A manual-electric switching device for electric actuator based on electromagnetic control

Abstract

The present invention discloses a manual-electric switching device for an electric actuator based on electromagnetic control, comprising: a housing, a handwheel assembly, an electromagnetic control assembly, an elastic device, and a transmission shaft. The handwheel assembly is assembled in the housing, and rotating the handwheel can drive the handwheel shaft to rotate, and the handwheel shaft can be disengaged or engaged with the transmission shaft by axial movement of the handwheel shaft; the electromagnetic switching assembly can adjust different relative positions with the handwheel assembly by switching the current on and off, thereby realizing switching between manual and electric states. In the manual state, the current in the electromagnetic control assembly is disconnected and the handwheel shaft is self-locked, and the handwheel assembly is engaged with the transmission shaft for manual operation; when the electric actuator is powered on, current is passed through the electromagnetic control assembly and it is activated, the self-locking of the handwheel shaft is eliminated, the handwheel assembly is disengaged and reset from the transmission shaft by the elastic device, the manual state becomes invalid, and it automatically switches to the electric state. The present invention provides a device that can realize switching between the manual and electric states of an electric actuator, which is effective and reliable.

Description

Technical Field

[0001] The present invention relates to the field of electric actuators, and in particular to a manual-electric switching device of an electric actuator based on electromagnetic control. Background Art

[0002] Electric actuators are a crucial component of industrial systems, primarily used to control the opening and closing of valves. They are mechatronic devices widely used in the hydropower, chemical, and petroleum industries. Generally, electric actuators actuate valves through an internal motor, which drives the output terminal through an internal transmission mechanism. However, due to the unique nature of actual operating conditions, electric actuators are often required to have a reliable manual-to-electric switching function, enabling manual operation in the event of a power outage and ensuring stable switching between manual and electric modes.

[0003] Currently, most of the manual-electric switching devices of electric actuators on the market have operational risks or defects. First, they cannot self-lock in the manual state, and the operator needs to provide a large operating force to maintain the manual state, which has certain operational difficulties and physical requirements; second, the manual state cannot be automatically exited and needs to be switched manually, which may cause the handwheel to rotate when the electric actuator is powered on again, causing safety hazards. Summary of the Invention

[0004] The purpose of the present invention is to solve the defects existing in the prior art and provide a manual-electric switching device for an electric actuator, which can effectively realize the functions of self-locking in the manual state and automatically exiting the manual state when switching to the electric state.

[0005] In order to achieve the above object, the technical solution provided by the present invention is as follows:

[0006] A manual-electric switching device for an electric actuator based on electromagnetic control comprises a housing, a handwheel assembly, an electromagnetic control assembly and a transmission shaft; the manual-electric switching device for an electric actuator of the present invention further comprises an elastic device;

[0007] Among them, the handwheel assembly includes a handwheel, a handwheel shaft, and a connecting sleeve. One end of the handwheel shaft is connected to the handwheel through a pin shaft, and the other end extends into the housing and is connected to the connecting sleeve through an elastic cylindrical pin;

[0008] The electromagnetic control assembly is coaxially mounted within the housing along with the handwheel shaft, and comprises a support tube, a limiting sleeve, a retaining frame, a magnetic steel ball, and an electromagnet. The limiting sleeve is fixedly mounted within the housing and sleeved around the outer circumference of the handwheel shaft, with its inner diameter gradually increasing from top to bottom. The retaining frame is sleeved between the handwheel shaft and the limiting sleeve, and is embedded with a magnetic steel ball that can roll freely within the retaining frame. The electromagnet is fixedly mounted within the housing via the support tube, between the elastic cylindrical pin and the retaining frame.

[0009] The elastic device includes an adjustment bracket, a primary spring, and a secondary spring. The adjustment bracket is fixedly connected to the connecting sleeve through an elastic cylindrical pin and a shaft retaining ring. The primary spring is sleeved on the handwheel shaft, and its two ends respectively abut against the retaining bracket and the electromagnet. The secondary spring is sleeved on the connecting sleeve, and its two ends respectively abut against the adjustment bracket and the housing. The primary and secondary springs are always in a compressed state.

[0010] Groove 2 and groove 1 are provided on the handwheel shaft from top to bottom; when the manual-electric switching device of the electric actuator is in the initial state, the connecting sleeve of the handwheel shaft is separated from the transmission shaft, one side of the magnetic steel ball is located in groove 1, and the other side is tangent to the inner wall of the limit sleeve; when the manual-electric switching device of the electric actuator is in the manual state, the handwheel shaft is connected to the transmission shaft through the connecting sleeve, one side of the magnetic steel ball is located in groove 2, and the other side is tangent to the inner wall of the limit sleeve; when the manual-electric switching device of the electric actuator is in the electric state, the magnetic steel ball is located below groove 1 of the handwheel shaft, and the connecting sleeve of the handwheel shaft is separated from the transmission shaft.

[0011] The present invention utilizes the design of the micro-flared mouth of the limiting sleeve, in conjunction with the design of the handwheel shaft groove and the first-level elastic device, to firmly lock the initial state and the manual state: in the initial state, the magnetic steel ball is stuck in the groove 1 of the handwheel shaft, and the upward thrust of the first-level spring on the retaining frame and the gradually shrinking inner diameter of the upper end of the limiting sleeve enable the magnetic steel ball to lock the handwheel shaft; in the manual state, the magnetic steel ball rolls with the handwheel shaft in the direction of the gradually increasing opening of the lower end of the limiting sleeve until it disengages from the groove 1 of the handwheel shaft, and the connecting sleeve of the handwheel shaft is engaged with the transmission shaft. At this time, the groove 2 on the handwheel shaft moves to the position of the groove 1 in the initial state, and the first-level spring pushes the retaining frame upward until the magnetic steel ball enters the groove 2 to achieve locking of the handwheel shaft.

[0012] At the same time, the electromagnetic control component cooperates with the elastic device to effectively realize the manual unlocking function in the electric state: when switching to the electric state, the electromagnet drives the magnetic steel ball to move toward the transmission shaft to the extreme position (when the pushing force of the primary spring is balanced with the magnetic field force). In this state, the magnetic steel ball escapes from the second groove of the handwheel shaft, the self-locking of the handwheel shaft disappears, the handwheel shaft can slide freely, and the secondary spring pushes the handwheel shaft to move away from the transmission shaft. At this time, the spline of the connecting sleeve and the output shaft is disengaged, and the manual state is released.

[0013] Furthermore, the shell includes an upper shell and a lower shell connected by fasteners, and an O-ring is provided between the upper shell and the lower shell; the handwheel shaft is supported by the upper shell; and the support cylinder is fixedly installed in the lower shell.

[0014] Furthermore, the upper shell is processed with a frame position and a bearing position, which are respectively installed with a skeleton oil seal and a deep groove ball bearing; the handwheel shaft is positioned and supported by the deep groove ball bearing; the lower shell is processed with a limit groove, and the support tube is installed and fixed through the limit groove; the limit sleeve is placed in the support tube and is tightened by the lower shell.

[0015] The O-ring and the skeleton oil seal between the upper and lower shells are used to effectively seal the cavity inside the shell.

[0016] Furthermore, a plurality of magnetic steel balls are provided and evenly distributed around the handwheel shaft. By tightening the plurality of magnetic steel balls, the handwheel shaft is prevented from moving in the opposite direction, and the manual shaft is effectively self-locked in the manual state.

[0017] Furthermore, the inner hole of the connecting sleeve is processed with splines, which mesh with the splines on the transmission shaft to transmit torque.

[0018] Furthermore, the length of the elastic cylindrical pin is greater than the outer diameter of the connecting sleeve.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] The present invention effectively realizes the functional requirements that the electric actuator is self-locking in the manual state during the manual-electric switching process, and automatically exits the manual state when switching to the electric state. Specifically, when the working state is switched to manual, the electromagnet is powered off, the magnetic field disappears, the handwheel shaft is pushed in through the handwheel, and the magnetic steel ball in the retaining frame moves from groove one to groove two on the handwheel shaft. The multiple magnetic steel balls are tightened to prevent the handwheel shaft from moving in the opposite direction, thereby achieving self-locking in the manual state. The operator does not need to continue to keep the handwheel pushed in to perform manual operation. When the working state is switched from manual to electric, the electromagnet is immediately powered on and generates a magnetic field. The retaining frame and the magnetic steel ball move along the handwheel shaft toward the electromagnet. The self-locking state of the handwheel shaft is immediately released. The secondary spring is released and simultaneously pushes the handwheel shaft to move away from the transmission shaft. The handwheel assembly is reset, the connecting sleeve is disengaged from the transmission shaft, and the manual state is automatically exited. No human operation is required during the switching process.

[0021] The invention of a manual-electric switching device for an electric actuator based on electromagnetic control can be widely used in electric actuators, effectively realizing self-locking in the manual state and automatic exit from the manual state when switching to the electric state, which is of great significance to ensuring the reliability and safety of the operation and use of the electric actuator. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a structural diagram of the manual-electric switching device of the electric actuator based on electromagnetic control of the present invention when it is in an initial state;

[0023] Figure 2 for Figure 1 A partial enlarged view of point Ⅰ in the middle;

[0024] Figure 3 It is a structural diagram of the manual state switching device of the electric actuator based on electromagnetic control of the present invention;

[0025] Figure 4 for Figure 3 A partial enlarged view of the middle II;

[0026] Figure 5 This is a structural diagram of the manual-electric switching device of the electric actuator based on electromagnetic control of the present invention when it is in manual mode;

[0027] Figure 6 for Figure 5 A partial enlarged view of point III in the middle;

[0028] Figure 7 This is a structural diagram of the manual-electric switching device of the electric actuator based on electromagnetic control of the present invention when it is in the electric state;

[0029] Figure 8 for Figure 7 A partial enlarged view of point IV in the middle.

[0030] In the figure, 1-handwheel, 2-pin shaft, 3-handwheel shaft, 301-groove two, 302-groove one, 4-upper housing, 5-lower housing, 6-skeleton oil seal, 7-deep groove ball bearing, 8-O-ring, 9-support cylinder, 10-limiting sleeve, 11-retaining frame, 12-magnetic steel ball, 13-primary spring, 14-electromagnet, 15-elastic cylindrical pin, 16-adjusting bracket, 17-shaft retaining ring, 18-connecting sleeve, 19-secondary spring, 20-drive shaft. DETAILED DESCRIPTION

[0031] The following describes in detail embodiments of the present invention, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0032] In the description of the present invention, it should be understood that terms such as "upper," "lower," "length," "push," "push out," "axial," "tangent," and "gap" indicate positions or relationships based on those shown in the accompanying drawings. These terms are intended solely to facilitate and simplify the description of the present invention and are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0033] In addition, features defined as "primary" or "secondary" may explicitly or implicitly include one or more of these features.

[0034] In the present invention, unless otherwise expressly specified or limited, terms such as "install," "connect," "detach," "fix," and "place" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in the present invention based on the specific circumstances.

[0035] like Figure 1-8 As shown, the present invention adopts a manual-electric switching device of an electric actuator based on electromagnetic control, which includes a housing, a handwheel assembly, an electromagnetic control assembly, an elastic device and a transmission shaft.

[0036] The shell includes an upper shell 4 and a lower shell 5, with a cavity inside. The upper shell 4 and the lower shell 5 are connected by fasteners; the upper shell 4 is processed with a skeleton position and a bearing position for installing the skeleton oil seal 6 and the deep groove ball bearing 7; the lower shell 5 is processed with a limiting groove for installing and fixing the support tube 9.

[0037] The handwheel assembly includes a handwheel 1, a handwheel shaft 3, and a connecting sleeve 18. One end of the handwheel shaft is connected to the handwheel through a pin shaft 2, and the other end is connected to the connecting sleeve 18 through an elastic cylindrical pin 15; the handwheel shaft 3 is positioned and supported by a deep groove ball bearing 7 in the upper shell 4, and the handwheel shaft 3 passes through the upper skeleton oil seal 6 of the upper shell and the O-ring 8 between the upper and lower shells to achieve sealing of the internal cavity; pushing the handwheel 1 causes the handwheel shaft 3 to move axially, and rotating the handwheel 1 can drive the handwheel shaft 3 and the connecting sleeve 18 to rotate, and transmit the torque to the connecting sleeve 18 for output. At the same time, a spline is machined in the inner hole of the connecting sleeve, which can engage with the spline on the drive shaft 20 to transmit torque; groove 1 302 and groove 2 301 are machined on the handwheel shaft 3 to achieve self-locking and switching between manual and electric states.

[0038] The electromagnetic control component includes a support tube 9, a limit sleeve 10, a retaining frame 11, a magnetic steel ball 12 and an electromagnet 14. The electromagnetic control component is installed coaxially with the handwheel shaft 3. The electromagnet 14 is fixedly placed at the bottom of the support tube 9. A plurality of evenly distributed magnetic steel balls 12 are placed in the retaining frame 11. The inner wall of the limit sleeve 10 is designed to have a gradually increasing opening. Its main function is to drive the magnetic steel balls 12 and the retaining frame 11 to move up and down along the handwheel shaft 3 toward the electromagnet through the magnetic field generated by the on and off of the current in the electromagnet 14 under different conditions; at the same time, the support tube 9 is installed in the limit groove of the lower shell to prevent it from moving downward, and the limit sleeve 10 is placed in the support tube 9 and is pressed by the upper shell to prevent it from moving upward.

[0039] The elastic device includes an adjusting bracket 16, a primary spring 13 and a secondary spring 19. The adjusting bracket 16 is fixedly connected to the connecting sleeve 18 through an elastic cylindrical pin 15 and a shaft retaining ring 17. The main function of the primary spring is to press against the retaining bracket in the manual state to achieve self-locking of the handwheel shaft. The main function of the secondary spring is to push the handwheel assembly to reset when switching between manual and electric modes.

[0040] like Figure 1 、 Figure 2 As shown, when the present invention is in its initial state, there is no pushing force on the handwheel 1, no current flows through the electromagnet 14, and the primary spring 13 is in a compressed state, generating an elastic force that presses against the retaining frame 11. Because the retaining frame 11 is located in the limiting sleeve 10, the limiting sleeve 10 is now pressed against the upper shell 4 and the limiting sleeve presses against the support tube 9, ensuring that the limiting sleeve 10 and the support tube 9 cannot move axially and that the retaining frame 11 cannot move further upward. The evenly distributed magnetic steel balls 12 in the retaining frame are located on one side in the groove 1 302 on the handwheel shaft 3 and on the other side tangent to the inner wall of the limiting sleeve 10. At the same time, the secondary spring 19 is in a compressed state, generating an elastic force that presses against the handwheel assembly. Because the inner wall of the limiting sleeve 10 is designed with a gradually increasing opening that gradually decreases in the direction away from the transmission shaft, the magnetic steel balls 12 are unable to continue to move toward the inner wall of the limiting sleeve 10 and are also unable to move away from the transmission shaft 20. Therefore, the multiple magnetic steel balls 12 will tighten the handwheel shaft. In addition, the upper end surface of the connecting sleeve 18 abuts against the lower end surface of the support tube 9, which can also prevent the handwheel shaft 3 from moving away from the transmission shaft 20. At this time, the handwheel assembly is in the initial state, and the connecting sleeve 18 is disengaged from the splines on the transmission shaft 20.

[0041] like Figure 3 、 Figure 4 As shown, when the present invention is in the manual switching state, no current flows in the electromagnet 14, and a downward pushing force is applied to the handwheel 1. The handwheel shaft 3 moves toward the transmission shaft 20 under the influence of the pushing force. At this time, the primary spring 13 is in a compressed state and presses against the retaining frame 11. The magnetic steel ball 12 and the handwheel shaft 3 begin to move relative to each other. The magnetic steel ball 12 is squeezed toward the side close to the inner wall of the limit sleeve 10 and tends to break away from the groove 302 on the handwheel shaft. At the same time, because the inner wall of the limit sleeve 10 is designed to have a gradually increasing opening, the magnetic steel ball will roll along the inner wall of the limit sleeve in the direction of the increasing opening of the limit sleeve until the magnetic steel ball 12 escapes from the groove 302 on the handwheel shaft and is tangent to the inner wall of the limit sleeve and the handwheel shaft. The primary spring 13 is further compressed.

[0042] The hand wheel shaft continues to move toward the transmission shaft until the connecting sleeve 18 is engaged with the spline on the transmission shaft 20. At this time, the present invention is in a manual state.

[0043] like Figure 5 、 Figure 6As shown, when the present invention is in the manual state, the groove 2 301 on the handwheel shaft moves to the position of the groove 1 302 in the initial state. Under the action of the spring force of the primary spring 13, the retaining frame 11 with the magnetic steel ball is pushed to move in the direction away from the transmission shaft 20 and finally the magnetic steel ball enters the groove 2 301. Combined with the above description of each component in the initial state, similarly, at this time, multiple magnetic steel balls will tighten the handwheel shaft to prevent the handwheel shaft from moving away from the transmission shaft, thereby realizing self-locking in the manual state.

[0044] When the present invention is in the manual state, the electric actuator is powered on and the electromagnet can be powered at the same time, and the present invention can automatically switch and enter the electric state.

[0045] like Figure 7 、 Figure 8 As shown, when the present invention is in the electric state, current flows into the electromagnet 14 and immediately generates a magnetic field. Under the action of the magnetic field, the magnetic steel ball 12 drives the retaining frame 11 to move toward the transmission shaft 20 and eventually to the limit position. The magnetic steel ball escapes from the second groove 301 on the handwheel shaft and becomes tangent to the handwheel shaft. Because the inner wall of the limit sleeve is designed to be a gradually increasing opening, which gradually increases in the direction close to the transmission shaft, there is a gap between the magnetic steel ball 12 and the inner wall of the limit sleeve 10 at this time. The self-locking of the handwheel shaft 3 disappears, and the handwheel shaft 3 can slide freely in the magnetic steel ball and the retaining frame. The secondary spring 19 is released, pushing the handwheel assembly to move away from the transmission shaft and eventually to the corresponding position in the initial state. Combined with the above description of each component in the initial state, because the upper end face of the connecting sleeve 18 is now against the lower end face of the support tube 9, it can be ensured that the handwheel assembly cannot move further away from the transmission shaft. At this time, the connecting sleeve 18 is disengaged from the spline on the transmission shaft 20, and the manual state is released.

[0046] When the present invention is in the electric state, the electric actuator is powered off, the current in the electromagnet 14 is disconnected, the magnetic field disappears, and the primary spring 13 is released. Under the action of the spring force, the retaining frame 11 with the magnetic steel ball 12 is pushed away from the transmission shaft, and finally the magnetic steel ball 12 enters the groove 302 of the handwheel shaft, and the device returns to its initial state.

[0047] The above description is only one embodiment of the present invention, which is only used to help understand the present invention and is not intended to limit the present invention. For those skilled in the art of the present invention, simple deductions, modifications or substitutions based on the concept of the present invention are all within the scope of protection of the present invention.

Claims

1. A manual-electric switching device for an electric actuator based on electromagnetic control, comprising a housing, a handwheel assembly, an electromagnetic control assembly and a transmission shaft; characterized in that: The electric actuator manual electric switching device also includes an elastic device; The handwheel assembly includes a handwheel, a handwheel shaft, and a connecting sleeve. One end of the handwheel shaft is connected to the handwheel through a pin, and the other end extends into the housing and is connected to the connecting sleeve through an elastic cylindrical pin. The electromagnetic control assembly is coaxially mounted within the housing with the handwheel shaft, and comprises a support tube, a limiting sleeve, a retaining frame, a magnetic steel ball, and an electromagnet; the limiting sleeve is fixedly mounted within the housing and sleeved around the outer circumference of the handwheel shaft, with its inner diameter gradually increasing from top to bottom; the retaining frame is sleeved between the handwheel shaft and the limiting sleeve, and is embedded with a magnetic steel ball that can roll freely within the retaining frame; the electromagnet is fixedly mounted within the housing, between the elastic cylindrical pin and the retaining frame, via the support tube; The elastic device includes an adjustment bracket, a primary spring, and a secondary spring. The adjustment bracket is fixedly connected to the connecting sleeve through an elastic cylindrical pin and a shaft retaining ring. The primary spring is sleeved on the handwheel shaft, and its two ends respectively abut against the retaining bracket and the electromagnet. The secondary spring is sleeved on the connecting sleeve, and its two ends respectively abut against the adjustment bracket and the housing. The primary spring and the secondary spring are always in a compressed state. The handwheel shaft is provided with groove 2 and groove 1 from top to bottom; when the manual-electric switching device of the electric actuator is in the initial state, the connecting sleeve of the handwheel shaft is separated from the transmission shaft, one side of the magnetic steel ball is located in groove 1, and the other side is tangent to the inner wall of the limit sleeve; when the manual-electric switching device of the electric actuator is in the manual state, the handwheel shaft is connected to the transmission shaft through the connecting sleeve, one side of the magnetic steel ball is located in groove 2, and the other side is tangent to the inner wall of the limit sleeve; when the manual-electric switching device of the electric actuator is in the electric state, the magnetic steel ball is located below groove 1 of the handwheel shaft, and the connecting sleeve of the handwheel shaft is separated from the transmission shaft.

2. The manual-electric switching device of the electric actuator according to claim 1, characterized in that: The housing includes an upper housing and a lower housing connected by fasteners, and an O-ring is provided between the upper housing and the lower housing; the handwheel shaft is supported by the upper housing; and the support cylinder is fixedly installed in the lower housing.

3. The manual-electric switching device of the electric actuator according to claim 2, characterized in that: The upper shell is processed with a skeleton position and a bearing position, which are respectively installed with a skeleton oil seal and a deep groove ball bearing; the handwheel shaft is positioned and supported by the deep groove ball bearing; the lower shell is processed with a limiting groove, and the support tube is installed and fixed through the limiting groove; the limiting sleeve is placed in the support tube and is pressed by the lower shell.

4. The manual-electric switching device for an electric actuator according to claim 1, characterized in that: There are multiple magnetic steel balls, which are evenly distributed around the handwheel shaft.

5. The manual-electric switching device for an electric actuator according to claim 1, characterized in that: The inner hole of the connecting sleeve is processed with splines, which mesh with the splines on the transmission shaft.

6. The manual-electric switching device for an electric actuator according to claim 1, characterized in that: The length of the elastic cylindrical pin is greater than the outer diameter of the connecting sleeve.

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