Worm gear box with three-layer planetary reduction mechanism

Abstract

The utility model relates to worm wheel box technical field especially is involved in a kind of worm wheel box of three-layer planetary reduction mechanism, including box, worm wheel and the worm that is engaged with worm wheel transmission, the gear shaft is equipped in the one end of the worm, the position of the gear shaft is additionally equipped with three-layer planetary reduction mechanism and the shell that is covered on three-layer planetary reduction mechanism in box, three-layer planetary reduction mechanism includes diameter sequentially decreasing first reduction mechanism, second reduction mechanism and third reduction mechanism, the shell is ladder type that is adapted to the shape of three-layer planetary reduction mechanism, and shell inner wall is equipped with the stepped inner tooth surface for being engaged with three-layer planetary reduction mechanism, the utility model is equipped with three-stage planetary reduction mechanism by setting ladder type, improves overall transmission efficiency, and multi-stage reduction substantially improves output torque.

Description

Technical Field

[0001] This utility model relates to the field of worm gearbox technology, and in particular to a worm gearbox with a three-layer planetary reduction mechanism. Background Technology

[0002] A worm gear reducer, also known as a worm gear reducer, is a traditional transmission device consisting of a worm gear, worm, shaft, bearing, and housing. It adopts a horizontal split structure along the axis of the worm gear. The housing is usually made of cast iron, while heavy-duty models use cast steel. The housing base and cover are assembled with bolts and locating pins to ensure the accuracy of the bearing hole axis.

[0003] Patent CN209622021U discloses a lightweight worm gear box, which uses a precision-cast aluminum alloy housing and worm wheel, resulting in fewer processing steps, a lower scrap rate, and improved overall production efficiency. However, the above solution still suffers from low transmission efficiency and a relatively simple structure, relying solely on the cooperation between the worm and the worm wheel for transmission, which leads to a relatively low output torque. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings and deficiencies of the existing technology and to provide a worm gearbox with a three-layer planetary reduction mechanism. This invention improves the overall transmission efficiency by setting a stepped three-stage planetary reduction mechanism, and the multi-stage reduction significantly increases the output torque.

[0005] The technical solution adopted by this utility model is as follows: a worm gear box with a three-layer planetary reduction mechanism, including a box body, a worm wheel and a worm gear meshing with the worm wheel. One end of the worm gear is provided with a gear shaft. The box body is also provided with a three-layer planetary reduction mechanism and a shell covering the three-layer planetary reduction mechanism at the position corresponding to the gear shaft. The three-layer planetary reduction mechanism includes a first-stage reduction mechanism, a second-stage reduction mechanism and a third-stage reduction mechanism with successively decreasing diameters. The shell is stepped to adapt to the shape of the three-layer planetary reduction mechanism, and the inner wall of the shell is provided with a stepped internal tooth surface for meshing with the three-layer planetary reduction mechanism.

[0006] The stepped internal gear surface includes a first internal gear surface, a second internal gear surface, and a third internal gear surface, which are respectively meshed with a first-stage reduction mechanism, a second-stage reduction mechanism, and a third-stage reduction mechanism. The first-stage reduction mechanism includes a first internal gear ring, a first planetary gear, and a first sun gear. The first internal gear ring meshes with a gear shaft. The first planetary gear is connected to the first internal gear ring via a cylindrical pin and simultaneously meshes with the first sun gear and the first internal gear surface. The second-stage reduction mechanism includes a second internal gear ring, a second planetary gear, and a second sun gear. The second internal gear ring meshes with the first sun gear. The second planetary gear is connected to the second internal gear ring via a cylindrical pin and simultaneously meshes with the second sun gear and the second internal gear surface. The third-stage reduction mechanism includes a third internal gear ring, a third planetary gear, and a third sun gear. The third internal gear ring meshes with the second sun gear. The third planetary gear is connected to the third internal gear ring via a cylindrical pin and simultaneously meshes with the third sun gear and the third internal gear surface. The third sun gear penetrates the outer shell and is also provided with a rolling bearing between itself and the outer shell.

[0007] The first planetary gears are three in number and are evenly distributed around the first sun gear; the second planetary gears are four in number and are evenly distributed around the second sun gear; and the third planetary gears are three in number and are evenly distributed around the third sun gear.

[0008] The diameters of the first planetary gear, the second planetary gear, and the third planetary gear also decrease sequentially.

[0009] The three-layer planetary reduction mechanism is also connected to an input component for handwheel or motor drive connection. The input component includes an input gear, an end cover, and fasteners. The three-layer planetary reduction mechanism includes a third sun gear. The outer peripheral wall of the third sun gear is provided with a strip-shaped groove extending axially. The input gear is sleeved on the third sun gear, and the inner wall of the input gear is provided with a strip-shaped protrusion that matches the strip-shaped groove. The end cover is fixed to the end of the third sun gear by fasteners, and the diameter of the end cover is larger than the diameter of the third sun gear.

[0010] The outer peripheral wall of the third sun gear is provided with a circumferential groove, which is also connected to the strip groove, and the axial width of the groove is greater than the thickness of the input gear.

[0011] The end cap is provided with a locking block that is embedded in a strip groove.

[0012] The beneficial effects of this utility model are as follows: By setting up a first-stage, second-stage, and third-stage planetary reduction mechanism, this utility model forms a multi-stage reduction transmission chain, achieving a high reduction ratio, thereby significantly improving the output torque. At the same time, the synergistic effect of the planetary gear transmission and the worm gear optimizes the power transmission path, reduces energy loss, and improves the overall transmission efficiency. The outer shell adopts a stepped design adapted to the shape of the three-layer planetary reduction mechanism, and the inner wall is provided with a stepped internal tooth surface, which makes the reduction mechanism of each stage mesh tightly, reducing the overall volume and weight. The stepped internal tooth surface ensures the precise meshing and load distribution of each stage of planetary gears, reduces gear wear and vibration noise, and improves transmission smoothness and service life. At the same time, the rigid connection between the housing and the outer shell further ensures the accuracy of the bearing hole axis and reduces the failure rate. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, obtaining other drawings based on these drawings without creative effort still falls within the scope of this utility model.

[0014] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the structure of this utility model without the box body and outer shell; Figure 3 This is a cross-sectional schematic diagram of the three-layer planetary reduction mechanism in this utility model; Figure 4 This is an exploded view of the three-layer planetary reduction mechanism in this utility model; Figure 5 for Figure 4 An illustration of the explosion from another perspective; Figure 6 This is a partially enlarged schematic diagram of the input component in this utility model; In the diagram, 1-box body, 2-worm gear, 3-worm, 4-gear shaft, 5-outer shell, 6-first-stage reduction mechanism, 7-second-stage reduction mechanism, 8-third-stage reduction mechanism, 9-first internal gear surface, 10-second internal gear surface, 11-third internal gear surface, 12-first internal gear ring, 13-first planetary gear, 14-first sun gear, 15-cylindrical pin, 16-second internal gear ring, 17-second planetary gear, 18-second sun gear, 19-third internal gear ring, 20-third planetary gear, 21-third sun gear, 22-rolling bearing, 23-input gear, 24-end cover, 25-fastener, 26-strip groove, 27-strip protrusion, 28-ring groove, 29-block. Detailed Implementation

[0015] To make the objectives, technical solutions and advantages of this utility model clearer, the utility model will be described in further detail below with reference to the accompanying drawings.

[0016] It should be noted that all uses of "first" and "second" in the embodiments of this utility model are for the purpose of distinguishing two entities or parameters with the same name but different names. It is clear that "first" and "second" are only for the convenience of expression and should not be construed as limiting the embodiments of this utility model. Subsequent embodiments will not explain this in detail.

[0017] The directional and positional terms used in this utility model, such as "up," "down," "front," "back," "left," "right," "inner," "outer," "top," "bottom," and "side," are merely for reference to the accompanying drawings. Therefore, the directional and positional terms used are for the purpose of explaining and understanding this utility model, and not for limiting the scope of protection of this utility model.

[0018] like Figures 1 to 6 As shown, this is an embodiment of the present invention: a worm gear box with a three-layer planetary reduction mechanism, including a box body 1, a worm wheel 2, and a worm 3 that meshes with the worm wheel 2. One end of the worm 3 is provided with a gear shaft 4. The box body 1 is also provided with a three-layer planetary reduction mechanism and a shell 5 covering the three-layer planetary reduction mechanism at the position corresponding to the gear shaft 4. The three-layer planetary reduction mechanism includes a first-stage reduction mechanism 6, a second-stage reduction mechanism 7, and a third-stage reduction mechanism 8 with successively decreasing diameters. The shell 5 is stepped to adapt to the shape of the three-layer planetary reduction mechanism, and the inner wall of the shell 5 is provided with a stepped internal tooth surface for meshing with the three-layer planetary reduction mechanism.

[0019] The beneficial effects of this design are as follows: By setting up first-, second-, and third-stage planetary reduction mechanisms, this utility model forms a multi-stage reduction transmission chain, achieving a high reduction ratio and thus significantly increasing the output torque. At the same time, the synergistic effect of the planetary gear transmission and the worm gear optimizes the power transmission path, reduces energy loss, and improves the overall transmission efficiency. The outer shell adopts a stepped design adapted to the shape of the three-layer planetary reduction mechanism, and the inner wall has stepped internal tooth surfaces, which allows the reduction mechanisms at each stage to mesh tightly, reducing the overall volume and weight. The stepped internal tooth surfaces ensure the precise meshing and load distribution of the planetary gears at each stage, reducing gear wear and vibration noise, improving transmission smoothness and service life. Meanwhile, the rigid connection between the housing and the outer shell further ensures the accuracy of the bearing hole axis, reducing the failure rate.

[0020] Further configured, the stepped internal gear surface includes a first internal gear surface 9, a second internal gear surface 10, and a third internal gear surface 11, which respectively mesh with the first-stage reduction mechanism 6, the second-stage reduction mechanism 7, and the third-stage reduction mechanism 8. The first-stage reduction mechanism 6 includes a first internal gear ring 12, a first planetary gear 13, and a first sun gear 14. The first internal gear ring 12 meshes with the gear shaft 4. The first planetary gear 13 is connected to the first internal gear ring 12 via a cylindrical pin 15, and the first planetary gear 13 simultaneously meshes with the first sun gear 14 and the first internal gear surface 9. The second-stage reduction mechanism 7 includes a second internal gear ring 16, a second planetary gear 17, and a second sun gear 18. The second internal gear ring 16 meshes with the first sun gear 14. The second planetary gear 17 is connected to the second internal gear ring 16 through a cylindrical pin 15, and the second planetary gear 17 also meshes with the second sun gear 18 and the second internal gear surface 10. The three-stage reduction mechanism 8 includes a third internal gear ring 19, a third planetary gear 20, and a third sun gear 21. The third internal gear ring 19 meshes with the second sun gear 18. The third planetary gear 20 is connected to the third internal gear ring 19 through a cylindrical pin 15, and the third planetary gear 20 also meshes with the third sun gear 21 and the third internal gear surface 11. The third sun gear 21 penetrates the outer casing 5 and is also provided with a rolling bearing 22 between itself and the outer casing 5.

[0021] The beneficial effects of this design are as follows: It clearly defines the specific path of power transmission, driven by the gear shaft and transmitted step-by-step through the first, second, and third stage reduction mechanisms. This series structure of internal gear ring-planet gear-sun gear, where the sun gear drives the planet gears to rotate, and the planet gears, through meshing with the internal gear surfaces, revolve, thus driving the internal gear ring to rotate. The internal gear ring then drives the sun gear of the next stage, resulting in continuous and compact power transmission. It maximizes the use of radial space, achieving extremely high reduction ratios and torque density. It clearly specifies that each stage of planet gear simultaneously meshes with the central sun gear and the corresponding stepped internal gear surfaces on the outer casing, resulting in significant improvements in structural compactness, transmission smoothness, and operational reliability. This design transforms the outer casing into a robust, integral component with internal gears, ensuring precise alignment and stable meshing of each gear stage, effectively distributing the load, and improving the smoothness and reliability of the transmission. The third sun gear serves as the input shaft and is supported on the outer casing by rolling bearings. The rolling bearings reduce frictional losses, further enhancing the mechanical efficiency and long-term durability of the entire transmission system.

[0022] Further configuration: the number of the first planetary gears 13 is three and they are evenly distributed around the first sun gear 14; the number of the second planetary gears 17 is four and they are evenly distributed around the second sun gear 18; and the number of the third planetary gears 20 is three and they are evenly distributed around the third sun gear 21.

[0023] The beneficial effects of this configuration are as follows: by setting four planetary gears that bear a larger load and distributing them evenly, the meshing contact area is effectively increased. Meanwhile, the first and third stages adopt a symmetrical layout of three planetary gears, which achieves uniform load distribution, thereby significantly improving the load-bearing capacity and smoothness of the intermediate stage transmission.

[0024] Furthermore, the diameters of the first planetary gear 13, the second planetary gear 17, and the third planetary gear 20 decrease sequentially.

[0025] The beneficial effects of this design are as follows: the gradient change in the diameter of the planetary gears perfectly matches the stepped inner cavity and internal tooth surface of the outer casing, allowing each stage of the reduction mechanism to be tightly accommodated in the corresponding radial space, achieving efficient utilization of three-dimensional space. Thus, while compressing the overall volume to the extreme, it integrates three-stage high reduction ratio transmission. The gradual decrease in diameter is precisely calculated, and it matches the number of teeth of each stage of gears to achieve optimal reduction ratio distribution.

[0026] Furthermore, the three-layer planetary reduction mechanism is also connected to an input component for transmission via a handwheel or motor. The input component includes an input gear 23, an end cap 24, and a fastener 25. The three-layer planetary reduction mechanism includes a third sun gear 21. The outer peripheral wall of the third sun gear 21 is provided with an axially extending strip groove 26. The input gear 23 is sleeved on the third sun gear 21, and the inner wall of the input gear 23 is provided with a strip protrusion 27 that matches the strip groove 26. The end cap 24 is fixed to the end of the third sun gear 21 by the fastener 25, and the diameter of the end cap 24 is larger than the diameter of the third sun gear 21.

[0027] The beneficial effects of this design are as follows: the input gear, through the engagement of its inner wall's strip-shaped protrusions with the outer wall's strip-shaped grooves of the third sun gear, forms a highly efficient torque transmission connection without relative rotation. The keyway-type fitting structure can transmit large torques, avoiding the gaps, wear, and loosening problems that may occur with flat key connections, significantly improving the rigidity and reliability of the transmission connection. The end cap, fixed to the end of the third sun gear by fasteners, has a diameter larger than that of the third sun gear. This design allows the end cap to act as an effective axial baffle, firmly locking the input gear onto the third sun gear and preventing axial movement, ensuring the stability and safety of the transmission chain under high-speed or variable-load conditions. The fasteners are readily available bolts from existing technologies.

[0028] Furthermore, the outer peripheral wall of the third sun gear 21 is provided with an annular groove 28 that surrounds the circumference. The annular groove 28 is also connected to the strip groove 26, and the axial width of the annular groove 28 is greater than the thickness of the input gear 23.

[0029] The beneficial effects of this setting are as follows: when the input gear slides into the ring groove, the transmission connection with the third sun gear can be disconnected, and the input gear can rotate relative to the third sun gear, thus achieving the effect of stopping the worm gear transmission. Even if the input gear is still rotating under the drive of the handwheel or motor, the input gear will not drive the third sun gear to rotate.

[0030] As a further feature, the end cap 24 is provided with a locking block 29 for embedding a strip groove 26.

[0031] The beneficial effects of this design are as follows: the end cap can rotate coaxially with the third sun gear through the locking block, preventing the end cap from rotating relative to the third sun gear and causing the bolt to loosen from the third sun gear.

[0032] The above-disclosed embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the claims of the present utility model shall still fall within the scope of the present utility model.

Claims

1. A worm gearbox with a three-layer planetary reduction mechanism, comprising a housing (1), a worm gear (2), and a worm (3) meshing with the worm gear (2), characterized in that: One end of the worm (3) is provided with a gear shaft (4). The housing (1) is also provided with a three-layer planetary reduction mechanism and a shell (5) covering the three-layer planetary reduction mechanism at the position corresponding to the gear shaft (4). The three-layer planetary reduction mechanism includes a first-stage reduction mechanism (6), a second-stage reduction mechanism (7), and a third-stage reduction mechanism (8) with decreasing diameters in sequence. The shell (5) is stepped to adapt to the shape of the three-layer planetary reduction mechanism, and the inner wall of the shell (5) is provided with a stepped internal tooth surface for meshing with the three-layer planetary reduction mechanism.

2. The worm gearbox with a three-layer planetary reduction mechanism according to claim 1, characterized in that: The stepped internal gear surface includes a first internal gear surface (9), a second internal gear surface (10), and a third internal gear surface (11) for meshing with a first-stage reduction mechanism (6), a second-stage reduction mechanism (7), and a third-stage reduction mechanism (8), respectively. The first-stage reduction mechanism (6) includes a first internal gear ring (12), a first planetary gear (13), and a first sun gear (14). The first internal gear ring (12) meshes with a gear shaft (4). The first planetary gear (13) is connected to the first internal gear ring (12) through a cylindrical pin (15), and the first planetary gear (13) meshes with both the first sun gear (14) and the first internal gear surface (9). The second-stage reduction mechanism (7) includes a second internal gear ring (16), a second planetary gear (17), and a second sun gear (18). The second internal gear ring (16) meshes with the first sun gear (18). 16) meshes with the first sun gear (14), the second planet gear (17) is connected to the second internal gear ring (16) through a cylindrical pin (15), and the second planet gear (17) meshes with the second sun gear (18) and the second internal gear surface (10) at the same time. The three-stage reduction mechanism (8) includes a third internal gear ring (19), a third planet gear (20) and a third sun gear (21). The third internal gear ring (19) meshes with the second sun gear (18), the third planet gear (20) is connected to the third internal gear ring (19) through a cylindrical pin (15), and the third planet gear (20) meshes with the third sun gear (21) and the third internal gear surface (11) at the same time. The third sun gear (21) penetrates the outer shell (5) and a rolling bearing (22) is also provided between it and the outer shell (5).

3. A worm gearbox with a three-layer planetary reduction mechanism according to claim 2, characterized in that: The number of the first planetary gears (13) is three and they are evenly distributed around the first sun gear (14), the number of the second planetary gears (17) is four and they are evenly distributed around the second sun gear (18), and the number of the third planetary gears (20) is three and they are evenly distributed around the third sun gear (21).

4. A worm gearbox with a three-layer planetary reduction mechanism according to claim 2, characterized in that: The diameters of the first planetary gear (13), the second planetary gear (17), and the third planetary gear (20) also decrease sequentially.

5. A worm gearbox with a three-layer planetary reduction mechanism according to claim 1, characterized in that: The three-layer planetary reduction mechanism is also connected to an input component for handwheel or motor drive connection. The input component includes an input gear (23), an end cap (24), and a fastener (25). The three-layer planetary reduction mechanism includes a third sun gear (21). The outer peripheral wall of the third sun gear (21) is provided with a strip groove (26) extending axially. The input gear (23) is sleeved on the third sun gear (21), and the inner wall of the input gear (23) is provided with a strip protrusion (27) that matches the strip groove (26). The end cap (24) is fixed to the end of the third sun gear (21) by the fastener (25), and the diameter of the end cap (24) is larger than the diameter of the third sun gear (21).

6. A worm gearbox with a three-layer planetary reduction mechanism according to claim 5, characterized in that: The outer peripheral wall of the third sun gear (21) is provided with an annular groove (28) that surrounds the circumference. The annular groove (28) is also connected to the strip groove (26), and the axial width of the annular groove (28) is greater than the thickness of the input gear (23).

7. A worm gearbox with a three-layer planetary reduction mechanism according to claim 5, characterized in that: The end cap (24) is provided with a locking block (29) that embeds a strip groove (26).

Images