A force sensitive trigger probe with a ring microstructure optical fiber sensor

Abstract

The utility model discloses a kind of force-sensitive trigger probe of annular microstructure optical fiber sensing, it is related to precision measurement technical field, to solve the integration of existing probe structure and FBG sensor generally not high, the problem of limited measurement accuracy improvement;A kind of force-sensitive trigger probe of annular microstructure optical fiber sensing, including support unit, support unit is fixedly connected with annular sensitive unit, the central position of annular sensitive unit is provided with trigger probe unit, annular sensitive unit includes several rings, and sensitive beam is arranged between adjacent rings and between trigger probe unit and nearest ring, and optical fiber grating sensing module is arranged on sensitive beam.The utility model technical scheme considers sensitivity and stiffness, through the combination of multi-ring structure and sensitive beam, both ensure overall stiffness, and realize high sensitivity strain detection by sensitive beam.

Description

Technical Field

[0001] This utility model relates to the field of precision measurement technology, specifically to a force-sensitive trigger probe for annular microstructure fiber optic sensing. Background Technology

[0002] Nanoscale coordinate measuring instruments are widely used in precision measurement fields such as aerospace and automotive manufacturing, and are crucial equipment for achieving high-precision geometric measurements of complex components such as basic holes, microcavities, and tooth profiles. The force-sensitive trigger probe, as the core sensing component of a coordinate measuring machine (CMM), directly affects measurement sensitivity, stability, and reliability through its structural design. Most existing CMM probe supports employ single-ring, solid, or beam structures, which are simple in structure and have mature manufacturing processes, but suffer from drawbacks such as low sensitivity, high trigger signal noise, limited measurement scale, and poor anti-interference capabilities, severely restricting the extension of geometric measurement to high precision at the micro- and nano-scale; for example, CN211085181U. In recent years, fiber Bragg grating (FBG) sensing technology has been gradually applied to high-precision measurement fields due to its advantages such as high sensitivity, anti-electromagnetic interference, and small size. However, the integration of existing probe structures with FBGs is generally low, resulting in limited improvements in measurement accuracy. Utility Model Content

[0003] This invention addresses the problem that existing probe structures and FBG sensors generally have low integration and limited improvement in measurement accuracy. It proposes a force-sensitive trigger probe with a ring-shaped microstructure fiber optic sensing, which balances sensitivity and stiffness. The multi-ring structure is combined with a sensitive beam, which ensures overall stiffness while achieving high-sensitivity strain detection through the sensitive beam.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a force-sensitive trigger probe for annular microstructure fiber optic sensing, comprising a support unit, wherein an annular sensitive unit is fixedly connected to the support unit, a trigger probe unit is disposed at the center of the annular sensitive unit, the annular sensitive unit comprises several rings, and a sensitive beam is disposed between adjacent rings and between the trigger probe unit and the nearest ring, wherein a fiber optic grating sensing module is disposed on the sensitive beam.

[0005] In this technical solution, the support unit presents an annular hollow I-beam structure with high strength. The support unit is fixedly connected to the annular sensitive unit to fix the annular sensitive unit. A trigger probe unit is set at the center of the annular sensitive unit.

[0006] The present invention is further configured such that: the ring body includes an outer ring disposed on the outermost side and an inner ring disposed on the innermost side, and a first middle ring and a second middle ring are disposed sequentially between the outer ring and the inner ring.

[0007] In this technical solution, the ring body mainly includes an outer ring, a first middle ring, a second middle ring, and an inner ring, with the diameters of the outer ring, the first middle ring, the second middle ring, and the inner ring decreasing sequentially.

[0008] The present invention is further configured such that: the sensitive beam includes a transverse sensitive beam and a longitudinal sensitive beam, and separate transverse sensitive beams or longitudinal sensitive beams are installed between adjacent rings and between the trigger probe unit and the nearest ring.

[0009] The present invention is further configured such that: the trigger probe unit includes a central elastic base connected to the center of the annular sensitive unit, a central connector is provided on the lower end face of the central elastic base, an extension rod is fixedly connected to the central connector, and a trigger probe is provided on the end of the extension rod away from the central connector.

[0010] In this technical solution, the central elastic base is used to install the trigger probe through the central connector and the extension rod, and can transmit the deformation micro-stress of the trigger probe.

[0011] The present invention is further configured such that: a rigid connector is provided on the outer ring, the outer ring is fixedly connected to the central axis of the annular sensitive unit through the rigid connector, and a first transverse sensitive beam and a second transverse sensitive beam are connected to the other side of the outer ring, and the outer ring is flexibly connected to the first middle ring through the first transverse sensitive beam and the second transverse sensitive beam.

[0012] The present invention is further configured such that: a first longitudinal sensitive beam and a second longitudinal sensitive beam are connected to the side of the first middle ring away from the outer ring, and the first middle ring is flexibly connected to the second middle ring through the first longitudinal sensitive beam and the second longitudinal sensitive beam.

[0013] The present invention is further configured such that: a third transverse sensitive beam and a fourth transverse sensitive beam are connected to the side of the second middle ring away from the first middle ring, and the second middle ring is flexibly connected to the inner ring through the third transverse sensitive beam and the fourth transverse sensitive beam.

[0014] The present invention is further configured such that: a third longitudinal sensitive beam and a fourth longitudinal sensitive beam are connected to the side of the inner ring away from the second middle ring, and the inner ring is connected to the central elastic base through the third longitudinal sensitive beam and the fourth longitudinal sensitive beam.

[0015] The present invention is further configured such that: the support unit includes an outer support frame and an inner support frame, the outer support frame is fixedly connected to one side of the annular sensitive unit in the outer diameter direction, and the inner support frame is connected to the trigger probe.

[0016] The present invention is further configured such that: the support unit includes an outer support frame and an inner support frame, the outer support frame is fixedly connected to one side of the annular sensitive unit in the outer diameter direction, and the inner support frame is connected to the trigger probe.

[0017] This utility model can bring the following beneficial effects:

[0018] This invention relates to a force-sensitive trigger probe with a ring-shaped microstructure fiber optic sensing system, which balances sensitivity and stiffness. The combination of a multi-ring structure and a sensitive beam ensures overall stiffness while achieving high-sensitivity strain detection through the sensitive beam. Multi-point, multi-directional detection is achieved through the arrangement of the sensitive beam and fiber optic grating sensing module, enabling multi-directional, multi-point detection of minute forces and improving the probe's spatial resolution. The high degree of structural integration, with the support unit design providing excellent protection and support for the ring-shaped sensitive unit, facilitates mass production and assembly. The fiber optic grating sensing module directly senses the deformation of the sensitive beam, providing a strong signal and strong resistance to electromagnetic interference, making it suitable for high-precision measurements in complex environments. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the force-sensitive trigger probe of a ring-shaped microstructure fiber optic sensor according to this application.

[0020] Figure 2 This is a schematic diagram of the annular sensing unit and the trigger probe unit of this application.

[0021] Figure 3 This is a cross-sectional view of a force-sensitive trigger probe for a ring-shaped microstructure fiber optic sensing according to this application.

[0022] Figure 4 This is a top view of a force-sensitive trigger probe for a ring-shaped microstructure fiber optic sensing according to this application.

[0023] Figure 5 This is a schematic diagram of the installation of the trigger probe in this application.

[0024] Reference numerals: 1. Outer ring; 2. First middle ring; 3. Second middle ring; 4. Inner ring; 5. First transverse sensitive beam; 6. Second transverse sensitive beam; 7. Third transverse sensitive beam; 8. Fourth transverse sensitive beam; 9. First longitudinal sensitive beam; 10. Second longitudinal sensitive beam; 11. Third longitudinal sensitive beam; 12. Fourth longitudinal sensitive beam; 13. First fiber optic grating sensing module; 14. Second fiber optic grating sensing module; 15. Third fiber optic grating sensing module; 16. Fourth fiber optic grating sensing module; 17. Fifth fiber optic grating sensing module; 18. Sixth fiber optic grating sensing module; 19. Seventh fiber optic grating sensing module; 20. Eighth fiber optic grating sensing module; 21. Support unit; 22. Rigid connector; 23. Central connector; 24. Extension rod; 25. Trigger probe ball; 26. Central elastic base. Detailed Implementation

[0025] Example 1

[0026] This embodiment proposes a force-sensitive trigger probe for ring-shaped microstructure fiber optic sensing, referencing... Figure 1 , Figure 2 , Figure 3 , Figure 4 as well as Figure 5 It includes a support unit 21, an annular sensing unit, and a trigger probe unit; the support unit 21 is connected to the annular sensing unit, and a trigger probe unit is set at the center of the annular sensing unit. The annular sensing unit includes several rings and a sensing beam. The aforementioned sensing beam is set between adjacent rings and between the trigger probe unit and the nearest ring. A fiber optic grating sensing module is set on each sensing beam.

[0027] In this embodiment, the support unit 21 is designed as an annular hollow I-beam structure with high strength. It is located on the outermost side at one end. The support unit 21 is fixedly connected to the annular sensitive unit through a rigid connector 22 to fix the annular sensitive unit.

[0028] The multi-ring microstructure fiber optic trigger probe employs four concentric rings connected by several sensitive beams between the central body and the four rings, forming a multi-level support and force distribution path. The sensitive beams feature a high-sensitivity design, capable of undergoing minute elastic deformation under external forces, and integrate FBG sensors on their surfaces. The FBG sensors stretch or compress with the deformation of the sensitive beams, causing changes in the reflected wavelength, thus achieving high-sensitivity detection of minute forces and displacements. A cylindrical shell is located on the outermost ring, with four equally spaced rigid connectors on its inner upper and lower surfaces, further enhancing the overall stability and anti-interference capability of the structure. The central body of the force-sensitive trigger probe is equipped with a probe rod and a probe ball, effectively transmitting external forces to the sensitive beams for high-precision spatial coordinate acquisition.

[0029] This invention employs a multi-ring and sensitive beam collaborative structural design, significantly improving the symmetry and sensitivity of the force-sensitive trigger probe. The multi-ring structure effectively disperses external forces, prevents local stress concentration, and extends the probe's service life. The integrated design of the sensitive beam and FBG sensor concentrates the strain signal and makes it easy to detect, greatly improving measurement resolution and reliability. The external protection and support design of the cylindrical shell and rigid connecting parts enhances the structure's anti-interference capability. The overall structure has a high degree of integration, facilitating mass production and assembly, and making maintenance more convenient, suitable for the needs of modern manufacturing industries for high-precision, intelligent measurement equipment.

[0030] In this embodiment, the annular sensing unit includes four rings and eight sensing beams.

[0031] Reference 2 and Figure 4The ring body mainly includes an outer ring 1 on the outermost side, an inner ring 4 on the innermost side, and a first middle ring 2 and a second middle ring 3 between the outer ring 1 and the inner ring 4. The diameters of the outer ring 1, the first middle ring 2, the second middle ring 3 and the inner ring 4 decrease sequentially.

[0032] The sensitive beams mainly include transverse sensitive beams and longitudinal sensitive beams. Separate transverse or longitudinal sensitive beams are installed between adjacent rings and between the trigger probe unit and the nearest ring.

[0033] In this embodiment, both the transverse sensitive beam and the longitudinal sensitive beam are set as rectangular metal sheets, and their material has strict isotropy.

[0034] For the trigger probe unit, refer to Figure 1 , Figure 2 , Figure 3 as well as Figure 5 It includes a central elastic base 26, a central connector 27, an extension rod 24, and a trigger probe 25. The central elastic base 26 is fixedly connected to the annular sensitive unit. A corresponding central connector 23 is provided on the lower end face of the central elastic base 26. The central connector 23 is fixed to the extension rod 24. A corresponding trigger probe 25 is provided on the end of the extension rod 24 away from the central connector 23.

[0035] refer to Figure 5 In this embodiment, the central connector 23 and the extension rod 24 are specifically connected by threads, and the trigger probe 25 is fixedly connected to one end of the extension rod 24 by threads.

[0036] More specifically, a central connector 23 is provided at the lower center of the central elastic base 26. The central connector 23 has an M2.5 internal thread opening facing downward. One side of the extension rod 24 has an internal thread, and the other side has an external thread. The internal thread opening of the central connector 23 is connected in the same direction as the external thread of the extension rod 24. The trigger probe 25 is made of high-strength lightweight material. One side of the trigger probe is a thin rod with an external thread structure, and the other side is a spherical high-strength ball head. The trigger probe 25 is fixed to one end of the extension rod 24 by a threaded connection.

[0037] For the specific construction of the ring-shaped sensitive unit, refer to Figure 2 and Figure 4 The following is a detailed explanation.

[0038] A corresponding rigid connector 22 is also provided on the outer ring 1. The outer ring 1 is specifically fixedly connected to the central axis of the annular sensitive unit through the rigid connector 22 to fix the annular sensitive unit. A first transverse sensitive beam 5 and a second transverse sensitive beam 6 are provided and connected on the other side of the outer ring 1. The outer ring 1 is flexibly connected to the first middle ring 2 through the first transverse sensitive beam 5 and the second transverse sensitive beam 6.

[0039] In this embodiment, the first transverse sensitive beam 5 and the second transverse sensitive beam 6 are installed on both sides of the axis, and the first transverse sensitive beam 5 and the second transverse sensitive beam 6 are fixedly connected by a flexible hinge; the first transverse sensitive beam 5 and the second transverse sensitive beam 6 are respectively located on the radial sides of the first middle ring 2 and the outer ring 1.

[0040] The first middle ring 2 is provided with and connected to the first longitudinal sensitive beam 9 and the second longitudinal sensitive beam 10 on the side away from the outer ring 1. The first middle ring 2 is flexibly connected to the second middle ring 3 through the first longitudinal sensitive beam 9 and the second longitudinal sensitive beam 10.

[0041] In this embodiment, the other side of the first middle ring 2 is fixedly connected to the second middle ring 3 by a flexible hinge through the first longitudinal sensitive beam 9 and the second longitudinal sensitive beam 10 installed on both sides of the axis. The first longitudinal sensitive beam 9 and the second longitudinal sensitive beam 10 are located on the radial sides of the first middle ring 2 and the second middle ring 3, respectively.

[0042] The second middle ring 3 is provided on the side away from the first middle ring 2 and is connected to the third transverse sensitive beam 7 and the fourth transverse sensitive beam 8. The second middle ring 3 is flexibly connected to the inner ring 4 through the third transverse sensitive beam 7 and the fourth transverse sensitive beam 8.

[0043] In this embodiment, the other side of the second middle ring 3 is fixedly connected to the inner ring 4 by a flexible hinge through the third transverse sensitive beam 7 and the fourth transverse sensitive beam 8 installed on both sides of the axis. The third transverse sensitive beam 7 and the fourth transverse sensitive beam 8 are located on the radial sides of the second middle ring 3 and the inner ring 4, respectively.

[0044] The inner ring 4 is provided with and connected to the third longitudinal sensitive beam 11 and the fourth longitudinal sensitive beam 12 on the side away from the second middle ring 3. The inner ring 4 is connected to the central elastic base 26 through the third longitudinal sensitive beam 11 and the fourth longitudinal sensitive beam 12.

[0045] In this embodiment, the other side of the inner ring 4 is fixedly connected to the central elastic base 26 by a flexible hinge through the third longitudinal sensitive beam 11 and the fourth longitudinal sensitive beam 12 installed on both sides of the axis. The third longitudinal sensitive beam 11 and the fourth longitudinal sensitive beam 12 are located on the radial sides of the inner ring 4 and the central elastic base 26, respectively.

[0046] The support unit 21 includes an outer support frame and an inner support frame. The outer support frame is fixedly connected to one side of the outer diameter of the annular sensitive unit, and the inner support frame is connected to the trigger probe. It can support the vertical overload of the trigger probe and prevent its plastic deformation.

[0047] The fiber optic grating sensing module is fixedly installed along the axis of the sensing beam.

[0048] Example 2

[0049] This embodiment proposes a force-sensitive trigger probe for a ring-shaped microstructure fiber optic sensing system, comprising a support unit 21, a ring-shaped sensing unit, and a trigger probe unit. The support unit 21 is connected to the ring-shaped sensing unit, and the trigger probe unit is located at the center of the ring-shaped sensing unit. The ring-shaped sensing unit includes several rings and sensing beams. The aforementioned sensing beams are arranged between adjacent rings and between the trigger probe unit and the nearest ring. A fiber Bragg grating sensing module is arranged on each sensing beam. The sensing beams mainly include transverse sensing beams and longitudinal sensing beams. Individual transverse or longitudinal sensing beams are installed between adjacent rings and between the trigger probe unit and the nearest ring. Corresponding fiber Bragg grating sensing modules are arranged on both transverse and longitudinal sensing beams.

[0050] Based on Example 1, this example provides a detailed description of the fiber Bragg grating sensing module.

[0051] For fiber Bragg grating sensing modules, refer to Figure 2 and Figure 4 It includes a first fiber Bragg grating sensing module 13, a second fiber Bragg grating sensing module 14, a third fiber Bragg grating sensing module 15, a fourth fiber Bragg grating sensing module 16, a fifth fiber Bragg grating sensing module 17, a sixth fiber Bragg grating sensing module 18, a seventh fiber Bragg grating sensing module 19, and an eighth fiber Bragg grating sensing module 20.

[0052] Continue to refer to Figure 2 and Figure 4A first fiber Bragg grating sensing module 13 is fixedly installed on the first transverse sensitive beam 5 along the axial direction; a second fiber Bragg grating sensing module 14 is fixedly installed on the second transverse sensitive beam 6 along the axial direction; a third fiber Bragg grating sensing module 15 is fixedly installed on the third transverse sensitive beam 7 along the axial direction; a fourth fiber Bragg grating sensing module 16 is fixedly installed on the fourth transverse sensitive beam 8 along the axial direction; a fifth fiber Bragg grating sensing module 17 is fixedly installed on the first longitudinal sensitive beam 9 along the axial direction; and a sixth fiber Bragg grating sensing module 10 is fixedly installed on the second longitudinal sensitive beam 10 along the axial direction. 8. A seventh fiber optic grating sensing module 19 is fixedly installed on the third longitudinal sensitive beam 11 along the axial direction, and an eighth fiber optic grating sensing module 20 is fixedly installed on the fourth longitudinal sensitive beam 12 along the axial direction. The first fiber optic grating sensing module 13, the second fiber optic grating sensing module 14, the third fiber optic grating sensing module 15, the fourth fiber optic grating sensing module 16, the fifth fiber optic grating sensing module 17, the sixth fiber optic grating sensing module 18, the seventh fiber optic grating sensing module 19, and the eighth fiber optic grating sensing module 20 can all realize real-time measurement and correspond to the micro-strain of their respective sensitive beams.

[0053] The working principle of a force-sensitive trigger probe for a ring-shaped microstructure fiber optic sensing is described in detail.

[0054] During operation, when the ball head of the trigger probe 25 touches the workpiece being measured, the resulting lateral sway is transmitted to the central elastic base 26 through the extension rod 24. This causes each annular structure of the annular sensitive unit to deflect radially along the center. The amount of deflection is transmitted to the transverse and longitudinal sensitive beams connected to the annular structure, generating micro-strain. The micro-strain on each sensitive beam is measured by the optical Bragg grating sensing node fixed on it and transmitted to the data acquisition and control module (which has acquisition and calculation functions; the acquisition and calculation functions of the data acquisition and control module are existing technologies). This demodulates the strain signal. By fusing the eight strain signals, when the fused strain signal reaches the trigger threshold, the data acquisition and control module outputs a switch signal. After amplification by an amplifier, the signal controls the micro / nano coordinate measuring instrument to record the current coordinate position, thus achieving spatial coordinate measurement.

[0055] Compared with existing technologies, the advantages of this invention are: it balances sensitivity and stiffness, and the combination of the multi-ring structure and the sensitive beam ensures overall stiffness while achieving high-sensitivity strain detection through the sensitive beam; multi-point and multi-directional detection, with the arrangement of the sensitive beam and fiber optic grating sensing module, enables multi-directional and multi-point detection of minute forces, improving the spatial resolution of the probe; high structural integration, with the support unit design providing good protection and support for the ring-shaped sensitive unit, facilitating mass production and assembly; the fiber optic grating sensing module directly senses the deformation of the sensitive beam, providing a strong signal and strong anti-electromagnetic interference capability, making it suitable for high-precision measurement in complex environments.

Claims

1. A force-sensitive trigger probe for annular microstructure fiber optic sensing, characterized in that, Includes a support unit (21), which is fixedly connected to an annular sensitive unit. A trigger probe unit is provided at the center of the annular sensitive unit. The annular sensitive unit includes several rings. Sensitive beams are provided between adjacent rings and between the trigger probe unit and the nearest ring. Fiber grating sensing modules are provided on the sensitive beams.

2. The force-sensitive trigger probe for annular microstructure fiber optic sensing according to claim 1, characterized in that, The ring body includes an outer ring (1) on the outermost side and an inner ring (4) on the innermost side. A first middle ring (2) and a second middle ring (3) are arranged between the outer ring (1) and the inner ring (4).

3. The force-sensitive trigger probe for a ring-shaped microstructure fiber optic sensing according to claim 1 or 2, characterized in that, The sensitive beams include transverse sensitive beams and longitudinal sensitive beams, with separate transverse or longitudinal sensitive beams installed between adjacent rings and between the trigger probe unit and the nearest ring.

4. The force-sensitive trigger probe for annular microstructure fiber optic sensing according to claim 2, characterized in that, The trigger probe unit includes a central elastic base (26) connected to the center of the annular sensitive unit. A central connector (23) is provided on the lower end face of the central elastic base (26). An extension rod (24) is fixedly connected to the central connector (23). A trigger probe (25) is provided at one end of the extension rod (24) away from the central connector (23).

5. The force-sensitive trigger probe for annular microstructure fiber optic sensing according to claim 2, characterized in that, A rigid connector (22) is provided on the outer ring (1). The outer ring (1) is fixedly connected to the central axis of the annular sensitive unit through the rigid connector (22). A first transverse sensitive beam (5) and a second transverse sensitive beam (6) are connected on the other side of the outer ring (1). The outer ring (1) is flexibly connected to the first middle ring (2) through the first transverse sensitive beam (5) and the second transverse sensitive beam (6).

6. A force-sensitive trigger probe for annular microstructure fiber optic sensing according to claim 2 or 4, characterized in that, The first middle ring (2) is connected to a first longitudinal sensitive beam (9) and a second longitudinal sensitive beam (10) on the side away from the outer ring (1). The first middle ring (2) is flexibly connected to the second middle ring (3) through the first longitudinal sensitive beam (9) and the second longitudinal sensitive beam (10).

7. A force-sensitive trigger probe for annular microstructure fiber optic sensing according to claim 2 or 4, characterized in that, The second middle ring (3) is connected to the third transverse sensitive beam (7) and the fourth transverse sensitive beam (8) on the side away from the first middle ring (2). The second middle ring (3) is flexibly connected to the inner ring (4) through the third transverse sensitive beam (7) and the fourth transverse sensitive beam (8).

8. The force-sensitive trigger probe for annular microstructure fiber optic sensing according to claim 4, characterized in that, The inner ring (4) is connected to the third longitudinal sensitive beam (11) and the fourth longitudinal sensitive beam (12) on the side away from the second middle ring (3). The inner ring (4) is connected to the central elastic base (26) through the third longitudinal sensitive beam (11) and the fourth longitudinal sensitive beam (12).

9. The force-sensitive trigger probe for annular microstructure fiber optic sensing according to claim 4, characterized in that, The support unit (21) includes an outer support frame and an inner support frame. The outer support frame is fixedly connected to one side of the outer diameter of the annular sensitive unit, and the inner support frame is connected to the trigger probe.

10. The force-sensitive trigger probe for annular microstructure fiber optic sensing according to claim 1, characterized in that, The fiber grating sensing module is specifically fixedly installed along the axis of the sensing beam.

Images