A linear displacement sensor

Abstract

The utility model provides a linear displacement sensor relates to displacement measurement equipment technical field, including shell body and install in the metal induction piece of measured body, be equipped with with the PCB board that metal induction piece corresponds in the shell body, PCB board is equipped with exciting coil, first induction coil group and second induction coil group, first induction coil group and second induction coil group are arranged respectively in different PCB layer, and exciting coil is arranged in any PCB layer, and the period of first induction coil group is integer times of second induction coil group, the utility model provides sets up two induction coil groups and shares a metal induction piece, and sets up the period of an induction coil group is integer times of another induction coil group, thereby can keep measurement accuracy when the measurement range increases, improves sensor overall measurement accuracy.

Description

Technical Field

[0001] This utility model relates to the field of displacement measurement equipment technology, and in particular to a linear displacement sensor. Background Technology

[0002] Linear displacement sensors convert linear mechanical displacement into electrical signals, which are then used by an induction coil within the sensor to measure the position of a moving metal induction plate, thereby determining the precise location of the object on which the metal induction plate is mounted. However, existing linear displacement sensors generally suffer from a technical problem: increasing the measurement range leads to a decrease in accuracy, while increasing accuracy leads to a decrease in the measurement range. Utility Model Content

[0003] To address the problems existing in the prior art, this utility model provides a linear displacement sensor that maintains measurement accuracy even as the measurement range increases, thereby improving the overall measurement accuracy of the sensor.

[0004] This utility model proposes a linear displacement sensor, including a housing and a metal sensing element installed on the object being measured. The housing is provided with a PCB board corresponding to the metal sensing element. The PCB board is provided with an excitation coil, a first induction coil group and a second induction coil group. The first induction coil group and the second induction coil group are respectively disposed on different PCB layers, and the excitation coil is disposed on any PCB layer. The period of the first induction coil group is an integer multiple of that of the second induction coil group.

[0005] Preferably, the linear displacement sensor provided by this utility model includes three induction coils arranged in a staggered manner in both the first induction coil group and the second induction coil group.

[0006] Preferably, the linear displacement sensor provided by this utility model has a PCB groove inside the housing, and the PCB board is installed in the PCB groove.

[0007] Preferably, the linear displacement sensor provided by this utility model has mounting holes on both sides of the housing.

[0008] Preferably, the linear displacement sensor provided by this utility model has mounting steps on both sides of the housing, and mounting holes are provided in the mounting steps.

[0009] Preferably, the linear displacement sensor provided by this utility model has a housing mounted on a detection mechanism, and the detection mechanism has connection holes on both sides corresponding to the mounting holes.

[0010] Preferably, the linear displacement sensor provided by this utility model has a sliding groove in the detection mechanism, and a sliding movable part is provided in the sliding groove; one end of the movable part is connected to the measured object, and the other end of the movable part is connected to the metal sensing element.

[0011] Preferably, in the linear displacement sensor provided by this utility model, the metal sensing element is a metal sensing sheet.

[0012] Preferably, the linear displacement sensor provided by this utility model has a cover plate installed on the top of the housing.

[0013] Preferably, the linear displacement sensor provided by this utility model has an electrical connector connected to its outer shell, and the electrical connector is connected to the PCB board through an electrical connector.

[0014] As can be seen, the linear displacement sensor provided by this utility model sets two induction coil groups to share a metal induction sheet, and sets the period of one induction coil group to be an integer multiple of the period of the other induction coil group, so as to maintain measurement accuracy even when the measurement range increases, thereby improving the overall measurement accuracy of the sensor. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 The diagram shows a frame schematic of a linear displacement sensor according to an embodiment of this utility model; Figure 2 The diagram shown is an exploded view of a linear displacement sensor according to an embodiment of this utility model. Figure 3 The diagram shows the structure of two sets of induction coils in an embodiment of this utility model. Figure 4 The diagram shows the measurement range of the two sets of induction coils in this embodiment of the present invention. Figure 5 This diagram illustrates the normalized signal output of two sets of induction coils in an embodiment of this invention.

[0017] The reference numerals in the accompanying drawings are as follows: The outer casing 1, PCB slot 11, mounting hole 12, mounting step 13, cover plate 14, electrical connector 15, metal sensing element 2, PCB board 3, excitation coil 31, first induction coil group 32, second induction coil group 33, detection mechanism 4, connection hole 41, slide 42, moving part 43. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0019] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0020] In existing technologies, linear displacement sensors generally suffer from the technical problem that increasing the measurement range leads to decreased accuracy, while increasing accuracy leads to a smaller measurement range. This utility model provides the following solution: like Figure 1 and Figure 2 As shown, this embodiment of the present invention provides a linear displacement sensor, including a housing 1 and a metal sensing element 2 mounted on the object being measured. The housing 1 contains a PCB board 3 corresponding to the metal sensing element 2. The PCB board 3 has an excitation coil 31, a first induction coil group 32, and a second induction coil group 33. The first induction coil group 32 and the second induction coil group 33 are respectively disposed on different PCB layers, and the excitation coil 31 is disposed on any PCB layer, such as any layer of a two-layer PCB board or any layer of a four-layer PCB board. The period of the first induction coil group 32 is an integer multiple of the period of the second induction coil group 33.

[0021] It should be noted that the metal sensor 2 can be a metal induction sheet, and the measuring stroke of the first induction coil group 32 is an integer multiple of that of the second induction coil group 33. When detecting the position of the object being measured, the metal sensor 2 moves along with the object. The excitation coil 31 inputs alternating signals to the first induction coil group 32 and the second induction coil group 33 respectively. When the metal sensor 2 moves to the first induction coil group 32 and the second induction coil group 33, two sets of induction signals with different periods are generated. The position of the metal sensor, i.e., the position of the object being measured, can be obtained from the induction signals. It can be understood that the position calculated based on the first set of signals has relatively low accuracy, but it can determine which cycle of the second induction coil group is accurate; the position calculated based on the second set of signals has relatively high accuracy, but it can determine the relative position within the current cycle of the second induction coil group. Thus, the precise position within the entire measurement range can be obtained.

[0022] In some embodiments, both the first induction coil group 32 and the second induction coil group 33 include three induction coils arranged in a staggered manner, such as... Figure 3 As shown, the induction coils of the first induction coil group 32 are represented by U1, U2 and U3 respectively, and the induction coils of the second induction coil group 33 are represented by U1', U2' and U3' respectively.

[0023] It should be noted that setting up three staggered induction coils can prevent interference with the output signal when there are any changes in the excitation current or any changes in various mechanical parameters (the distance, angle, and tilt between the metal sensing element and the induction coil), and can also ensure that the output signal has sufficient linearity.

[0024] In some embodiments, the period of the first induction coil group 32 is twice that of the second induction coil group 33, such as... Figure 4 As shown, the measuring stroke L1 of the first induction coil group 32 is twice the measuring stroke L2 of the second induction coil group 33. Figure 5 As shown, the top image shows the normalized signal output by the first induction coil group 32, and the bottom image shows the normalized signal output by the second induction coil group 33.

[0025] In some embodiments, the housing 1 is provided with a PCB slot 11, and the PCB board 3 is installed in the PCB slot 11, thereby enabling the PCB board 3 to be installed more stably.

[0026] In some embodiments, mounting steps 13 are provided on both sides of the outer casing 1, and mounting holes 12 are disposed within the mounting steps 13. The outer casing 1 is mounted on the detection mechanism 4, and the detection mechanism 4 has connecting holes 41 on both sides corresponding to the mounting holes 12.

[0027] Understandably, the housing 1 can be more securely fixed to the detection mechanism 4 by installing connectors in the mounting hole 12 and the connection hole 41. These connectors include bolts, rivets, and clips.

[0028] In some embodiments, the detection mechanism 4 is provided with a groove 42, and a slidable movable member 43 is provided within the groove 42. One end of the movable member 43 is connected to the object being measured, and the other end of the movable member 43 is connected to the metal sensor 2.

[0029] In some embodiments, a cover plate 14 is installed on the top of the outer casing 1 to protect the PCB board 3. In other embodiments, potting is used on the top of the outer casing 1 to protect the PCB board 3.

[0030] In some embodiments, the housing 1 is connected to an electrical connector 15, which is connected to the PCB board 3 via an electrical connector. It should be noted that the electrical connector 15 is used for data transmission from external devices. The electrical connector 15 can be connected to one end of the housing 1 or to the middle of the housing 1. Alternatively, the electrical connector 15 can be directly led out using a wire, with one end of the wire connected to the PCB board 3 and the other end connected to the electrical connector 15.

[0031] In summary, the embodiments of this utility model provide a linear displacement sensor that sets two induction coil groups to share a single metal induction sheet, and sets the period of one induction coil group to be an integer multiple of that of the other induction coil group, thereby maintaining measurement accuracy even as the measurement range increases, and improving the overall measurement accuracy of the sensor.

[0032] The above description is merely a specific embodiment of this application, and the scope of protection of this application is not limited thereto. Those skilled in the art can make changes or substitutions within the technical scope disclosed in this application, and all such changes or substitutions should be within the scope of protection of this application.

[0033] Those skilled in the art will understand that although some embodiments described herein include certain features included in other embodiments but not others, combinations of features from different embodiments are meant to be within the scope of this invention and form different embodiments.

[0034] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A linear displacement sensor, characterized in that, The device includes an outer casing (1) and a metal sensor (2) installed on the object being measured. The outer casing (1) contains a PCB board (3) corresponding to the metal sensor (2). The PCB board (3) contains an excitation coil (31), a first induction coil group (32), and a second induction coil group (33). The first induction coil group (32) and the second induction coil group (33) are respectively disposed on different PCB layers. The excitation coil (31) is disposed on any PCB layer. The period of the first induction coil group (32) is an integer multiple of the period of the second induction coil group (33).

2. The linear displacement sensor according to claim 1, characterized in that, The first induction coil group (32) and the second induction coil group (33) each include three induction coils arranged in a staggered manner.

3. The linear displacement sensor according to claim 1, characterized in that, The outer casing (1) is provided with a PCB slot (11), and the PCB board (3) is installed in the PCB slot (11).

4. The linear displacement sensor according to claim 1, characterized in that, The outer casing (1) has mounting holes (12) on both sides.

5. The linear displacement sensor according to claim 4, characterized in that, The outer shell (1) is provided with mounting steps (13) on both sides, and the mounting hole (12) is provided in the mounting step (13).

6. The linear displacement sensor according to claim 4, characterized in that, The outer shell (1) is installed on the detection mechanism (4), and the detection mechanism (4) has connection holes (41) on both sides corresponding to the mounting hole (12).

7. The linear displacement sensor according to claim 6, characterized in that, The detection mechanism (4) is provided with a slide groove (42), and a sliding movable part (43) is provided in the slide groove (42); one end of the movable part (43) is connected to the object being tested, and the other end of the movable part (43) is connected to the metal sensing element (2).

8. The linear displacement sensor according to claim 1, characterized in that, The metal sensing element (2) is a metal sensing sheet.

9. The linear displacement sensor according to claim 1, characterized in that, The top of the outer casing (1) is fitted with a cover plate (14).

10. The linear displacement sensor according to claim 1, characterized in that, The outer casing (1) is connected to an electrical connector (15), which is connected to the PCB board (3) via an electrical connector.

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