Conjugated gear reducer

Abstract

The embodiment of the invention provides a conjugate type gear speed reducer, and relates to the technical field of speed reducers. According to the conjugate gear reducer, two eccentric bodies are formed by eccentric shaft sleeves, a conjugate gear is made to rotate, decelerate and swing, a plurality of driven crankshafts annularly arranged along the circumference are pushed, a plurality of shaft pins of rotating bodies inserted into the two sides of a machine shell through needle bearings are eccentrically rotated, the shaft pins are pushed to synchronously rotate, and the rotating bodies on the two sides of the machine shell rotate along with the shaft pins. If rotation of the rotating bodies on the two sides is restrained, the conjugate gear can directly push the shell to rotate, and angular velocity displacement in rotation can be accurately removed. The conjugate type gear reducer can achieve high-precision positioning transmission, shorten the axial distance, reduce the manufacturing cost and further enable products to be popularized.

Description

Technical Field

[0001] This invention relates to the field of speed reducer technology, and more specifically, to a conjugate gear reducer. Background Technology

[0002] As is well known, an existing type of cycloidal deceleration device, such as Figure 1 and Figure 2 As shown, this is a single-stage reduction gear. Through two eccentric bodies outside the eccentric bushing 28, the internal gear 04 meshes with the first external gear 42 and the second external gear 43, generating a self-rotating, decelerating oscillation. This causes multiple shaft pins 01 connected to the output shaft 38 to rotate eccentrically by twice the oscillation distance (2e), outputting a reduced angular velocity displacement. It is a typical shaft-output type cycloidal reducer, characterized by its compact structure, high reduction ratio, and low cost, and is widely used in general mechanical transmission applications. Due to the large eccentric oscillation distance (2e), such as... Figure 2 As shown, without precise support points on the outside, the angular velocity displacement output is unstable, the positioning is not accurate, and it is not suitable for precision transmission equipment.

[0003] Another existing cycloidal speed reducer, such as Figure 3 and Figure 4 As shown, this is a two-stage reduction gear. The first stage of reduction is achieved by the central gear 23 of the motor bushing 44 driving multiple driven gears 24 of the eccentric shaft 26 to rotate, radially pushing the first external gear 42 and the second external gear 43 to rotate, thus performing the second stage of reduction. The torque after reduction radially pushes the eccentric shaft 26 to rotate, causing the first rotating body 16 and the second rotating body 17 on both sides of the housing 11 to rotate. It has a compact structure and a high reduction ratio. Multiple eccentric shafts 26 arranged circumferentially rotate and are used for outputting the relative angular velocity after reduction. Because the eccentric shaft 26 and the needle roller 46 can rotate without backlash, high-precision positioning can be achieved, making it popular in the robotic arm market. However, the external gear disk cannot accommodate the large swing distance (e) at low speeds and the diameter of the internal gear 03. Furthermore, to avoid flexural bending of the gear disk, a low reduction ratio design is abandoned. Due to its high cost, complex manufacturing, and high noise at the first stage of reduction of the involute gear, it is more suitable for specific markets and less suitable for automated process equipment and precision equipment such as conveyor belts. Summary of the Invention

[0004] The purpose of this invention is to provide a conjugate gear reducer that can achieve high-precision positioning and transmission, shorten axial distance, reduce manufacturing costs, and further popularize the product.

[0005] The embodiments of the present invention can be implemented as follows:

[0006] The present invention provides a conjugate gear reducer, which includes an eccentric bushing, a conjugate gear, a housing, a first rotating body, and a second rotating body.

[0007] The eccentric bushing is formed as a whole into two eccentric bodies, with the center of the eccentric bushing penetrating through it. The two ends of the eccentric bushing are supported by ball bearings in the central holes of the first and second rotating bodies.

[0008] The conjugate gear has a conjugate bearing hole at its center. The conjugate gear is mounted on an eccentric bushing through two intermediate ball bearings. Multiple conjugate crankshaft holes and bolt holes are staggered along the circumference of the conjugate gear. A driven crankshaft is installed in the conjugate crankshaft hole. A needle roller bearing is installed in the driven crankshaft. A pin is installed in the needle roller bearing. The pin is inserted into the first rotating body and the second rotating body. A bolt is installed in the bolt hole. The bolt axially connects the first rotating body and the second rotating body. The bolt and the bolt hole do not contact each other during rotation.

[0009] The housing contains an internal gear that meshes with a conjugate gear. The internal gear consists of multiple cylindrical pins arranged in a ring at equal intervals.

[0010] In an optional embodiment, the conjugate gear is composed of two halves of the external gear symmetrically arranged at a position twice the axial swing distance, wherein the tooth roots at the central symmetry point are connected in a tangential manner.

[0011] In an optional implementation, a conjugate bearing hole refers to a through hole formed by symmetrically arranging the outer diameter circles of the ball bearings outside the eccentric bushing at a position twice the axial swing distance.

[0012] In an optional implementation, a conjugate crankshaft bore refers to a through hole formed by symmetrically arranging the outer diameter circles of the passive crankshaft at a position twice the axial swing distance.

[0013] In an optional implementation, a passive crankshaft refers to a crankshaft composed of two eccentric bodies arranged symmetrically at 180 degrees and in phase.

[0014] In an alternative implementation, the center of the passive crankshaft is through which ball bearings and pins are placed.

[0015] In an alternative implementation, conjugate crankshaft bores on each external gear are arranged radially around the center of the external gear.

[0016] In an optional implementation, the swing distance and transmission phase of the passive crankshaft are the same as those of the eccentric bushing.

[0017] In an alternative implementation, the passive crankshaft and the matching conjugate crankshaft bore operate with a clearance fit.

[0018] In an optional embodiment, the first rotating body and the second rotating body are supported at both ends of the housing by angular contact ball bearings.

[0019] The beneficial effects of the conjugate gear reducer provided in the embodiments of the present invention include:

[0020] The conjugate gear reducer consists of two eccentric bodies formed by an eccentric bushing. The conjugate gears rotate and decelerate, driving multiple driven crankshafts arranged in a circular pattern. These crankshafts, via needle roller bearings, eccentrically rotate multiple pins on both sides of the housing, causing the pins to rotate synchronously. This allows the rotating bodies on both sides of the housing to rotate in tandem. If the rotation of the rotating bodies on both sides is inhibited, the conjugate gears can directly drive the housing to rotate, precisely eliminating angular velocity displacement during rotation. This conjugate gear reducer achieves high-precision positioning and transmission, shortens axial distance, reduces manufacturing costs, and further facilitates the widespread adoption of the product. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of an existing cycloidal deceleration device;

[0023] Figure 2 for Figure 1 A sectional view along the middle section of SS;

[0024] Figure 3 This is another existing cycloidal deceleration device;

[0025] Figure 4 for Figure 3 A cross-sectional view along the Y-axis;

[0026] Figure 5 This is a schematic diagram of the structure of the conjugate gear reducer provided in an embodiment of the present invention;

[0027] Figure 6 for Figure 5 A sectional view along the center line (CC).

[0028] Figure 7 This is a schematic diagram of a conjugate gear.

[0029] Icons: 01-Shaft pin; 02-Keyway; 04-Internal gear; 07-Cylindrical pin; 09-Shaft pin hole; 11-Housing; 13-Bolt; 14-Conjugate crankshaft hole; 15-Passive crankshaft; 16-First rotating body; 17-Second rotating body; 19-Angular contact ball bearing; 20-Ball bearing; 21-Conjugate gear; 22-Conjugate bearing hole; 23-Center gear; 24-Passive gear; 25-Needle roller bearing; 26-Eccentric shaft; 28-Eccentric bushing; 33-Bolt hole; 38-Output shaft; 41-Irregular shaped shaft pin; 42-First external gear; 43-Second external gear; 44-Motor bushing; 46-Needle roller. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0032] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0033] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0034] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0035] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0036] Please refer to Figures 5 to 7This embodiment provides a conjugate gear reducer, which includes an eccentric bushing 28, a conjugate gear 21, a housing 11, a first rotating body 16, and a second rotating body 17.

[0037] The eccentric bushing 28 is formed as a double eccentric body with a through center and a keyway 02. The two ends of the eccentric bushing 28 are supported in the center holes of the first rotating body 16 and the second rotating body 17 by ball bearings 20.

[0038] A conjugate gear 21 has a conjugate bearing hole 22 at its center, and is mounted on an eccentric bushing 28 via two intermediate ball bearings 20. Multiple conjugate crankshaft holes 14 and bolt holes 33 are staggered along the circumference of the conjugate gear 21. A driven crankshaft 15 is housed in the conjugate crankshaft hole 14, a needle roller bearing 25 is housed within the driven crankshaft 15, and a pin 01 is housed within the needle roller bearing 25. The pin 01 is inserted into the first rotating body 16 and the second rotating body 17. Bolts 13 are installed in the bolt holes 33, axially connecting the first rotating body 16 and the second rotating body 17. The bolts 13 and bolt holes 33 do not contact each other during rotation. The first rotating body 16 and the second rotating body 17 are connected by multiple bolts 13 with O-rings to form a single rotating body.

[0039] The housing 11 has an internal gear 04 that meshes with the conjugate gear 21. The internal gear 04 includes a plurality of cylindrical pins 07 arranged in a ring at equal intervals.

[0040] The first rotating body 16 and the second rotating body 17 are supported at both ends of the housing 11 by angular contact ball bearings 19.

[0041] Please see Figure 6 and Figure 7 The conjugate gear 21 is composed of two half external gears symmetrically arranged at a position twice the axial swing distance (2e), wherein the tooth roots at the central symmetry point are connected in the form of a tangent.

[0042] The conjugate bearing hole 22 refers to the through hole formed by symmetrically arranging the outer diameter circles of the ball bearings 20 outside the eccentric bushing 28 at a position twice the axial swing distance (2e).

[0043] The passive crankshaft 15 is composed of two eccentric bodies arranged symmetrically at 180 degrees and in phase. The center of the passive crankshaft 15 is through which the needle roller bearing 25 and the pin 01 inside the needle roller bearing 25 can be placed.

[0044] The conjugate crankshaft hole 14 refers to the through hole formed by symmetrically arranging the outer diameter circle of the passive crankshaft 15 at a position twice the axial swing distance (2e).

[0045] The conjugate crankshaft bores 14 on each external gear are arranged radially around the center of the external gear, rather than radially around the center of the conjugate gear 21. This provides ample space at the long shaft end, allowing for the setting of a large swing distance (e) and eccentric bore diameter in a low reduction ratio, which is not yet possible in known cycloidal transmission devices.

[0046] Please see Figure 4 To avoid deformation of the gear disc, the second type of cycloidal transmission device in the prior art is usually equipped with an irregularly shaped shaft pin 41, which has a larger shaft pin hole 09, making manufacturing more complicated and increasing costs.

[0047] In this embodiment, the swing distance (e) and transmission phase of the passive crankshaft 15 are the same as those of the eccentric bushing 28, making the transmission smooth and seamless. The swing distance (e) refers to the engagement distance (e) of the conjugate gear 21 with the internal gear 04. The double swing distance (2e) includes both the engagement and disengagement distances, where the engagement and disengagement distances are equal.

[0048] Please see Figure 7 In this embodiment, the conjugate gears 21 are symmetrically arranged with twice the swing distance (2e). Therefore, the distance between the long shaft end and the short shaft end is twice the swing distance (2e). In this way, the first external gear 42 and the second external gear 43 are symmetrically arranged, making the operation more stable.

[0049] Please see Figure 2 If the symmetrical meshing of the external gear is removed and only the embedded part is retained, and the external gear is integrated, it becomes the conjugate gear 21 provided in this embodiment. Its function and the meshing swing pattern of the embedded and embedded meshing are exactly the same as those of the separate first external gear 42 and the second external gear 43, but a more accurate concentricity can be obtained, making the meshing and meshing swing distance (e) more accurate, and the back clearance can be maintained at a precise level. If it is processed by slow wire cutting operation, the accuracy can be maintained within one arc minute.

[0050] Please see Figure 6 The conjugate bearing bore 22 is used to support the ball bearing 20 outside the eccentric bushing 28. Since the conjugate gear 21 is a disc-shaped transmission design, it cannot support two eccentrically symmetrical ball bearings 20. In order to balance the dynamic rotation, the two ball bearings 20 are actually regarded as one ball bearing 20, with only half of each bearing in contact with the conjugate bearing bore 22. The other half of the bearing is suspended and does not contact or bear force, but this does not affect the transmission performance. On the contrary, it allows the conjugate through-hole to be machined synchronously, which can obtain precise concentricity and make the transmission smoother. The two half bearings form a bearing, which allows the torque to remain unchanged. It can react immediately in both forward and reverse rotation, and the force is symmetrically distributed, which helps to form a conjugate type of wave transmission and also extends the service life of the ball bearing 20.

[0051] The passive crankshaft 15 and the matching conjugate crankshaft bore 14 operate with a micro-clearance fit and have the same variation distance (e) and transmission phase as the eccentric bushing 28, so that the passive crankshaft 15 can passively rotate with the conjugate gear 21 without backlash. Since it is a conjugate symmetrical rotation, they restrain each other, so that the relative angular velocity displacement can be precisely removed from the backlash-free rotation.

[0052] The central through hole of the passive crankshaft 15 can accommodate the needle roller bearing 25 and the pin 01. The pin 01 does not rotate and is only used to connect the first rotating body 16 and the second rotating body 17, which helps to ensure smooth and stable rotation and also avoids the generation of pulses.

[0053] Please see Figure 5 and Figure 6 The shaft pin 01 is inserted into the first rotating body 16 and the second rotating body 17, but does not rotate during transmission. The passive crankshaft 15 is supported on the needle roller bearing 25, passively follows the rotation of the conjugate gear 21, and pushes the shaft pin 01 to rotate from the diametrical direction, thus driving the first rotating body 16 and the second rotating body 17, which are connected by bolts 13, to rotate synchronously. If the rotation of the first rotating body 16 and the second rotating body 17 is inhibited, the conjugate gear 21 directly drives the internal gear 04 of the housing 11 to rotate.

[0054] A motor (not shown in the figure) can be fitted into an eccentric bushing 28 to drive the eccentric bushing 28 to rotate. This causes the conjugate gear 21 to rotate, generating a conjugate-type self-rotating reverse deceleration oscillation, which in turn drives the circumferentially arranged passive crankshaft 15 to rotate. Because the passive crankshaft 15 is framed by the conjugate crankshaft hole 14, it can rotate without backlash.

[0055] The beneficial effects of the conjugate gear reducer provided in this embodiment include:

[0056] 1. Replacing the existing first external gear 42 and second external gear 43 with a conjugate gear 21 simplifies the mechanism, shortens the axial length, and reduces costs;

[0057] 2. A conjugate gear 21 with a long shaft and a short shaft structure is used to achieve self-rotation reduction oscillation, wherein the long shaft meshes and the short shaft ends separate during transmission;

[0058] 3. The conjugate bearing hole 22 frames the eccentric bushing 28, so that the ball bearing 20 outside the eccentric bushing 28 can bear the high-speed rotation of the conjugate gear 21 in both forward and reverse directions. This can keep the ball bearing 20 in a stable and shock-free transmission and extend its service life.

[0059] 4. Multiple conjugate crankshaft holes 14 fit together with a micro-gap to frame the passive crankshaft 15, so that the passive crankshaft 15 can seamlessly follow the rotation of the decelerated conjugate gear 21, which can achieve the effect of high-precision positioning and transmission.

[0060] 5. The conjugate crankshaft bores 14 are arranged radially around the center of their respective external gears. Due to the large space at the long shaft end, the crankshaft bore arrangement with low reduction ratio and high swing distance e can be satisfied. Furthermore, due to its large resistance to bending torque, it can undertake low reduction ratio transmissions that cannot be configured in existing transmission devices.

[0061] 6. Because the concentricity machining of the conjugate gear 21 and its related components is completed in one go with high precision, the conjugate gear 21 does not need to be dynamically balanced and can rotate naturally in balance.

[0062] 7. To meet the market demand for high-precision repeatability positioning, it mainly uses conjugate components to perform conjugate-style wave deceleration transmission, similar to two cows sharing a yoke. This makes the transmission operation smoother, reduces vibration and noise, and also has a conjugate multiplicative effect on the rated torque. It is a new type of high-precision positioning deceleration transmission device.

[0063] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A conjugate gear reducer, characterized in that, The conjugate gear reducer includes an eccentric bushing (28), a conjugate gear (21), a housing (11), a first rotating body (16), and a second rotating body (17); The eccentric bushing (28) is integrally formed into two eccentric bodies. The center of the eccentric bushing (28) is through, and the two ends of the eccentric bushing (28) are supported in the central holes of the first rotating body (16) and the second rotating body (17) by ball bearings (20). The conjugate gear (21) has a conjugate bearing hole (22) at its center. The conjugate gear (21) is sleeved on the eccentric bushing (28) through two intermediate ball bearings (20). The conjugate gear (21) has multiple conjugate crankshaft holes (14) and bolt holes (33) staggered along its circumference. A driven crankshaft (15) is provided in the conjugate crankshaft hole (14). A needle roller bearing (25) is provided in the driven crankshaft (15). A shaft pin (01) is provided in the needle roller bearing (25). The shaft pin (01) is inserted into the first rotating body (16) and the second rotating body (17). A bolt (13) is provided in the bolt hole (33). The bolt (13) is axially connected to the first rotating body (16) and the second rotating body (17). The bolt (13) and the bolt hole (33) do not contact each other during rotation. The housing (11) is provided with an internal gear (04) that meshes with the conjugate gear (21). The internal gear (04) includes a plurality of cylindrical pins (07) arranged in an equidistant ring.

2. The conjugate gear reducer according to claim 1, characterized in that, The conjugate gear (21) is composed of two halves of the external gear symmetrically arranged at a position twice the axial swing distance, wherein the tooth roots at the central symmetry point are connected in the form of a tangent.

3. The conjugate gear reducer according to claim 1, characterized in that, The conjugate bearing hole (22) refers to the through hole formed by symmetrically arranging the outer diameter circle of the ball bearing (20) outside the eccentric bushing (28) at a position twice the axial swing distance.

4. The conjugate gear reducer according to claim 1, characterized in that, The conjugate crankshaft hole (14) refers to the through hole formed by symmetrically arranging the outer diameter circle of the passive crankshaft (15) at a position twice the axial swing distance.

5. The conjugate gear reducer according to claim 1, characterized in that, The passive crankshaft (15) is composed of two eccentric bodies arranged symmetrically at 180 degrees and in phase.

6. The conjugate gear reducer according to claim 1 or 5, characterized in that, The passive crankshaft (15) has a central through-hole, which can accommodate the needle roller bearing (25) and the shaft pin (01).

7. The conjugate gear reducer according to claim 2, characterized in that, The conjugate crankshaft bore (14) on each external gear is arranged radially around the center of the external gear.

8. The conjugate gear reducer according to claim 1, characterized in that, The swing distance and transmission phase of the passive crankshaft (15) are the same as those of the eccentric bushing (28).

9. The conjugate gear reducer according to claim 1, characterized in that, The passive crankshaft (15) and the matching conjugate crankshaft bore (14) operate with a clearance fit.

10. The conjugate gear reducer according to claim 1, characterized in that, The first rotating body (16) and the second rotating body (17) are supported at both ends of the housing (11) by angular contact ball bearings (19).

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