A mosaic worm gear for an angular rotary actuator

Abstract

This invention discloses an embedded worm gear for an angular rotary actuator, comprising an annular first steel base, an arc-shaped second steel base on the outer circumference of the annular first steel base, a sector-shaped copper worm gear fixed on the second steel base, and a slot on the symmetrical surface of the second steel base. The second steel base and the sector-shaped copper worm gear are cast together to form a cavity at the slot, which is filled with a vibration-absorbing material. The beneficial effects of this invention are: it achieves an embedded structure for the worm gear in the angular rotary actuator, ensuring the rigidity and impact resistance of the worm gear, while also providing lubrication to reduce friction; in the event of a malfunction and inability to rotate, the worm gear damages the soft sector-shaped copper worm gear, protecting the motor from burnout.

Description

Technical Field

[0001] This invention belongs to the field of vibration reduction and shock resistance technology in the field of angular rotary electric actuators, and particularly relates to an embedded worm gear for angular rotary actuators. Background Technology

[0002] Electric actuators are used to drive valves to the fully open or fully closed position. The actuators used to control valves can precisely move the valve to any position. For some high-pressure, large-diameter valves, the required output torque of the actuator is very large, and the worm gear inside the actuator is also subjected to large impact forces. The worm gear is often damaged due to excessive impact forces.

[0003] Currently, the worm gears of electric actuators are made of steel due to cost considerations. When subjected to excessive impact force, the rotation of the steel worm gear is hindered, while the motor continues to rotate, causing the steel worm gear to be forcibly engaged, resulting in heat and adhesion until it is damaged. This causes the worm gear to be damaged simultaneously and is difficult to disassemble, while also damaging the motor.

[0004] It is evident that the worm gear mechanism of existing electric actuators suffers from technical problems such as poor impact resistance, damage, and short lifespan, which in turn leads to the need for frequent maintenance and replacement of electric actuators. Summary of the Invention

[0005] The objective of this invention is to solve the technical problems of existing electric actuators with worm gears and worm shafts, which are not impact-resistant, are prone to damage, and have a short lifespan, thus requiring frequent maintenance and replacement of the electric actuators.

[0006] To achieve the above objectives, the present invention provides an embedded worm gear for an angular rotary actuator.

[0007] The specific technical solution adopted in this invention is as follows:

[0008] An embedded worm gear for an angular rotary actuator includes an annular first steel base, an arc-shaped second steel base on the outer circumference of the annular first steel base, a fan-shaped copper worm gear fixed on the second steel base, a slot on the symmetrical surface of the second steel base, and a cavity formed at the slot after the second steel base and the fan-shaped copper worm gear are cast together, the cavity being filled with a vibration-absorbing material.

[0009] Through this design, an arc-shaped second steel base is provided on the outer circumference of the annular first steel base. The second steel base is cast together with the fan-shaped copper worm wheel, forming a composite structure of copper and steel inlay. Because the worm wheel has a large number of teeth, each tooth takes a short time to rotate once, resulting in less wear. However, the worm has a small number of heads, with each head representing one tooth, taking a long time to rotate once, resulting in greater wear. To ensure that the lifespan of the worm and worm wheel is comparable and to increase the wear resistance of the worm, steel is used and hardened. The worm wheel is made of a soft material, reducing its hardness and wear resistance, which can meet the working requirements and protect the worm. Therefore, the copper and steel inlay composite structure of the worm wheel ensures the rigidity of the worm wheel base and ensures that the lifespan of the fan-shaped copper worm wheel and the worm are matched. At the same time, when subjected to a large impact force, because the fan-shaped copper worm wheel is softer, the worm will destroy the fan-shaped copper worm wheel while the worm remains intact, thus protecting the worm and also protecting the motor of the electric actuator, reducing the damage to the electric actuator under overload, and mitigating losses.

[0010] Furthermore, after the second steel substrate and the sector-shaped copper worm gear are cast together, a cavity is formed at the slot, and the cavity is filled with vibration-absorbing material. With this design, when an impact force is applied to the worm gear, the impact force is absorbed by the vibration-absorbing material, reducing the impact of the impact force on the worm gear and protecting the worm gear, as well as the motor of the electric actuator.

[0011] Preferably, the vibration-absorbing material is shear-thickening liquid STF, which is composed of polyethylene glycol and silicon microparticles. Polyethylene glycol is a widely used non-toxic liquid that can withstand a wide temperature range. The extremely fine silicon microparticles are another component of STF. When the movement is slow, the hard particles can move around freely, and the shear-thickening liquid STF remains liquid. However, when the movement is rapid, the hard particles collide with each other, hindering their movement, and the shear-thickening liquid STF becomes tough. This highly fluid liquid combined with hard microparticles can form a rigid material.

[0012] When an impact force is applied to the worm gear, the worm gear vibrates, and the vibration is transmitted to the shear thickening liquid STF, which forms a shear force on the shear thickening liquid STF. The stronger the vibration, the greater the shear force. The higher the frequency, the more viscous the shear thickening liquid STF becomes, and the more vibration energy it absorbs. When the vibration is eliminated, the shear thickening liquid STF returns to a liquid state, preparing for the absorption of the next vibration.

[0013] This reduces the impact of the impact force on the worm gear to a certain extent, protecting the worm gear and also protecting the motor of the electric actuator.

[0014] As a further improvement of the present invention, the outer arc surface of the slot is provided with an arc-shaped cover plate to prevent molten copper from entering the slot during casting.

[0015] Since the steel substrate and the fan-shaped copper worm gear are cast together, there is a possibility that the slot may be filled with liquid copper. In order to prevent the liquid copper from entering the slot, an arc-shaped cover plate is provided on the outer arc surface of the slot. This keeps the copper outside the arc-shaped cover plate and ensures that a cavity is formed in the slot.

[0016] As a further improvement of the present invention, the second steel substrate is provided with a plurality of symmetrically arranged fixing notches, the notches including an anti-rotation notch provided on the outer arc surface of the second steel substrate and an anti-detachment notch provided on the base of the inner arc surface of the second steel substrate and located at both ends of the second steel substrate.

[0017] As a further improvement of the present invention, the anti-rotation notch is U-shaped, and the anti-detachment notch is provided with an anti-rotation part and an anti-detachment part connected together. Both the anti-rotation part and the anti-detachment part are rectangular. The anti-detachment part is located at the end of the second steel base and is located below the inner side of the anti-rotation part.

[0018] The second steel substrate is arc-shaped and is set on the outer circumference of the annular first steel substrate. The anti-rotation notch is U-shaped and symmetrically set on the top of the two end faces of the second steel substrate that are perpendicular to the axis of the annular first steel substrate. The anti-detachment notch is set at the end of the second steel substrate.

[0019] As a further improvement of the present invention, six anti-rotation notches and four anti-detachment notches are provided. The number of anti-rotation notches and anti-detachment notches can be determined according to specific circumstances, aiming to ensure that the sector-shaped copper worm gear is subjected to force balance during operation and to prevent the sector-shaped copper worm gear from falling off the second steel base.

[0020] As a further improvement of the present invention, the fan-shaped copper worm gear is provided with a flange that cooperates with the anti-rotation notch and the anti-detachment notch.

[0021] As a further improvement of the present invention, the end of the second steel substrate and the end of the fan-shaped copper worm gear are provided with sealing end caps to seal the slot and form a cavity.

[0022] The sealing end cap seals both ends of the slot, forming a cavity between the slot and the sealing end cap. The cavity is filled with shear-thickening liquid STF. When an impact force is applied to the worm gear, the worm gear vibrates, and the vibration is transmitted to the shear-thickening liquid STF, creating a shear force on the STF. The stronger the vibration, the greater the shear force. The higher the frequency, the more viscous the shear-thickening liquid STF becomes, and the more vibration energy it absorbs. When the vibration is eliminated, the shear-thickening liquid STF returns to a liquid state, preparing for the next vibration absorption.

[0023] As a further improvement of the present invention, the sealing end cap is bolted to the second steel base and the sector-shaped copper worm gear. This provides a specific method for fixing the sealing end cap. Other fixing methods, such as welding or gluing, can also be used, provided that the slot can form a sealing cavity.

[0024] As a further improvement of the present invention, the sector-shaped copper worm gear is cast onto the second steel substrate by centrifugal casting of cast tin bronze.

[0025] Centrifugal casting is a technique and method in which liquid metal is injected into a high-speed rotating mold, causing the molten metal to undergo centrifugal motion to fill the mold and form a casting. Due to the centrifugal motion, the liquid metal can fill the mold well in the radial direction and form the free surface of the casting. Under the action of centrifugal force, the texture of the casting is more uniform and dense. Using this method to cast a sector-shaped copper worm gear can better fill the anti-rotation gap and anti-detachment gap with molten copper and fill the casting cavity of the sector-shaped copper worm gear.

[0026] As a further improvement of the present invention, the fan-shaped copper worm gear is formed during centrifugal casting to form worm gear teeth.

[0027] Because centrifugal casting is used, only the corresponding worm gear tooth profile needs to be set on the circumferential surface of the casting cavity of the fan-shaped copper worm gear. The liquid metal can be well filled with the corresponding worm gear tooth profile in the radial direction by centrifugal motion to form the worm gear tooth of the fan-shaped copper worm gear.

[0028] The positive effects of this invention are: it realizes the embedded structure of the worm gear in the angular rotary actuator, which ensures the rigidity and impact resistance of the worm gear, while also providing lubrication to reduce friction; when a malfunction occurs and the worm cannot rotate, the soft fan-shaped copper worm gear is damaged to protect the motor from burning out and the worm from being worn out. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of a three-dimensional embedded worm gear structure for an angular rotary actuator according to the present invention;

[0030] Figure 2 yes Figure 1 The diagram shows a structural schematic of the first and second steel bases of an embedded worm gear for an angular rotary actuator according to the present invention.

[0031] Figure 3 yes Figure 2 The image shown is an enlarged view of the embedded worm gear N of an angular rotary actuator according to the present invention.

[0032] Figure 4 yes Figure 1 The diagram shows a structural schematic of an embedded worm gear sector-shaped copper worm gear for an angular rotary actuator according to the present invention.

[0033] Figure 5 yes Figure 2 The image shows a front view of the first and second steel bases of an embedded worm gear for an angular rotary actuator according to the present invention;

[0034] Figure 6 yes Figure 5 The figure shown is a bottom view of an embedded worm gear for an angular rotary actuator according to the present invention;

[0035] Figure 7 yes Figure 6 The figure shown is a cross-sectional view along line AA of an embedded worm gear for an angular rotary actuator according to the present invention;

[0036] Legend: 1—First steel base, 2—Fixing hole, 3—Keyway, 4—Second steel base, 5—Fan-shaped copper worm gear, 6—Anti-rotation notch, 7—Anti-detachment notch, 701—Anti-rotation part, 702—Anti-detachment part, 703—Connecting part, 8—Anti-detachment flange, 801—Anti-rotation flange, 9—Slot, 10—Sealing gasket, 11—Sealing end cap, 12—Fixing bolt. Detailed Implementation

[0037] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments: Specific implementation examples:

[0039] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. 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. Therefore, they should not be construed as limitations on this invention.

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0041] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0042] Example 1:

[0043] An embedded worm gear for an angular rotary actuator includes an annular first steel base, an arc-shaped second steel base on the outer circumference of the annular first steel base, a fan-shaped copper worm gear fixed on the second steel base, a slot on the symmetrical surface of the second steel base, and a cavity formed at the slot after the second steel base and the fan-shaped copper worm gear are cast together, the cavity being filled with a vibration-absorbing material.

[0044] Specifically, such as Figure 1 , Figure 2 , Figure 4 and Figure 5 As shown, the embedded worm gear includes a first steel base 1, which is annular. A fixing hole 2 is located at the center of the first steel base for fixing the embedded worm gear onto the worm gear shaft. After casting, a keyway 3 is machined into the wall of the fixing hole 2 in the first steel base 1 during subsequent processing to prevent the embedded worm gear from rotating on the worm gear shaft. A second steel base 4 is provided on the outer circumference of the first steel base 1. The second steel base 4 has four pairs of symmetrically arranged fixing notches. These notches include three pairs of anti-rotation notches 6 located on the outer arc surface of the second steel base and two pairs of anti-detachment notches 7 located at the base of the inner arc surface of the second steel base and at both ends of the second steel base. The anti-rotation notches 6 and the anti-detachment notches 7 are U-shaped. A slot 9 is provided on the symmetrical surface of the second steel base 4, such as... Figure 7 As shown, when the second steel substrate 4 and the fan-shaped copper worm gear 5 are cast together, a cavity is formed at the slot 9, and the cavity is filled with vibration-absorbing material.

[0045] Through this design, an arc-shaped second steel base 4 is provided on the outer circumference of the annular first steel base 1. The second steel base 4 is cast together with the fan-shaped copper worm wheel 5 to form a composite structure of copper and steel inlay. Because the worm wheel has a large number of teeth, each tooth takes a short time to rotate once, resulting in less wear. However, the worm has a small number of heads, with each head representing one tooth, taking a long time to rotate once, resulting in greater wear. To ensure that the lifespan of the worm and worm wheel is comparable and to increase the wear resistance of the worm, steel is used and quenched. The worm wheel is made of a soft material, reducing its hardness and wear resistance, which can meet the working requirements and protect the worm. Therefore, the copper and steel inlay composite structure of the worm wheel ensures the rigidity of the worm wheel base and ensures that the lifespan of the fan-shaped copper worm wheel 5 matches that of the worm. At the same time, when subjected to a large impact force, because the fan-shaped copper worm wheel 5 is relatively soft, the worm will destroy the fan-shaped copper worm wheel 5 while the worm remains intact, thus protecting the worm and also protecting the motor of the electric actuator, reducing the damage to the electric actuator under overload, and mitigating losses.

[0046] Furthermore, after the second steel substrate 4 and the fan-shaped copper worm gear 5 are cast together, a cavity is formed at the slot 9. The cavity is filled with vibration-absorbing material. When an impact force is applied to the worm gear, the impact force is absorbed by the vibration-absorbing material, which reduces the impact force on the worm gear and protects the worm gear, as well as the motor of the electric actuator.

[0047] Preferably, the vibration-absorbing material is a shear-thickening liquid STF. When an impact force is applied to the worm gear, the worm gear vibrates, and the vibration is transmitted to the shear-thickening liquid STF, which forms a shear force on the shear-thickening liquid STF. The stronger the vibration, the greater the shear force and the higher the frequency. The more viscous the shear-thickening liquid STF becomes, the more vibration energy it absorbs. When the vibration is eliminated, the shear-thickening liquid STF returns to a liquid state, preparing for the absorption of the next vibration.

[0048] This reduces the impact of the impact force on the worm gear to a certain extent, protecting the worm gear and also protecting the motor of the electric actuator.

[0049] Example 2:

[0050] Based on Example 1, such as Figure 3 The anti-detachment notch 7 shown has an anti-rotation part 701 and an anti-detachment part 702 connected together. Both the anti-rotation part 701 and the anti-detachment part 702 are rectangular. The anti-detachment part 702 is located at the end of the second steel base 4 and below the inner side of the anti-rotation part 701. The second steel base 4 is arc-shaped and is set on the outer circumferential surface of the annular first steel base 1. The anti-rotation notch 6 is U-shaped and symmetrically set on the top of the two end faces of the second steel base 4 that are perpendicular to the axis of the annular first steel base 1. The anti-detachment notch 7 is set at the end of the second steel base 4.

[0051] Example 3:

[0052] Based on Embodiment 2, as a further improvement of the present invention, the outer arc surface of the slot 9 is provided with an arc-shaped cover plate to prevent molten copper from entering the slot during casting.

[0053] Since the steel substrate is cast together with the fan-shaped copper worm gear, there is a possibility that the slot may be filled with liquid copper. In order to prevent the liquid copper from entering the slot, an arc-shaped cover plate is provided on the outer arc surface of the slot. This keeps the copper outside the arc-shaped cover plate and ensures that a cavity is formed in the slot.

[0054] Example 4:

[0055] like Figure 7 As shown, based on Embodiment 3, the end of the second steel substrate 4 and the end of the fan-shaped copper worm gear 5 are provided with sealing end caps 11 to seal the slot and form a cavity.

[0056] The sealing end cap 11 seals both ends of the slot 9, so that the slot 9, the fan-shaped copper worm gear 5 and the sealing end cap form a cavity. The cavity is filled with shear thickening liquid STF. When the impact force acts on the worm gear, the worm gear vibrates. The vibration is transmitted to the shear thickening liquid STF, which forms a shear force on the shear thickening liquid STF. The stronger the vibration, the greater the shear force. The higher the frequency, the more viscous the shear thickening liquid STF becomes, and the more vibration energy it absorbs. When the vibration is eliminated, the shear thickening liquid STF returns to a liquid state, preparing for the next vibration absorption.

[0057] The sealing end cap 11 is connected to the second steel base and the sector copper worm gear by fixing bolts 12 and is sealed with a sealing gasket 12.

[0058] Example 5:

[0059] Based on Embodiment 3, the sector-shaped copper worm gear 5 is cast onto the second steel substrate 4 by centrifugal casting of cast tin bronze.

[0060] Centrifugal casting is a technique and method that involves injecting molten metal into a high-speed rotating mold, causing the molten metal to fill the mold and form a casting through centrifugal motion. Because of the centrifugal motion, the molten metal can effectively fill the mold radially, forming the free surface of the casting. Furthermore, under the action of centrifugal force, the casting has a more uniform and dense texture. Using this method to cast a sector-shaped copper worm gear allows for better filling of the anti-rotation and anti-detachment gaps with molten copper, and completely filling the casting cavity of the sector-shaped copper worm gear. During centrifugal casting, the worm gear teeth are formed. Due to the use of centrifugal casting, only the corresponding worm gear tooth shape needs to be set on the circumferential surface of the casting cavity of the sector-shaped copper worm gear. The centrifugal motion then allows the molten metal to effectively fill the corresponding worm gear tooth shape radially, forming the worm gear teeth of the sector-shaped copper worm gear.

[0061] The foregoing has broadly outlined some aspects and features of the various embodiments and should be interpreted as merely illustrative of potential applications. Other beneficial results can be obtained by applying the disclosed information in different ways or by combining aspects of the disclosed embodiments. Further aspects and a more complete understanding can be obtained based on the detailed description of exemplary embodiments with reference to the accompanying drawings, within the scope defined by the claims.

[0062] The above embodiments provide a detailed description of the present invention. Of course, the above description is not intended to limit the present invention, nor is the present invention limited to the examples described above. Any changes, modifications, additions, reductions, or substitutions made by those skilled in the art within the scope of the present invention are also within the protection scope of the present invention.

Claims

1. An embedded worm gear for an angular rotary actuator, comprising an annular first steel base, an arc-shaped second steel base disposed on the outer circumference of the annular first steel base, and a fan-shaped copper worm gear fixed on the second steel base, characterized in that, The second steel substrate has a slot on its symmetrical surface, and an arc-shaped cover plate on the outer arc surface of the slot to prevent molten copper from entering the slot during casting. After the second steel substrate and the fan-shaped copper worm gear are cast together, a cavity is formed at the slot. The ends of the second steel substrate and the ends of the fan-shaped copper worm gear are provided with sealing end caps to seal the slot and form a cavity. The sealing end caps block both ends of the slot, so that the slot and the sealing end caps form a cavity. The cavity is filled with vibration-absorbing material, which is shear-thickening liquid STF. The fan-shaped copper worm gear is cast onto the second steel substrate by centrifugal casting of cast tin bronze.

2. The embedded worm gear for an angular rotary actuator according to claim 1, characterized in that, The second steel substrate is provided with several symmetrically arranged fixing notches, including anti-rotation notches on the outer arc surface of the second steel substrate and anti-detachment notches on the base of the inner arc surface of the second steel substrate and located at both ends of the second steel substrate.

3. The embedded worm gear for an angular rotary actuator according to claim 2, characterized in that, The anti-rotation notch is U-shaped, and the anti-detachment notch has an anti-rotation part and an anti-detachment part connected together. Both the anti-rotation part and the anti-detachment part are rectangular. The anti-detachment part is located at the end of the second steel base and is located on the inner side below the anti-rotation part.

4. The embedded worm gear for an angular rotary actuator according to claim 3, characterized in that, There are 6 anti-rotation notches and 4 anti-detachment notches.

5. An embedded worm gear for an angular rotary actuator according to any one of claims 2 to 4, characterized in that, The fan-shaped copper worm gear is provided with a flange that matches the anti-rotation notch and the anti-detachment notch.

6. An embedded worm gear for an angular rotary actuator according to claim 5, characterized in that, The sealing end cap is bolted to the second steel base and the sector-shaped copper worm gear.

7. An embedded worm gear for an angular rotary actuator according to claim 6, characterized in that, The fan-shaped copper worm gear is formed during centrifugal casting.

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