cycloid pinwheel planetary transmission method to control and achieve speed reduction. The outer tooth profile of the cycloid wheel is a cycloid contour, which meshes with the pin teeth fixed on the pin tooth housing. Every time the crankshaft rotates one week, the cycloid wheel will reverse and rotate one tooth due to eccentric motion, thus achieving a high reduction ratio.

[0003] For the existing RV reducers, through research, it is found that the traditional cycloid pinwheel reduction device (RV) has the following problems: the cycloid tooth profile is required to have very high hardness, strength, wear resistance, and accuracy; this leads to complex processing technology, extremely high processing difficulty, and high cost. Moreover, during the load impact process of the cycloid tooth profile, the tooth profile is easily worn, which in turn causes an increase in the internal clearance of the reduction device, an increase in noise, a decrease in accuracy, and a low service life. Summary of the Invention

[0004] In view of this, the present invention provides a pure needle-roller rolling-sliding RV reducer to solve the above problems.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A pure needle-roller rolling-sliding RV reducer includes: a housing mounting seat, an input mounting end, an output skeleton, a first reduction device, and a second reduction device; the output skeleton, the first-stage reduction device, and the second-stage reduction device are all installed in the housing mounting seat;

[0007] The first-stage reduction device includes an input gear shaft, N planetary gears, and a crank camshaft. The input mounting end is used to fix the input gear shaft, and all N planetary gears are meshed with the input gear shaft; the input gear shaft meshes and rotates with the N planetary gears to transmit power to the crank camshaft to complete the first-stage reduction;

[0008] The second-stage reduction gear includes a first needle roller drive disc, a second needle roller drive disc, an input connection disc, auxiliary needle rollers, a first driving main needle roller, and a second driving main needle roller;

[0009] The input connection disc and the output skeleton are installed at both ends of the housing mounting seat; the two ends of the housing mounting seat are provided with coaxial first main bearing holes and second main bearing holes, and a housing needle roller boss is provided between the two holes. A plurality of auxiliary needle roller limiting grooves are evenly distributed on the housing needle roller boss;

[0010] The first needle roller drive disc and the second needle roller drive disc are respectively arranged inside the housing mounting seat. The first needle roller drive disc and the second needle roller drive disc have the same structural dimensions. The outer edges of the first needle roller drive disc and the second needle roller drive disc are respectively evenly distributed with the same number of first driving main needle roller retaining holes and second driving main needle roller retaining holes. The first driving main needle roller retaining holes and the second driving main needle roller retaining holes are staggered and distributed to form multi-tooth overlapping meshing; the first driving main needle roller is press-fitted into the first driving main needle roller retaining hole with interference, and the second driving main needle roller is press-fitted into the second driving main needle roller retaining hole with interference, and the number of the first driving main needle roller retaining holes and the second driving main needle roller retaining holes is both i less than the number of the auxiliary needle roller limiting grooves;

[0011] The crank camshaft is provided with a first eccentric boss, a second eccentric boss, a first tapered roller bearing rod, and a second tapered roller bearing rod. The first eccentric boss and the second eccentric boss are symmetrically distributed at 180°; the first needle roller drive disc is evenly distributed with a plurality of first inner bearing holes, and the second needle roller drive disc is evenly distributed with a plurality of second inner bearing holes. The first eccentric boss is connected to the first inner bearing hole by a bearing, and the second eccentric boss is connected to the second inner bearing hole by a bearing; the first eccentric boss and the second eccentric boss respectively drive the first needle roller drive disc and the second needle roller drive disc; one end of the second tapered roller bearing rod is provided with a regular polygon shaft end, and the planetary gear is press-fitted with the regular polygon shaft end of the crank camshaft through a regular polygon inner hole; the first tapered roller bearing rod and the second tapered roller bearing rod are coaxial;

[0012] The auxiliary needle rollers are press-fitted with the auxiliary needle roller limiting grooves, and the cylindrical surface protruding from the inner hole of the housing needle roller boss serves as an external tooth profile; the first driving main needle roller and the second driving main needle roller are press-fitted with the first driving main needle roller retaining hole and the second driving main needle roller retaining hole respectively, and the cylindrical surfaces protruding from the first needle roller drive disc and the second needle roller drive disc serve as internal tooth profiles; the first driving main needle roller, the second driving main needle roller and the auxiliary needle rollers form relative meshing and sliding of the internal tooth profile and the external tooth profile. While meshing, the first driving main needle roller, the second driving main needle roller and the auxiliary needle rollers rotate and roll in their respective corresponding needle roller groove holes under the action of force to complete the second-stage reduction.

[0013] Further, the planetary gear is in interference fit with the crank camshaft, and the value range of the number N of the planetary gears is: 2 ≤ N ≤ 6.

[0014] Further, the number of the first driving main needle roller retaining holes and the second driving main needle roller retaining holes is each i less than that of the auxiliary needle roller limiting grooves, and the value range of the number i is: 1 ≤ i < 3.

[0015] Further, the regular polygon shaft end of the crank camshaft is press-fitted in interference with the regular polygon inner hole of the planetary gear, and their phase angles coincide. A shaft snap ring groove is provided on the crank camshaft. The first-stage reduction device further includes a shaft snap ring. The shaft snap ring is arranged in the shaft snap ring groove, and the planetary gear and the crank camshaft are limited by the shaft snap ring.

[0016] Further, auxiliary needle roller lubricating grooves are machined on both end faces of the housing needle roller boss; lubricating grease grooves are provided on the end faces of the first needle roller driving disc and the second needle roller driving disc. The auxiliary needle roller lubricating grooves and the lubricating grease grooves are used to fill lubricating grease to form an end face oil film.

[0017] Further, the width β and the depth α of the auxiliary needle roller lubricating groove satisfy 1.5α ≤ β ≤ 2.5α; the relationship between the width b1 and the depth a1 of the lubricating grease groove satisfies

[0018] Further, a plurality of connecting skeletons are evenly distributed on the output skeleton. The connecting skeletons are fixedly connected with the input connecting disc through cylindrical locating pins and locking bolts; an oil seal blanking cover is installed in the oil seal blanking cover hole at the center of the output skeleton for sealing grease.

[0019] Further, the input installation end includes a flange cover plate and a flange receiving plate. The flange cover plate is fixedly connected with the flange receiving plate, and the circumferences of the connection parts between the flange cover plate and the flange receiving plate are all milled and bored with the same square size.

[0020] Further, the flange cover plate is provided with a first oil injection hole, a second oil injection hole and a sealing groove. The first oil injection hole and the second oil injection hole are convenient for discharging the waste liquid inside the speed reducer and at the same time for injecting lubricating grease inward; the sealing groove is convenient for the connection and sealing of the flange receiving plate to prevent liquid leakage; the flange receiving plate is provided with a deep groove ball bearing hole and a second oil seal hole. The deep groove ball bearing hole and the second oil seal hole are convenient for the disassembly-free assembly and extraction of the input gear shaft and for confirming the installation direction of the input gear shaft, and at the same time prevent the leakage of lubricating grease.

[0021] Furthermore, a plurality of avoidance holes are provided on both the first needle roller drive disk and the second needle roller drive disk. The first inner bearing hole and the avoidance holes are spaced apart on the first needle roller drive disk; the second inner bearing hole and the avoidance holes are spaced apart on the second needle roller drive disk.

[0022] The beneficial effects of the present invention are as follows:

[0023] In the present invention, auxiliary needle rollers are pressed into the needle roller limiting grooves of the housing mounting seat to act as external tooth profiles, and driving main needle rollers are pressed into the main needle roller retaining holes of the first needle roller drive disk and the second needle roller drive disk respectively to act as internal tooth profiles. When power is transmitted from the planetary gear to the crank camshaft, and then transmitted from the protrusions of the crank camshaft to the first needle roller drive disk and the second needle roller drive disk, the first driving main needle roller and the second driving main needle roller respectively engage with different auxiliary needle rollers and form relative sliding. At the same time of engagement, the first driving main needle roller and the second driving main needle roller respectively rotate and roll in the needle roller groove holes under the action of force with the auxiliary needle rollers. In the present invention, the needle roller drive disk and the driving main needle roller are completely replaced by needle roller standard parts with high precision, high hardness, and high wear resistance at the meshing part, and the cost is extremely low. At the same time, when stressed, due to being split and having self-rotation and rolling, it has a strong buffering effect, and the performance is more excellent and the service life is longer under the same working conditions. On the one hand, the part processing technology is simple, the processing precision and difficulty are reduced, the requirements for processing equipment and environment are reduced, and the overall cost is reduced; on the other hand, the vulnerable parts can be accurately replaced, the replacement is convenient, and the maintenance cost is low. At the same time, the integrally formed regular polygon shaft end of the crank camshaft of the present invention is in interference fit with the regular polygon inner hole integrally formed with the planetary gear, which can avoid the axial movement of the planetary gear under the load impact, resulting in loosening and movement of the crank camshaft inside the reducer, thereby ensuring the normal operation of the crank camshaft system inside the reducer and improving the operation stability and service life of the whole machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0025] Figure 1 It is a schematic diagram of the internal sectional structure and the assembly of each component of the pure needle roller rolling and sliding type RV reducer provided by the embodiment of the present invention;

[0026] Figure 2 It is a schematic diagram of the structure of the housing mounting seat in the pure needle roller rolling and sliding type RV reducer provided by the embodiment of the present invention;

[0027] Figure 3Schematic diagram of the structure of the first needle roller drive disk in the pure needle roller rolling and sliding type RV reducer provided by the embodiment of the present invention;

[0028] Figure 4 Schematic diagram of the output skeleton structure in the pure needle roller rolling and sliding type RV reducer provided by the embodiment of the present invention Figure 1 ;

[0029] Figure 5 Schematic diagram of the output skeleton structure in the pure needle roller rolling and sliding type RV reducer provided by the embodiment of the present invention Figure 2 ;

[0030] Figure 6 Schematic diagram of the structure of the crank camshaft in the pure needle roller rolling and sliding type RV reducer provided by the embodiment of the present invention;

[0031] Figure 7 Schematic diagram of the structure of the planetary gear in the pure needle roller rolling and sliding type RV reducer provided by the embodiment of the present invention;

[0032] Figure 8 Schematic diagram of the structure of the flange cover plate in the pure needle roller rolling and sliding type RV reducer provided by the embodiment of the present invention;

[0033] Figure 9 Schematic diagram of the structure of the flange receiving plate in the pure needle roller rolling and sliding type RV reducer provided by the embodiment of the present invention;

[0034] Figure 10 Schematic diagram of the internal structure of the housing mounting seat in the pure needle roller rolling and sliding type RV reducer provided by the embodiment of the present invention;

[0035] Figure 11 Schematic diagram of the pure needle roller rolling and sliding type motion principle in the pure needle roller rolling and sliding type RV reducer provided by the embodiment of the present invention;

[0036] Among them, in the figure:

[0037] 100 - Input gear shaft, 101 - Housing mounting seat, 102 - First needle roller drive disc, 103 - Second needle roller drive disc, 104 - Input connection disc, 105 - Output skeleton, 106 - First preloading gasket ring, 107 - Crank camshaft, 108 - Second preloading gasket ring, 109 - Spacer, 110 - Planet gear, 111 - Collar, 112 - Flange cover plate, 113 - Flange receiving plate, 114 - Oil seal blanking cover, 115 - Skeleton oil seal, 116 - First main bearing, 117 - Auxiliary needle roller, 118 - First driving main needle roller, 119 - Second driving main needle roller, 120 - Second main bearing, 121 - Locking bolt, 122 - Cylindrical positioning pin, 123 - First bearing gasket ring, 124 - First tapered roller bearing, 125 - First inner bearing, 126 - Second inner bearing, 127 - Second bearing gasket ring, 128 - Second tapered roller bearing, 129 - First inner hole snap ring, 130 - Shaft snap ring, 131 - First O-ring, 132 - Second O-ring, 133 - Deep groove ball bearing, 134 - Second inner hole snap ring, 135 - Second skeleton oil seal, 201 - Auxiliary needle roller limit groove, 202 - Housing needle roller boss, 203 - First main bearing hole, 204 - Second main bearing hole, 205 - Auxiliary needle roller lubrication groove, 301 - Avoidance hole, 302 - First driving main needle roller retaining hole, 303 - Lubricating grease groove, 304 - First inner bearing hole, 305 - First needle roller drive disc phase angle marking point, 401 - Tapered roller bearing blind hole, 402 - Connecting skeleton, 403 - First main bearing position, 404 - Oil seal blanking cover hole, 405 - Output docking end, 501 - First eccentric boss, 502 - Second eccentric boss, 503 - First tapered roller bearing rod, 504 - Second tapered roller bearing rod, 505 - Regular polygon shaft end, 506 - Shaft snap ring groove, 507 - Crank camshaft phase angle marking point, 601 - Regular polygon inner hole, 602 - Planet gear phase angle marking point, 701 - First oil injection hole, 702 - Second oil injection hole, 703 - Sealing groove, 704 - Deep groove ball bearing hole, 705 - Second oil seal hole, 706 - Flange receiving plate connection part. Detailed implementation manner

[0038] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0039] Refer to the attached Figures 1-11, the present invention provides a pure needle roller rolling and sliding type RV reducer, including a housing mounting seat 101, a first needle roller driving disc 102, a second needle roller driving disc 103, an input connection disc 104, an output skeleton 105, a first preloading gasket ring 106, a crank camshaft 107, a second preloading gasket ring 108, a spacer 109, a planetary gear 110, a collar 111, a flange cover plate 112, a flange receiving plate 113, a first-stage reduction device and a second-stage reduction device. Both ends of the housing mounting seat 101 respectively have an integrally formed first main bearing hole 203 and a second main bearing hole 204, and an integrally formed housing needle roller boss 202 between the two main bearing holes, so as to ensure its high coaxiality. And through a one-time clamping, a corresponding number, corresponding size and precision through holes uniformly distributed on the boss are drilled on the housing needle roller boss 202 by using a high-precision CNC machining center, and then redundant materials are cut off at one time by wire cutting, thus obtaining the auxiliary needle roller limiting groove 201 on the housing mounting seat 101, and an auxiliary needle roller lubricating groove 205 with a depth of α mm and a width of β is machined on both end faces of the housing needle roller boss 202. After the first preloading gasket ring 106 and the second preloading gasket ring 108 are installed, lubricating grease is filled between the end face of the first preloading gasket ring 106 and the end face of the auxiliary needle roller 117, and between the end face of the second preloading gasket ring 108 and the end face of the auxiliary needle roller 117. Under the action of high-speed centrifugal force during loading, the lubricating grease in the auxiliary needle roller lubricating groove 205 compensates for the preloading gasket ring and the end face of the auxiliary needle roller 117, so that a uniform oil film is covered between the preloading gasket ring and the auxiliary needle roller 117, and between the auxiliary needle roller 117 and the auxiliary needle roller lubricating groove 205, playing a role of sufficient lubrication and reducing wear.

[0040] The position of the auxiliary needle roller lubricating groove 205 is: D1 is the diameter corresponding to the bearing position, and D2 is the inner hole diameter of the housing needle roller boss 202;

[0041] The depth α of the auxiliary needle roller lubricating groove 205 is: α0 is the thickness of the preloading gasket ring;

[0042] The width β of the auxiliary needle roller lubricating groove 205 is: 1.5α ≤ β ≤ 2.5α;

[0043] The first needle roller drive disc 102 is evenly distributed with a plurality of relief holes 301 and a first inner bearing hole 304, and the number of relief holes 301 is the same as the number of the first inner bearing holes 304. The number of holes n is determined according to the actual application situation, generally between 2 ≤ n ≤ 6 holes. The shape of the relief hole is obtained by two concentric circles intersecting with two rays with a symmetric included angle of θ at a certain angle and then rounding R1 and R2. At the same time, through holes with a certain size and quantity are evenly distributed on the outer edge of the first needle roller drive disc 102, and then the redundant material is removed by wire cutting in one step to obtain the first driving main needle roller retaining hole 302. Lubricating grease grooves 303 with a depth of α1 mm and a width of β1 are machined on both end faces of the first needle roller drive disc 102, so that lubricating grease is filled between the first preloading gasket ring 106 and the first needle roller drive disc 102, between the first driving main needle roller 118 and the first driving main needle roller retaining hole 302, and between the first needle roller drive disc 102 and the spacer 109. Under the action of high-speed centrifugal force in the load, the lubricating grease in the lubricating grease groove 303 compensates for the end faces of the first preloading gasket ring 106 and the first needle roller drive disc 102, between the first driving main needle roller 118 and the first driving main needle roller retaining hole 302, and between the first needle roller drive disc 102 and the spacer 109, so that a uniform oil film is covered between each pair, playing a role of sufficient lubrication and reducing wear. Among them: the depth of the lubricating grease groove 303 is: b1 is the thickness of the drive disc; among them, the width of the lubricating grease groove 303 is: β1 ≤ β. And a phase angle marking point 305 of the first needle roller drive disc is made at the phase angle for selection and identification during the assembly process. In the example of the present invention, the second needle roller drive disc 103 has the same structural dimensions as the first needle roller drive disc 102, and the difference is that the second driving main needle roller retaining hole is distributed at a certain angle offset from the first driving main needle roller retaining hole 302.

[0044] A plurality of connecting skeletons 402 are evenly distributed at the connection end of the output skeleton 105, and at the same time, a plurality of tapered roller bearing blind holes 401 are evenly distributed, which are offset from the connecting skeletons 402 at a certain angle, and the number of connecting skeletons 402 is the same as the number of tapered roller bearing blind holes 401 and the number of relief holes 301 of the first needle roller drive disc. An oil seal blanking hole 404 is provided at the central through hole for sealing oil and also for observing during assembly. The reason for opening blind holes at the tapered roller bearings is to increase the overall tensile strength of the output skeleton 105 and at the same time reduce the oil leakage prevention of the oil seal device. When finely machining the tapered roller bearing blind holes 401, the output skeleton 105 must be locked with the input connection disc 104 through a cylindrical positioning pin 122 and a locking bolt 121, and the corresponding tapered roller bearing blind holes 401 of the input connection disc 104 and the output skeleton 105 are marked and positioned for one-time machining to ensure coaxiality and positional accuracy. At the same time, the first main bearing position 403 on the output skeleton 105 and the corresponding second main bearing position on the input connection disc 104 are machined with one-time clamping and fine machining to ensure their coaxiality.

[0045] The crank camshaft 107 has two eccentric bosses which are distributed at 180°, namely the first eccentric boss 501 and the second eccentric boss 502; and it is necessary to clamp and machine the first tapered roller bearing rod 503 and the second tapered roller bearing rod 504 at one time to ensure their coaxiality; and a regular polygon shaft end 505 is integrally formed on one side of the second tapered roller bearing rod 504 to ensure that its phase angle coincides with the phase angles of the two eccentric bosses, and a crank camshaft phase angle marking point 507 is made at the corresponding position.

[0046] The input mounting end structure is composed of a flange cover plate 112 and a flange receiving plate 113. One or more first oil injection holes 701 are designed at the outer edge of the flange cover plate 112, and a second oil injection hole 702 is designed on its end face, which is convenient for discharging the waste liquid inside the reducer and at the same time convenient for injecting lubricating grease inward. A sealing groove 703 is arranged on the end face of the flange cover plate 112, which is convenient for connecting the flange receiving plate 113 and sealing at the same time to prevent liquid leakage. The circumference of the connecting part is square milled and bored, which effectively reduces the weight of the part without affecting the functional performance. The size of the connecting part 706 of the flange receiving plate 113 is the same as that of the connecting part of the flange cover plate 112, and the same square milling and boring process is carried out, so that the two parts have the same appearance after being assembled while reducing their weight, with a sense of integrity, and it is also convenient to replace the flange receiving plate 113 according to different motor sizes, and the replacement and assembly are fast. A deep groove ball bearing hole 704 for fixing the input gear shaft 100 and a second oil seal hole 705 are designed on the flange receiving plate 113, which is convenient for the disassembly-free assembly and extraction of the input gear shaft 100, and at the same time prevents the leakage of lubricating grease.

[0047] Install the first main bearing 116 into the first main bearing hole 203 of the housing mounting seat 101. Install the first main bearing position 403 of the output skeleton 105 into the inner hole of the first main bearing 116. Install the skeleton oil seal 115 at the outer edge of the output docking end 405 of the output skeleton 105. Install the second main bearing 120 into the second main bearing hole 204. Install the first tapered roller bearing 124 into the tapered roller bearing blind hole 401 of the output skeleton 105. Install the first tapered roller bearing rod 503 of the crank camshaft 107 into the inner hole of the first tapered roller bearing 124. Separate the roller bearing from the first eccentric boss 501 with the first bearing spacer ring 123. Install the first inner bearing 125 and the second inner bearing 126 at the first eccentric boss 501 and the second eccentric boss 502 respectively. Install the outer edges of the first inner bearing 125 and the second inner bearing 126 into the first inner bearing hole 304 of the first needle roller drive plate 102 and the second inner bearing hole of the second needle roller drive plate 103 respectively. Install the second tapered roller bearing 128 onto the second tapered roller bearing rod 504 of the crank camshaft 107. Separate the second tapered roller bearing 128 from the second eccentric boss 502 with the second bearing spacer ring 127. Install the outer edge of the second tapered roller bearing 128 into the tapered roller bearing hole of the input connection plate 104 and limit it with the first inner hole snap ring 129. Then install the shaft collar 111 at the end of the second tapered roller bearing rod 504. After the main body assembly is completed, install the first O-ring 131 into the O-ring groove of the housing mounting seat 101. Then install the flange cover plate 112 into the input end of the housing mounting seat 101. Install the second O-ring into the sealing groove 703 of the flange cover plate 112. Install the deep groove ball bearing 133, the second inner hole snap ring 134 and the second skeleton oil seal 135 into the deep groove ball bearing hole 704, the snap ring groove and the second oil seal hole 705 of the flange bearing plate 113 in sequence.

[0048] The first-stage reduction device in the pure needle-roller rolling-sliding RV reducer mainly consists of an input gear shaft 100, planetary gears 110, a crank camshaft 107, and a shaft circlip 130. In the present invention, a regular polygon inner hole 601 is designed at the center of the planetary gear 110. Compared with the traditional spline hole, the processing technology is simple, it is convenient for grinding while the high precision is controllable, and the processing cost is reduced. The planetary gear phase angle marking point 602 is clearly marked, reducing the occurrence of unclear or incorrect marking of the phase point during the processing. The integrally formed regular polygon shaft end 505 of the crank camshaft 107 and the integrally formed regular polygon inner hole 601 of the planetary gear 110 are press-fitted through interference fit, and the shaft circlip 130 is used for limiting, making the planetary gear 110 and the crank camshaft 107 infinitely close to being integrated, which can avoid the axial movement of the planetary gear 110 under the load impact, resulting in loosening and movement of the crank camshaft 107 inside the reducer, thereby ensuring the normal operation of the crank camshaft system inside the reducer, improving the smooth operation and service life of the whole machine. The power is transmitted to the crank camshaft 107 through the meshing operation of the input gear shaft 100 and N (2 ≤ N ≤ 6) planetary gears 110 to complete the first-stage reduction.

[0049] The second stage reduction device of the present invention realizes deceleration by meshing movement of the inner tooth profile and the outer tooth profile, specifically as follows: Auxiliary needle rollers 117 are pressed into the auxiliary needle roller limiting grooves 201 uniformly distributed on the housing mounting seat 101, the number of auxiliary needle rollers 117 is equal to the number of auxiliary needle roller limiting grooves 201, the length is the same, and the auxiliary needle rollers 117 and the auxiliary needle roller limiting grooves 201 are interference fit, and the cylindrical surface of the auxiliary needle roller 117 protruding from the inner hole of the housing needle roller boss 202 is used as the outer tooth profile. The first driving main needle roller 118 is pressed into the first driving main needle roller retaining hole 302 of the first needle roller driving disk 102, the number of the first driving main needle roller 118 is equal to the number of the first driving main needle roller retaining hole 302, the length is the same, and the first driving main needle roller 118 and the first driving main needle roller retaining hole 302 are interference fit, and the cylindrical surface of the first driving main needle roller 118 protruding from the outer edge of the first needle roller driving disk 102 is used as the inner tooth profile. In the same way, the same number of second driving main needle rollers 119 are pressed into the second driving main needle roller retaining holes of the second needle roller driving disk 103. The number of the first driving main needle roller retaining holes 302 of the first needle roller driving disk 102 is i less than the number of the auxiliary needle roller limiting grooves 201 on the housing mounting seat 101 (1≤i<3). When the power is transmitted from the planetary gear 110 to the crank camshaft 107, and then transmitted to the first needle roller driving disk 102 and the second needle roller driving disk 103 by the first eccentric boss 501 and the second eccentric boss 502 of the crank camshaft 107 respectively, the different needle roller units of the first driving main needle roller 118, the second driving main needle roller 119 and the auxiliary needle roller 117 are meshed at the same time, forming a relative meshing sliding of the inner tooth width and the outer tooth profile, and at the same time of meshing, the first driving main needle roller 118, the second driving main needle roller 119 and the auxiliary needle roller 117 rotate and roll in their respective corresponding needle roller slots under the action of force, as shown in FIG. Figure 8 As shown, the second stage of deceleration is achieved. That is, this technical solution combines the cycloidal wheel formed in one piece in the traditional technology with a needle roller drive disk and a driving main needle roller, and completely replaces the meshing part with a needle roller standard with high precision, high hardness and high wear resistance. While the cost is extremely low, when subjected to force, due to the split type and self-rotating rolling, it has a strong buffering effect and lower operating noise. The first driving main needle roller 118 and the second driving main needle roller 119 respectively engage with the auxiliary needle roller 117 at the same time in a larger number and a higher overlap coefficient, making the operation smoother, the vibration amplitude smaller, the performance better under the same working conditions, and the service life longer. On the one hand, the parts processing technology is simple, the processing accuracy and difficulty are reduced, the processing equipment and environmental requirements are reduced, and the overall cost is reduced; on the other hand, the vulnerable parts can be accurately located, the replacement is convenient, and the maintenance cost is low.

[0050] The above are only specific embodiments of the present invention, and common knowledge such as specific structures and characteristics known in the art are not described in detail herein. It should be noted that for those skilled in the art, without departing from the structure of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicality of the patent. The protection scope required by this application should be based on the content of its claims, and the specific implementation manners described in the specification can be used to interpret the content of the claims.

[0051] In this specification, the various embodiments are described in a progressive manner, and the key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple, and reference can be made to the description in the method part for the relevant parts.

[0052] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A pure needle roller rolling and sliding type RV reducer, characterized in that, Comprising: A housing mounting base (101), an input mounting end, an output framework (105), a first reduction gear device, and a second reduction gear device; the output framework (105), the first-stage reduction gear device, and the second-stage reduction gear device are all mounted within the housing mounting base (101); The first-stage reduction gear device includes an input gear shaft (100), N planetary gears (110), and a crank camshaft (107), the input mounting end is used for fixing the input gear shaft (100), and the N planetary gears (110) are all meshed with the input gear shaft (100); the input gear shaft (100) meshes and operates with the N planetary gears (110) to transmit power to the crank camshaft (107) to complete the first-stage reduction; The second-stage reduction gear device includes a first needle driving disk (102), a second needle driving disk (103), an input connection disk (104), auxiliary needles (117), a first driving main needle (118), and a second driving main needle (119); The input connection disk (104) and the output framework (105) are mounted at both ends of the housing mounting base (101); both ends of the housing mounting base (101) are provided with coaxial first main bearing holes (203) and second main bearing holes (204), an outer housing needle boss (202) is provided between the two holes, and a plurality of auxiliary needle limiting grooves (201) are evenly distributed on the outer housing needle boss (202); The first needle driving disk (102) and the second needle driving disk (103) are respectively disposed inside the housing mounting base (101), the structural dimensions of the first needle driving disk (102) and the second needle driving disk (103) are the same, the outer edges of the first needle driving disk (102) and the second needle driving disk (103) are respectively evenly distributed with the same number of first driving main needle holding holes (302) and second driving main needle holding holes, the first driving main needle holding holes (302) and the second driving main needle holding holes are staggeredly distributed to form multi-tooth overlapping meshing; a first driving main needle (118) is press-fitted into the first driving main needle holding hole (302) with interference fit, a second driving main needle (119) is press-fitted into the second driving main needle holding hole with interference fit, and the number of the first driving main needle holding holes (302) and the second driving main needle holding holes is both i less than the number of the auxiliary needle limiting grooves (201); The crank camshaft (107) is provided with a first eccentric boss (501), a second eccentric boss (502), a first tapered roller bearing rod (503) and a second tapered roller bearing rod (504). The first eccentric boss (501) and the second eccentric boss (502) are symmetrically distributed at 180°. The first needle driving disc (102) is evenly provided with a plurality of first inner bearing holes (304), and the second needle driving disc (103) is evenly provided with a plurality of second inner bearing holes. The first eccentric boss (501) is in bearing connection with the first inner bearing hole (304), and the second eccentric boss (502) is in bearing connection with the second inner bearing hole. The first eccentric boss (501) and the second eccentric boss (502) respectively drive the first needle driving disc (102) and the second needle driving disc (103). One end of the second tapered roller bearing rod (504) is provided with a regular polygon shaft end (505), and the planetary gear (110) is in interference fit with the regular polygon shaft end (505) of the crank camshaft (107) through a regular polygon inner hole (601). The first tapered roller bearing rod (503) and the second tapered roller bearing rod (504) are coaxial. The auxiliary needle (117) is in interference fit with the auxiliary needle limiting groove (201), and the cylindrical surface protruding from the inner hole of the outer shell needle boss (202) serves as the outer tooth profile. The first driving main needle (118) and the second driving main needle (119) are respectively in interference fit with the first driving main needle holding hole (302) and the second driving main needle holding hole, and the cylindrical surfaces protruding from the first needle driving disc (102) and the second needle driving disc (103) serve as the inner tooth profiles. The first driving main needle (118), the second driving main needle (119) and the auxiliary needle (117) form relative meshing and sliding of the inner tooth profile and the outer tooth profile. During meshing, the first driving main needle (118), the second driving main needle (119) and the auxiliary needle (117) rotate and roll in their respective corresponding needle groove holes under the action of force to complete the second-stage deceleration.

2. The pure needle roller rolling and sliding type RV speed reducer according to claim 1, characterized in that, The planetary gear (110) is in interference fit with the crank camshaft (107), and the value range of the number N of the planetary gears (110) is: 2 ≤ N ≤ 6.

3. A pure needle-roller rolling and sliding type RV reducer according to claim 1, characterized in that The number of the first driving main needle holding holes (302) and the second driving main needle holding holes is both i less than the number of the auxiliary needle limiting grooves (201), and the value range of the number i is: 1 ≤ i < 3.

4. A pure needle roller rolling and sliding type RV speed reducer according to claim 1, characterized in that, The regular polygon shaft end (505) of the crank camshaft (107) is press-fitted with the regular polygon inner hole (601) of the planetary gear (110) with interference, and their phase angles coincide. An axial snap ring groove (506) is provided on the crank camshaft (107). The first-stage deceleration device further includes an axial snap ring (130). The axial snap ring (130) is arranged in the axial snap ring groove (506), and the planetary gear (110) and the crank camshaft (107) are limited by the axial snap ring (130).

5. A pure needle-roller rolling and sliding type RV reducer according to claim 1, characterized in that, Auxiliary needle lubricating grooves (205) are machined on both end faces of the outer shell needle boss (202); lubricating grease grooves (303) are provided on the end faces of the first needle driving disc (102) and the second needle driving disc (103), and the auxiliary needle lubricating grooves (205) and the lubricating grease grooves (303) are used to fill lubricating grease to form an end face oil film.

6. A pure needle roller rolling and sliding type RV reducer according to claim 5, characterized in that, The width β and depth α of the auxiliary needle roller lubrication groove (205) satisfy 1.5α ≤ β ≤ 2.5α; the relationship between the width b1 and depth a1 of the lubricating grease groove (303) satisfies 7. A pure needle roller rolling and sliding type RV reducer according to claim 1, characterized in that, A plurality of connecting skeletons (402) are evenly distributed on the output skeleton (105), and the connecting skeletons (402) are fixedly connected to the input connecting disc (104) through cylindrical positioning pins (122) and locking bolts (121); an oil seal blanking cover (114) is installed in the oil seal blanking cover hole (404) at the center of the output skeleton (105) for sealing grease.

8. A pure needle roller rolling and sliding type RV speed reducer according to claim 1, characterized in that, The input installation end includes a flange cover plate (112) and a flange receiving plate (113), the flange cover plate (112) is fixedly connected to the flange receiving plate (113), and the circumferences of the connection parts of the flange cover plate (112) and the flange receiving plate (113) are all milled and bored with the same square size.

9. A pure needle-roller rolling and sliding type RV speed reducer according to claim 8, characterized in that, The flange cover plate (112) is provided with a first oil injection hole (701), a second oil injection hole (702) and a sealing groove (703). The first oil injection hole (701) and the second oil injection hole (702) are convenient for discharging waste liquid inside the speed reducer and at the same time for injecting lubricating grease inward; the sealing groove (703) is convenient for the connection and sealing of the flange receiving plate (113) to prevent liquid leakage; the flange receiving plate (113) is provided with a deep groove ball bearing hole (704) and a second oil seal hole (705). The deep groove ball bearing hole (704) and the second oil seal hole (705) are convenient for the disassembly-free assembly and extraction of the input gear shaft (100), and for confirming the installation direction of the input gear shaft (100), and at the same time prevent lubricating grease from leaking.

10. A pure needle roller rolling and sliding type RV speed reducer according to claim 1, characterized in that, A plurality of avoidance holes (301) are provided on both the first needle driving disc (102) and the second needle driving disc (103). The first inner bearing hole (304) and the avoidance holes (301) are spaced apart on the first needle driving disc (102); the second inner bearing hole and the avoidance holes (301) are spaced apart on the second needle driving disc (103).

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