CN219933104U - Precise servo control valve for silicon carbide - Google Patents

Abstract

The utility model belongs to the technical field of control valves, and particularly relates to a silicon carbide precise servo control valve. The servo control valve comprises a servo motor, a screw and a control valve, wherein a positioning piece is fixedly arranged on the screw, a fixing piece is arranged outside the screw, the fixing piece is fixedly arranged on the control valve, and a displacement sensor is fixedly arranged on one side, close to the screw, of the fixing piece; the control valve comprises a valve core and a valve seat, and the servo motor, the screw rod and the valve core are coaxially arranged and sequentially connected. According to the utility model, the control valve is effectively connected with the servo motor in a transmission way through the screw structure, the displacement sensor is matched with the control valve to detect the displacement condition of the screw in real time, and the servo controller is combined to realize real-time monitoring and accurate regulation and control of the fluid flow; meanwhile, the built-in pipe of the control valve is prepared from the silicon carbide material with strong corrosion resistance, so that the tolerance of the control valve to fluids such as strong corrosive gases, liquids and the like is effectively enhanced, and the service life is prolonged.

Description

Precise servo control valve for silicon carbide

Technical Field

The utility model belongs to the technical field of control valves, and particularly relates to a silicon carbide precise servo control valve.

Background

The use of valves, particularly control valves, has become an indispensable fluid control device in production and life. With the development of society, the requirements for the production of required accessory devices are increasing as the technological level and the control requirements are increasing. The importance of control valves as important control components in fluid control systems is becoming increasingly prominent. And higher control requirements are provided for the control requirements, safety, flexibility and other characteristics of the control valve.

The vast majority of control valves on the market are difficult to realize precise control on the flow when the opening degree is small, and difficult to control 0-100% on the flow in the whole range, so that in a precise experiment, the precise proportioning of the fluid which needs to generate chemical reaction is difficult, a large amount of raw materials are wasted, the side reaction occupies heavier weight and the like, and a new additional product is generated due to more serious excessive reaction; even when the flow rate of the fluid is regulated, larger fluctuation can be generated, so that the fluid cannot flow stably, and the balance is further influenced; rendering the reaction difficult to occur, the product unusable or adding additional refining costs. And because of the material reason of valve body itself, can't be long-time through taking corrosive gas or liquid, lead to the valve body to produce loss or card to be dund, arouse the inaccurate reaction productivity etc. that influences of flow even more, consequently need change, but frequently change new equipment and also cause very big waste to manpower financial resources even time.

Disclosure of Invention

The utility model aims to solve the problems in the prior art, particularly the problem that the existing valves on the market cannot realize full-range accurate control on fluid flow, the problem that the control valve has low resistance to corrosive fluid and the problem that the control valve oscillates under the condition of small opening, and provides a silicon carbide accurate servo control valve. The control valve is used for controlling the fluid flow more accurately and stably through the linear control system, so that the response speed of the control on the micro flow is improved, the fluid flow is controlled accurately, the stable flow of the fluid can be continuously kept, reactants can react according to the set proportion, the possibility of generating additional products is greatly reduced, the material consumption is reduced due to the accurate control of the flow, the productivity is effectively increased, and the production efficiency is improved; meanwhile, the service life is prolonged and the durability is prolonged by replacing the built-in pipe with a silicon carbide material with strong corrosion resistance.

The technical scheme adopted for solving the technical problems is as follows:

the precise servo control valve comprises a servo motor, a screw and a control valve, wherein a positioning piece is fixedly arranged on the screw, a fixing piece is arranged outside the screw and fixedly arranged on the control valve, a displacement sensor is fixedly arranged on one side, close to the screw, of the fixing piece, and the detection end of the displacement sensor is arranged towards the positioning piece; the control valve comprises a valve core and a valve seat, and the servo motor, the screw rod and the valve core are coaxially arranged and sequentially connected.

Preferably, the connection mode among the servo motor, the screw rod and the valve core comprises common fixed connection such as threaded connection, bolt connection, fixed ring connection, welding and the like, and can also comprise sliding connection such as sleeving connection and the like.

More preferably, the servo motor, the screw rod and the valve core are respectively connected through connecting pieces, so that the coaxial movement of the servo motor, the screw rod and the valve core is realized.

More preferably, the servo motor is connected with the screw rod through a first connecting piece, the first connecting piece is respectively connected with the shaft rod of the servo motor and the screw rod, and the servo motor is fixedly connected or slidingly connected with the screw rod; the preferable fixed connection can be that the servo motor and the screw rod jointly move through a threaded connection, a bolt connection, a fixed ring connection, welding and the like; the sliding connection is that the screw rod can still realize the relative movement of up-and-down displacement on the premise that the servo motor is fixed;

more preferably, the sliding connection may be that the first connecting piece is sleeved on the screw rod, so that the screw rod can realize the relative movement of up-and-down displacement under the condition that the servo motor is fixed;

more preferably, the up-and-down relative movement of the screw can be achieved by the following scheme: the first connecting piece is connected to the shaft lever of the servo motor, and can drive the first connecting piece to rotate when the shaft lever of the servo motor rotates, and a clamping structure relationship exists between the first connecting piece and the screw rod, so that the screw rod can be driven to rotate when the first connecting piece rotates, and the screw rod can realize relative movement of up-and-down displacement relative to the first connecting piece due to the sleeving relationship of the screw rod and the first connecting piece;

for example, the connection part of the screw rod and the first connecting piece is square, the part of the first connecting piece sleeved on the screw rod is also matched square, and a clamping structure relationship is formed between the first connecting piece and the square part of the screw rod, so that the first connecting piece can drive the screw rod to rotate due to the sleeved relationship and the clamping structure; meanwhile, the screw rod is enabled to generate up-and-down displacement due to the threaded connection relation between the screw rod and the control valve, and the screw rod and the first connecting piece can relatively slide due to the sleeving relation between the screw rod and the first connecting piece, so that the relative movement between the screw rod and the first connecting piece is realized.

More preferably, the screw rod is connected with the valve core through the second connecting piece, so that the screw rod can drive the valve core to realize coaxial up-and-down displacement, and the valve is opened and closed, the flow on-off and the flow fine adjustment performance are realized with a matched valve seat, and the effects of opening the control valve and accurately adjusting the flow are realized. More preferably, the connection mode of the screw rod and the valve core is fixed connection, and even more preferably common fixed connection such as threaded connection, bolt connection, fixed ring connection, welding and the like, so that the screw rod generates up-and-down displacement and the up-and-down displacement of the valve core is necessarily caused, and the displacement is matched.

Preferably, the positioning piece is fixedly arranged on the screw, the fixed arrangement means that the screw and the positioning piece can be regarded as a whole when the position relationship is judged, and more preferably, the positioning piece can be arranged on the screw in a detachable or non-detachable connection mode such as welding, threaded connection, buckling connection, sleeving connection and the like, so that the positioning piece generates the same movement displacement along with the screw and is in the same movement state.

Preferably, the fixing arrangement in the utility model can be a detachable or non-detachable connection mode such as welding, threaded connection, snap connection, sleeving connection and the like.

Preferably, the fixing piece comprises a side piece, the side piece is fixedly arranged on the control valve, and the displacement sensor is arranged on one side of the side piece, close to the screw rod, and is used for enabling the displacement sensor to be fixedly arranged and not move along with the screw rod and the like; more preferably, the side piece is a common form part such as a side plate or a side rod and the like, and the form part can be fixedly provided with a displacement sensor.

More preferably, the fixing piece can further comprise a bottom piece, wherein the bottom piece is fixedly arranged on the control valve and fixedly connected with the side piece, so that the stability of the side piece is further enhanced; more preferably, the bottom piece is sleeved on the screw rod, and the contact part of the bottom piece and the screw rod is provided with threads matched with the screw rod, so that the screw rod and the fixing piece can relatively displace through a threaded connection relation, and the screw rod can axially move relative to the fixing piece.

Preferably, the displacement sensor is a contact type displacement sensor or a non-contact type displacement sensor; more preferably, the detection end of the distance measuring rod of the contact displacement sensor is connected with the positioning piece and moves along with the movement of the positioning piece, so that the displacement signal of the positioning piece is measured, and the accurate flow control of the control valve is realized; more preferably, the non-contact type displacement sensor is provided with a detection end facing the positioning piece, and can realize signal transmission with the positioning piece.

Preferably, the side wall of the valve seat is provided with a liquid inlet, the bottom of the valve seat is provided with a liquid outlet, and the liquid inlet and the liquid outlet are communicated in the inner space of the valve seat, so that fluid can enter the valve seat through the liquid inlet and flow out through the liquid outlet, the valve seat is matched with the valve core, the valve core is arranged in the valve seat, and the axial movement of the valve core can realize the regulation and control of the size of the liquid inlet and the on-off of the liquid inlet and the liquid outlet;

more preferably, the liquid inlet of the valve seat is at least provided with an upper wide and lower narrow structure, more preferably the upper wide and lower narrow structure is at least one of an inverted trapezoid structure and an inverted triangle structure, and even more preferably the liquid inlet is an inverted triangle structure. When the liquid inlet is provided with a structure with a wide upper part and a narrow lower part, particularly an inverted triangle structure, the flow of the fluid can be accurately regulated and controlled from 0% -100%, so that the fluid can flow stably and slightly at the beginning, and the subsequent reaction environment is prevented from being greatly influenced, impacted and oscillated, and the stability of the subsequent reaction environment is further maintained; more preferably, the liquid inlet can be a combination of a plurality of structures with wide upper part and narrow lower part, or a combination of other conventional structures and one structure with wide upper part and narrow lower part (the structure with wide upper part and narrow lower part is positioned at the lower part), so that various flow regulation and control requirements are expanded and matched; however, it should be noted that the present utility model is only a preferred solution, and in fact, the liquid inlet may be of a conventional structure, such as a circular shape, a rectangular shape, etc., and may be selected according to practical situations, where there is no requirement for stability, full-scale flow regulation, etc. of the fluid flow.

More preferably, the valve seats can be multiple, and the valve core comprises an upper part, a connecting part and a lower part, wherein the upper part of the valve core is coaxially connected with the screw rod, and the upper part of the valve core is driven by the screw rod to realize axial movement; the lower part of case is provided with a plurality of to cooperate the setting with the disk seat respectively, and the lower part passes through connecting portion to the upper portion of case, thereby when driving case upper portion axial motion through the screw rod, also can drive a plurality of lower parts and realize axial motion, and through the cooperation setting with the disk seat, realize the effect of a plurality of control valves, thereby realize the flow control of a plurality of pipelines simultaneously, do benefit to the batch control of fluid flow when industrialization batch production operation, simple and convenient operation flow, high-efficient production operation.

Preferably, the valve body and the valve seat are made of a silicon carbide material having strong corrosion resistance, and more preferably, the control valve is made of a silicon carbide material. The valve core and the valve seat are prepared from the silicon carbide material with strong corrosion resistance, so that the silicon carbide precise servo control valve is suitable for controlling and precisely regulating the flow of highly corrosive fluid, and reduces loss, thereby prolonging the precision and the service life of the control valve.

Preferably, the servo motor is also provided with a servo controller in a matched manner and is communicated with the servo controller through a power supply/signal wire, and the displacement sensor is communicated with the servo controller through the power supply/signal wire; therefore, the displacement sensor transmits information into the servo controller, the servo motor is controlled through the servo controller, the information is transmitted in real time, and the real-time monitoring and accurate regulation and control of the fluid flow are completed.

Compared with the prior art, the utility model has the beneficial effects that:

the utility model provides a silicon carbide precise servo control valve, which is characterized in that a screw structure is arranged, a control valve is effectively connected with a servo motor in a transmission way, a displacement sensor is matched with the control valve, the displacement condition of a screw is detected in real time, and meanwhile, corresponding signals are transmitted to a servo controller, the displacement of the screw is further controlled by the servo controller, and the valve core of the control valve is controlled in a transmission way, so that the real-time monitoring and precise regulation and control of the fluid flow are realized; meanwhile, a built-in pipe of the control valve is prepared by adopting a silicon carbide material with strong corrosion resistance, so that the tolerance of the control valve to fluids such as strong corrosive gases, liquids and the like is effectively enhanced, and the service life is prolonged; the silicon carbide precise servo control valve has the following advantages:

(1) The accurate and stable control of the control valve on the fluid flow is effectively improved through the servo motor, the screw structure and the transmission linear control system of the valve core, and the stable flow of the fluid can be continuously maintained; through the accurate control of the fluid flow, reactants can react according to the set proportion, so that the effectiveness of the reaction is greatly ensured, the possibility of generating additional products is reduced, the material consumption is reduced through the accurate control of the flow, the productivity can be effectively increased, and the production efficiency is improved;

(2) The servo motor is matched with the servo controller and is provided with the displacement sensor, so that the response speed of the control valve to micro flow control is effectively improved, and the controllability of the control valve to fluid flow is further improved;

(3) By adopting the silicon carbide material with strong corrosion resistance, the loss of the control valve is reduced, the service life is prolonged, the durability is prolonged, and the cost is reduced; meanwhile, the effectiveness and stability of the reaction are further ensured, and the influence caused by external factors is reduced; therefore, the silicon carbide precise servo control valve has wider market and industrial application prospect.

Drawings

FIG. 1 is a schematic view of the overall structure of the present utility model;

FIG. 2 is a schematic illustration of a valve seat structure of the present utility model;

FIG. 3 is a schematic cross-sectional view of a control valve according to the present utility model;

in the figure: 1. a servo motor; 2. a screw; 3. a control valve; 4. a positioning piece; 5. a displacement sensor; 6. a valve seat.

Detailed Description

The technical solution of the present utility model will be further clearly and completely described below by means of specific examples, and with reference to the accompanying drawings, it should be understood that the described examples of the present utility model are implemented on the premise of the technical solution of the present utility model, and detailed implementation and specific operation procedures are given, but only some examples of the present utility model are not all examples. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

The structure connection operations and the like used in the following examples are conventional methods, and the materials and the like used in the examples are commercially available, unless otherwise specified.

Examples

The utility model provides a silicon carbide precise servo control valve, which is combined with fig. 1 and 3, wherein the servo control valve comprises a servo motor 1, a screw rod 2 and a control valve 3, a positioning piece 4 is fixedly arranged on the screw rod 2, the positioning piece 4 moves or does not move along with the screw rod 2, a fixing piece is arranged outside the screw rod 2 and fixedly arranged on the control valve 3, a displacement sensor 5 is fixedly arranged on one side, close to the screw rod 2, of the fixing piece, and the detection end of the displacement sensor 5 is arranged towards the positioning piece 4; the control valve 3 comprises a valve core and a valve seat 6, and the servo motor 1, the screw rod 2 and the valve core are coaxially arranged and are sequentially connected; wherein, the fixed setting of locating piece 4 on screw rod 2 means that when judging positional relationship, screw rod 2 and locating piece 4 can regard as a whole, set up locating piece 4 on screw rod 2, make it produce the same motion displacement, be in the same motion state along with screw rod 2.

In one embodiment of the present utility model, the fixing means may be a detachable or non-detachable connection means such as welding, screwing, snap connection, socket connection, etc.

In one embodiment of the present utility model, the connection manner between the servo motor 1, the screw rod 2 and the valve core includes common fixed connection such as threaded connection, bolt connection, fixed ring connection, welding, and the like, and may also include sliding connection such as sleeving connection.

In one embodiment of the utility model, the servo motor 1, the screw rod 2 and the valve core are respectively connected through connecting pieces, so that the servo motor 1, the screw rod 2 and the valve core can coaxially move.

In one embodiment of the utility model, the servo motor 1 and the screw rod 2 are connected through a first connecting piece, the first connecting piece is respectively connected with the shaft rod of the servo motor 1 and the screw rod 2, and the connection mode between the servo motor 1 and the screw rod 2 is fixed connection or sliding connection; the preferable fixed connection can be that the servo motor 1 and the screw rod 2 move together by means of threaded connection, bolt connection, fixed ring connection, welding and the like; at this time, the screw 2 is displaced up and down, and the servo motor 1 is synchronously displaced.

In one embodiment of the utility model, the first connecting piece is fixedly connected with the shaft lever of the servo motor 1 and is in sliding connection with the screw rod 2; the sliding connection is that the screw rod 2 can still realize the relative movement of up-and-down displacement on the premise that the servo motor 1 is fixed; more preferably, the sliding connection may be that the first connecting piece is sleeved on the screw rod 2, so that the screw rod 2 can realize the relative movement of up and down displacement under the condition that the servo motor 1 is fixed.

In one embodiment of the present utility model, the up-and-down relative movement of the screw 2 can be achieved by: the first connecting piece is connected to the shaft lever of the servo motor 1, and can drive the first connecting piece to rotate when the shaft lever of the servo motor 1 rotates, and a clamping structure relationship exists between the first connecting piece and the screw rod 2, so that the screw rod 2 can be driven to rotate when the first connecting piece rotates, and the screw rod 2 and the first connecting piece are in sleeved connection so that the screw rod 2 can realize relative movement of up-and-down displacement relative to the first connecting piece;

for example, the connection part of the screw rod 2 and the first connecting piece is square, the part of the first connecting piece sleeved on the screw rod 2 is also matched square, and a clamping structure relationship is formed between the first connecting piece and the square part of the screw rod 2, so that the first connecting piece can drive the screw rod 2 to rotate due to the sleeved relationship and the clamping structure; meanwhile, the screw rod 2 is in up-and-down displacement due to the threaded connection relation with the control valve 3, and the screw rod 2 and the first connecting piece can relatively slide due to the sleeving relation, so that the relative movement with the first connecting piece is realized.

In one embodiment of the utility model, one end of the screw rod 2 far away from the servo motor 1 is connected with the valve core through the second connecting piece, so that the screw rod 2 can drive the valve core to realize coaxial up-and-down displacement, and realize the opening and closing of the valve, the flow on-off and the flow fine adjustment performance with the matched valve seat 6, thereby realizing the effects of opening the control valve 3 and accurate flow adjustment, and improving the response speed for controlling the tiny flow of the fluid under the action of the displacement sensor 5. More preferably, the connection mode of the screw rod 2 and the valve core is fixed connection, and even more preferably common fixed connection such as threaded connection, bolt connection, fixed ring connection, welding and the like, so that the screw rod 2 generates up-and-down displacement and the up-and-down displacement of the valve core is necessarily caused, and the displacement amounts are matched.

In one embodiment of the present utility model, the fixing member includes a side member, and the side member is fixedly disposed on the control valve 3, the displacement sensor 5 is disposed on a side of the side member near the screw 2, and the displacement sensor 5 is disposed above the positioning member 4, so that the displacement sensor 5 is fixedly disposed and does not move along with the screw 2; more preferably, the side pieces are common components such as side plates or side rods, etc., which can be fixedly provided with the displacement sensor 5.

In one embodiment of the utility model, the fixing piece further comprises a bottom piece, wherein the bottom piece is fixedly arranged on the control valve 3 and fixedly connected with the side piece, so that the stability of the side piece is further enhanced; more preferably, the bottom part is internally provided with threads and is matched with the threads on the screw rod 2, so that the screw rod 2 and the fixing part can relatively displace through a threaded connection relationship, and the screw rod 2 can axially move relative to the fixing part.

In one embodiment of the present utility model, the displacement sensor 5 is a contact displacement sensor, and the contact displacement sensor further includes a ranging rod, where a detection end of the ranging rod is connected to the positioning member 4, and moves along with the movement of the positioning member 4, so as to measure a displacement signal of the positioning member 4, thereby realizing accurate flow control of the control valve 3.

In one embodiment of the present utility model, the displacement sensor 5 is a non-contact displacement sensor, and a detection end of the non-contact displacement sensor is disposed towards the positioning member 4 and is capable of realizing signal transmission with the positioning member 4.

In one embodiment of the present utility model, the side wall of the valve seat 6 is provided with a liquid inlet, the bottom of the valve seat 6 is provided with a liquid outlet, and the liquid inlet is communicated with the liquid outlet in the internal space of the valve seat 6, so that fluid can enter the valve seat 6 through the liquid inlet and flow out through the liquid outlet, the valve seat 6 is arranged in cooperation with a valve core, the valve core is arranged in the valve seat 6, and the axial movement of the valve core can realize the regulation and control of the size of the liquid inlet and the on-off of the liquid inlet and the liquid outlet.

In an embodiment of the present utility model, referring to fig. 2 and fig. 3, the liquid inlet of the valve seat 6 is at least provided with an upper wide and lower narrow structure, and more preferably, the upper wide and lower narrow structure is at least one of an inverted trapezoid structure and an inverted triangle structure.

In one embodiment of the utility model, the liquid inlet of the valve seat 6 is of an inverted triangle structure, so that the flow of the fluid can be accurately regulated and controlled from 0% -100%, and the fluid can flow stably and slightly at the beginning, so that the subsequent reaction environment is prevented from being greatly influenced, impacted and oscillated, and the stability of the subsequent reaction environment is further maintained.

In one embodiment of the present utility model, more preferably, the liquid inlet may be a combination of multiple structures with wide upper and narrow lower, or a combination of other conventional structures and one structure with wide upper and narrow lower (the structure with wide upper and narrow lower is located at the lower part), so as to expand and match multiple flow regulation requirements; for example, the liquid inlets are arranged in a left-right combination way of two inverted triangle structures, and the top angles of the bottommost parts of the two inverted triangles have displacement differences in the longitudinal direction; or the liquid inlet is arranged in a vertical combination way of a coaxial rectangular structure and an inverted triangle structure.

In one embodiment of the present utility model, the liquid inlet may be configured in a conventional structure, such as a circular shape, a rectangular shape, etc., and may be selected according to practical situations, without requirements for smoothness, full-scale flow regulation, etc. of the fluid flow.

In one embodiment of the present utility model, the valve seat 6 may be multiple, where the valve core includes an upper portion, a connecting portion, and a lower portion, the upper portion of the valve core is coaxially connected with the screw 2, and the upper portion of the valve core is driven by the screw 2 to implement axial movement; the lower part of case is provided with a plurality of to cooperate with disk seat 6 respectively and set up, and the lower part passes through connecting portion to the upper portion of case, thereby when driving case upper portion axial motion through screw rod 2, also can drive a plurality of lower parts and realize axial motion, and through the cooperation setting with disk seat 6, realize the effect of a plurality of control valves 3, thereby realize the simultaneous flow control of a plurality of pipelines, do benefit to the batch control of fluid flow when industrialization batch production operation, simple and convenient operation flow, high-efficient production operation.

In one embodiment of the present utility model, the valve body and the valve seat 6 are made of a silicon carbide material having strong corrosion resistance, and more preferably, the control valve 3 is made of a silicon carbide material. The valve core and the valve seat 6 are prepared from the silicon carbide material with strong corrosion resistance, so that the silicon carbide precise servo control valve is suitable for controlling and precisely regulating the flow of highly corrosive fluid, and reduces loss, thereby prolonging the precision and the service life of the control valve 3.

In one embodiment of the present utility model, the servo motor 1 is further provided with a servo controller in a matching manner, and is electrically connected and signal-connected and transmitted with the servo controller through a power/signal line, etc., and the displacement sensor 5 is communicated with the servo controller through the power/signal line; therefore, the displacement sensor 5 transmits information into the servo controller, the servo motor 1 is controlled through the servo controller, the information is transmitted in real time, and the real-time monitoring and accurate regulation and control of the fluid flow are completed.

The working principle of the silicon carbide precise servo control valve provided by the utility model is as follows: through the linear transmission system of the servo motor 1, the screw rod 2, the control valve 3 and corresponding connecting pieces, the servo motor 1 rotates and drives the screw rod 2 to rotate at the same time, the screw rod 2 generates up-and-down displacement due to the threaded structure of the screw rod 2, and the valve core of the control valve 3 is driven to generate synchronous up-and-down displacement, so that the servo motor 1 can control the up-and-down displacement effect of the valve 3 core; meanwhile, the screw rod 2 is also provided with a positioning piece 4, so that the displacement of the valve core is equal to the displacement of the positioning piece 4 through displacement transmission, displacement information is transmitted to a servo controller through a displacement sensor 5 which is matched with the positioning piece, the movement of the servo motor 1 is further controlled under the actions of signal processing and the like of the servo controller, and the displacement of the valve 3 core is further controlled; thereby realizing the accurate control of the control valve 3 on the tiny flow of the fluid, controlling the full range of the flow by 0-100%, and improving the response speed; meanwhile, under the action of the silicon carbide material with strong corrosion resistance, the service life of the control valve 3 is prolonged, and the industrial production cost is reduced.

The above-described embodiments are only preferred embodiments of the present utility model, and are not intended to limit the utility model in any way, but other variations and modifications are possible without exceeding the technical solutions described in the claims.

Claims (10)

1. The silicon carbide precise servo control valve is characterized by comprising a servo motor (1), a screw rod (2) and a control valve (3), wherein a positioning piece (4) is fixedly arranged on the screw rod (2), a fixing piece is arranged outside the screw rod (2) and fixedly arranged on the control valve (3), a displacement sensor (5) is fixedly arranged on one side, close to the screw rod (2), of the fixing piece, and the detection end of the displacement sensor (5) is arranged towards the positioning piece (4); the control valve (3) comprises a valve core and a valve seat (6), and the servo motor (1), the screw (2) and the valve core are coaxially arranged and connected in sequence.

2. The silicon carbide precise servo control valve according to claim 1, wherein the servo motor (1), the screw (2) and the valve core are respectively connected through connecting pieces.

3. The silicon carbide precision servo control valve according to claim 1, characterized in that the fixing member comprises a side member, the side member is fixedly arranged on the control valve (3), and the displacement sensor (5) is arranged on one side of the side member, which is close to the screw (2).

4. A silicon carbide precision servo control valve according to claim 3, characterised in that the fixing member further comprises a base member fixedly arranged on the control valve (3) and fixedly connected to the side member.

5. The silicon carbide precision servo control valve according to claim 1, characterized in that the displacement sensor (5) is a contact displacement sensor or a non-contact displacement sensor.

6. The silicon carbide precision servo control valve according to claim 5, wherein the detection end of the distance measuring rod of the contact displacement sensor is connected with the positioning piece (4).

7. The silicon carbide precise servo control valve according to claim 1, wherein a liquid inlet is formed in the side wall of the valve seat (6), a liquid outlet is formed in the bottom of the valve seat (6), and the liquid inlet and the liquid outlet are communicated in the inner space of the valve seat (6).

8. The silicon carbide precision servo control valve according to claim 7, wherein the liquid inlet of the valve seat (6) is provided with at least one structure with a wider upper part and a narrower lower part.

9. A silicon carbide precision servo control valve according to claim 1, characterized in that the valve core and valve seat (6) are made of silicon carbide material with strong corrosion resistance.

10. A silicon carbide precision servo control valve according to claim 1, characterized in that the servo motor (1) is also provided with a servo controller in cooperation.