Trapezoidal screw self-locking high-efficiency electric push rod

Abstract

This invention proposes a trapezoidal lead screw self-locking high-efficiency electric actuator, comprising a housing, a motor, a pre-stage reduction mechanism, an intermediate transmission mechanism, a post-stage reduction mechanism, a bidirectional backstop, a trapezoidal lead screw, bearings, a nut, a push rod, a base hinge point, and a load hinge point. All components of this trapezoidal lead screw self-locking high-efficiency electric actuator employ structures with high transmission efficiency, achieving a total transmission efficiency exceeding 55%, significantly improving the overall thrust-to-volume ratio. Motor current can be greatly reduced, and most parts require only medium to low precision. Only the inner circle of the backstop and the two rollers require higher precision, allowing the direct use of standard bearing outer rings, resulting in low cost and easy procurement, thus reducing system complexity and cost. While achieving high forward transmission efficiency, it also achieves bidirectional mechanical self-locking in reverse transmission, ensuring safety and reliability.

Description

Technical Field

[0001] This invention belongs to the field of mechanical transmission safety protection technology, specifically relating to a trapezoidal lead screw self-locking high-efficiency electric actuator. Background Technology

[0002] Existing electromechanical actuators mainly include ball screw type and trapezoidal screw type structures. Ball screw type has high transmission efficiency, but suffers from problems such as inability to self-lock in reverse and high cost. While trapezoidal screw type can achieve reverse self-locking, its forward transmission efficiency is generally below 30%, requiring a larger motor and resulting in higher overall cost. Other more complex additional self-locking mechanisms also suffer from low transmission efficiency and high cost. For example, adding a worm gear transmission mechanism to a ball screw actuator not only further reduces the overall transmission efficiency but also significantly increases the overall dimensions. Summary of the Invention

[0003] (a) Technical problems to be solved This invention proposes a trapezoidal lead screw self-locking high-efficiency electric actuator to solve the technical problem of how to achieve high forward transmission efficiency and bidirectional mechanical self-locking while simultaneously achieving a small profile and low cost.

[0004] (II) Technical Solution To address the aforementioned technical problems, this invention proposes a trapezoidal lead screw self-locking high-efficiency electric actuator. This trapezoidal lead screw self-locking high-efficiency electric actuator includes a housing, a motor, a pre-stage reduction mechanism, an intermediate transmission mechanism, a post-stage reduction mechanism, a bidirectional backstop, a trapezoidal lead screw, bearings, a nut, a push rod, a base hinge point, and a load hinge point; wherein... The motor and the bidirectional backstop are fixed to the outside of the housing; the inside of the housing is equipped with a front-stage reduction mechanism, an intermediate transmission mechanism, a rear-stage reduction mechanism, and bearings. The pre-reduction mechanism adopts a planetary reduction mechanism with a fixed internal gear ring, sun gear input, and frame output. The sun gear of the pre-reduction mechanism is fixedly connected to the output shaft of the motor, and the frame output end of the pre-reduction mechanism is fixedly connected to the input end of the intermediate transmission mechanism. The input and output ends of the pre-reduction mechanism are supported in the housing by bearings, and the output end is fixedly connected to the input half-shaft of the bidirectional backstop. Power is transmitted from the motor to the output half-shaft of the bidirectional backstop through the backstop mechanism located between the input half-shaft and the output half-shaft of the bidirectional backstop. The backstop mechanism is set in the hinged cylindrical space between the base hinge point and the housing, and the backstop mechanism occupies the middle part of the hinged cylindrical space. The rear reduction mechanism adopts a planetary reduction mechanism with a fixed internal gear ring, sun gear input, and frame output. The sun gear of the rear reduction mechanism is fixedly connected to the output half shaft of the double-acting backstop. The sun gear of the rear reduction mechanism passes through the center of the hollow structure at the output end of the intermediate transmission mechanism and meshes with the planet gear of the rear reduction mechanism. The frame output end of the rear reduction mechanism is fixedly connected to the rear end of the trapezoidal lead screw. The rear end of the trapezoidal lead screw is supported by a bearing; a nut is installed on the trapezoidal lead screw, and the inner helix of the nut and the outer helix of the lead screw form a trapezoidal lead screw pair. The front end face of the nut is fixedly connected to the rear end of the hollow push rod, and the front end of the push rod is provided with a load hinge fulcrum for connecting with the load.

[0005] Furthermore, the intermediate transmission mechanism adopts a chain and sprocket or a toothed belt mechanism.

[0006] Furthermore, the backstop mechanism adopts a double roller bidirectional backstop mechanism.

[0007] Furthermore, the bearings supporting the trapezoidal lead screw are angular contact bearings or tapered roller bearings.

[0008] Furthermore, the lead angle of the trapezoidal lead screw is 8°~25°.

[0009] Furthermore, the trapezoidal lead screw is lubricated with silicone oil.

[0010] Furthermore, the housing diameters of both the motor and the trapezoidal lead screw are Φ70mm.

[0011] Furthermore, the trapezoidal lead screw self-locking high-efficiency electric actuator has an overall thrust greater than 2.5 tons, a telescopic speed of 10 mm / s, and a reverse mechanical self-locking function.

[0012] (III) Beneficial Effects This invention proposes a trapezoidal lead screw self-locking high-efficiency electric actuator, comprising a housing, a motor, a pre-stage reduction mechanism, an intermediate transmission mechanism, a post-stage reduction mechanism, a bidirectional backstop, a trapezoidal lead screw, bearings, a nut, a push rod, a base hinge point, and a load hinge point. All components of this trapezoidal lead screw self-locking high-efficiency electric actuator employ structures with high transmission efficiency, achieving a total transmission efficiency exceeding 55%, significantly improving the overall thrust-to-volume ratio. Motor current can be greatly reduced, and most parts require only medium to low precision. Only the inner circle of the backstop and the two rollers require higher precision, allowing the direct use of standard bearing outer rings, resulting in low cost and easy procurement, thus reducing system complexity and cost. While achieving high forward transmission efficiency, it also achieves bidirectional mechanical self-locking in reverse transmission, ensuring safety and reliability. This invention enables high-efficiency forward output of push-pull force and reverse mechanical self-locking, and can be used in load lifting mechanisms to prevent the load from dragging the machine uncontrollably due to gravity, inertia, or other load forces when the machine loses power. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of the trapezoidal lead screw self-locking high-efficiency electric actuator of the present invention; Figure 2 This is a partial structural diagram of the trapezoidal lead screw self-locking high-efficiency electric actuator of the present invention.

[0014] In the diagram: 1-Load hinge fulcrum; 2-Push rod; 3-Trapezoidal lead screw; 4-Nut; 5-Bearing; 6-Box; 7-Double backstop output half-shaft; 8-Double backstop; 9-Base hinge fulcrum; 10-Backstop mechanism; 11-Double backstop input half-shaft; 12-Intermediate transmission mechanism; 13-Pre-stage reduction mechanism; 14-Motor; 15-Rear-stage reduction mechanism. Detailed Implementation

[0015] To make the objectives, contents, and advantages of the present invention clearer, the specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0016] This embodiment proposes a trapezoidal lead screw self-locking high-efficiency electric actuator, the structure of which is as follows: Figure 1 and 2 As shown, it mainly includes a housing 6, a motor 14, a front-stage reduction mechanism 13, an intermediate transmission mechanism 12, a rear-stage reduction mechanism 15, a bidirectional backstop 8, a trapezoidal lead screw 3, a bearing 5, a nut 4, a push rod 2, a base hinge 9, and a load hinge 1.

[0017] The housing 6 has a rectangular structure, and the motor 14 and the bidirectional backstop 8 are fixed to the outside of the housing 6. The inside of the housing 6 is equipped with a front-stage reduction mechanism 13, an intermediate transmission mechanism 12, a rear-stage reduction mechanism 15, and bearings 5.

[0018] The pre-reduction mechanism 13 is a planetary reduction mechanism with a fixed internal gear ring, sun gear input, and frame output. The sun gear of the pre-reduction mechanism 13 is fixedly connected to the output shaft of the motor 14, and the frame output end of the pre-reduction mechanism 13 is fixedly connected to the input end of the intermediate transmission mechanism 12. The intermediate transmission mechanism 12 uses a chain sprocket or toothed belt mechanism. The input and output chain (belt) pulleys are supported in the housing 6 by bearings. The output chain (belt) pulley is fixedly connected to the bidirectional backstop input half-shaft 11 of the bidirectional backstop 8. Power is transmitted from the motor 14 to the bidirectional backstop output half-shaft 7 through the backstop mechanism 10 located between the bidirectional backstop input half-shaft 11 and the bidirectional backstop output half-shaft 7. The backstop mechanism 10 is a double roller type bidirectional backstop mechanism, which is small in size and is set in the hinged cylindrical space between the base hinge point 9 and the housing 6. The backstop mechanism 10 occupies the middle part of the hinged cylindrical space.

[0019] The rear reduction mechanism 15 is a planetary reduction mechanism with a fixed internal gear ring, sun gear input, and frame output. The sun gear of the rear reduction mechanism 15 is fixedly connected to the output half-shaft 7 of the double-acting backstop. The sun gear of the rear reduction mechanism 15 passes through the center of the hollow structure of the output chain (belt) pulley of the intermediate transmission mechanism 12 and meshes with the planet gears of the rear reduction mechanism 15. The frame output end of the rear reduction mechanism 15 is fixedly connected to the rear end of the trapezoidal lead screw 3.

[0020] The rear end of the trapezoidal lead screw 3 is supported by a bearing 5. The bearing 5 is an angular contact bearing or a tapered roller bearing that can withstand both axial and radial forces.

[0021] A nut 4 is installed on the trapezoidal lead screw 3. The inner helix of the nut 4 and the outer helix of the lead screw 3 form a trapezoidal lead screw pair. The helix adopts a multi-start, large-lead design to ensure a transmission efficiency of not less than 70%. The front end face of the nut 4 is fixedly connected to the rear end of the hollow push rod 2. The front end of the push rod 2 is provided with a load hinge fulcrum 1 for connecting to the load.

[0022] When the motor 14 is powered on and rotates, the power is transmitted to the trapezoidal lead screw 3 through the front reduction mechanism 13, the intermediate transmission mechanism 12, the bidirectional backstop 8 and the rear reduction mechanism 15, which reduces the speed and increases the torque. The trapezoidal lead screw 3 drives the nut 4 to translate by rotating, and finally converts it into the telescopic motion power between the load hinge 1 and the base hinge 9, which drives the load to move.

[0023] The planetary transmission mechanism in the transmission chain has an efficiency of over 95%, the chain or belt transmission efficiency is close to 98%, the double roller bidirectional backstop 8 has a forward transmission efficiency of close to 98% while reverse transmission is completely self-locking, and the large lead trapezoidal screw 3 has a transmission efficiency of up to 70%. Therefore, under the conditions of achieving reverse transmission self-locking and a transmission ratio between the motor and the screw of not less than 80, the overall forward transmission efficiency of the total transmission ratio is not less than 55%. Because of its high efficiency and large transmission ratio characteristics, the entire mechanism can use a high-speed, low-torque brushed DC motor, thereby effectively reducing motor costs.

[0024] In this invention, the trapezoidal lead screw 3 adopts a large lead trapezoidal lead screw with a lead angle of 8°~25°, and is combined with an efficient lubrication method to reduce the coefficient of friction. The transmission efficiency of the trapezoidal lead screw is related to the tooth profile angle, helix angle, and coefficient of friction. The forward transmission efficiency of a reverse self-locking trapezoidal lead screw is usually less than 30%, while the large lead trapezoidal lead screw 3, by adopting a lubrication method such as silicone oil lubrication that can significantly reduce the coefficient of friction, can increase the transmission efficiency to 70% while still maintaining low cost, but at the same time losing the self-locking ability.

[0025] In this invention, a double-roller bidirectional backstop 8 arranged within the cylindrical body at the pivot point 9 of the base can achieve a forward transmission efficiency of nearly 98%, while the reverse transmission direction is completely mechanically self-locking. The input half-shaft 11 of the bidirectional backstop is fixedly connected to the output end chain (belt) pulley on the output wheel of the intermediate transmission mechanism 12. The output end chain (belt) pulley is hollow, allowing the sun gear of the intermediate transmission mechanism 12 to pass through and connect with the output half-shaft 7 of the bidirectional backstop. The intermediate transmission mechanism 12 employs a low-cost, high-efficiency transmission method such as a chain or toothed belt. A pre-stage reduction mechanism 13 is provided at the output shaft of the motor 14, which, together with the intermediate transmission mechanism 12, configures the overall transmission ratio of the entire mechanism.

[0026] The present invention is applied to a high-efficiency electric actuator with trapezoidal lead screw self-locking designed for lifting a certain load. The outer shell diameter of both the motor 14 and the trapezoidal lead screw 3 is Φ70mm. The overall thrust is greater than 2.5 tons, the extension speed is 10mm / s, and it has a reverse mechanical self-locking function, which can reliably self-lock a 3-ton load.

[0027] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A trapezoidal lead screw self-locking high-efficiency electric actuator, characterized in that, The trapezoidal lead screw self-locking high-efficiency electric actuator includes a housing, a motor, a pre-stage reduction mechanism, an intermediate transmission mechanism, a post-stage reduction mechanism, a bidirectional backstop, a trapezoidal lead screw, bearings, a nut, a push rod, a base hinge point, and a load hinge point; wherein... The motor and the bidirectional backstop are respectively fixed to the outside of the housing; the inside of the housing is equipped with a front-stage reduction mechanism, an intermediate transmission mechanism, a rear-stage reduction mechanism, and bearings; The pre-reduction mechanism is a planetary reduction mechanism with a fixed internal gear ring, sun gear input, and frame output. The sun gear of the pre-reduction mechanism is fixedly connected to the output shaft of the motor, and the frame output end of the pre-reduction mechanism is fixedly connected to the input end of the intermediate transmission mechanism. The input and output ends of the pre-reduction mechanism are supported in the housing by bearings, and the output end is fixedly connected to the input half-shaft of the bidirectional backstop. Power is transmitted from the motor to the output half-shaft of the bidirectional backstop through the backstop mechanism located between the input half-shaft and the output half-shaft of the bidirectional backstop. The backstop mechanism is set in the hinged cylindrical space between the base hinge point and the housing, and the backstop mechanism occupies the middle part of the hinged cylindrical space. The rear reduction mechanism is a planetary reduction mechanism with a fixed internal gear ring, sun gear input, and frame output. The sun gear of the rear reduction mechanism is fixedly connected to the output half shaft of the bidirectional backstop. The sun gear of the rear reduction mechanism passes through the center of the hollow structure at the output end of the intermediate transmission mechanism and meshes with the planet gear of the rear reduction mechanism. The frame output end of the rear reduction mechanism is fixedly connected to the rear end of the trapezoidal lead screw. The rear end of the trapezoidal lead screw is supported by a bearing; a nut is installed on the trapezoidal lead screw, and the inner helix of the nut and the outer helix of the lead screw form a trapezoidal lead screw pair; the front end face of the nut is fixedly connected to the rear end of the hollow push rod; the front end of the push rod is provided with a load hinge fulcrum for connecting with the load.

2. The trapezoidal lead screw self-locking high-efficiency electric actuator as described in claim 1, characterized in that, The intermediate transmission mechanism adopts a chain and sprocket or a toothed belt mechanism.

3. The trapezoidal lead screw self-locking high-efficiency electric actuator as described in claim 1, characterized in that, The backstop mechanism is a double roller bidirectional backstop mechanism.

4. The trapezoidal lead screw self-locking high-efficiency electric actuator as described in claim 1, characterized in that, The bearing supporting the trapezoidal lead screw is an angular contact bearing or a tapered roller bearing.

5. The trapezoidal lead screw self-locking high-efficiency electric actuator as described in claim 1, characterized in that, The lead angle of the trapezoidal lead screw is 8°~25°.

6. The trapezoidal lead screw self-locking high-efficiency electric actuator as described in claim 5, characterized in that, The trapezoidal lead screw is lubricated with silicone oil.

7. The trapezoidal lead screw self-locking high-efficiency electric actuator as described in claim 1, characterized in that, The outer casing diameter of both the motor and the trapezoidal lead screw is Φ70mm.

8. The trapezoidal lead screw self-locking high-efficiency electric actuator as described in claim 1, characterized in that, The trapezoidal lead screw self-locking high-efficiency electric actuator has an overall thrust greater than 2.5 tons, a telescopic speed of 10 mm / s, and a reverse mechanical self-locking function.

Images