Differential self-locking mechanism

Abstract

The utility model discloses a differential self-locking mechanism, and relates to the technical field of mechanical transmission, the differential self-locking mechanism comprises a rotating shaft, a driven gear is mounted on the rotating shaft, and one side of the driven gear is engaged with a driving gear; the rotating shaft is provided with an external thread section, and the external thread section is connected with a pressing device used for adjusting the friction force between the driven gears. Wherein the driven gear comprises a first gear body and a second gear body, the first gear body is in sliding fit with the rotating shaft, and the second gear body and the rotating shaft are fixed and rotate synchronously; the modulus of the first gear and the modulus of the second gear are the same, the number of teeth of the first gear is at least one tooth smaller than that of the second gear, the base circle diameter of the first gear and the base circle diameter of the second gear are the same, and the reference circle diameter of the first gear and the reference circle diameter of the second gear are different. The differential self-locking device has the advantages that efficient transmission is kept when the electric actuator works, stability and reliability are improved by the aid of the gear circumference reversing principle in a self-locking state, and differential and high-precision self-locking effects are achieved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of mechanical transmission, in particular to a differential self-locking mechanism. BACKGROUND

[0002] As one of the core components in modern industrial automation systems, electric actuators play a crucial role in various fields such as industrial production, building control, and energy management. Their main function is to achieve precise position control of mechanical devices, ensuring the stable operation and efficient work of the entire system. With the advancement of technology, the application range of electric actuators is continuously expanding, and the requirements for their performance are increasingly improving, especially in terms of safety and reliability. However, in actual operation, due to external force interference, power interruption, or system failure, electric actuators often exhibit reverse rotation or displacement out of control, which not only reduces the efficiency of the equipment, but also may cause serious safety risks.

[0003] In practical applications, it is found that there are some obvious shortcomings. The braking force provided is insufficient to meet the protection needs in the case of severe impact, the response speed is slow and cannot timely stop the occurrence of unexpected situations, in addition, there is a large reverse gap affecting the positioning accuracy and the structure is too complicated increasing the manufacturing cost and being not conducive to later maintenance. CONTENT OF THE INVENTION

[0004] In order to improve the problems of electric actuators in actual application, such as reverse rotation or displacement out of control, insufficient braking force of self-locking, slow response speed, and large reverse gap, the application provides a differential self-locking mechanism.

[0005] The differential self-locking mechanism provided by the application adopts the following technical scheme:

[0006] A differential self-locking mechanism, comprising a rotating shaft, a driven gear is installed on the rotating shaft, and a driving gear is engaged on one side of the driven gear; an external thread section is formed on the rotating shaft, and a pressing device is connected to the external thread section for adjusting the friction between the driven gears; wherein the driven gear comprises gear one and gear two, the gear one is in sliding fit with the rotating shaft, and the gear two is fixed with the rotating shaft and rotates synchronously; the modulus of the gear one and the gear two is the same, the number of teeth of the gear one is at least one less than that of the gear two, the base circle diameters of the gear one and the gear two are equal, and the pitch circle diameters of the gear one and the gear two are different.

[0007] The end of the rotating shaft is connected with the control valve, and any position of the valve in the opening and closing process can be accurately controlled by the electric actuator, thereby improving the precision in actual working conditions.

[0008] Optionally, the pressing device comprises a wave washer and a lock nut, the wave washer is sleeved on the rotating shaft, the wave washer abuts against one side of the gear one away from the gear two, and the lock nut and the wave washer abut against each other away from the side of the gear one.

[0009] By adopting the above technical scheme, the wave washer can provide elastic pressure, the pressure is transmitted to the gear one through the adjustment of the lock nut, thereby changing the contact pressure between the gear one and the gear two and effectively controlling the friction therebetween, which not only ensures smooth transmission between the two gears in normal operation, but also enhances the friction to achieve self-locking effect under specific working conditions, thereby improving the safety and reliability of the electric actuator.

[0010] Optionally, the rotating shaft is provided with a gear for engaging with the adjacent gear.

[0011] By adopting the above technical scheme, the gear and the rotating shaft are integrally formed, and the gear and the gear one engaged therewith are driven as the rotating shaft rotates.

[0012] Optionally, the gear two is provided with a groove on the side facing the gear one, the groove is provided with a flat washer, and the flat washer abuts against the gear one.

[0013] By adopting the above technical scheme, the flat washer is arranged in the groove of the gear two and abuts against the gear one, which can effectively isolate the gear one and the gear two and prevent wear caused by direct contact therebetween, thereby prolonging the service life of the parts. At the same time, the arrangement of the flat washer ensures that the friction between the gear one and the gear two is stable and controllable, which provides protection for realizing the precise differential self-locking function. Through the non-direct contact mode, the maintenance cost is reduced, and the reliability and stability of the entire differential self-locking mechanism are improved.

[0014] Optionally, the gear one is provided with a groove, and the wave washer is located in the groove, and the wave washer is coaxial with the rotating shaft.

[0015] By using the above technical scheme, the groove is arranged on the gear one to accommodate the wave washer, so that the wave washer can be accurately arranged coaxially with the rotating shaft, and the pressure applied by the wave washer is uniformly distributed on the surface of the gear one, thereby improving the stability of the friction between the gear one and the gear two.

[0016] Optionally, the rotating shaft is provided with a shaft head one and a shaft head two, the diameter of the shaft head one is smaller than that of the shaft head two, the gear one is installed on the shaft head one, and the gear two is installed on the shaft head two.

[0017] By using the above technical scheme, the shaft head with different outer diameters is matched with the gear with different inner diameters, so that the gear one and the gear two can be accurately installed and stably mounted, the assembly process is simplified, and the effective and convenient friction force is provided for the gear one and the gear two, which is helpful for accurately controlling the differential self-locking mechanism.

[0018] Optionally, the diameter of the driving gear is smaller than that of the driven gear.

[0019] By using the above technical scheme, the transmission efficiency is ensured, the wear is reduced, the service life is prolonged, the resistance to be overcome during starting is reduced, the operation is more stable and efficient, and the loss is reduced.

[0020] Optionally, the gear one and the rotating shaft are gap-fitted, and the gear two and the rotating shaft are interference-fitted.

[0021] By using the above technical scheme, when the gear two and the rotating shaft rotate, the gear one does not hinder the rotation of the rotating shaft.

[0022] In summary, the present application has at least one of the following beneficial technical effects:

[0023] 1. By using different gears of the gear one and the gear two and different assembly modes of the two gears and the rotating shaft, when the electric actuator is self-locked, the gear one and the gear two generate opposite circumferential forces, and the friction between the two gears realizes stable self-locking state, thereby effectively reducing the occurrence of reverse rotation or displacement out of control;

[0024] 2. The wave washer and the lock nut are used to adjust the friction between the gear one and the gear two, improve the adjustability of the self-locking mechanism, and the external thread segment on the rotating shaft is used to cooperate with different numbers of driven gears, thereby improving the applicability and achieving the effect of flexibly adjusting the braking force according to different working conditions;

[0025] 3. The shaft head one and the shaft head two on the rotating shaft have different outer diameters, which are matched with the gear one and the gear two, thereby improving the positioning accuracy and simplifying the assembly and maintenance. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from these drawings without any creative effort.

[0027] Figure 1 is a schematic diagram of the present application showing the engaged state of the driving gear and the driven gear.

[0028] Figure 2 is a schematic diagram of the present application showing the structure of the assembly of the driven gear and the shaft.

[0029] Figure 3 is a schematic diagram of the present application showing the structure of the assembly of the gear two on the shaft.

[0030] Figure 4 is a sectional view of the driven gear of the present application.

[0031] Figure 5 is a schematic diagram of the structure of the shaft of the present application.

[0032] Reference signs: 1, lock nut; 2, wave washer; 3, gear one; 4, flat washer; 5, gear two; 6, shaft; 7, driving gear; 8, shaft head one; 9, shaft head two; 10, driven gear; 11, external thread section; 12, compression device. DETAILED DESCRIPTION

[0033] The following will be described in combination with the drawings Figure 1 - the drawings Figure 5 The present application will be further described in detail.

[0034] The embodiment of the present application discloses a differential self-locking mechanism.

[0035] Referring to Figure 1 and Figure 2 , it comprises a shaft 6, a driven gear 10, a driving gear 7 and a compression device 12. Among them, the shaft 6 is integrally formed with a gear, which is engaged with its adjacent gear, and the shaft 6 is provided with an external thread section 11 for connecting the compression device 12 to adjust the friction between the driven gears 10, thereby realizing the self-locking function, achieving the effect of improving the safety and reliability of the electric actuator, the driven gear 10 is installed on the shaft 6, the driving gear 7 on one side of the driven gear 10 is engaged with it, and the diameter of the driving gear 7 is smaller than that of the driven gear 10, which ensures the transmission efficiency and reduces the wear, prolongs the service life, reduces the resistance to overcome when starting, is more stable and efficient, and reduces the energy loss.

[0036] Referring toFigure 1 and Figure 2 As shown, the driven gear 10 includes gear 3 and gear 5, and the driving gear 7 is gear 3. Gear 3 and the rotating shaft 6 are in sliding fit, i.e. clearance fit. Gear 5 and the rotating shaft 6 are fixed and rotate synchronously, i.e. interference fit. Gear 3 and gear 5 have the same module. Gear 1 has at least one less tooth than gear 2. The base circles of the two gears are equal, but the difference in the number of teeth results in different pitch circle diameters, which allows the circumferential force directions of the two gears to be opposite under certain conditions, thereby triggering a self-locking mechanism.

[0037] When the electric actuator is in normal operation, the drive gear 7 drives gear 3 and gear 5 to rotate in the same direction, so that the circumferential forces of gear 3 and gear 5 are in the same direction; when the electric actuator is self-locking, it drives the rotating shaft 6 to drive gear 5 to rotate, and the circumferential forces of gear 3 and gear 5 are in opposite directions.

[0038] See Figure 5 As shown, the rotating shaft 6 has two shaft heads, namely shaft head 1 8 and shaft head 2 9. The diameter of shaft head 1 8 is smaller than that of shaft head 2 9. The bottom of shaft head 1 8 is a smooth part, and the middle part is an external thread section 11. Shaft head 1 8 is adapted to the installation of gear 1 3. The outer surface of shaft head 2 9 is provided with a circumferential array of notched grooves. The diameter of shaft head 2 9 is larger and is adapted to the installation of gear 2 5, which simplifies the assembly and disassembly of gear 1 3 and gear 2 5.

[0039] See Figure 2 As shown, the clamping device 12 consists of at least one wave washer 2 (or disc spring) and one anti-loosening nut 1. The magnitude of the rotational friction can be adjusted by adjusting the installation torque of the anti-loosening nut 1 and the wave washer 2 (disc spring). The wave washer 2 is coaxially sleeved on the rotating shaft 6. The anti-loosening nut 1 and the wave washer 2 abut against each other on the side away from gear 3. The anti-loosening nut 1 and the rotating shaft 6 are coaxially aligned and connected by threads. By changing the installation torque of wave washer 2 (or disc spring) and anti-loosening nut 1 of different specifications, quantities or stacking methods, the magnitude of the friction between gear 3 and gear 5 can be adjusted. Pressure is applied to gear 3 through the wave washer 2 (or disc spring), and the pressure causes rotational friction to be formed between gear 3 and gear 5.

[0040] The compression of the wave washer 2 creates a pressure F1 on gear 3. F1 generates a frictional force between gear 3 and gear 5, i.e., f = μF1 (μ is the coefficient of friction between the flat washer 4 and the gear). Meanwhile, gear 3 has fewer teeth than gear 5, so the circumferential force Ft1 of gear 3 is less than the circumferential force Ft2 of gear 5, which facilitates the self-locking effect through the frictional force.

[0041] See Figure 3 and Figure 4As shown, the gear two 5 is provided with a groove, the flat washer 4 is placed in the groove, the end face of the flat washer 4 abuts against the gear one 3, the flat washer 4 is arranged as a friction plate between the gear one 3 and the gear two 5, direct friction of the two gears is avoided, maintenance cost is reduced, in the assembly process, the cooperation precision between the components needs to be maintained, the annular groove is provided on the gear one 3, the wave washer 2 is placed in the groove, the shaft 6 should be coaxially and accurately aligned with the wave washer 2, uniform force distribution is ensured without load deviation, and unnecessary interference phenomenon caused by misalignment is avoided.

[0042] The implementation principle of the differential self-locking mechanism in the embodiment of the application is as follows: when the shaft 6 of the electric actuator is connected with the valve for controlling the valve to move to any position; in the assembly process, the gear two 5 is first installed on the shaft head two 9 of the shaft 6 in a press-in manner through interference fit, the flat washer 4 is placed in the groove on the gear two 5, secondly, the gear one 3 is placed on the shaft head one 8 of the shaft 6 through clearance fit, and the wave washer 2 is placed in the groove of the gear one 3, different numbers of gears are placed according to actual working conditions, and finally the lock nut 1 is screwed onto the outer threaded section 11 on the shaft 6 and presses the wave washer 2, so that the driving gear 7 can drive the assembled driven gear 10 to rotate.

[0043] When the shaft 6 is connected with the corresponding valve, the gear three is driven to rotate the gear one 3 and the gear two 5 in the same direction, the circumferential force directions of the two gears are the same, because the gear one 3 is clearance fit with the shaft 6, only the gear two 5 that is interference fit with the shaft 6 drives the shaft 6 to rotate, and the gear one 3 does not hinder the rotation of the shaft 6, so that the normal operation state is achieved.

[0044] When in the self-locking state, because the shaft 6 can only drive the gear two 5 to rotate, the gear one 3 generates circumferential force opposite to that of the gear two 5, the circumferential force Ft1 of the gear one 3 plus the friction force f between them is greater than the circumferential force Ft2 of the gear two 5, that is, f+Ft1>Ft2, self-locking is formed, so that the occurrence of reverse rotation or displacement out of control is effectively reduced, the requirements of high precision, high reliability and fast response under emergency stop are met.

[0045] Unless otherwise defined, technical terms or scientific terms used in the present application shall have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Unless otherwise defined, the terms "first", "second" or "third" and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. The terms "one", "another", "an" or "some" as well as similar referents in the context of describing the specification and claims are to be construed to be open-ended, i.e., to cover both singular and plural referents unless otherwise indicated. The terms "including", "containing" or "comprising" and the like are not intended to exclude other integers or steps, but to "include" or "comprise" other integers or steps unless otherwise indicated. The terms "connected", "coupled" or "pathway" and the like are not limited to direct connections, couplings or pathways, but can also include indirect connections, couplings or pathways unless otherwise indicated.

[0046] The above are only preferred embodiments of the present application, not intended to limit the protection scope of the present application, therefore: any equivalent changes made according to the structure, shape, principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A differential self-locking mechanism, characterized in that: Includes a rotating shaft (6), on which a driven gear (10) is mounted, and a driving gear (7) meshes with one side of the driven gear (10); the rotating shaft (6) has an external thread section (11), and the external thread section (11) is connected to a clamping device (12) for adjusting the friction between the driven gears (10); The driven gear (10) includes a first gear (3) and a second gear (5). The first gear (3) is slidably engaged with the rotating shaft (6), and the second gear (5) is fixed to the rotating shaft (6) and rotates synchronously. The first gear (3) and the second gear (5) have the same module. The first gear (3) has at least one less tooth than the second gear (5). The base circle diameters of the first gear (3) and the second gear (5) are equal. The pitch circle diameters of the first gear (3) and the second gear (5) are different.

2. The differential self-locking mechanism according to claim 1, characterized in that: The clamping device (12) includes a wave washer (2) and a locking nut (1). The wave washer (2) is sleeved on the rotating shaft (6). The wave washer (2) abuts against the side of gear one (3) away from gear two (5). The locking nut (1) and the wave washer (2) abut against the side away from gear one (3). The locking nut (1) and the rotating shaft (6) are coaxially threaded together.

3. A differential self-locking mechanism according to claim 1, characterized in that: The rotating shaft (6) is provided with a gear for meshing with its adjacent gear.

4. A differential self-locking mechanism according to claim 1, characterized in that: The second gear (5) has a groove on the side facing the first gear (3), and a flat washer (4) is provided in the groove, which abuts against the first gear (3).

5. A differential self-locking mechanism according to claim 2, characterized in that: The gear (3) has a groove, the wave washer (2) is located in the groove, and the wave washer (2) and the rotating shaft (6) are coaxial.

6. A differential self-locking mechanism according to claim 1, characterized in that: The rotating shaft (6) has a shaft head one (8) and a shaft head two (9). The diameter of the shaft head one (8) is smaller than the diameter of the shaft head two (9). The gear one (3) is mounted on the shaft head one (8), and the gear two (5) is mounted on the shaft head two (9).

7. A differential self-locking mechanism according to claim 1, characterized in that: The diameter of the driving gear (7) is smaller than the diameter of the driven gear (10).

8. A differential self-locking mechanism according to claim 1, characterized in that: The first gear (3) and the shaft (6) are in clearance fit, and the second gear (5) and the shaft (6) are in interference fit.

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