Straight-stroke electric actuator capable of being adjusted at high precision

Abstract

The invention relates to the technical field of automatic control equipment, in particular to a straight-stroke electric actuator capable of being adjusted at high precision. Comprising an actuator body and a flexible coupler assembled on a push rod of the actuator body, the flexible coupler comprises an upper connecting part and a lower connecting part, and the flexible coupler is used for buffering external loads borne by the actuator body in the working process; a rigid connection butt joint structure generally adopted between a push rod of an existing electric actuator and a valve rod of a valve is replaced by the arranged flexible coupler, the flexible coupler can achieve serial drive between the push rod and the valve rod, and meanwhile buffer isolation can be formed between the push rod and the valve rod; by means of the structure, a resultant force load formed by axial force and radial force borne by the actuator in the working process can be fully buffered, stress distribution can be optimized and dispersed, the bending resistance of the push rod and the valve rod is indirectly improved, and the adjusting stability and precision of the actuator in the long-term operation process are indirectly guaranteed and improved.

Description

Technical Field

[0001] The invention relates to the technical field of automatic control equipment, and specifically proposes a linear electric actuator capable of being adjusted with high precision. Background Art

[0002] A linear-stroke electric actuator refers to a type of actuator that is electrically driven and converts electrical signals into linear displacement mechanical outputs. It is used to drive various types of valves, switch devices, or other mechanical equipment that requires linear motion. In the present invention, it specifically refers to an actuator that is used to drive various types of valves that require linear displacement control, such as stop valves, gate valves, etc., and is used in pipeline systems that require high-precision regulation of valve flow. This type of linear-stroke electric actuator is generally directly installed on the valve, and the actuator's stroke push rod is connected to the valve stem of the valve.

[0003] In the existing linear electric actuator, the travel push rod and the valve stem are basically connected by a rigid connection method such as threaded connection or bolt connection, and the travel push rod and the valve stem constitute a force-bearing whole; when the actuator drives the valve stem to move linearly, the travel push rod and the valve stem are generally subjected to axial force and radial force together, and the axial force is the main force. Without considering the axial force generated by the actuator itself on the push rod, the axial force mainly comes from the force used to overcome the external loads such as valve sealing force and mechanical resistance, and the impact from the inertial force; while the radial force mainly comes from the lateral impact caused by the flow force of the fluid in the pipeline, and also includes the radial component generated by the mechanical resistance. The combined force of the axial force and the radial force will act together on the travel push rod and the valve stem that constitute the rigid connection. When the actuator body is often in a large load or even overloaded working state during long-term operation, it will cause bending deformation or fatigue damage of the travel push rod and the valve stem with a high probability, which will not only affect the service life of the actuator body, but also aggravate the abnormal wear of the internal sealing structure of the valve, and then affect the sealing of the valve and the accuracy of the actuator body for valve regulation and control.

[0004] In the prior art, guide sleeves and guide posts are usually added to enhance the straightness of the stroke push rod and improve its stability and bending resistance during operation. However, in actual work, when a rigid connection is adopted between the stroke push rod and the valve stem, the effect of the above solution is limited and cannot solve the above-mentioned problems to a large extent. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a linear electric actuator that can be adjusted with high precision, which is used to solve the problems mentioned in the above background technology.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme: a linear electric actuator with high-precision adjustment, including an actuator body and a flexible coupling assembled on a push rod of the actuator body, the flexible coupling including:

[0007] The upper connecting part includes a flange sleeve detachably fixed on the push rod and an external cylinder fixed on the bottom end of the flange sleeve. An inner cylinder is arranged inside the external cylinder and is sleeved on the push rod. The inner cylinder is surrounded by a plurality of single-petal cylinder blocks which are independently arranged and mounted on the push rod by key fitting. A lateral buffer layer for buffering radial force is arranged between each single-petal cylinder block and the inner wall of the external cylinder. The external cylinder presses the single-petal cylinder block against the push rod through the lateral buffer layer, and the single-petal cylinder block retains freedom of movement in the radial direction of the external cylinder. A tray is detachably mounted on the bottom end of the push rod, and a buffer gap is left between the tray and the bottom end of the inner cylinder.

[0008] And a lower connecting part, including a transition tube arranged below the inner tube and a docking tube detachably fixed to the bottom end of the transition tube, the tray is located in the transition tube, and a vertical buffer layer for axial force buffering is arranged in the buffer gap in the transition tube, the vertical buffer layer is in contact with the lower end of the outer tube and the upper end of the tray; the bottom ends of multiple single-petal tube blocks pass through the vertical buffer layer and the tray in turn, and are commonly connected with an elastic frame, which is fixed in the transition tube.

[0009] Preferably, the lateral buffer layer is a buffer block embedded and fixed on the inner wall of the external cylinder and made of flexible material, and the single-petal cylinder block is profile-fitted and snap-connected to the corresponding buffer block.

[0010] Preferably, an inner convex ring is concentrically arranged on the inner wall of the transition cylinder; the vertical buffer layer is a buffer spacer made of flexible material and in a circular ring shape, the buffer spacer is sleeved on the bottom of the push rod, and the buffer spacer is covered and fixed on the inner convex ring.

[0011] Preferably, a lower guide pin is vertically fixed to the bottom end of the single-petal cylinder block, and a plurality of lower guide holes corresponding to the plurality of single-petal cylinder blocks are opened on the disk surface of the tray. The lower guide holes are extended holes extending in the radial direction of the tray. The lower guide pin passes through the buffer spacer and the corresponding lower guide hole, and the bottom end of the lower guide pin is fixed on the elastic frame.

[0012] Preferably, an upper guide pin is vertically fixed to the top of the single-petal cylinder block, and a plurality of upper guide holes corresponding to the plurality of single-petal cylinder blocks are opened on the flange of the flange sleeve. The upper guide holes are extended holes extending in the radial direction of the flange sleeve, and the upper guide pin moves along the corresponding upper guide holes.

[0013] Preferably, the elastic frame includes a fixing ring fixed on the inner wall of the transition tube and a plurality of spring sheets fixed on the fixing ring, and the plurality of spring sheets are fixed on the bottom ends of the plurality of lower guide pins in a one-to-one correspondence.

[0014] Preferably, the flange sleeve is a half-assembled structure, and the two half structures of the flange sleeve are both clamped on the push rod by key fitting.

[0015] Preferably, a positioning shaft is coaxially arranged at the bottom end of the push rod, and the buffer spacer is sleeved on the positioning shaft; an annular groove with an annular cutting structure is arranged on the side wall of the buffer spacer, and the inner convex ring is embedded in the annular groove.

[0016] Preferably, the push rod is provided with an internal threaded hole axially from the bottom end, and a screw assembled in the internal threaded hole is fixed at the center of the tray.

[0017] Preferably, a plurality of embedded blocks cooperating with a plurality of buffer blocks are circumferentially distributed on the inner wall of the external cylinder, and the buffer block is provided with an embedded groove for the embedded block to be embedded.

[0018] The above technical scheme has the following advantages or beneficial effects: The present invention provides a straight-stroke electric actuator with high-precision adjustment. The flexible coupling is set to replace the rigidly connected docking structure generally used between the push rod and the valve stem of the existing electric actuator. The flexible coupling can not only realize the series drive between the push rod and the valve stem, but also form a buffer isolation between the push rod and the valve stem. It can fully buffer the combined force load composed of the axial force and radial force exerted on the actuator during operation, and can optimize and disperse the stress distribution, avoid local stress concentration on structures such as the push rod and the valve stem, improve the large load bearing capacity of the actuator, indirectly improve the bending resistance of the push rod and the valve stem, reduce the probability of bending and fatigue damage of the push rod and the valve stem, ensure the straightness of the actuator's straight-stroke displacement, and improve the service life. It also indirectly ensures and improves the stability and accuracy of the actuator's adjustment during long-term operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention and its features, configurations and advantages will become more apparent by reading the detailed description of non-limiting embodiments with reference to the following drawings. The same reference numerals indicate the same parts throughout the drawings, which are not drawn to scale, with emphasis on illustrating the subject matter of the present invention.

[0020] Figure 1 It is a three-dimensional structural schematic diagram of a linear electric actuator that can be adjusted with high precision provided by the present invention.

[0021] Figure 2 It is a front view of a linear electric actuator that can be adjusted with high precision provided by the present invention.

[0022] Figure 3 It is a three-dimensional cross-sectional view of a flexible coupling.

[0023] Figure 4 It is a three-dimensional cross-sectional view of the partial assembly structure of the flexible coupling.

[0024] Figure 5 It is a three-dimensional structural diagram of the putter.

[0025] Figure 6 It is a three-dimensional structural diagram of the flange sleeve.

[0026] Figure 7 It is a three-dimensional cross-sectional view of the assembly of the buffer block and the external cylinder.

[0027] Figure 8 It is a three-dimensional cross-sectional view of the external cylinder.

[0028] Fig. 9 It is a three-dimensional structural diagram of the built-in cylinder.

[0029] Fig.10 It is a three-dimensional structural diagram of a pallet.

[0030] Fig.11 It is a three-dimensional cross-sectional view of the lower connecting part.

[0031] Fig.12 It is a three-dimensional structural diagram of the assembly of the elastic frame and the transition tube.

[0032] In the figure: 1, actuator body; 11, push rod; 111, clamping key; 112, positioning key; 113, positioning shaft; 12, connecting guide frame; 13, guide slider; 2, flexible coupling; 3, upper connecting part; 31, flange sleeve; 311, upper guide hole; 32, external cylinder; 321, embedded block; 33, internal cylinder; 331, single-petal cylinder block; 332, upper guide pin; 333, lower guide pin; 3 4. Buffer block; 341. Embedded groove; 35. Tray; 351. Screw; 352. Lower guide hole; 4. Lower connecting part; 41. Transition tube; 411. Inner convex ring; 412. Square disk end; 42. Butt tube; 421. Square cover; 422. Internal threaded tube; 43. Buffer spacer; 431. Annular groove; 432. Avoidance hole; 44. Elastic frame; 441. Fixed ring; 442. Spring sheet. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0035] like Figure 1 and Figure 2 As shown, a linear electric actuator with high precision adjustment includes an actuator body 1 and a flexible coupling 2 mounted on a push rod 11 of the actuator body 1, and connected to the valve stem of a corresponding controlled valve through the flexible coupling 2. A connecting guide frame 12 is welded to the bottom of the actuator body 1, and the connecting guide frame 12 includes a fixed base that can be fixed to the valve by bolts and two guide columns vertically welded to the fixed base. In order to improve the stability and guidance of the push rod 11, a guide slider 13 is welded to the push rod 11, and the guide slider 13 is slidably installed between the two guide columns of the connecting guide frame 12.

[0036] like Figure 4 and Figure 5 As shown, in order to cooperate with the installation of the flexible coupling 2, two relatively arranged positioning keys 112 are provided on the push rod 11 below the guide slider 13, eight snap-in keys 111 are evenly distributed circumferentially below the two positioning keys 112 on the push rod 11, and a positioning shaft 113 is coaxially provided at the bottom end of the push rod 11; the push rod 11 is integrally processed and formed.

[0037] like Figure 2 , Figure 3 and Figure 6 As shown, the flexible coupling 2 is composed of an upper connecting part 3 connected to the push rod 11 and a lower connecting part 4 connected to the valve stem; the upper connecting part 3 includes a flange sleeve 31, an external cylinder 32, an internal cylinder 33, a buffer block 34 and a tray 35; in order to facilitate assembly, the flange sleeve 31 is a half-assembled structure, the two half structures of the flange sleeve 31 are both matched with the positioning key 112, and are clamped on the push rod 11, the two half structures of the flange sleeve 31 are locked by bolts, and the two half structures and the push rod 11 are fixed by screws.

[0038] like Figure 4 , Figure 7 and Figure 8 As shown, the top of the external cylinder 32 is provided with a flange that docks with the flange of the flange sleeve 31, and the two flanges are locked and fixed by bolts. Eight embedded blocks 321 are evenly distributed on the inner wall of the external cylinder 32. The embedded blocks 321 are integrally formed with the external cylinder 32. The embedded blocks 321 are rectangular block structures. Each embedded block 321 is equipped with a buffer block 34. The buffer block 34 is provided with an embedded groove 341 for the embedded block 321 to be embedded. The buffer block 34 is nested in the embedded block 321 through the embedded groove 341, and the buffer block 34 is tightly attached to the inner wall of the external cylinder 32. In this embodiment, the buffer block 34 is made of rubber material.

[0039] like Figure 3 , Figure 4 and Fig. 9As shown, an inner cylinder 33 sleeved on the push rod 11 is arranged inside the outer cylinder 32, and the inner cylinder 33 is surrounded by eight disconnected and independently arranged single-petal cylinder blocks 331, and the eight single-petal cylinder blocks 331 are assembled on eight buffer blocks 34 one by one, and a profile that can be clamped and fitted with each other is arranged between the single-petal cylinder blocks 331 and the buffer blocks 34, and the single-petal cylinder blocks 331 are clamped on the corresponding buffer blocks 34, and the eight single-petal cylinder blocks 331 are also clamped on eight clamping keys 111 one by one. The outer cylinder 32 presses the single-petal cylinder blocks 331 tightly on the push rod 11 through the buffer blocks 34, and each buffer block 34 independently constitutes a lateral buffer layer located between each single-petal cylinder block 331 and the outer cylinder 32 and used for buffering radial forces.

[0040] like Figure 3 , Figure 4 , Figure 6 and Fig.10 As shown, the push rod 11 is axially provided with an internal threaded hole from the bottom end of the positioning shaft 113, a screw 351 is fixed to the center of the tray 35 by a screw, and the tray 35 is installed in the internal threaded hole by threaded cooperation of the screw 351; and a buffer gap is left between the tray 35 and the bottom end of the built-in cylinder 33. The flange sleeve 31, the external cylinder 32 and the tray 35 are coaxially assembled; in the present embodiment, the upper and lower ends of the single-flap cylinder block 331 are flush with the upper and lower ends of the external cylinder 32; the top and bottom ends of the single-flap cylinder block 331 are respectively vertically fixed with an upper guide pin 332 and a lower guide pin 333, and the upper guide pin 332 and the lower guide pin 333 are integrally formed with the single-flap cylinder block 331; the flange of the flange sleeve 31 is provided with eight upper guide holes 311 which are arranged one-to-one with the eight upper guide pins 332, and the disk surface of the tray 35 is provided with eight lower guide holes 352 which are arranged one-to-one with the eight lower guide pins 333, both of which are extended holes extending in the radial direction of the external cylinder 32, the upper guide pin 332 moves along the corresponding upper guide hole 311, the lower guide pin 333 passes through the corresponding lower guide hole 352, and the lower guide pin 333 moves along the lower guide hole 352. Because an interlayer composed of buffer blocks 34 is provided between each single-valve cylinder block 331 and the external cylinder 32, and the upper and lower ends of the single-valve cylinder block 331 are respectively guided to move correspondingly between the flange sleeve 31 and the tray 35 through the upper guide pin 332 and the lower guide pin 333, each single-valve cylinder block 331 has the freedom to move radially along the external cylinder 32, and each buffer block 34 has a tendency to perform compression buffering due to the movement of the single-valve cylinder block 331.

[0041] like Figure 3 , Figure 4 , Fig.11 and Fig.12As shown, the lower connecting part 4 includes a transition tube 41, a docking tube 42, a buffer spacer 43 and an elastic frame 44; the transition tube 41 is arranged below the external tube 32, and an inner convex ring 411 formed by integral processing is concentrically arranged on the inner wall of the transition tube 41; the buffer spacer 43 is annular and made of rubber material, and an annular groove 431 of annular cutting structure is arranged on the side wall of the buffer spacer 43, the buffer spacer 43 is sleeved on the positioning shaft 113, the inner convex ring 411 is embedded in the annular groove 431, and the buffer spacer 43 covers the inner convex ring 411; the tray 35 is located in the transition tube 41, and the buffer spacer 4 3 is located in the buffer gap to form a vertical buffer layer for buffering axial force. The buffer spacer 43 is clamped up and down to contact between the lower end of the external tube 32 and the upper end of the tray 35. The buffer spacer 43 is provided with a corresponding avoidance hole 432 corresponding to each lower guide pin 333, and the lower guide pin 333 vertically passes through the corresponding avoidance hole 432. The elastic frame 44 includes a fixing ring 441 fixed to the inner wall of the transition tube 41 by screws and eight spring sheets 442 integrally formed on the fixing ring 441. The eight spring sheets 442 are fixed to the bottom ends of the eight lower guide pins 333 by bolts one by one. The docking tube 42 includes a square cover 421 and an internal threaded tube 422 fixed to the bottom end of the square cover 421. The square cover 421 is mounted on the square plate end 412 and fixed by bolts. The internal threaded tube 422 is used for docking the valve stem.

[0042] The flexible coupling 2 provided by the present invention is used for docking installation between the push rod 11 of the actuator body 1 and the valve stem of the valve. The docking installation process can be divided into two steps: pre-installation and formal installation. The specific docking installation process is described below:

[0043] Pre-installation phase

[0044] Located in the upper connecting part 3, eight buffer blocks 34 are first inserted into the inner wall of the outer tube 32 in sequence, and then each single-petal tube block 331 is clamped on the buffer block 34 in sequence to form a No. 1 pre-assembled part.

[0045] Located in the lower connecting portion 4, the buffer spacer 43 is installed in the transition tube 41 to form a second pre-assembled component.

[0046] Formal installation phase

[0047] First, the connecting guide frame 12 is fixed to the installation position of the valve by means of bolts, so that the actuator body 1 is fixed to the valve.

[0048] Then, the flange sleeve 31 is positioned and installed at the position of the positioning key 112 of the push rod 11 and locked. Then, the eight single-petal cylinder blocks 331 in the No. 1 pre-assembled part are vertically aligned with the eight snap-in keys 111 on the push rod 11, and the No. 1 pre-assembled part is pushed upward from the bottom end of the push rod 11, so that the single-petal cylinder block 331 slides upward along the snap-in keys 111 until the flanges of the external cylinder 32 and the flange sleeve 31 are docked and locked with bolts.

[0049] Next, place the No. 2 pre-assembled component directly below the No. 1 pre-assembled component, rotate and adjust it so that the avoidance hole 432 of the buffer pad 43 is aligned with the lower guide pin 333, and then push the No. 2 pre-assembled component upward so that the lower guide pin 333 passes through the avoidance hole 432, and the buffer pad 43 is mounted on the positioning shaft 113. Subsequently, extend the tray 35 toward the transition cylinder 41, and screw the screw 351 into the internal threaded hole of the push rod 11, so that the buffer pad 43 is just clamped between the bottom end of the external cylinder 32 and the upper end of the tray 35.

[0050] Then, the elastic frame 44 is extended into the transition tube 41, and the spring sheets 442 are sequentially locked to the bottom ends of the corresponding lower guide pins 333 by bolts, and the fixing ring 441 is fixed to the inner wall of the transition tube 41 by screws.

[0051] Regarding the installation of the docking tube 42, first, the valve stem is docked and tightened in the internal threaded tube 422, and the square cover 421 is aligned with the square disk end 412 by rotation adjustment. Then, the actuator body 1 is used to control the push rod 11 to move downward so that the square disk end 412 is aligned and pressed into the docking in the square cover 421. Finally, the square cover 421 is locked on the square disk end 412, thereby completing the docking installation between the electric actuator and the valve provided by the present invention.

[0052] In the entire automatic control system, the actuator body 1 is connected to an external controller by wire or wireless means. During actual operation, the controller sends out an instruction electrical signal, and the control circuit inside the actuator body 1 receives the electrical signal and performs analysis and processing. Then, the built-in motor in the actuator body 1 is driven according to the analyzed and processed signal, thereby driving the push rod 11 to move vertically. In the present invention, the push rod 11 indirectly drives the valve stem through the flexible coupling 2 to realize valve control.

[0053] In the prior art, the push rod 11 and the valve stem are generally rigidly connected to form a whole body that is subjected to common force. During the operation of the actuator body 1, the push rod 11 and the valve stem will jointly bear the external load, and the resultant force of the external load can be decomposed into axial force and radial force. In the present invention, the push rod 11 is connected to the valve stem through a flexible coupling 2. As for the upper connecting part 3, the external cylinder 32 is fixed to the push rod 11 as a whole through the flange sleeve 31, and the tray 35 is fixed to the push rod 11 through the screw 351. Therefore, the flange sleeve 31, the external cylinder 32 and the tray 35 form a rigid connection whole with the push rod 11, which is named as the upper whole part; as for the lower connecting part 4, the transition cylinder 41 and the docking cylinder 42 form a rigid connection whole with the valve stem, which is named as the lower whole part; when the actuator body 1 is working, the lower whole part is in upper and lower clamping contact with the lower end of the external cylinder 32 in the upper whole part and the upper end of the tray 35 through the buffer spacer 43, and the axial force will be transmitted to the buffer spacer 43, and the buffer spacer 43 will buffer the axial force through passive compression. On the other hand, the single-petal cylinder block 331 has reserved freedom to move radially along the push rod 11 or the valve stem. Therefore, when subjected to radial force, the elastic frame 44 and the buffer block 34 will jointly buffer the radial force. In addition, multiple single-valve cylinders and buffer blocks 34 are coordinated and distributed around the push rod 11, which can greatly optimize and disperse the stress distribution and avoid local stress concentration; the flexible coupling 2 can not only realize the series drive between the push rod 11 and the valve stem, but also form a buffer isolation between the push rod 11 and the valve stem, and can fully buffer the combined force load composed of the axial force and radial force exerted on the actuator during operation, thereby improving the large load bearing capacity of the actuator, indirectly improving the bending resistance of the push rod 11 and the valve stem, reducing the probability of bending and fatigue damage of the push rod 11 and the valve stem, ensuring the straightness of the actuator's linear displacement, and improving the service life, and also indirectly ensuring and improving the stability and accuracy of the actuator's adjustment during long-term operation.

[0054] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0055] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "connect", "install", and "connect" 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 indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0056] The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can make many possible changes and modifications without departing from the technical solution of the present invention, or modify them into equivalent embodiments with equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of protection of the technical solution of the present invention.

Claims

1. A linear electric actuator capable of high-precision adjustment, characterized in that: The invention comprises an actuator body and a flexible coupling assembled on a push rod of the actuator body, wherein the flexible coupling comprises: The upper connecting part includes a flange sleeve detachably fixed on the push rod and an external cylinder fixed on the bottom end of the flange sleeve, an internal cylinder sleeved on the push rod is arranged inside the external cylinder, the internal cylinder is surrounded by a plurality of single-petal cylinder blocks which are independently arranged and mounted on the push rod by key matching, a lateral buffer layer for radial force buffering is arranged between each single-petal cylinder block and the inner wall of the external cylinder, the external cylinder presses the single-petal cylinder block against the push rod through the lateral buffer layer, and the single-petal cylinder block retains freedom of movement in the radial direction of the external cylinder, a tray is detachably mounted on the bottom end of the push rod, and a buffer gap is left between the tray and the bottom end of the internal cylinder; And a lower connecting part, including a transition tube arranged below the inner tube and a docking tube detachably fixed to the bottom end of the transition tube, the tray is located in the transition tube, and a vertical buffer layer for axial force buffering is arranged in the buffer gap in the transition tube, the vertical buffer layer is in contact with the lower end of the outer tube and the upper end of the tray; the bottom ends of multiple single-petal tube blocks pass through the vertical buffer layer and the tray in turn, and are commonly connected with an elastic frame, which is fixed in the transition tube.

2. A linear electric actuator capable of high-precision adjustment according to claim 1, characterized in that: The lateral buffer layer is a buffer block made of flexible material and embedded and fixed on the inner wall of the external cylinder. The single-petal cylinder block is profile-fitted and clamped on the corresponding buffer block.

3. A linear electric actuator capable of high-precision adjustment according to claim 1, characterized in that: An inner convex ring is concentrically arranged on the inner wall of the transition cylinder; the vertical buffer layer is a buffer spacer made of flexible material and in a circular ring shape, the buffer spacer is sleeved on the bottom of the push rod, and the buffer spacer is covered and fixed on the inner convex ring.

4. A linear electric actuator capable of high-precision adjustment according to claim 3, characterized in that: A lower guide pin is vertically fixed to the bottom end of the single-petal cylinder block, and a plurality of lower guide holes corresponding to the plurality of single-petal cylinder blocks are opened on the disk surface of the tray. The lower guide holes are extended holes extending in the radial direction of the tray. The lower guide pin passes through the buffer spacer and the corresponding lower guide hole, and the bottom end of the lower guide pin is fixed on the elastic frame.

5. A linear electric actuator capable of high-precision adjustment according to claim 4, characterized in that: An upper guide pin is vertically fixed to the top of the single-petal cylinder block, and a plurality of upper guide holes corresponding to the plurality of single-petal cylinder blocks are opened on the flange of the flange sleeve. The upper guide holes are extended holes extending in the radial direction of the flange sleeve, and the upper guide pin moves along the corresponding upper guide holes.

6. A linear electric actuator capable of high-precision adjustment according to claim 4, characterized in that: The elastic frame comprises a fixing ring fixed on the inner wall of the transition tube and a plurality of spring sheets fixed on the fixing ring, and the plurality of spring sheets are fixed on the bottom ends of the plurality of lower guide pins in a one-to-one correspondence.

7. A linear electric actuator capable of high-precision adjustment according to claim 1, characterized in that: The flange sleeve is a half-assembled structure, and the two half structures of the flange sleeve are both clamped on the push rod through key matching.

8. A linear electric actuator capable of high-precision adjustment according to claim 3, characterized in that: A positioning shaft is coaxially arranged at the bottom end of the push rod, and the buffer spacer is sleeved on the positioning shaft; an annular groove with an annular cutting structure is arranged on the side wall of the buffer spacer, and the inner convex ring is embedded in the annular groove.

9. A linear electric actuator capable of high-precision adjustment according to claim 1, characterized in that: The push rod is provided with an internal thread hole along the axial direction from the bottom end, and a screw rod assembled in the internal thread hole is fixed at the center of the tray.

10. A linear electric actuator capable of high-precision adjustment according to claim 2, characterized in that: A plurality of embedded blocks cooperating with a plurality of buffer blocks are circumferentially arranged on the inner wall of the external cylinder, and an embedded groove for embedding the embedded blocks is arranged on the buffer block.

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