A linear variable differential transformer LVDT bracket

Abstract

The present invention discloses a linear variable differential transformer (LVDT) bracket for reducing the effects of lateral forces on the linear variable differential transformer (LVDT). The present invention comprises an LVDT sleeve, an LVDT feedback rod, a slide, a sliding head, a limit plate, and a limit cover. A protrusion for limiting is provided on the inner wall of the slide away from the LVDT sleeve. A limit groove matching the protrusion is provided on the outer wall of the sliding head near the LVDT sleeve to enable the sliding head to slide within the slide. Several springs are provided on the outer wall of the sliding head at one end away from the LVDT sleeve. The limit cover is sleeved on the outside of the sliding head. A limit portion is provided on the end surface of the sliding head at the end away from the LVDT sleeve. The limit portion comprises a connecting rod, a lower top plate, and an upper top plate. The lower top plate and the upper top plate are respectively fixed to the connecting rod. The limit plate defines a hole having a diameter smaller than that of the lower top plate and the upper top plate, and larger than that of the connecting rod. The limit plate is mounted between the lower top plate and the upper top plate and fixed within the limit cover.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of mechanical technology, and in particular to a linear variable differential transformer (LVDT) bracket. Background Art

[0002] A linear variable differential transformer (LVDT) is a linear displacement sensor that is generally composed of a sleeve and an iron core. There is a coil inside the sleeve. The movement of the iron core inside the sleeve causes a change in electromotive force, thereby accurately detecting the displacement.

[0003] LVDT sensors are widely used in thermal power plants to accurately detect and control the opening of the turbine's throttle valve. Generally, the LVDT sleeve is fixed to the turbine body, and one end of the iron core is connected to the throttle valve through a connecting rod mechanism. When the throttle valve is opened or closed or other changes occur, the iron core will move within a fixed stroke. The movement of the iron core will cause the electromotive force in the sleeve to change, thereby achieving accurate measurement of linear displacement.

[0004] However, in the existing technology, the steam turbine will generate vibration when working, and the vibration will be transmitted to the LVDT core and sleeve. When the core is moving, the vibration of the steam turbine will cause the core to generate a certain lateral force. After a long time, the core is extremely prone to bending and deformation, causing the core to shift, thereby damaging the sleeve and the internal coil, causing the LVDT sensor to fail, and thus causing the steam turbine to malfunction. Summary of the Invention

[0005] An embodiment of the present application provides a linear variable differential transformer (LVDT) bracket for reducing the influence of lateral force on the linear variable differential transformer (LVDT).

[0006] The linear variable differential transformer (LVDT) bracket provided in the embodiment of the present application includes:

[0007] LVDT sleeve, LVDT feedback rod, slide, sliding head, limit plate and limit cover;

[0008] The LVDT feedback rod is connected to the LVDT sleeve; the slide is sleeved on the LVDT feedback rod, and a through hole matching the outer diameter of the feedback rod is provided on the slide close to the LVDT sleeve, and a protrusion for limiting is provided on the inner wall of the slide away from the LVDT sleeve; the sliding head is provided with an axial fixing hole, and the sliding head is connected to the LVDT feedback rod through the fixing hole, and a limiting groove matching the protrusion is provided on the outer wall of the sliding head close to the LVDT sleeve to enable the sliding head to slide in the slide ; Several springs are provided on the outer wall of the end of the sliding head away from the LVDT sleeve, the limit cover is sleeved on the outside of the sliding head, and a limit part is provided on the end surface of the end of the sliding head away from the LVDT sleeve, the limit part includes a connecting rod, a lower top plate and an upper top plate, the lower top plate and the upper top plate are respectively fixed on the connecting rod, the limit plate is provided with a hole with a diameter smaller than that of the lower top plate and the upper top plate, and a diameter larger than that of the connecting rod, the limit plate is installed between the lower top plate and the upper top plate, and the limit plate is fixed in the limit cover.

[0009] Optionally, the number of the springs is four, and the springs are respectively installed on the upper side, the lower side, the left side and the right side of the outer wall of the end of the sliding head away from the LVDT sleeve.

[0010] Optionally, a floating mark is provided on the sliding head, and a scale mark is provided on the outer wall of the sliding cylinder. The floating mark is used to cooperate with the scale mark to indicate the displacement change of the LVDT feedback rod.

[0011] Optionally, a slideway is provided on the outer wall of the slide cylinder, the floating mark passes through the slideway, and the indicating head of the floating mark protrudes from the outer wall of the slide cylinder.

[0012] Optionally, a fixed base is further included, wherein the fixed base is provided with a hole matching the LVDT sleeve, and the fixed base is sleeved on the outside of the LVDT sleeve to fix the LVDT sleeve.

[0013] Optionally, a threaded hole is provided at the bottom of the fixed base.

[0014] Optionally, the inner wall of the slide cylinder has four protrusions, and the outer wall of the sliding head has four limiting grooves matching the protrusions.

[0015] Optionally, the protrusions are evenly distributed on the inner wall of the slide cylinder.

[0016] Optionally, the distance between the two symmetrical protrusions is equal to the diameter of the through hole of the slide cylinder close to the LVDT sleeve.

[0017] Optionally, it is characterized in that the end of the LVDT feedback rod close to the sliding head is provided with a thread, the inner wall of the fixing hole is provided with a thread, and the LVDT feedback rod is connected to the sliding head through the thread.

[0018] It can be seen from the above technical solutions that the embodiments of the present application have the following beneficial effects:

[0019] In the linear variable differential transformer LVDT bracket provided in the embodiment of the present application, a sliding head can slide in a sliding cylinder. The sliding head is fixed to one end of the LVDT feedback rod. A spring is provided at the head of the sliding head. The sliding head works in conjunction with a limit cover. However, when subjected to vibration, the spring can filter the vibration to a certain extent and offset the offset force caused by the vibration. The offset force will not directly act on the LVDT feedback rod, thereby reducing the bending deformation of the LVDT feedback rod due to the influence of the offset force, thereby reducing the occurrence of failure of the LVDT sensor due to the bending of the LVDT feedback rod. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A schematic diagram of the structure of the linear variable differential transformer LVDT bracket in this application;

[0021] Figure 2 Schematic diagram of the exploded structure of the linear variable differential transformer LVDT bracket in this application;

[0022] Figure 3 It is a front view of the sliding head in this application;

[0023] Figure 4 A bottom view of the sliding head in this application;

[0024] Figure 5 A top view of the slide in this application;

[0025] Figure 6 A schematic diagram of the structure of the limiting cover in this application;

[0026] Figure 7 A structural diagram of a fixed base in this application;

[0027] Figure 8 This is another structural diagram of the fixed base in this application. DETAILED DESCRIPTION

[0028] An embodiment of the present application provides a linear variable differential transformer (LVDT) bracket for reducing the influence of lateral force on the linear variable differential transformer.

[0029] In this application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inside", "outside", "middle", "vertical", "horizontal", "lateral", "longitudinal", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only used to illustrate the relative position relationship between the various components or components, and do not particularly limit the specific installation orientation of the various components or components.

[0030] Furthermore, some of the above terms may be used to express other meanings besides indicating a position or location. For example, the term "on" may also be used to indicate a dependency or connection in certain circumstances. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0031] Furthermore, the terms "installed," "disposed," "provided with," "connected," and "connected" should be interpreted broadly. For example, they can refer to fixed connections, removable connections, or integral structures; mechanical connections or electrical connections; direct connections, indirect connections through an intermediary, or internal communication between two devices, elements, or components. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0032] In addition, the structures, proportions, sizes, etc. drawn in the drawings in this application are only used to match the contents disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the conditions under which this application can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the efficacy and purpose that can be achieved by this application.

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

[0034] A linear variable differential transformer (LVDT) is a linear displacement sensor that is generally composed of a sleeve and an iron core. There is a coil inside the sleeve. The movement of the iron core inside the sleeve causes a change in electromotive force, thereby accurately detecting the displacement.

[0035] LVDT sensors are widely used in thermal power plants to accurately detect and control the opening of the turbine's throttle valve. Generally, the LVDT sleeve is fixed to the turbine body, and one end of the iron core is connected to the throttle valve through a connecting rod mechanism. When the throttle valve is opened or closed or other changes occur, the iron core will move within a fixed stroke. The movement of the iron core will cause the electromotive force in the sleeve to change, thereby achieving accurate measurement of linear displacement.

[0036] However, in the existing technology, the steam turbine will generate vibration when working, and the vibration will be transmitted to the LVDT core and sleeve. When the core is moving, the vibration of the steam turbine will cause the core to generate a certain lateral force. After a long time, the core is extremely prone to bending and deformation, causing the core to shift, thereby damaging the sleeve and the internal coil, causing the LVDT sensor to fail, and thus causing the steam turbine to malfunction.

[0037] Based on this, see Figures 1 to 6 The linear variable differential transformer LVDT bracket provided in the embodiment of the present application includes:

[0038] LVDT sleeve 1, LVDT feedback rod 2, slide 3, sliding head 4, limit plate 5 and limit cover 6;

[0039] The LVDT feedback rod 2 is connected to the LVDT sleeve 1; the slide 3 is sleeved on the LVDT feedback rod 2. The slide 3 is provided with a through hole matching the outer diameter of the feedback rod on the side close to the LVDT sleeve 1, and a raised portion 31 for limiting is provided on the inner wall of the slide 3 away from the LVDT sleeve 1.

[0040] The sliding head 4 is provided with an axial fixing hole 41, through which the sliding head 4 is connected to the LVDT feedback rod 2. The outer wall of the sliding head 4, close to the LVDT sleeve 1, is provided with a limiting groove 42 that matches the protrusion 31 to enable the sliding head 4 to slide within the slide cylinder 3.

[0041] Several springs 43 are provided on the outer wall of the end of the sliding head 4 away from the LVDT sleeve 1, and a limit cover 6 is sleeved on the outside of the sliding head 4. A limit part 44 is provided on the end surface of the sliding head 4 away from the LVDT sleeve 1. The limit part includes a connecting rod 441, a lower top plate 442 and an upper top plate 443. The lower top plate 442 and the upper top plate 443 are respectively fixed on the connecting rod 441. The limit plate 5 is provided with a hole with a diameter smaller than the lower top plate 442 and the upper top plate 443, and a diameter larger than the connecting rod 441. The limit plate 5 is installed between the lower top plate 442 and the upper top plate 443, and the limit plate 5 is fixed in the limit cover 6.

[0042] In practical applications, the LVDT sleeve 1 is generally fixed to the body of the steam turbine, and the limit cover 6 is connected to the turbine regulating valve through a connecting rod mechanism. Changes in the valve opening will drive the movement of the LVDT feedback rod 2, thereby causing changes in the electromotive force within the LVDT sleeve. The valve or the steam turbine body will vibrate during operation, and the vibration is transmitted to the LVDT sensor. The LVDT feedback rod 2 is relatively slender and easily deformed by vibration. In the embodiment of the present application, the slide 3 can be fixed to the LVDT sleeve. The bottom of the slide 3 is provided with a hole with a size similar to that of the LVDT feedback rod 2 to limit the deformation of the LVDT feedback rod 2. The top is connected to the limit groove 42 of the slider 4 through the protrusion 31. The slider 4 is fixed to the end of the LVDT feedback rod 2. When the LVDT feedback rod 2 moves, it drives the slider 4 to slide in the slide 3. At the same time, the slider 4 is restricted by the limit groove 42 and the protrusion 31 and can only move axially, thereby reducing the deflection of the LVDT feedback rod 2.

[0043] A spring 43 is provided at the other end of the slider 4. The end of the slider 4 with the spring 43 is embedded in a limit cover 6. When the limit cover 6 or the LVDT feedback rod 2 vibrates, the vibration does not directly act on the LVDT feedback rod 2. Instead, it is transmitted to the spring 43. The spring 43 filters out some of the vibration, reducing its impact on the LVDT feedback rod 2. The limit cover 6 prevents the LVDT feedback rod 2 from excessively deflecting during vibration. A limit plate 5 is provided within the limit cover 6. During installation, the limit plate 5 is installed between the lower top plate 442 and the upper top plate 443. A certain gap is provided between the lower top plate 442 and the upper top plate 443 to allow limited axial movement of the slider 4. Vibration may cause axial movement of the LVDT feedback rod 2. High-frequency vibration can cause significant damage to the LVDT feedback rod 2 and result in abnormal measured values. Therefore, the limit portion 44 and the limit plate 5 cooperate to offset the axial movement caused by vibration. The upper and lower limit plates can drive the LVDT feedback rod 2 during normal operation.

[0044] Optional, see Figures 1 to 6 There are four springs 43 , which are respectively mounted on the upper side, lower side, left side and right side of the outer wall of the end of the sliding head 4 away from the LVDT sleeve 1 .

[0045] In actual applications, the direction of vibration is often very disordered. The springs 43 installed in four directions on the sliding head 4 can fully offset the vibration in each direction and make the force more uniform.

[0046] Optional, see Figures 1 to 6 A floating mark 45 is provided on the sliding head 4, and a scale mark 7 is provided on the outer wall of the slide cylinder 3. The floating mark 45 is used to cooperate with the scale mark 7 to indicate the displacement change of the LVDT feedback rod 2.

[0047] In practical applications, in order to intuitively understand the displacement of the LVDT feedback rod 2, a scale mark 7 can be set on the outer wall of the slide cylinder 3. When the floating mark 45 is at the 0 scale position, the LVDT feedback rod 2 should be at zero phase.

[0048] Specifically, the slide 3 may be provided with a chute, the floating mark 45 passes through the chute, and the indicating head of the floating mark 45 protrudes from the outer wall of the slide 3.

[0049] Optional, see Figure 7 as well as Figure 8 The linear variable differential transformer (LVDT) bracket provided in this embodiment may also be provided with a fixed base 7. The fixed base 7 has a hole that matches the LVDT sleeve 1. The fixed base 7 is mounted on the outside of the LVDT sleeve 1 to secure the LVDT sleeve 1. Furthermore, the bottom of the fixed base 7 may be provided with two or more threaded holes.

[0050] In practical applications, the LVDT sleeve 1 can be fixed to the machine body by the fixing base 7, which can be connected to the machine body with bolts for easy disassembly. In addition, compared with direct welding, it will not cause damage to the LVDT sleeve 1.

[0051] Optionally, a thread is provided on one end of the LVDT feedback rod 2 close to the sliding head 4 , a thread is provided on the inner wall of the fixing hole, and the LVDT feedback rod 2 is connected to the sliding head 4 through the thread.

[0052] The fixing hole is provided with a thread, and when the sliding head 4 is mounted on the LVDT feedback rod 2, the sliding head 4 can be directly rotated and mounted on the LVDT feedback rod 2. The installation is convenient.

[0053] Optionally, the inner wall of the slide cylinder 3 is provided with four protrusions 31 , and the outer wall of the sliding head 4 is provided with four limiting grooves 42 matching the protrusions 31 .

[0054] The four protrusions 31 can be evenly distributed in four directions of the sliding head 4 , which can limit the rotation of the sliding head 4 , and make the force more even, thereby reducing the wear of the sliding head 4 .

[0055] It should be noted that the above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present application. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A linear variable differential transformer (LVDT) bracket, characterized in that: include: LVDT sleeve, LVDT feedback rod, slide, sliding head, limit plate and limit cover; The LVDT feedback rod is connected to the LVDT sleeve; the slide is sleeved on the LVDT feedback rod, and a through hole matching the outer diameter of the feedback rod is provided at one end of the slide close to the LVDT sleeve, and a protrusion for limiting is provided on the inner wall of one end of the slide away from the LVDT sleeve; the sliding head is provided with an axial fixing hole, and the sliding head is connected to the LVDT feedback rod through the fixing hole, and a limiting groove matching the protrusion is provided on the outer wall of the sliding head close to the LVDT sleeve to realize the sliding head Sliding in the cylinder; a plurality of springs are provided on the outer wall of the sliding head away from the LVDT sleeve, the limit cover is sleeved on the outside of the sliding head, and a limit part is provided on the end surface of the sliding head away from the LVDT sleeve, the limit part includes a connecting rod, a lower top plate and an upper top plate, the lower top plate and the upper top plate are respectively fixed on the connecting rod, the limit plate is provided with a hole with a diameter smaller than that of the lower top plate and the upper top plate, and a diameter larger than that of the connecting rod, the limit plate is installed between the lower top plate and the upper top plate, and the limit plate is fixed in the limit cover.

2. The linear variable differential transformer (LVDT) bracket according to claim 1, characterized in that: The number of the springs is four, and the springs are respectively installed on the upper side, the lower side, the left side and the right side of the outer wall of the end of the sliding head away from the LVDT sleeve.

3. The linear variable differential transformer (LVDT) support according to claim 1, wherein: The sliding head is provided with a floating mark, and the outer wall of the sliding cylinder is provided with a scale mark. The floating mark is used to cooperate with the scale mark to indicate the displacement change of the LVDT feedback rod.

4. The linear variable differential transformer (LVDT) support according to claim 3, characterized in that: A slideway is provided on the outer wall of the slide cylinder, the floating mark passes through the slideway, and the indicating head of the floating mark protrudes from the outer wall of the slide cylinder.

5. The linear variable differential transformer (LVDT) support according to claim 1, characterized in that: It also includes a fixed base, which is provided with a hole matching the LVDT sleeve. The fixed base is sleeved on the outside of the LVDT sleeve to fix the LVDT sleeve.

6. The linear variable differential transformer (LVDT) support according to claim 5, characterized in that: The bottom of the fixed base is provided with a threaded hole.

7. The linear variable differential transformer (LVDT) support according to claim 1, characterized in that: The inner wall of the slide cylinder is provided with four protrusions, and the outer wall of the sliding head is provided with four limiting grooves matching the protrusions.

8. The linear variable differential transformer (LVDT) support according to claim 7, characterized in that: The protrusions are evenly distributed on the inner wall of the slide cylinder.

9. The linear variable differential transformer (LVDT) support according to claim 8, characterized in that: The distance between the two symmetrical protrusions is equal to the diameter of the through hole of the slide cylinder close to the LVDT sleeve.

10. A linear variable differential transformer (LVDT) support according to any one of claims 1 to 9, characterized in that: One end of the LVDT feedback rod close to the sliding head is provided with a thread, the inner wall of the fixing hole is provided with a thread, and the LVDT feedback rod is connected to the sliding head through the thread.

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