Coaxial speed reducer

Abstract

The invention relates to the technical field of speed reducers, in particular to a coaxial speed reducer which comprises a machine shell and an output shaft, the output shaft is rotationally connected to the surface of the machine shell, a resistance assembly is arranged in the machine shell and used for increasing rotation resistance of the output shaft, and a driving assembly is arranged in the machine shell and used for driving the output shaft to rotate. The driving assembly is used for driving the resistance assembly to increase the rotation resistance of the output shaft, the resistance assembly comprises a supporting plate and a rubber pad, the top end of the supporting plate is rotationally connected to the interior of the machine shell, and the rubber pad is arranged on the surface of the supporting plate. And the output shaft still keeps a rotating trend due to load inertia, and the inertia moment of the output shaft is reversely transmitted to the stopped input shaft through a gear pair, so that the problem that the instantaneous reverse impact load borne by the gear tooth surface is relatively large is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of speed reducers, and particularly to a coaxial speed reducer. Background Art

[0002] A coaxial speed reducer is a transmission device. Its core feature is that the input shaft and the output shaft are on the same central axis. It has a compact structure and occupies little space. It is suitable for scenarios where the power transmission direction needs to be coaxial and the installation position is limited. Such speed reducers achieve the conversion of rotational speed and torque through internal transmission components. According to different transmission forms, they can be divided into various types such as gear type and worm and worm gear type. Among them, the gear coaxial speed reducer is one of the most typical applications. It uses a gear pair as the core transmission component. Through the meshing of the driving gear and the driven gear, the rotational motion of the input shaft is smoothly transmitted to the output shaft. It has the advantages of high transmission efficiency, strong reliability, and simple maintenance. It is widely used in industrial machinery, automation equipment and other fields. Its coaxial design not only simplifies the layout of the mechanical system, but also ensures the stability of power transmission through the accuracy of gear meshing, becoming a common choice for scenarios requiring high-precision and high-load transmission.

[0003] When the input shaft of the existing gear coaxial speed reducer stops rotating, the output shaft still has a tendency to rotate due to the inertia of the load. Its inertia torque will be reversely transmitted to the stopped input shaft through the gear pair, resulting in the gear tooth surface being subjected to an instantaneous reverse impact load. This load causes the contact stress on the tooth surface to increase suddenly, far exceeding the stress level during steady-state operation. At the same time, it triggers torsional vibration of the gear system, intensifying the dynamic load fluctuation at the tooth surface meshing. Repeated inertia impacts will form periodic contact stress and shear stress on the surface layer and subsurface layer of the tooth surface. After exceeding the material fatigue limit, it is easy to cause the initiation and expansion of microcracks on the tooth surface, and finally lead to fatigue failures such as pitting and scuffing. Especially in the working condition of frequent stops, this effect will significantly shorten the service life of the gears. Summary of the Invention

[0004] The purpose of the present invention is to provide a coaxial speed reducer to solve the problem that when the input shaft of the existing gear coaxial speed reducer stops rotating, the output shaft still has a tendency to rotate due to the inertia of the load, and its inertia torque will be reversely transmitted to the stopped input shaft through the gear pair, resulting in a relatively large instantaneous reverse impact load on the gear tooth surface.

[0005] To achieve the above purpose, the present invention provides the following technical solutions: A coaxial speed reducer includes a housing and an output shaft. The output shaft is rotatably connected to the surface of the housing. A resistance component is arranged inside the housing. The resistance component is used to increase the rotational resistance of the output shaft. A driving component is arranged in the housing. The driving component is used to drive the resistance component to increase the rotational resistance of the output shaft.

[0006] Preferably, the resistance component includes a support plate and a rubber pad. The top end of the support plate is rotatably connected to the inside of the casing, and the rubber pad is arranged on the surface of the support plate.

[0007] Preferably, a connecting rod is rotatably connected to the bottom end of the support plate, and the bottom end of the connecting rod is rotatably connected to a vertically arranged main control rod.

[0008] Preferably, a component for controlling the up and down movement of the main control rod is arranged inside the casing.

[0009] Preferably, the component includes a lever and an auxiliary joint. The lever is rotatably connected to the casing, and the auxiliary joint is telescopically connected to one end of the lever, and the other end of the auxiliary joint is rotatably connected to the bottom end of the main control rod.

[0010] Preferably, the driving component drives the resistance component by driving the lever to rotate, and a torsion spring is fixedly connected between the lever and the casing.

[0011] Preferably, a fulcrum shaft is fixedly connected to the surface of the lever, and the fulcrum shaft is rotatably connected to the casing.

[0012] Preferably, the driving component includes a push rod and a button. The push rod is slidably connected to the inside of the casing, and the button is movably connected to the surface of the casing in a resetable manner. The button is used to drive the push rod to push the active end of the lever.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By tightly attaching the resistance component to the output shaft, the rotational resistance is increased, which can inhibit the rotation of the output shaft due to inertia, avoid the violent collision caused by the inertial impact of the internal gears, and effectively extend the service life of the gears and the whole machine; 2. Through the installation position of the fulcrum shaft of the lever, the lever principle can be used to amplify the moving distance of the driven end, so that a small displacement of the active end can cause a large stroke of the driven end, shorten the working stroke of the linear actuator, reduce its movement time, and thus accelerate the response speed of the entire mechanism; 3. By supporting two triggering methods, automatic triggering by the rotational speed sensor and manual triggering by pressing the button, it not only meets the requirements of automatic control but also facilitates manual intervention, such as debugging and emergency braking, improving the flexibility and scenario adaptability of equipment use. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic structural diagram of the whole of the present invention; Figure 2 is a schematic structural diagram of the vertical section of the casing of the present invention; Figure 3 is the enlarged view of part A in the present invention Figure 2 of the present invention; Figure 4 Structural schematic diagram of the support plate of the present invention; Figure 5 For the present invention Figure 4 Enlarged view at position B in; Figure 6 Structural schematic diagram of the vertical section of the lever of the present invention; Figure 7 Structural schematic diagram of the ejector rod of the present invention; Figure 8 Structural schematic diagram of the push rod of the present invention.

[0015] In the figure: 1, housing; 2, output shaft; 3, support plate; 4, rubber pad; 5, connecting rod; 6, main control rod; 7, auxiliary joint; 8, telescopic slider; 9, telescopic chute; 10, lever; 11, fulcrum shaft; 12, torsion spring; 13, ejector rod; 14, lower inclined surface; 15, upper inclined surface; 16, push rod; 17, limit ring; 18, return spring; 19, button; 20, limit chute. Specific embodiments

[0016] 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.

[0017] Please refer to Figures 1 to 8 , the present invention provides a technical solution.

[0018] A coaxial speed reducer includes a housing 1 and an output shaft 2. The output shaft 2 is rotatably connected to the surface of the housing 1. A resistance component is provided inside the housing 1, and the resistance component is used to increase the rotation resistance of the output shaft 2. A driving component is provided inside the housing 1, and the driving component is used to drive the resistance component to increase the rotation resistance of the output shaft 2. The resistance component includes a support plate 3 and a rubber pad 4. The top end of the support plate 3 is rotatably connected to the inside of the housing 1, so that the support plate 3 rotates around the connection point at the top end. The rubber pad 4 is provided on the surface of the support plate 3, and the rubber pad 4 can closely adhere to the surface of the output shaft 2. By rotating the support plate 3, the rubber pad 4 can be made to tightly adhere to the surface of the output shaft 2, thereby increasing the resistance when the output shaft 2 rotates. The bottom end of the support plate 3 is rotatably connected to a connecting rod 5, and the bottom end of the connecting rod 5 is rotatably connected to a vertically arranged main control rod 6. When the main control rod 6 is moved up and down, the connecting rod 5 will rotate relative to the support plate 3, and this relative rotation will drive the support plate 3 to rotate around the connection point at the top end, thereby controlling the overall distance of the support plate 3 from or close to the surface of the output shaft 2. The driving component is arranged inside the housing 1, and its function is to provide power for the resistance component and drive the resistance component to perform the action of increasing the rotation resistance of the output shaft 2.

[0019] Inside the casing 1, there is a component for controlling the up and down movement of the main control rod 6. The component includes a lever 10 and an auxiliary joint 7. The lever 10 is rotatably connected to the casing 1. The auxiliary joint 7 is telescopically connected to one end of the lever 10, and the other end of the auxiliary joint 7 is rotatably connected to the bottom end of the main control rod 6, ensuring that it can adapt to different angle changes during movement. When the end of the lever 10 with the auxiliary joint 7 tilts upward, it drives the auxiliary joint 7 to move upward. At this time, the auxiliary joint 7, through the rotational connection with the bottom end of the main control rod 6, pulls the main control rod 6 to move upward synchronously. During this process, due to the movement trajectory of the main control rod 6, the distance between it and the lever 10 changes dynamically, and the auxiliary joint 7 will perform telescopic movement at the end of the lever 10 to compensate for the distance difference caused by the angle change when the main control rod 6 moves. The principle is the same vice versa.

[0020] The synergistic effect of this telescopic compensation design ensures that the main control rod 6 can move precisely along the predetermined trajectory. As needed, a guiding groove for the main control rod 6 to slide can be opened in the casing 1 to guide the main control rod 6 to move in the vertical direction.

[0021] One end of the auxiliary joint 7 is fixedly connected with a telescopic slider 8. One end of the lever 10 is provided with a telescopic chute 9 for the telescopic slider 8 to slide. The depth and width of the chute are precisely matched according to the movement trajectory of the slider to ensure precise guiding during the sliding process. By the telescopic slider 8 sliding in the telescopic chute 9, the telescopic movement of the auxiliary joint 7 at the end of the lever 10 is realized.

[0022] The driving component realizes the purpose of driving the resistance component by driving the lever 10 to rotate. The driving component includes a rotational speed sensor and an actuator. The two work together to ensure the stable operation and timely response of the system. By the rotational speed sensor detecting the shaft stop, an electrical signal is output to trigger the actuator to act. The actuator can select a linear motion actuator, such as a cylinder or an electric push rod. By pushing one end of the lever 10 to rotate around the fulcrum, it is ensured that the driving force of the actuator needs to be greater than the resistance when the lever 10 rotates, and the response time needs to meet the real-time requirement of the shaft stop and the action at the same time, usually ≤50 ms. A torsion spring 12 is fixedly connected between the lever 10 and the casing 1. When the actuator pushes the lever 10, the torsion spring 12 stores elastic potential energy. When the controller sends a reset signal and the actuator retracts, the elastic potential energy stored in the torsion spring 12 is converted into the rotational kinetic energy of the lever 10, making it rotate and reset, so that the support plate 3 moves away from the output shaft 2.

[0023] By arranging the rubber pad 4 on the inner surface of the support plate 3 and the output shaft 2 on the inner side of the rubber pad 4, when the main control rod 6 moves downward, the support plate 3 with the rubber pad 4 will be pulled to be close to the surface of the output shaft 2. In this way, the main control rod 6 is driven to move downward synchronously through the auxiliary joint 7. The downward movement of the main control rod 6 makes the support plate 3 with the rubber pad 4 close to the surface of the output shaft 2. When the output shaft 2 rotates inertially due to the power source being cut off, the friction resistance between the rubber pad 4 and the shaft surface will synchronously generate a braking torque opposite to the rotation direction. In this way, the rotation resistance of the output shaft 2 is increased, and the continuous rotation of the output shaft 2 due to inertia is suppressed, thereby avoiding the gears in the housing 1 from colliding violently due to the inertial rotation of the output shaft 2.

[0024] The surface of the lever 10 is fixedly connected with a fulcrum shaft 11, and the fulcrum shaft 11 is rotatably connected to the housing 1. By setting the fulcrum shaft 11, the lever 10 can rotate around the fulcrum shaft 11 as the axis. By scientifically designing the installation position of the fulcrum shaft 11 on the lever 10, that is, the distance between the fulcrum shaft 11 and the two ends of the lever 10, the movement amplitude of the two ends of the lever 10 can be adjusted by using the lever principle. For example, the end of the surface of the lever 10 away from the auxiliary joint 7 is the active end, which is connected to the output end of the linear actuator and assumes the power input function. The end of the surface of the lever 10 connected to the auxiliary joint 7 is the driven end, which is responsible for transmitting the movement of the active end to the auxiliary joint 7. When the installation position of the fulcrum shaft 11 is biased toward the active end and away from the driven end, the length of the active end force arm is smaller than the length of the driven end force arm, forming a transmission structure with amplified stroke. Then, the active end of the push lever 10 undergoes a slight displacement, and the auxiliary joint 7 located at the driven end can produce a larger moving distance through the amplification effect, thereby shortening the working stroke of the linear actuator and accelerating the response speed.

[0025] The driving assembly also includes a push rod 13 and a button 19. The push rod 13 is slidably connected to the inside of the casing 1, and the button 19 is resettably connected to the surface of the casing 1. The button 19 is used to drive the push rod 13 to push the active end of the lever 10. When the button 19 is touched, the push rod 13 is triggered to push the lever 10 upward, thereby driving the main control rod 6 to move downward, so that the support plate 3 and the output shaft 2 are in close contact. When the input shaft stops rotating, the output shaft 2 stops synchronously due to the mechanical connection. At this time, the transmission gear in the casing 1 will produce an instantaneous impact collision due to the inertia moment of the output shaft 2. By touching the button 19 or operating the actuator, the support plate 3 and the output shaft 2 form a damping contact, effectively suppressing the impact load of the gear inertia collision.

[0026] The bottom end of the push rod 13 is provided with a lower inclined surface 14, and one end of the button 19 is fixedly connected to the push rod 16. The top of the push rod 16 is provided with an upper inclined surface 15 that cooperates with the lower inclined surface 14. By touching the button 19, the push rod 16 is pushed to move horizontally, and the inclined surfaces of the lower inclined surface 14 and the upper inclined surface 15 cooperate to push the push rod 13 upward, so that the push rod 13 pushes the lever 10. After the touching is completed, the button 19 is reset to drive the push rod 16 to retreat, and the push rod 13 moves downward under the action of gravity or the same reset mechanism. At the same time, the lever 10 is reset under the elastic force of the torsion spring 12, and finally the support plate 3 is automatically separated from the output shaft 2, and the reset process is automatically completed.

[0027] The surface of the button 19 is fixedly connected to the limit ring 17, and the interior of the housing 1 is provided with a limit slide groove 20 for the limit ring 17 to slide. The limit ring 17 is set to slide in the limit slide groove 20 to limit the movable range of the button 19 and prevent the push rod 16 from being separated from the contact with the push rod 13. A reset spring 18 is fixedly connected between the limit ring 17 and the housing 1. When the button 19 is touched, the reset spring 18 is compressed. When the button 19 is released, the button 19 automatically resets under the elastic force of the reset spring 18.

[0028] The specific solution is as follows: the rubber pad 4 maintains an initial spacing of 2-3mm with the surface of the output shaft 2, and no contact resistance is generated. When the input shaft stops rotating due to the power source being cut off, the speed sensor installed inside the housing 1 detects that the input shaft stops rotating, and outputs an electrical signal to the actuator. The actuator pushes the active end of the lever 10 to move upward, and the lever 10 rotates around the fulcrum shaft 11. The auxiliary joint 7 connected to the driven end of the lever 10 rises upward with the driven end, and the auxiliary joint 7 synchronously pulls the main control rod 6 to move upward, and the telescopic slider 8 at its end slides in the telescopic slide groove 9 to compensate for the spacing difference between the auxiliary joint 7 and the main control rod 6 due to the angle change.

[0029] When the main control rod 6 moves upward, the bottom end of the support plate 3 is driven to deflect toward the central axis of the output shaft 2 through the connecting rod 5, and the support plate 3 rotates with the top end as the fulcrum, so that the inner rubber pad 4 gradually fits closely to the surface of the output shaft 2, and the contact pressure increases linearly with the displacement of the main control rod 6. Due to the damping effect of the rubber pad 4, the rotation resistance of the output shaft 2 increases sharply, which effectively reduces the violent collision of the gears in the housing 1 caused by the inertial rotation of the output shaft 2.

[0030] When the actuator retracts, the active end of the lever 10 loses thrust, the compressed torsion spring 12 releases elastic potential energy, driving the lever 10 to reset, the driven end drives the auxiliary joint 7 to move downward, the main control rod 6 and the support plate 3 reset synchronously, the rubber pad 4 separates from the surface of the output shaft 2, and the system returns to the initial undamped state.

[0031] When the device encounters unexpected working conditions such as sudden vibration and instantaneous overload, resulting in abnormal inertial rotation of the output shaft 2, the operator manually touches the button 19. The button 19 moves horizontally, driving the push rod 16 fixed to its end to move synchronously. The upper inclined surface 15 of the push rod 16 contacts the lower inclined surface 14 at the bottom of the ejector rod 13. The horizontal thrust is converted into the upward thrust of the ejector rod 13 through the cooperation of the inclined surfaces. The ejector rod 13 pushes the active end of the lever 10 upward. The remaining action process is the same as the rotation of the lever 10 in the automatic control scenario. The main control rod 6 moves downward to make the rubber pad 4 tightly adhere to the surface of the output shaft 2, forming damping. After releasing the button 19, the return spring 18 pushes the button 19 back to the initial position. The ejector rod 13 descends under the action of gravity, and the lever 10 quickly resets under the action of the torsion spring 12.

[0032] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A coaxial reducer, comprising a housing (1) and an output shaft (2), characterized in that: The output shaft (2) is rotatably connected to the surface of the casing (1); a resistance component is provided inside the casing (1); the resistance component is used to increase the rotational resistance of the output shaft (2); a driving component is provided inside the casing (1); the driving component is used to drive the resistance component to increase the rotational resistance of the output shaft (2).

2. A coaxial reducer according to claim 1, characterized in that: The resistance assembly comprises a support plate (3) and a rubber pad (4); the top end of the support plate (3) is rotatably connected to the inside of the housing (1); and the rubber pad (4) is arranged on the surface of the support plate (3).

3. A coaxial reducer according to claim 2, characterized in that: The bottom end of the support plate (3) is rotatably connected to a connecting rod (5), and the bottom end of the connecting rod (5) is rotatably connected to a vertically arranged main control rod (6).

4. A coaxial reducer according to claim 3, characterized in that: A component for controlling the main control rod (6) to move up and down is arranged inside the housing (1).

5. A coaxial reducer according to claim 4, characterized in that: The assembly comprises a lever (10) and an auxiliary joint (7); the lever (10) is rotatably connected to the housing (1); the auxiliary joint (7) is telescopically connected to one end of the lever (10), and the other end of the auxiliary joint (7) is rotatably connected to the bottom end of the main control rod (6).

6. A coaxial reducer according to claim 5, characterized in that: The driving component drives the resistance component by driving the lever (10) to rotate, and a torsion spring (12) is fixedly connected between the lever (10) and the housing (1).

7. A coaxial reducer according to claim 5, characterized in that: A fulcrum shaft (11) is fixedly connected to the surface of the lever (10), and the fulcrum shaft (11) is rotatably connected to the housing (1).

8. A coaxial reducer according to claim 5, characterized in that: The driving assembly comprises a push rod (13) and a button (19); the push rod (13) is slidably connected to the inside of the housing (1); the button (19) is repositionably connected to the surface of the housing (1); and the button (19) is used to drive the push rod (13) to push the active end of the lever (10).

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