Electric straight stroke valve actuator

Abstract

The invention relates to the technical field of valves, in particular to an electric straight stroke valve actuator which comprises a shell, a motor, a screw, a moving ring and balls, the motor is arranged on the upper portion of the shell, the screw is coaxially connected with an output shaft of the motor, the moving ring is sleeved with the shell, a transmission groove is formed in the inner circumferential wall of the moving ring, and the head end and the tail end of the transmission groove are communicated; the transmission groove comprises a spiral groove part and a communication groove part, and the section size of the spiral groove part is matched with the section size of a thread groove of the screw rod. The ball and the spiral elastic strip are arranged, compared with a gear reducing mechanism such as a worm gear and a worm, the screw and the movable ring do not shake relative to each other when the screw conducts power input, in this way, return stroke errors do not occur, it can be guaranteed that the acting force can be accurately controlled when the valve plate of the valve is closed, and the service life of the valve is prolonged. The problem that the pressure between the valve plate and the valve cavity of the valve is too large or too small is solved.

Description

Technical Field

[0001] The invention relates to the technical field of valves, and in particular to an electric linear stroke valve actuator. Background Art

[0002] Valves are mainly divided into two types according to their stroke type, namely linear stroke valves and angular stroke valves. Common linear stroke valves include stop valves, gate valves and diaphragm valves, all of which work by moving the valve core or closing member in a straight line to control the flow of fluid. In the prior art, electric motors are often used as power sources, and the rotation of the motor is converted into linear motion of the valve stem through a reduction mechanism (such as a worm gear). However, when a gear reduction mechanism such as a worm gear is used for transmission (taking a worm gear transmission as an example), in order to ensure that the worm gear can rotate smoothly, a certain side clearance (i.e., tooth side clearance) is usually left in the design, so that a certain degree of return error will occur, which manifests as obvious shaking under some working conditions, making it difficult to accurately control the force of the valve plate when the valve is closed. Summary of the invention

[0003] Based on this, it is necessary to provide an electric linear stroke valve actuator to solve the problem that the force when the valve plate of the valve is closed is difficult to accurately control.

[0004] The above purpose is achieved through the following technical solutions: An electric linear valve actuator comprises: shell; A motor, which is arranged at the upper part of the housing; A screw rod, wherein the screw rod is coaxially connected to an output shaft of the motor; A moving ring is sleeved in the outer shell and can move along its own axis. A transmission groove is provided on the inner circumferential wall of the moving ring. The transmission groove is connected at both ends. The transmission groove includes a spiral groove part and a connecting groove part. The cross-sectional size of the spiral groove part is adapted to the cross-sectional size of the thread groove of the screw. Balls, there are multiple balls, and the multiple balls can be closely arranged along the transmission groove, and the balls rolling into the spiral groove part cooperate with the thread groove of the screw; A spiral spring bar, the spiral spring bar is arranged in the spiral groove part, and the spiral spring bar is configured to push the ball rolling into the spiral groove part to cling to the thread groove of the screw; A transmission sleeve is coaxially and fixedly connected with the moving ring, and one end of the transmission sleeve away from the moving ring is connected with the valve stem of the valve.

[0005] Preferably, the cross-sectional shape of the spiral groove portion is the same as the cross-sectional shape of the spiral groove of the screw, and both are V-shaped.

[0006] Preferably, the movable ring is provided with an installation cavity, the installation cavity is connected with the communicating groove, an electromagnetic component is provided in the installation cavity, the magnetism of the electromagnetic component can be changed, a pressure sensor is provided in the valve, and the pressure sensor is electrically connected with the electromagnetic component; The ball is magnetic; The electromagnetic component is configured so that when the pressure value detected by the pressure sensor is greater than a preset value, the electromagnetic component is activated, and the magnetism of the electromagnetic component changes once every preset time period; When the magnetism of the electromagnetic component is opposite to that of the ball, the ball moves from the connecting groove to the installation cavity under the magnetic attraction of the electromagnetic component; When the magnetism of the electromagnetic assembly is the same as that of the ball, the ball moves from the installation cavity back to the communicating groove portion under the magnetic effect of the electromagnetic assembly.

[0007] Preferably, the electromagnetic assembly includes an electromagnet and an elastic member, there are two elastic members, the two elastic members are spaced apart in the installation cavity, one end of the two elastic members away from the installation cavity is fixedly connected to the electromagnet, and the elastic member is used to prevent the electromagnet from moving along the length direction of the installation cavity.

[0008] Preferably, guide blocks are provided at two connecting positions of the spiral groove portion and the connecting groove portion, and the guide blocks are used to guide the movement of the balls.

[0009] Preferably, the movable ring and the transmission sleeve are threadedly matched to achieve a coaxial fixed connection.

[0010] Preferably, one end of the transmission sleeve away from the moving ring is threadedly connected with a connecting end, and the end of the transmission sleeve away from the moving ring is connected to the valve stem of the valve through the connecting end.

[0011] Preferably, a support ring is provided at one end of the screw away from the motor, and the outer diameter of the support ring is matched with the inner diameter of the transmission sleeve.

[0012] Preferably, a connecting hole is provided at the lower portion of the shell, and the diameter of the connecting hole is matched with the diameter of the valve stem of the valve.

[0013] Preferably, a plurality of threaded holes are provided at equal intervals in the circumferential direction of the connecting hole at the lower portion of the housing, and the threaded holes correspond one-to-one to the threaded holes on the flange surface of the valve and are connected by bolts.

[0014] The beneficial effects of the present invention are: The present invention is provided with a ball and a spiral spring bar. Compared with a gear reduction mechanism such as a worm gear, when the screw in the present invention inputs power, there will be no relative shaking between the screw and the moving ring, so there will be no return error, thereby ensuring that the force when the valve plate of the valve is closed can be accurately controlled to avoid the problem of excessive or insufficient pressure between the valve plate and the valve chamber of the valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an overall schematic diagram of an electric linear valve actuator of the present invention; Figure 2 A side view of an electric straight-stroke valve actuator of the present invention; Figure 3 for Figure 2 Middle AA section view; Figure 4 for Figure 3 Schematic diagram of the enlarged structure at B in the middle; Figure 5 An exploded view of an electric linear valve actuator of the present invention; Figure 6 It is a structural schematic diagram of a moving ring in an electric linear valve actuator of the present invention; Figure 7 for Figure 6 Middle CC section view; Figure 8 It is a structural schematic diagram of a screw in an electric linear valve actuator of the present invention; Fig. 9 for Figure 8 Schematic diagram of the enlarged view at D in the middle.

[0016] in: 100, housing; 110, connecting hole; 120, threaded hole; 200, motor; 300, screw; 310, support ring; 400, moving ring; 410, transmission groove; 411, spiral groove portion; 412, connecting groove portion; 420, mounting cavity; 430, guide block; 440, limit block; 500, ball bearing; 600, spiral spring bar; 700, transmission sleeve; 710, connection end; 800, electromagnetic assembly; 810, electromagnet; 820, elastic member. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0018] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in the present invention, unless otherwise specified, include direct and indirect connections (couplings). In the description of the present invention, it should be understood that the orientations or positional relationships indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientations or positional relationships shown in the accompanying 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 element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0019] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0020] like Figures 1 to 9As shown, an electric linear valve actuator includes a housing 100, a motor 200, a screw 300, a moving ring 400 and a ball 500. The motor 200 is arranged at the upper part of the housing 100, the screw 300 is coaxially connected with the output shaft of the motor 200, and the moving ring 400 is sleeved in the housing 100. Specifically, the moving ring 400 can move along the axis of the moving ring 400 relative to the housing 100. A transmission groove 410 is opened on the inner peripheral wall of the moving ring 400. The transmission groove 410 is connected at both ends. The transmission groove 410 includes a spiral groove part 411 and a connecting groove part 412. The cross-sectional size of the spiral groove part 411 is adapted to the cross-sectional size of the thread groove of the screw 300, and the spiral groove part 411 moves along the moving groove. The axis of the moving ring 400 extends in a spiral manner, and the connecting groove portion 412 connects the two ends of the spiral groove portion 411. There are multiple balls 500, and the multiple balls 500 can be closely arranged along the transmission groove 410, and the balls 500 that roll into the spiral groove portion 411 cooperate with the threaded groove of the screw 300. The spiral spring bar 600 is arranged in the spiral groove portion 411, and the spiral spring bar 600 is configured to push the balls 500 that roll into the spiral groove portion 411 to be close to the threaded groove of the screw 300. The transmission sleeve 700 is coaxially fixedly connected to the moving ring 400, and the end of the transmission sleeve 700 away from the moving ring 400 is connected to the valve stem of the valve, and the end of the valve stem away from the transmission sleeve 700 is fixedly connected to the valve plate of the valve.

[0021] When closing the valve, the staff controls the motor 200 to start, and drives the screw 300 to rotate in the circumferential direction through the output shaft of the motor 200. Since the ball 500 cooperates with the thread groove of the screw 300 and the spiral groove part 411 of the moving ring 400 at the same time, the torque output by the screw 300 is transmitted to the moving ring 400, so that the moving ring 400 is forced to move downward along its own axis. In this process, the ball 500 circulates and rolls in the transmission groove 410. Since the spiral groove part 411 is provided with a spiral spring bar 600, and the spiral spring bar 600 is configured to push the ball 500 to roll to the spiral groove part 411, the ball 500 is rotated in the transmission groove 410. The ball 500 in the screw 300 is tightly attached to the thread groove of the screw 300, so there is a large positive pressure between the screw 300 and the ball 500. When the screw 300 rotates, the ball 500 will not shake in the thread groove of the screw 300. Similarly, there is a large positive pressure between the spiral spring bar 600 and the ball 500. Therefore, when the screw 300 rotates, the ball 500 will not shake relative to the spiral spring bar 600. Since the spiral spring bar 600 is arranged in the spiral groove part 411, the power of the screw 300 rotation can be accurately transmitted to the moving ring 400 through the ball 500. Compared with the gear reduction mechanism such as the worm gear, when the screw 300 in the present invention is input with power, there will be no relative shaking between the screw 300 and the moving ring 400, so there will be no return error, so that the force when the valve plate of the valve is closed can be accurately controlled to avoid the problem of excessive or insufficient pressure between the valve plate and the valve cavity of the valve. When opening the valve, similarly, the staff controls the motor 200 to start (reverse rotation), and the specific process will not be repeated.

[0022] It can be understood that compared with the traditional transmission form of sliding friction of the screw slider, the transmission form of rolling friction of the ball 500 adopted in the present invention has higher energy conversion efficiency and less wear on the matching position of the screw 300 and the moving ring 400 during the transmission process, thereby improving the service life of the electric linear valve actuator.

[0023] It should also be noted that a limit block 440 is provided on the outer circumferential wall of the movable ring 400, a limit groove is provided on the inner circumferential wall of the housing 100, the limit hole extends along the axis of the movable ring 400, and the limit block 440 is slidably connected in the limit groove.

[0024] In this embodiment, if Figure 7 and Figure 8 As shown, the cross-sectional shape of the spiral groove portion 411 is the same as the cross-sectional shape of the spiral groove of the screw 300, and both are V-shaped.

[0025] The cross-sectional shape of the thread groove of the existing screw 300 is mostly hemispherical, while the cross-sectional shape of the screw 300 in the present invention and the cross-sectional shape of the thread groove of the transmission groove 410 are both V-shaped, thereby increasing the degree of restriction on the freedom of the ball 500, so that when power is transmitted between the screw 300 and the movable ring 400, the ball 500 is not easy to shake relative to the screw 300 and the movable ring 400. As the working time increases, the ball diameter of the ball 500 gradually decreases due to wear. If the thread groove of the screw 300 is a hemispherical groove, there will be a movable gap between the ball 500 and the thread groove of the screw 300, which will cause relative shaking between the screw 300 and the movable ring 400 during power transmission. In the present invention, the cross-sectional shape of the spiral groove part 411 and the cross-sectional shape of the thread groove of the screw 300 are both V-shaped, and a spiral spring bar 600 is provided in the spiral groove part 411. The ball 500 can still maintain a close fit with the thread groove of the screw 300 under the pushing action of the spiral spring bar 600, thereby further extending the service life of the electric linear valve actuator disclosed in the present invention.

[0026] During the valve closing process, as the valve plate gradually moves downward, the flow area of ​​the valve gradually decreases, and the pressure of the fluid on the valve plate continues to increase, which can easily cause the valve plate to deform. To solve this problem, Figure 7 As shown, in this embodiment, an installation cavity 420 is opened inside the movable ring 400, and the installation cavity 420 is connected to the connecting groove part 412. An electromagnetic component 800 is arranged in the installation cavity 420, and the magnetism of the electromagnetic component 800 can be changed. A pressure sensor is arranged in the valve. Specifically, the pressure sensor is arranged on the side of the valve plate facing the fluid. The pressure sensor is electrically connected to the electromagnetic component 800. The ball 500 is magnetic. When the pressure value monitored by the pressure sensor is greater than the preset value, the electromagnetic component 800 is started, and the magnetism of the electromagnetic component 800 changes once every preset time period. When the magnetism of the electromagnetic component 800 is opposite to that of the ball 500, under the magnetic attraction of the electromagnetic component 800, the ball 500 moves from the connecting groove part 412 to the installation cavity 420. When the magnetism of the electromagnetic component 800 is the same as that of the ball 500, under the magnetic action of the electromagnetic component 800, the ball 500 moves from the installation cavity 420 back to the connecting groove part 412.

[0027] When the pressure of the fluid on the valve plate reaches a preset value, the electromagnetic component 800 is started, and the magnetism of the electromagnetic component 800 changes once every preset time period. Specifically, when the magnetism of the electromagnetic component 800 when energized is opposite to the magnetism of the ball 500, under the action of magnetic attraction, part of the ball 500 located in the connecting groove portion 412 moves from the connecting groove portion 412 to the mounting cavity 420. At this time, the ball 500 in the connecting groove portion 412 cannot be tightly arranged in the transmission groove 410 due to the reduction in number. Therefore, at this time, the pre-tightening force of the spiral spring bar 600 on the ball 500 cannot be evenly distributed on all the ball 500 in the transmission groove 410, resulting in a part of the ball 500 in the transmission groove 410 being subjected to excessive pressure, while the other ball 500 in the transmission groove 410 is in a relaxed state. This unbalanced distribution of the pre-tightening force causes a jamming phenomenon (i.e., a momentary pause) to occur during power transmission between the screw 300 and the moving ring 400. At this time, the valve plate no longer continues to move downward. After the preset time period, The current input direction of the electromagnetic component 800 is changed so that the magnetism of the electromagnetic component 800 is changed to be the same as that of the ball 500. At this time, under the action of magnetic repulsion, the ball 500 moves from the installation cavity 420 to the connecting groove portion 412. At this time, the balls 500 in the connecting groove portion 412 are arranged tightly again due to the increase in number. At this time, the jamming phenomenon during power transmission between the screw 300 and the moving ring 400 disappears. Under the driving action of the screw 300, the valve plate of the valve continues to move downward. Since the magnetism of the electromagnetic component 800 changes once at a preset time interval, the valve plate intermittently pauses in the process of moving down to close the valve, which is equivalent to the fluid intermittently pressurizing the valve plate. When the valve plate stops moving down, the valve plate has a certain amount of time to relieve local stress concentration through microstructural adjustment to reduce its deformation degree under the action of force. In addition, by making the valve plate move downward intermittently, the valve plate has the opportunity to release part of the strain energy, reduce the amount of accumulated damage, and thus extend the service life of the valve plate.

[0028] In this embodiment, if Figure 7 As shown, the electromagnetic assembly 800 includes an electromagnet 810 and an elastic member 820. There are two elastic members 820. The two elastic members 820 are spaced apart in the installation cavity 420. One end of the two elastic members 820 away from the installation cavity 420 is fixedly connected to the electromagnet 810. The elastic member 820 is used to prevent the electromagnet 810 from moving along the length direction of the installation cavity 420.

[0029] When the electromagnet 810 is energized, it generates magnetism. When the magnetism generated by the electromagnet 810 is opposite to the magnetism of the ball 500 , the ball 500 moves from the connecting groove portion 412 to the mounting cavity 420 and is adsorbed on the electromagnet 810 under the effect of magnetic attraction.

[0030] When the direction of the current changes when the electromagnet 810 is energized, the magnetism generated by the electromagnet 810 is the same as the magnetism of the ball 500. Under the effect of magnetic repulsion, the electromagnet 810 pushes the ball 500 from the mounting cavity 420 into the connecting groove portion 412, and makes the ball 500 tightly arranged in the connecting groove portion 412.

[0031] It is understandable that the electromagnet 810 is connected by two elastic members 820 so that the electromagnet 810 can move a certain distance along the length direction of the mounting cavity 420 so as to smoothly press the ball 500 in the mounting cavity 420 into the connecting groove portion 412 .

[0032] In this embodiment, if Figure 7 and Fig. 9 As shown, guide blocks 430 are provided at the two connecting positions of the spiral groove portion 411 and the connecting groove portion 412 , and the guide blocks 430 are used to guide the movement of the ball 500 so that the ball 500 can circulate smoothly between the spiral groove portion 411 and the connecting groove portion 412 .

[0033] In this embodiment, if Figure 3 and Figure 7 As shown, the movable ring 400 and the transmission sleeve 700 are threadedly matched to achieve a coaxial fixed connection. Specifically, a thread groove is machined on one end of the movable ring 400, and a threaded portion is opened on the outer peripheral surface of one end of the transmission sleeve 700, and the threaded portion cooperates with the thread groove.

[0034] During installation, the staff only needs to rotate the transmission sleeve 700 to thread the end of the transmission sleeve 700 with the threaded portion into the thread groove of the moving ring 400. Conversely, during disassembly, the staff only needs to rotate the transmission sleeve 700 in the opposite direction.

[0035] In this embodiment, if Figure 3 As shown, one end of the transmission sleeve 700 away from the moving ring 400 is threadedly connected with a connecting end 710, and the end of the transmission sleeve 700 away from the moving ring 400 is connected to the valve stem of the valve through the connecting end 710. Specifically, a threaded portion is provided on the outer periphery of the connecting end 710, and a screw hole is provided in the center of the valve stem. The threaded portion of the connecting end 710 is threadedly connected to the screw hole in the center of the valve stem.

[0036] It can be understood that in the process of the transmission sleeve 700 driving the valve stem to move, the threaded portion of the connecting end 710 and the screw hole in the center of the valve stem are the main stress points, and are therefore more easily crushed and damaged. By connecting the end of the transmission sleeve 700 away from the movable ring 400 to the valve stem of the valve through the connecting end 710, when the connecting end 710 is damaged, only the connecting end 710 needs to be replaced without replacing the entire transmission sleeve 700, thereby saving maintenance costs.

[0037] In this embodiment, if Figure 3 and Figure 4 As shown, a support ring 310 is provided at one end of the screw rod 300 away from the motor 200 , and the outer diameter of the support ring 310 is matched with the inner diameter of the transmission sleeve 700 .

[0038] A support ring 310 is provided to support the end of the screw rod 300 to prevent the end of the screw rod 300 from bending due to a cantilever effect.

[0039] In this embodiment, if Figure 1 As shown, a connecting hole 110 is opened at the lower part of the housing 100, and the diameter of the connecting hole 110 is matched with the diameter of the valve stem of the valve.

[0040] The connecting hole 110 is provided so that the valve stem can pass through the connecting hole 110 and be connected to the connecting end 710 .

[0041] In this embodiment, if Figure 1 As shown, a plurality of threaded holes 120 are provided at equal intervals in the circumferential direction of the connecting hole 110 at the lower portion of the housing 100. The threaded holes 120 correspond one-to-one to the threaded holes 120 on the flange surface of the valve and are connected by bolts, so that the housing 100 and the flange plane of the valve can be fixedly connected together through the threaded holes 120.

[0042] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0043] The above-described embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. An electric linear valve actuator, characterized in that: include: shell; A motor, which is arranged at the upper part of the housing; A screw rod, wherein the screw rod is coaxially connected to an output shaft of the motor; A moving ring is sleeved in the outer shell and can move along its own axis. A transmission groove is provided on the inner circumferential wall of the moving ring. The transmission groove is connected at both ends. The transmission groove includes a spiral groove part and a connecting groove part. The cross-sectional size of the spiral groove part is adapted to the cross-sectional size of the thread groove of the screw. Balls, there are multiple balls, and the multiple balls can be closely arranged along the transmission groove, and the balls rolling into the spiral groove part cooperate with the thread groove of the screw; A spiral spring bar, the spiral spring bar is arranged in the spiral groove part, and the spiral spring bar is configured to push the ball rolling into the spiral groove part to cling to the thread groove of the screw; A transmission sleeve is coaxially and fixedly connected with the moving ring, and one end of the transmission sleeve away from the moving ring is connected with the valve stem of the valve.

2. The electric linear valve actuator according to claim 1, characterized in that: The cross-sectional shape of the spiral groove portion is the same as the cross-sectional shape of the spiral groove of the screw, and both are V-shaped.

3. The electric linear valve actuator according to claim 2, characterized in that: The movable ring is provided with an installation cavity inside, the installation cavity is connected with the connecting groove part, an electromagnetic component is provided in the installation cavity, the magnetism of the electromagnetic component can be changed, a pressure sensor is provided in the valve, and the pressure sensor is electrically connected with the electromagnetic component; The ball is magnetic; The electromagnetic component is configured so that when the pressure value detected by the pressure sensor is greater than a preset value, the electromagnetic component is activated, and the magnetism of the electromagnetic component changes once every preset time period; When the magnetism of the electromagnetic component is opposite to that of the ball, the ball moves from the connecting groove to the installation cavity under the magnetic attraction of the electromagnetic component; When the magnetism of the electromagnetic assembly is the same as that of the ball, the ball moves from the installation cavity back to the communicating groove portion under the magnetic effect of the electromagnetic assembly.

4. The electric linear valve actuator according to claim 3, characterized in that: The electromagnetic assembly includes an electromagnet and an elastic member. There are two elastic members, which are spaced apart in the installation cavity. One end of the two elastic members away from the installation cavity is fixedly connected to the electromagnet. The elastic member is used to prevent the electromagnet from moving along the length direction of the installation cavity.

5. The electric linear valve actuator according to claim 1, characterized in that: Guide blocks are provided at two connection positions of the spiral groove part and the connecting groove part, and the guide blocks are used to guide the movement of the balls.

6. The electric linear valve actuator according to claim 1, characterized in that: The movable ring and the transmission sleeve are matched through threads to achieve coaxial fixed connection.

7. The electric linear valve actuator according to claim 1, characterized in that: The end of the transmission sleeve away from the moving ring is threadedly connected with a connecting end, and the end of the transmission sleeve away from the moving ring is connected to the valve stem of the valve through the connecting end.

8. The electric linear valve actuator according to claim 1, characterized in that: A support ring is arranged at one end of the screw rod away from the motor, and the outer diameter of the support ring is matched with the inner diameter of the transmission sleeve.

9. The electric linear valve actuator according to claim 1, characterized in that: A connecting hole is provided at the lower part of the shell, and the diameter of the connecting hole is matched with the diameter of the valve stem of the valve.

10. The electric linear valve actuator according to claim 9, characterized in that: A plurality of threaded holes are provided at equal intervals in the lower part of the shell and circumferentially of the connecting hole. The threaded holes correspond to the threaded holes on the flange surface of the valve one by one and are connected by bolts.

Images