Linear differential transformer type displacement sensor

Abstract

The utility model discloses a linear differential transformer type displacement sensor, which comprises a shell, a coil tube, a coil and an iron core, two ends of the shell are provided with end covers detachably connected with the shell, the coil tube is positioned in the shell, the coil is wound on the coil tube, the coil is provided with a lead integrally connected with the coil, one end of the iron core is positioned in the coil tube, and the other end of the iron core is connected with the coil tube. The other end penetrates through one end cover of the shell and is in sliding connection with the end cover; a traction force is added to the iron core by adopting a multi-section telescopic sleeve rod or a winding assembly, so that the deflection condition possibly occurring when the gravity center of the iron core is located on the outer side of the shell is avoided; according to the LVDT, the guide assembly and the sliding rail are matched with each other, traditional axial movement of the iron core is transferred to the sliding rail, the requirement for axial movement of the iron core is lowered, and the actual application range of the LVDT is indirectly expanded.

Description

Technical Field

[0001] The utility model relates to the technical field of displacement sensors, in particular to a linear differential transformer type displacement sensor. Background Art

[0002] Linear differential transformer displacement sensor, referred to as LVDT, is a linear displacement sensor that uses the movement of the core to change the coil voltage to achieve displacement detection. It is widely used in complete systems such as ships, aviation, aerospace, and weapons.

[0003] The traditional linear differential transformer displacement sensor has the following problems. First, during the displacement of the core, when the center of gravity of the core is located outside the shell, the core will inevitably tilt. In the prior art, the core is usually prevented from tilting by controlling the movable distance of the core or the length of the shell, which indirectly makes the LVDT have length and displacement distance limitations. Second, the existing LVDT has certain restrictions on its installation space, that is, space for the axial movement of the core needs to be reserved after installation. The above restrictions indirectly narrow the actual scope of use of the LVDT.

[0004] In view of this, there is an urgent need for a linear differential transformer displacement sensor that can solve the above problems. Utility Model Content

[0005] The purpose of the utility model is to provide a linear differential transformer type displacement sensor which solves the above problems.

[0006] In order to achieve the above-mentioned purpose, the utility model adopts the following technical solution: a linear differential transformer displacement sensor, comprising:

[0007] The outer shell comprises an outer shell, a coil tube, a coil and an iron core. Both ends of the outer shell are provided with end covers which are detachably connected thereto. The coil tube is located inside the outer shell. The coil is wound on the coil tube, and the coil is provided with a lead wire which is integrally connected thereto. One end of the iron core is located inside the coil tube, and the other end passes through one of the end covers of the outer shell and is slidably connected thereto.

[0008] Preferably, epoxy resin is poured between the housing and the coil.

[0009] Preferably, a multi-section telescopic sleeve rod is provided on the end cover not in contact with the iron core, one end of the multi-section telescopic sleeve rod is fixedly connected to the end cover, and the other end is fixedly connected to the iron core.

[0010] Preferably, a winding assembly is provided on the end cover that is not in contact with the iron core, and the winding assembly includes a winding box body, a winding shaft, at least one group of spiral springs and a winding wire. The winding box body is fixedly connected to the side wall of the end cover away from the outer shell, and a cylindrical cavity is provided in the winding box body. Both ends of the winding shaft are respectively connected to the side walls of the cylindrical cavity by bearings, and both ends of the spiral spring are respectively fixedly connected to the winding shaft and the curved side walls of the cylindrical cavity. One end of the winding wire is wound around the winding shaft, and the other end passes through the winding box body and the end cover and is fixedly connected to the iron core.

[0011] Preferably, a slide rail fixedly connected to the curved side wall of the shell is provided, a slide groove is provided on the slide rail, and a slider slidably connected to the curved side wall of the shell is provided in the slide groove.

[0012] Preferably, a group of guide components are respectively provided at both ends of the shell, and the guide components include a guide box body, at least one group of guide rollers and guide wires. The guide box body is fixedly connected to the end cover, the guide roller is located in the guide box body, and the bearings at both ends are connected to the inner wall of the guide box body. One end of the guide wire passes through the end cover and is fixedly connected to the iron core, and the other end bypasses the guide roller and passes through the side wall of the slide groove and is fixedly connected to the slider.

[0013] Preferably, the length of the core is shorter than the length of the coil tube.

[0014] Preferably, a guide wire groove matching the guide wire is provided on the curved side wall of the guide roller.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] 1. By using a multi-section telescopic sleeve or a winding assembly, a pulling force is added to the iron core, thereby avoiding the possible deflection of the iron core when the center of gravity is located outside the shell.

[0017] 2. Through the cooperation of the guide assembly and the slide rail, the traditional axial movement of the iron core is transferred to the slide rail, which reduces the requirements for the axial movement of the iron core and indirectly expands the practical application range of LVDT. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of a linear differential transformer displacement sensor;

[0019] Figure 2 It is a schematic diagram of the cross-sectional structure inside the shell of the utility model;

[0020] Figure 3 This is a schematic diagram of the cross-sectional structure of the interior of the housing in the second embodiment of the present utility model;

[0021] Figure 4 This is a schematic diagram of the cross-sectional structure of the interior of the housing in the third embodiment of the present utility model;

[0022] Figure 5 Schematic diagram of the cross-sectional structure of the scroll spring in the third embodiment of the present utility model;

[0023] Figure 6 This is a schematic diagram of the position structure of the slide rail and the guide assembly in the fourth embodiment of the utility model;

[0024] Figure 7 It is a schematic diagram of the cross-sectional structure inside the shell in the fourth embodiment of the present utility model.

[0025] In the figure: 1. outer shell; 10. end cover; 11. multi-section telescopic sleeve; 12. winding assembly; 120. winding box body; 121. winding shaft; 122. volute spring; 123. winding wire; 124. cylindrical cavity; 2. coil tube; 3. coil; 30. lead wire; 4. iron core; 5. slide rail; 50. slide groove; 51. slider; 6. guide assembly; 60. guide box body; 61. guide roller; 62. guide wire. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0027] Embodiment 1

[0028] Please see attached Figure 1-2 , a linear differential transformer displacement sensor, comprising:

[0029] A shell 1, a coil tube 2, a coil 3 and an iron core 4, wherein both ends of the shell 1 are provided with end covers 10 detachably connected thereto, the coil tube 2 is located in the shell 1, the coil 3 is wound on the coil tube 2, and the coil 3 is provided with a lead wire 30 integrally connected thereto, one end of the iron core 4 is located in the coil tube 2, and the other end passes through one of the end covers 10 of the shell 1 and is slidably connected thereto.

[0030] Specifically, epoxy resin is poured between the housing 1 and the coil 3;

[0031] The core 4 is driven to move axially by external force, during which the position of the core 4 in the coil tube 2 changes. When the core 4 is in different positions, the voltage change of the coil 3 is transmitted to the external detection device through the lead 30, and then the position change of the core 4 is determined.

[0032] Embodiment 2

[0033] Please see attached Figure 3

[0034] A multi-section telescopic sleeve rod 11 is provided on the end cover 10 that is not in contact with the iron core 4, one end of the multi-section telescopic sleeve rod 11 is fixedly connected to the end cover 10, and the other end is fixedly connected to the iron core 4;

[0035] Taking into account that in the prior art, the axial movement distance of the iron core 4 is usually limited to avoid the center of gravity of the iron core 4 moving to the outside of the shell 1, which indirectly limits the application of LVDT, a multi-section telescopic sleeve 11 is arranged in the coil tube 2. During the movement of the iron core 4, the multi-section telescopic sleeve 11 is stretched so that one end of the iron core 4 located in the coil tube 2 is always subjected to the tension from the multi-section telescopic sleeve 11, thereby avoiding the deflection of the iron core 4 and indirectly achieving the purpose of expanding the application scope of LVDT.

[0036] Embodiment 3

[0037] Please see attached Figure 4-5

[0038] Specifically, a winding assembly 12 is provided on the end cover 10 that is not in contact with the iron core 4, and the winding assembly 12 includes a winding box body 120, a winding shaft 121, at least one group of spiral springs 122 and a winding wire 123. The winding box body 120 is fixedly connected to the side wall of the end cover 10 away from the shell 1, and a cylindrical cavity 124 is provided in the winding box body 120. The two ends of the winding shaft 121 are respectively connected to the side walls of the cylindrical cavity 124 by bearings, and the two ends of the spiral spring 122 are respectively fixedly connected to the winding shaft 121 and the curved side walls of the cylindrical cavity 124. One end of the winding wire 123 is wound around the winding shaft 121, and the other end passes through the winding box body 120 and the end cover 10 and is fixedly connected to the iron core 4.

[0039] 123 is a kind of elastic member 124, and its elasticity is very good.

[0040] Embodiment 4

[0041] Please see attached Figure 6-7

[0042] Specifically, a slide rail 5 fixedly connected to the curved side wall of the housing 1 is provided, a slide groove 50 is provided on the slide rail 5, and a slider 51 slidably connected to the slide groove 50 is provided in the slide groove 50.

[0043] Specifically, a group of guide components 6 are respectively provided at both ends of the housing 1, and the guide components 6 include a guide box body 60, at least one group of guide rollers 61 and a guide wire 62. The guide box body 60 is fixedly connected to the end cover 10, and the guide roller 61 is located in the guide box body 60, and the bearings at both ends are connected to the inner wall of the guide box body 60. One end of the guide wire 62 passes through the end cover 10 and is fixedly connected to the iron core 4, and the other end passes around the guide roller 61 and passes through the side wall of the slide groove 50 and is fixedly connected to the slider 51.

[0044] When the slider 51 is displaced in the slide groove 50, it drives the movement of the iron core 4 through the guide wire 62. Considering that when the slider 51 moves, it can only apply tension to the guide wire 62 on one side of it, thereby driving the movement of the iron core 4, in order to avoid the situation where the iron core 4 can only move in one direction, two sets of guide components 6 are used, so that the slider 51 can drive the movement of the iron core 4 no matter in which direction it moves. The setting of the slider 5 and the guide component 6, through the cooperation of the guide wire 62 and the guide roller 61, solves the problem of needing to reserve axial movement space for the iron core 4 in advance in the traditional method, thereby expanding the application environment of LVDT.

[0045] Specifically, the length of the iron core 4 is smaller than that of the coil tube 2; considering that the length difference between the coil tube 2 and the iron core 4 is the movable distance of the iron core 4, the length of the iron core 4 must be smaller than that of the coil tube 2, otherwise the iron core 4 will be unable to move.

[0046] Specifically, a guide wire groove matching the guide wire 62 is provided on the curved side wall of the guide roller 61; in order to prevent the guide wire 62 from drifting on the guide roller 61 and getting stuck at the contact point between the guide roller 61 and the side wall of the guide box body 60, a wire groove is provided on the curved side wall of the guide roller 61 to restrict the guide wire 62.

[0047] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A linear differential transformer displacement sensor, characterized in that: include: A shell (1), a coil tube (2), a coil (3) and an iron core (4), wherein both ends of the shell (1) are provided with end covers (10) detachably connected thereto, the coil tube (2) is located in the shell (1), the coil (3) is wound on the coil tube (2), and the coil (3) is provided with a lead wire (30) integrally connected thereto, and one end of the iron core (4) is located in the coil tube (2), and the other end passes through one of the end covers (10) of the shell (1) and is slidably connected thereto.

2. The linear differential transformer displacement sensor according to claim 1, characterized in that: Epoxy resin is poured between the housing (1) and the coil (3).

3. The linear differential transformer displacement sensor according to claim 1, characterized in that: A multi-section telescopic sleeve rod (11) is provided on the end cover (10) not in contact with the iron core (4); one end of the multi-section telescopic sleeve rod (11) is fixedly connected to the end cover (10) and the other end is fixedly connected to the iron core (4).

4. The linear differential transformer displacement sensor according to claim 1, characterized in that: A winding assembly (12) is provided on the end cover (10) not in contact with the iron core (4), the winding assembly (12) comprising a winding box body (120), a winding shaft (121), at least one group of spiral springs (122) and a winding wire (123), the winding box body (120) being fixedly connected to a side wall of the end cover (10) away from the housing (1), and a cylindrical cavity (124) is provided in the winding box body (120). The two ends of the winding shaft (121) are respectively connected to the side wall of the cylindrical cavity (124) by bearings, the two ends of the spiral spring (122) are respectively fixedly connected to the winding shaft (121) and the curved side wall of the cylindrical cavity (124), one end of the winding wire (123) is wound around the winding shaft (121), and the other end passes through the winding box body (120) and the end cover (10) to be fixedly connected to the iron core (4).

5. The linear differential transformer displacement sensor according to claim 1, characterized in that: A slide rail (5) fixedly connected to the curved side wall of the housing (1) is provided, a slide groove (50) is provided on the slide rail (5), and a sliding block (51) slidably connected to the slide groove (50) is provided in the slide groove (50).

6. The linear differential transformer displacement sensor according to claim 5, characterized in that: A group of guide components (6) are respectively provided at both ends of the housing (1), and the guide components (6) include a guide box body (60), at least one group of guide rollers (61) and a guide wire (62). The guide box body (60) is fixedly connected to the end cover (10), the guide roller (61) is located in the guide box body (60), and bearings at both ends are connected to the inner wall of the guide box body (60), one end of the guide wire (62) passes through the end cover (10) and is fixedly connected to the iron core (4), and the other end passes around the guide roller (61) and then passes through the side wall of the slide groove (50) and is fixedly connected to the slider (51).

7. The linear differential transformer displacement sensor according to claim 6, characterized in that: The length of the iron core (4) is shorter than the length of the coil tube (2).

8. The linear differential transformer displacement sensor according to claim 6, characterized in that: A guide wire groove matching the guide wire (62) is provided on the curved side wall of the guide roller (61).

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