Electric actuator manual and electric switching device based on electromagnetic control

Abstract

The invention discloses a manual and electric switching device of an electric actuator based on electromagnetic control. The manual and electric switching device comprises a shell, a hand wheel assembly, an electromagnetic control assembly, an elastic device and a transmission shaft. The hand wheel assembly is assembled in the shell, a hand wheel shaft can be driven to rotate by rotating a hand wheel, and the hand wheel shaft can be disengaged from or engaged with the transmission shaft through axial movement of the hand wheel shaft. And the electromagnetic switching assembly can realize switching between a manual state and an electric state by adjusting different relative positions of the electromagnetic switching assembly and the hand wheel assembly through current on-off. In the manual state, current in the electromagnetic control assembly is disconnected and self-locked with the hand wheel shaft, the hand wheel assembly is meshed with the transmission shaft, and manual operation is carried out. The electric actuator is powered on, the electromagnetic control assembly is powered on and acts, self-locking of the hand wheel shaft is eliminated, the hand wheel assembly and the transmission shaft are disengaged and reset through the elastic device, and the manual state fails and is automatically switched into the electric state. The invention provides a device capable of realizing the switching between the manual state and the electric state of the electric actuator, and the device is effective and reliable.

Description

Technical Field

[0001] The 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 an important part of industrial systems. They are mainly used to control the opening and closing and adjustment of valves. They are mechatronic devices widely used in hydropower, chemical, petroleum and other fields. Generally, electric actuators mainly drive valves by driving the output end through the internal motor through the internal transmission mechanism. However, due to the particularity of actual working conditions, electric actuators are usually required to have a reliable manual-electric switching function, that is, manual operation can be performed in the event of a power outage, and stable switching between manual and electric states can be achieved.

[0003] At present, 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 is required to provide a large operating force to maintain the manual state, which has certain operating 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 to 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 hand-to-electric switching device for an electric actuator based on electromagnetic control comprises a housing, a hand wheel assembly, an electromagnetic control assembly and a transmission shaft; the hand-to-electric switching device for an electric actuator of the present invention further comprises an elastic device;

[0007] 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.

[0008] The electromagnetic control assembly is coaxially installed in the housing with the handwheel shaft, and includes a support tube, a limit sleeve, a retaining frame, a magnetic steel ball and an electromagnet; the limit sleeve is fixed in the housing and sleeved on the outer peripheral side of the handwheel shaft, and the inner diameter gradually increases from top to bottom; the retaining frame is sleeved between the handwheel shaft and the limit sleeve, and a magnetic steel ball is embedded thereon and can roll freely in the retaining frame; the electromagnet is fixed in the housing through the support tube, at a position between the elastic cylindrical pin and the retaining frame;

[0009] The elastic device includes an adjusting bracket, a primary spring and a secondary spring. The adjusting bracket is fixedly connected with 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 are respectively against the retaining frame and the electromagnet; the secondary spring is sleeved on the connecting sleeve, and its two ends are respectively against the adjusting bracket and the housing; the primary spring and the secondary spring are always in a compressed state;

[0010] A groove 2 and a groove 1 are provided on the handwheel shaft from top to bottom in sequence; when the hand-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 the groove 1, and the other side is tangent to the inner wall of the limit sleeve; when the hand-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 the groove 2, and the other side is tangent to the inner wall of the limit sleeve; when the hand-electric switching device of the electric actuator is in the electric state, the magnetic steel ball is located below the 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 groove of the handwheel shaft and the primary elastic device, to firmly lock the initial state and the manual state: in the initial state, the magnetic steel ball is inserted into the groove one of the handwheel shaft, and the primary spring pushes the retaining frame upward and the gradually shrinking inner diameter of the upper end of the limiting sleeve causes the magnetic steel ball to lock the handwheel shaft; in the manual state, the magnetic steel ball rolls along with the handwheel shaft in the direction of the gradually increasing opening of the lower end of the limiting sleeve until it escapes from the groove one of the handwheel shaft, until the connecting sleeve of the handwheel shaft is meshed and connected with the transmission shaft, at which point the groove two on the handwheel shaft moves to the position of the groove one in the initial state, and at this point the primary spring pushes the retaining frame upward until the magnetic steel ball enters the groove two 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 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.

[0014] Furthermore, the upper shell is processed with a frame position and a bearing position, and a frame oil seal and a deep groove ball bearing are installed respectively; 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 by the limit groove; the limit sleeve is placed in the support tube and is pressed by the lower shell.

[0015] The sealing of the cavity inside the shell is effectively achieved by the O-ring and the skeleton oil seal between the upper and lower shells.

[0016] Furthermore, a plurality of magnetic steel balls are provided and evenly distributed around the hand wheel shaft. By tightening the plurality of magnetic steel balls, the hand wheel 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 a spline, which meshes with the spline 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 the manual state is automatically exited when the electric state is switched. 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. Multiple magnetic steel balls are tightened to prevent the handwheel shaft from moving in the opposite direction, so as to achieve 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 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 discloses a manual-electric switching device for an electric actuator based on electromagnetic control, which can be widely used in electric actuators, effectively realizing self-locking in the manual state and automatic exiting of the manual state when switching to the electric state, and is of great significance for ensuring the reliability and safety of the operation and use of the electric actuator. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

[0028] Figure 7 It is a structural schematic diagram of the hand-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 shell, 5-lower shell, 6-skeleton oil seal, 7-deep groove ball bearing, 8-O-ring, 9-support cylinder, 10-limit 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-transmission shaft. DETAILED DESCRIPTION

[0031] The embodiments of the present invention are described in detail below, 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 only used to explain the present invention, and cannot be understood as limiting the present invention.

[0032] In the description of the present invention, it should be understood that the terms "upper", "lower", "length", "push-in", "push-out", "axial", "tangent", "gap" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

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

[0034] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "detach", "fix", "place" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] like Figure 1-8 As shown, the present invention adopts a hand-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 frame position and a bearing position for installing a frame oil seal 6 and a 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 an upper skeleton oil seal 6 of the upper shell and an 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 transmission shaft 20 to transmit torque; a groove 1 302 and a 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 in different states through the magnetic field generated by the on and off of the current in the electromagnet 14; 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 primary spring mainly functions to resist the retaining frame in the manual state to achieve self-locking of the handwheel shaft. The secondary spring mainly functions 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 the initial state, there is no pushing force on the hand wheel 1, no current flows in the electromagnet 14, and the primary spring 13 is in a compressed state, generating elastic force and resisting the retaining frame 11. Because the retaining frame 11 is located in the limiting sleeve 10, the limiting sleeve 10 is pressed by the upper shell 4 and the limiting sleeve presses the support tube 9 at this time, which can ensure that the limiting sleeve 10 and the support tube 9 cannot move axially and the retaining frame 11 cannot continue to move upward. One side of the evenly distributed magnetic steel balls 12 in the retaining frame is located in the groove 1 302 on the hand wheel shaft 3, and the other side is tangent to the inner wall of the limiting sleeve 10; at the same time, the secondary spring 19 is in a compressed state, generating elastic force and resisting the hand wheel assembly. Because the inner wall of the limit sleeve 10 is designed to be a gradually increasing opening, which gradually decreases in the direction away from the transmission shaft, the magnetic steel ball 12 cannot continue to move toward the inner wall of the limit sleeve 10, and cannot move away from the transmission shaft 20. Therefore, 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 supporting tube 9, which can 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 splines on the connecting sleeve 18 and the transmission shaft 20 are disengaged.

[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 produce relative movement. The magnetic steel ball 12 is squeezed toward the side close to the inner wall of the limiting sleeve 10 and has a tendency to break away from the groove 302 on the handwheel shaft. At the same time, because the inner wall of the limiting sleeve 10 is designed as a gradually increasing opening, the magnetic steel ball will roll along the inner wall of the limiting sleeve in the direction of the increasing opening of the limiting 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 limiting sleeve and the handwheel shaft, and 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 in engagement with the splines on the transmission shaft 20, at which 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, and 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 a manual state, the electric actuator is powered on, and power can be supplied to the electromagnet at the same time, and the present invention can automatically switch and enter an electric state.

[0045] like Figure 7 , Figure 8 As shown, when the present invention is in the electric state, there is a current flowing into the electromagnet 14 and a magnetic field is immediately generated. The magnetic steel ball 12 will drive the retaining frame 11 to move toward the transmission shaft 20 under the action of the magnetic field and finally reach the limit position. The magnetic steel ball escapes from the groove 2 301 on the handwheel shaft and is tangent to the handwheel shaft. Because the inner wall of the limit sleeve is designed to be a gradually increasing opening, it gradually increases in the direction close to the transmission shaft. Therefore, at this time, there is a gap between the magnetic steel ball 12 and the inner wall of the limit sleeve 10, and the self-locking of the handwheel shaft 3 disappears. 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 finally 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 at this time is 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 to move 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, some simple deductions, modifications or substitutions made according to the concept of the present invention are all within the protection scope 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 comprises a handwheel, a handwheel shaft and a connecting sleeve, wherein 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 installed in the housing with the handwheel shaft, and includes a support tube, a limit sleeve, a retaining frame, a magnetic steel ball and an electromagnet; the limit sleeve is fixedly arranged in the housing and sleeved on the outer peripheral side of the handwheel shaft, and the inner diameter gradually increases from top to bottom; the retaining frame is sleeved between the handwheel shaft and the limit sleeve, and a magnetic steel ball is embedded thereon, and can roll freely in the retaining frame; the electromagnet is fixedly arranged in the housing, between the elastic cylindrical pin and the retaining frame, through the support tube; The elastic device comprises an adjusting bracket, a primary spring and a secondary spring, wherein the adjusting bracket is fixedly connected with the connecting sleeve through an elastic cylindrical pin and a shaft retaining ring; the primary spring is sleeved on the hand wheel shaft, and its two ends are respectively against the retaining frame and the electromagnet; the secondary spring is sleeved on the connecting sleeve, and its two ends are respectively against the adjusting 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 in sequence from top to bottom; when the hand-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 hand-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 hand-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 electric actuator manual-electric switching device according to claim 1, characterized in that: The housing comprises an upper housing and a lower housing connected by fasteners, an O-ring is provided between the upper housing and the lower housing; the hand wheel shaft is supported by the upper housing; 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 frame position and a bearing position, and a frame oil seal and a deep groove ball bearing are installed respectively; 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 by the limiting groove; the limiting sleeve is placed in the support tube and is pressed by the lower shell.

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

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

Images