Scanning probe with damping function and three-coordinate measuring machine

Abstract

The present invention relates to the field of three-coordinate measurement technology, and specifically to a scanning probe with a damping function and a three-coordinate measuring machine. The scanning probe with a damping function includes a connecting member, a measuring needle, a detection assembly and a damping member. The connecting member includes a fixed part, a movable part and a flexible part. The movable part is movably connected to the fixed part through the flexible part; the measuring needle is connected to the movable part; the detection assembly includes a light source and a position sensor, one of the light source and the position sensor is arranged at the fixed part, and the other is arranged at the movable part; the damping member is used to absorb the vibration of the movable part after the measuring needle leaves the workpiece. When the measuring needle contacts the workpiece, the measuring needle drives the light source or the position sensor to move, and the light source and the position sensor deflect with each other. The position sensor generates a deflection signal based on the detected light deflection amount. The deflection signal is used to calculate the spatial coordinates of the contact point between the measuring needle and the workpiece. The damping member can provide damping for the movable part after the movable part leaves the workpiece to be measured, thereby preventing the movable part from vibrating continuously.

Description

Technical Field

[0001] The present invention relates to the technical field of three-coordinate measurement, and in particular to a scanning probe with a damping function and a three-coordinate measuring machine. Background Art

[0002] A coordinate measuring machine (CMM) is a precision measuring device used to accurately determine the geometric characteristics of an object in three dimensions, such as size, shape, angle, and position. The stylus is the core component of a CMM and typically consists of a probe body and a stylus. The stylus deflects upon contact with the workpiece to determine its spatial coordinates. The stylus is typically connected to the body with a flexible structure that provides a force to reset the stylus after it releases from the workpiece surface.

[0003] However, the stylus is prone to continuous vibration during the reset process after leaving the workpiece surface, and it takes a relatively long time to reset, which affects the measurement efficiency. Summary of the Invention

[0004] The present invention mainly solves the problem that the vibration of the measuring needle lasts for a long time after the measuring needle leaves the workpiece surface.

[0005] According to a first aspect, an embodiment provides a scanning probe with a damping function, comprising:

[0006] A connecting piece comprising a fixed portion, a movable portion and a flexible portion, wherein the movable portion is movably connected to the fixed portion via the flexible portion;

[0007] a stylus connected to the movable portion;

[0008] a detection component comprising a light source and a position sensor, wherein one of the light source and the position sensor is disposed on the fixed portion, and the other is disposed on the movable portion;

[0009] a damping member, provided on the fixed portion and / or the movable portion, for absorbing vibration of the movable portion after the stylus leaves the workpiece;

[0010] In which, when the stylus is not in contact with the workpiece, the flexible portion is used to drive the movable portion and the stylus to reset; when the stylus contacts the workpiece, the stylus drives the movable portion and the light source or the position sensor located on the movable portion to move, and the light source and the position sensor deflect relative to each other. The position sensor generates a corresponding deflection signal based on the detected light deflection amount, and the deflection signal is used to calculate the spatial coordinates of the contact point between the stylus and the workpiece.

[0011] In some embodiments, the movable part can swing relative to the fixed part and has a swing fulcrum, the connection position between the probe and the movable part is located at one end of the swing fulcrum, and the light source or the position sensor is located at the other end of the swing fulcrum.

[0012] In some embodiments, the flexible portion includes a first elastic layer and a second elastic layer axially spaced apart along the fixed portion, the first elastic layer allows the movable portion to move in the horizontal and axial directions, the second elastic layer is connected to the swing fulcrum and allows the movable portion to move in the axial direction, and the damping member is located between the first elastic layer and the second elastic layer.

[0013] In some embodiments, the damping member includes a magnet and a magnetofluid. The magnetofluid is disposed between the movable portion and the fixed portion and contacts the movable portion or the fixed portion. The magnet is used to apply a magnetic field to the magnetofluid to provide damping.

[0014] In some embodiments, the damping member includes a fixing frame, the fixing frame includes a connecting portion and a receiving portion, the connecting portion is fixedly connected to the fixing portion, and the receiving portion is used to receive the magnet.

[0015] In some embodiments, the fixing frame is made of soft magnetic material, the accommodating portion has an annular accommodating groove, the opening of the accommodating groove faces the movable portion, the magnet is located in the accommodating groove, and the two groove walls of the accommodating groove respectively form a first pole shoe and a second pole shoe.

[0016] In some embodiments, the first pole shoe is disposed closer to the first elastic layer than the second pole shoe, and a radial distance between the first pole shoe and the movable portion is greater than a radial distance between the second pole shoe and the movable portion.

[0017] In some embodiments, the radial distance between the magnet and the movable part is no greater than 5 mm.

[0018] In some embodiments, the magnet is a permanent magnet or an electromagnet.

[0019] According to the second aspect, an embodiment provides a three-coordinate measuring machine, characterized in that it includes a carrier platform, a driving mechanism and a scanning probe with a damping function as described in any of the above embodiments, the carrier platform is used to carry the workpiece to be measured; the scanning probe is located above the carrier platform, and the driving mechanism is used to drive the scanning probe to move along the X-axis direction, the Y-axis direction and the Z-axis direction.

[0020] In the scanning probe with damping function described above, the movable portion is connected to the fixed portion via a flexible portion. When the stylus contacts a workpiece, the movable portion deflects. Because one of the position sensor and the light source is located on the movable portion, and the other on the fixed portion, the relative positions of the light source and the position sensor shift when the movable portion deflects. The position sensor generates a deflection signal, which can be used to determine the stylus deflection and calculate the three-dimensional coordinates of the stylus at the time of contact with the workpiece. The damping element provides damping for the movable portion after it leaves the workpiece to prevent continued vibration of the movable portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A three-dimensional view of an embodiment of a coordinate measuring machine of the present invention;

[0022] Figure 2 A schematic diagram of a scanning probe with a damping function according to an embodiment of the present invention;

[0023] Figure 3 for Figure 2 A cross-sectional view of a first module of a scanning probe with a damping function;

[0024] Figure 4 for Figure 2 A cross-sectional view of a second module of a scanning probe having a damping function;

[0025] Figure 5 for Figure 4 A three-dimensional view of the damping element of the scanning probe with damping function;

[0026] Figure 6 for Figure 2 Cross-sectional view of the stylus of a scanning probe with damping function;

[0027] Figure 7 for Figure 2 A schematic structural diagram of the first elastic layer of the scanning probe with a damping function;

[0028] Figure 8 for Figure 2 A schematic structural diagram of the second elastic layer of the scanning probe with a damping function;

[0029] Figure 9 for Figure 2 FIG. 1 is a cross-sectional view of another embodiment of a second module of a scanning probe having a damping function, wherein the damping member between the first elastic layer and the second elastic layer is not shown.

[0030] Reference numerals:

[0031] 100, connector; 110, fixing portion; 111, first module; 1111, locking mechanism; 1112, electronic device; 1113, glass; 1114, positioning ball; 1115, electrical contact; 112, second module; 1121, inner shell; 1122, outer shell; 1123, slider; 1124, slot; 1125, latch; 1126, elastic member; 1127, positioning V-groove; 1128, conductive sheet; 1129, magnetic material; 120, movable portion; 130, flexible portion; 131, first elastic layer; 132, second elastic layer layer; 1321, adjustable area; 133, central area; 134, peripheral area; 135, gap; 200, measuring needle; 300, detection component; 310, light source; 312, position sensor; 313, aperture; 400, measuring head; 500, motion system; 510, X-axis; 520, Y-axis; 530, Z-axis; 600, supporting platform; 700, damping element; 710, magnet; 720, magnetorheological body; 730, fixing frame; 731, accommodating portion; 7311, accommodating groove; 7312, first pole shoe; 7313, second pole shoe. DETAILED DESCRIPTION

[0032] The present invention will be further described in detail below by means of specific embodiments in conjunction with the accompanying drawings. Similar elements in different embodiments are numbered with associated similar elements. In the following embodiments, many detailed descriptions are provided to enable the present application to be better understood. However, those skilled in the art will readily appreciate that some of the features may be omitted in different circumstances, or may be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification. This is to avoid the core portion of the present application being overwhelmed by excessive descriptions, and for those skilled in the art, it is not necessary to describe these related operations in detail. They will fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0033] In addition, the features, operations, or characteristics described in the specification may be combined in any appropriate manner to form various embodiments. Furthermore, the steps or actions in the method description may be reordered or adjusted in a manner readily apparent to those skilled in the art. Therefore, the various sequences in the specification and drawings are provided solely for the purpose of clearly describing a particular embodiment and are not intended to be mandatory, unless otherwise specified.

[0034] Component numbers used herein, such as "first" and "second," are used solely to distinguish the components being described and do not convey any sequential or technical meaning. References to "connection" and "coupling" herein, unless otherwise specified, include both direct and indirect connections (couplings).

[0035] like Figure 1 As shown, the three-dimensional coordinate measuring machine generally includes a probe 400, a motion system 500 and a carrier 600. The motion system 500 includes an X-axis 510 drive structure, a Y-axis 520 drive structure and a Z-axis 530 drive structure that are perpendicular to each other, which respectively control the relative movement of the probe 400 and the carrier 600 in the X-axis 510 direction, the Y-axis 520 direction and the Z-axis 530 direction.

[0036] Each drive structure is equipped with a grating scale and a reading head, which are used to record the current movement position of the X-axis 510 drive structure, the Y-axis 520 drive structure, and the Z-axis 530 drive structure in real time, that is, the current position of the probe 400. During the measurement process, the workpiece is placed on the carrier 600, and the motion system 500 controls the probe 400 to contact the workpiece. The position of the contact point between the probe 400 and the workpiece is recorded, thereby achieving the three-dimensional coordinate measurement of the workpiece.

[0037] According to the first aspect, if Figure 2-Figure 4 In one embodiment, a scanning probe with a damping function is provided, comprising a connector 100, a stylus 200, a detection assembly 300, and a damping element 700. The connector 100 is used to connect the stylus 200 to the Z-axis 530 of a coordinate measuring machine. Specifically, the connector 100 can be connected to the Z-axis 530 via a locking mechanism 1111. The specific structure of the locking mechanism 1111 is conventional and similar to that of patent CN119148156. The stylus 400 and the Z-axis 530 are detachably mounted by rotating a lock.

[0038] The connector 100 may include a fixed portion 110, a movable portion 120, and a flexible portion 130. The movable portion 120 is movably connected to the fixed portion 110 via the flexible portion 130, and the stylus 200 is connected to the movable portion 120. The fixed portion 110 can be understood as being fixed relative to the Z-axis 530, while the movable portion 120 can be understood as being movable relative to the fixed portion 110. Because the stylus 200 is connected to the movable portion 120, when the stylus 200 contacts the workpiece, it deflects, thereby driving the movable portion 120 to move.

[0039] The flexible portion 130 can take various forms. For example, the flexible portion 130 can be an elastic layer connected between the movable portion 120 and the fixed portion 110. The elastic layer can be made of an inherently elastic metal material, or gaps 135 can be machined into the elastic layer to further enhance its flexibility in any direction. In other embodiments, the elastic layer can also be a spring, a spring, or other elastically deformable structure.

[0040] The detection component 300 includes a light source 310 and a position sensor 312, one of which is arranged on the fixed part 110 and the other is arranged on the movable part 120. The position sensor 312 can be a PSD (Position Sensitive Detector) photoelectric position sensor. The measuring surface of the position sensor 312 can be arranged perpendicular to the movable part 120 and facing the light source 310, for receiving the light beam emitted by the light source 310. There can be one, two or more position sensors 312, and the central area of ​​at least one position sensor 312 is located near the axial position of the fixed part 110. The position sensor 312 can also be electrically connected to an electronic device 1112, which can include a multi-layer circuit board for processing the deflection signal of the position sensor.

[0041] The damping member 700 is arranged between the fixed part 110 and the movable part 120, and is used to absorb the vibration of the movable part 120 after the measuring needle 200 leaves the workpiece. As for the specific installation position of the damping member 700, it can be set on the fixed part 110, or on the movable part 120, or the damping member 700 or a part of the damping member 700 can be provided on both the fixed part 110 and the movable part 120. The specific form of the damping member 700 can be a contact damping structure, such as a spring, a spring or other structure that can absorb vibration through deformation. The damping member 700 can also be a structure having a magnetorheological structure. Alternatively, the damping member 700 can also be a non-contact electromagnetic structure. Preferably, the damping member 700 is a structure having a magnetorheological structure.

[0042] When the stylus 200 is not in contact with the workpiece, the flexible portion 130 is used to reset the movable portion 120 and the stylus 200. When the stylus 200 contacts the workpiece, the stylus 200 activates the movable portion 120 and the light source 310 or position sensor 312 located therein. The central regions of the light source 310 and position sensor 312 deflect relative to each other, and the position sensor 312 generates a corresponding deflection signal based on the amount of light deflection detected. The deflection signal is combined with the raster values ​​of the X-axis 510 drive structure, the Y-axis 520 drive structure, and the Z-axis 530 drive structure to calculate the spatial coordinates of the contact point between the stylus 200 and the workpiece. After the stylus 200 contacts and then releases the workpiece, the flexible portion 130 resets the movable portion 120 and the stylus 200. During the reset process, the stylus 200 and movable portion 120 may continue to vibrate. The damping element 700 absorbs this vibration, reducing the reset time.

[0043] In the scanning probe with damping function described above, the movable portion 120 is connected to the fixed portion 110 via the flexible portion 130. When the stylus 200 contacts a workpiece, the movable portion 120 deflects. Since one of the position sensor 312 and the light source 310 is located on the movable portion 120 and the other on the fixed portion 110, the relative positions of the light source 310 and the position sensor 312 shift when the movable portion 120 deflects. Consequently, the position sensor 312 generates a deflection signal, which can be used to determine the deflection of the stylus 200 and calculate the three-dimensional coordinates of the stylus 200 when it contacts the workpiece. The damping element 700 provides damping for the movable portion 120 after it leaves the workpiece to prevent continued vibration of the movable portion 120.

[0044] The above-mentioned scanning probe with damping function can accurately measure the deflection of the stylus 200 after contact with the workpiece. Furthermore, unlike the trigger-type probe 400, which detects stylus 200 deflection by switching on and off the circuit caused by the movement of the contact point, the above-mentioned scanning probe with damping function uses a deformable flexible portion 130 to allow stylus 200 to deflect. The position sensor 312 measures the stylus 200 deflection signal, and then calculates the spatial coordinates of the contact point based on the raster values ​​of the motion system 500. This avoids the problem of anisotropy in the stylus 400 caused by the electrical contact structure and the resulting short service life of the stylus 400.

[0045] It should be understood that the term "scanning probe" does not limit the use of the probe 400. First, because the scanning probe with a damping function of the present invention can measure the deflection of the stylus 200 in real time via the position sensor 312, the stylus 200 can move along the workpiece surface and perform a scanning operation, thereby quickly measuring each measurement point. In addition, the scanning probe with a damping function of the present invention can also be used for trigger measurement. Specifically, because the scanning probe can measure the deflection of the stylus 200 in real time via the position sensor 312, it can also identify the moment when the stylus 200 contacts the workpiece. When the scanning probe detects contact between the stylus 200 and the workpiece, the motion system 500 can be used to control the scanning probe to retract and record the raster values ​​of the X-axis 510 drive structure, the Y-axis 520 drive structure, and the Z-axis 530 drive structure at the time of contact to calculate the spatial coordinates of the contact point.

[0046] In some embodiments, as Figure 2-Figure 6 As shown, the movable part 120 can swing relative to the fixed part 110 and has a swing fulcrum. The connection position between the probe 200 and the movable part 120 is located at one end of the swing fulcrum, and the light source 310 or the position sensor 312 is located at the other end of the swing fulcrum.

[0047] When stylus 200 deflects upon contact with a workpiece, it deflects about the swing fulcrum, thereby causing the light source 310 or position sensor 312 at the other end of the swing fulcrum to deflect. Because either light source 310 or position sensor 312 is fixedly connected to the fixing portion 110, the deflection of stylus 200 causes the relative position of light source 310 or position sensor 312 to change, allowing position sensor 312 to generate a deflection signal.

[0048] In some embodiments, as Figure 4 As described, the flexible portion 130 includes a first elastic layer 131 and a second elastic layer 132 axially spaced apart along the fixed portion 110 , the first elastic layer 131 allows the movable portion 120 to move in the horizontal and axial directions, and the second elastic layer 132 is connected to the swing fulcrum and allows the movable portion 120 to move in the axial direction.

[0049] When the stylus 200 contacts a workpiece and is subjected to an axial force, the movable portion 120 can move in the axial direction. When the stylus 200 is subjected to a horizontal force, the movable portion 120 deflects, with the center of deflection located at the second elastic layer 132. When the stylus 200 is released from the workpiece, the flexible portion 130 provides a restoring force to reset the stylus 200.

[0050] The damping member 700 is located between the first elastic layer 131 and the second elastic layer 132. During the reset of the movable portion 120, the damping member 700 can quickly absorb the vibration energy of the movable portion 120, thereby reducing the reset time. Furthermore, the placement of the damping member 700 between the first elastic layer 131 and the second elastic layer 132 makes the structure of the connector 100 more compact.

[0051] In other embodiments, the damping member 700 may also be disposed on a side of the first elastic layer 131 away from the second elastic layer 132 , or on a side of the second elastic layer 132 away from the first elastic layer 131 .

[0052] In some embodiments, as Figure 4 and Figure 5 As shown, the damping member 700 includes a magnet 710 and a magnetofluid 720. The magnetofluid 720 is disposed between the movable portion 120 and the fixed portion 110. The magnet 710 is used to apply a magnetic field to the magnetofluid 720 to provide damping. Specifically, the magnet 710 can be disposed on the fixed portion 110, and the magnetofluid 720 is filled between the magnet 710 and the movable portion 120. The magnetofluid 720 can be attracted by the magnet 710 while in contact with the movable portion 120, providing damping to the movable portion 120.

[0053] In other embodiments, the magnet 710 may also be disposed on the movable portion 120 , and the space between the magnet 710 and the fixed portion 110 may be filled with a magnetorheological fluid 720 .

[0054] In some embodiments, as Figure 4 and Figure 5 As shown, the damping member 700 includes a fixed frame 730, which includes a connecting portion and a receiving portion 731. The connecting portion is fixedly connected to the fixed portion 110, and the receiving portion 731 is used to accommodate the magnet 710. The fixed frame 730 can be made of a metal material, such as iron, steel, or other magnetizable soft magnetic material. The receiving portion 731 has an annular receiving groove 7311, the opening of which faces the movable portion 120. The magnet 710 is located in the receiving groove 7311, and the two groove walls of the receiving groove 7311 respectively form a first pole shoe 7312 and a second pole shoe 7313.

[0055] Once magnet 710 is embedded in receiving groove 7311, it improves magnetic field distribution and prevents magnetofluid 720 from escaping the gap between magnet 710 and movable portion 120. Outflow refers to the magnetofluid 720 escaping from magnet 710 or flowing onto the outer surface of receiving portion 731 due to factors such as gravity or vibration. In other words, receiving portion 731 acts as a pole shoe to improve magnetic field distribution, retaining magnetofluid 720 between first pole shoe 7312 and second pole shoe 7313. This prevents magnetofluid 720 from escaping or spreading to other locations due to gravity, thereby improving long-term stability.

[0056] In addition, the arrangement of the accommodation portion 731 can also prevent the leakage of the magnetic field. After testing, it was found that almost no magnetic field could be detected outside the accommodation portion 731, thereby reducing the impact of the magnetic field on other devices.

[0057] In some embodiments, as Figure 4 and Figure 5 As shown, the first pole shoe 7312 is arranged closer to the first elastic layer 131 than the second pole shoe 7313 , and the radial distance between the first pole shoe 7312 and the movable part 120 is greater than the radial distance between the second pole shoe 7313 and the movable part 120 .

[0058] Because the center of deflection of the movable portion 120 is near the second elastic layer 132, the deflection amplitude of the movable portion 120 at the first pole shoe 7312 is greater than the deflection amplitude at the second pole shoe 7313. This difference in radial spacing between the pole shoe and the movable portion 120 does not hinder the deflection of the stylus 200. Furthermore, because the second pole shoe 7313 is located below the first pole shoe 7312 and the radial spacing between the second pole shoe 7313 and the movable portion 120 is smaller, the magnetofluid 720 is less likely to flow out due to gravity.

[0059] In some embodiments, the radial distance between the magnet 710 and the movable portion 120 is no greater than 5 mm. A smaller distance between the magnet 710 and the movable portion 120 can use less magnetorheological fluid 720 and reduce the risk of magnetorheological fluid 720 leaking out.

[0060] Magnet 710 is a permanent magnet or an electromagnet. While electromagnets can control the damping strength through current, permanent magnet 710 can reduce the number of electrical components in second module 112, or even make the entire second module 112 passive. This not only reduces costs but also reduces the impact of circuits on second module 112, thereby increasing the service life of second module 112. Preferably, magnet 710 is a permanent magnet.

[0061] In some embodiments, the axial distance between the swing fulcrum and the position sensor 312 is adjustable. It should be noted that after the axial distance between the swing fulcrum and the position sensor 312 is adjusted, the distance between the swing fulcrum and the position sensor 312 is fixed, and the scanning probe can operate normally.

[0062] The purpose of the above configuration is to match styluses 200 of different lengths. Specifically, during the measurement process, a constant measuring force is maintained between the stylus 200 and the workpiece surface to ensure consistent measurement conditions. However, the longer the stylus 200, the larger the lever arm. As a result, under the same measuring force, after the longer stylus 200 is deflected, the position change of the light source 310 at the upper end of the movable portion 120 decreases. In other words, the position change of the light spot on the position sensor 312 decreases, resulting in reduced resolution and affecting measurement accuracy. In theory, as long as the light spot does not move outside the position sensor, the larger the movable area of ​​the light spot, the higher the resolution and measurement accuracy.

[0063] For example, after deflecting a short stylus, the light spot position shifts by 10 pixels, while after deflecting the stylus 200 with the same force, the light spot position shifts by only 5 pixels, reducing the resolution by half. Therefore, the longer the stylus 200, the greater the distance between the second elastic layer 132 in the fixing portion 110 and the position sensor of the first module 111. Therefore, the distance between the swing fulcrum and the position sensor 312 needs to be adjusted for different styluses 200.

[0064] In some embodiments, as Figure 9As shown, the fixed portion 110 includes a first module 111 and a second module 112 connected axially. The stylus 200 is connected to the second module 112 and located at an end away from the first module 111. The position sensor 312 is fixed within the first module 111. The light source 310 is located within the second module 112 and fixedly connected to the movable portion 120. The movable portion 120 may be a stylus holder for fixing the stylus 200. The first module 111 is used to connect to the Z-axis 530. The locking mechanism 1111 described above may be provided in the first module 111. The first module 111 may also include an electronic device 1112, which may be located above the position sensor 312 and is used to process the deflection signal of the position sensor 312. In other embodiments, the light source 310 is fixed within the first module 111, and the position sensor 312 is fixedly connected to the movable portion 120.

[0065] The second module 112 includes an inner shell 1121 and an outer shell 1122. The movable portion 120 is connected to the inner shell 1121 via a flexible portion 130. The axial position of the inner shell 1121 relative to the outer shell 1122 is adjustable. Specifically, the inner shell 1121 and the outer shell 1122 may be cylindrical, with the outer shell 1122 being sleeved around the outer circumference of the inner shell 1121. At least two sliders 1123 are disposed between the inner shell 1121 and the outer shell 1122, spaced apart along the outer circumference of the inner shell 1121. Multiple sliders 1123 may be evenly spaced along the outer circumference of the inner shell 1121, thereby improving the coaxiality between the inner shell 1121 and the outer shell 1122.

[0066] An elastic pad is provided between at least one slider 1123 and the inner shell 1121 or the outer shell 1122. The purpose of providing the elastic pad is to pre-tighten the slider 1123 between the inner shell 1121 and the outer shell 1122, thereby achieving a gap-free connection between the inner shell 1121 and the outer shell 1122. Specifically, the elastic pad can be laid on a portion of the outer circumference of the inner shell 1121, and the slider can be fixed to the elastic pad to achieve a pre-tightening effect.

[0067] The thickness of at least one slider 1123 in the radial direction can be adjusted to maintain the coaxiality between the inner shell 1121 and the outer shell 1122. Specifically, the slider 1123 can be threadedly connected to the inner shell 1121 or the outer shell 1122 in the radial direction, so that the thickness of the slider 1123 protruding from the inner shell 1121 or the outer shell 1122, i.e., the above-mentioned radial thickness, can be adjusted by rotating the slider 1123. When the inner shell 1121 and the outer shell 1122 deviate from coaxiality, the coaxiality can be adjusted by rotating the slider 1123. In other embodiments, multiple sliders 1123 of different thicknesses can be prepared in advance and then sequentially installed between the inner shell 1121 and the outer shell 1122 to adjust the coaxiality between the inner shell 1121 and the outer shell 1122.

[0068] In some embodiments, the inner wall of the outer shell 1122 may be provided with an axially extending guide groove, and the inner shell 1121 may be provided with a matching axially extending guide protrusion to prevent rotation between the inner shell 1121 and the outer shell 1122. In the above-mentioned embodiment with a sliding block, only the axially extending guide groove may be provided on the inner wall of the outer shell 1122. In this case, the sliding block 1123 fixedly connected to the inner shell 1121 also serves as the aforementioned guide protrusion.

[0069] In some embodiments, as Figure 9 As shown, the outer wall of the inner shell 1121 may also be provided with a plurality of circumferentially extending slots 1124, which are spaced apart axially. Different slots 1124 are compatible with stylus pins 200 of different lengths. The outer shell 1122 may also be provided with at least one radially movable pin 1125, which can be inserted into the slot 1124 to define the axial position of the inner shell 1121, thereby defining the distance between the second elastic layer 132 of the second module 112 and the position sensor 312 of the first module 111. A plurality of pins 1125 may be provided, and these pins 1125 may be evenly spaced along the outer circumference of the outer shell 1122, thereby improving the uniformity of force applied to the flexible portion 130 in any direction.

[0070] In a specific embodiment, the slot 1124 may include a first slot and a second slot axially spaced from the first slot, with the second slot located below the first slot. When using a short stylus, the first slot is moved adjacent to the latch 1125 and inserted. When replacing a long stylus, the latch 1125 is released, and the second slot is moved adjacent to the latch 1125 and inserted. The position between the first and second slots can be calculated based on the light spot displacement caused by different styluses under the same measuring force, the size of the stylus, and the size of the movable portion 120.

[0071] The latch 1125 can be in the form of a jackscrew or an elastic ball plunger, and the latch 1125 is threadedly connected to the housing 1122. In other embodiments, the latch 1125 can also be a positioning block that can be radially inserted into the slot 1124. In this case, the latch 1125 and the housing 1122 are plug-connected.

[0072] In some embodiments, as Figure 9 As shown, an elastic member 1126, such as a spring, may be further provided between the inner shell 1121 and the top of the second module 112 to allow the inner shell 1121 to have an axial movement tendency, thereby eliminating the axial gap.

[0073] In some embodiments, at least two light sources 310 are disposed at the upper end of the movable portion 120. A stop 313 is provided in the direction in which the light beams from the light sources 310 are emitted. The light sources 310 and the stop 313 remain relatively stationary. After passing through the stop 313, the light beams emitted by different light sources 310 have different propagation directions, forming multiple light spots upon reaching the position sensor. When the movable portion 120 deflects, the positions of the light spots on the position sensor change due to changes in the positions of the light sources 310. This change in the positions of the light spots corresponds to the deflection of the stylus 200. Therefore, the deflection of the stylus 200, and therefore the contact position between the stylus 200 and the workpiece surface, can be calculated based on information from the position sensor 312.

[0074] The detection assembly 300 may also include focusing elements such as a focusing lens and a concave mirror, thereby enabling the focus position of the light beam to be near the position sensor 312, thereby reducing the size of the light spot. Since the smaller the light spot, the more accurately the position sensor can identify the light spot position, thereby improving the measurement accuracy. The focusing lens can be set between the aperture 313 and the position sensor 312. As for the concave mirror, the light source 310 can be fixed on the first module 111 and reflected to the position sensor 312 by the concave mirror located in the second module 112. The concave mirror is fixedly connected to the movable part 120.

[0075] In some embodiments, as Figure 2 As shown, the first module 111 and the second module 112 are detachably connected. One end of the first module 111 and the second module 112 connected is a first connection end. One end of the second module 112 and the first module 111 connected is a second connection end.

[0076] The middle area between the first and second connecting ends can be provided with a light-transmitting material, such as glass 1113, so that the light beam can pass through the light-transmitting material and illuminate the position sensor, while also preventing dust from entering the first module 111 and affecting measurement. In other embodiments, the middle area can also be provided with a through hole to allow the light beam to pass directly through.

[0077] A magnetic material 1129, such as a neodymium iron boron magnet 710, may be disposed in the middle region around the first or second connection end to achieve adsorption between the first module 111 and the second module 112. The magnetic material may be continuous around the middle region or may be composed of multiple segments arranged at intervals.

[0078] The first and second connection ends may also be provided with positioning pins and matching positioning grooves for preliminary positioning of the first and second modules 111, 112 before installation. Specifically, one of the first and second modules 111, 112 may be provided with a positioning pin, and the other may be provided with a positioning groove matching the outer shape of the positioning pin.

[0079] The first and second connecting ends may also be provided with at least two positioning balls 1114 and corresponding positioning V-grooves 1127 to facilitate positioning of the first and second modules 111, 112 during installation. Specifically, one of the first and second modules 111, 112 is provided with a positioning ball 1114, and the other is provided with a positioning V-groove 1127 that matches the shape of the positioning ball 1114. Preferably, three positioning balls 1114 are provided, evenly spaced, with a 120-degree angle between adjacent ones.

[0080] The first connection end and the second connection end may also be provided with an electrical contact 1115 and a conductive sheet 1128 for achieving electrical connection between the first module 111 and the second module 112, or for determining whether the second module 112 has been installed in the first module 111. Specifically, one of the first module 111 and the second module 112 is provided with an electrical contact 1115, and the other is provided with a conductive sheet 1128 for contacting the electrical contact 1115.

[0081] To determine whether the second module 112 has been installed on the first module 111, two electrical contacts 1115 can be provided. When the first module 111 and the second module 112 are connected, the two electrical contacts 1115 of the first module 111 come into contact with the conductive pad 1128 of the second module 112, forming a closed circuit. Therefore, whether the circuit is closed can be used to determine whether the second module 112 has been installed on the first module 111. In some embodiments, different styluses 200 are required to be equipped with different second modules 112. In this case, different second modules 112 can have different arrangements of electrical contacts 1115. Therefore, the first module 111 can determine the type of the currently connected second module 112 based on the conductive contacts.

[0082] In some embodiments, the second module 112 is detachably connected to the stylus 200. Since the positioning connection method of the second module 112 and the stylus 200 is similar to the connection method of the first module 111 and the second module 112 described above, it will not be repeated here.

[0083] In some embodiments, as Figure 4 As shown, the first elastic layer 131 is arranged closer to the light source 310 or position sensor 312 than the second elastic layer 132. Because the swing fulcrum is located on the second elastic layer 132, this arrangement increases the distance between the swing fulcrum and the light source 310 or position sensor 312. When the stylus 200 deflects, the light source 310 or position sensor 312 fixed at the upper end of the movable portion 120 is displaced more, that is, the relative displacement between the light source 310 and the position sensor 312 is greater, which helps improve measurement accuracy.

[0084] In other embodiments, the second elastic layer 132 is positioned closer to the light source 310 or position sensor 312 than the first elastic layer 131. Because the swing fulcrum is located on the second elastic layer 132, this arrangement increases the distance between the swing fulcrum and the end of the stylus 200. When the stylus 200 contacts a workpiece and experiences a severe collision, the longer force arm and the greater horizontal flexibility of the first elastic layer 131 compared to the second elastic layer 132 provide a better cushioning effect, reducing the risk of deformation of the stylus 200 and the movable portion 120.

[0085] In some embodiments, as Figure 4 、 Figure 7 and Figure 8 As shown, the first elastic layer 131 and the second elastic layer 132 each have a peripheral area 134, a central area 133 located within the peripheral area 134, and an elastic area located between the peripheral area 134 and the central area 133, the peripheral area 134 is connected to the fixed part 110, and the central area 133 is connected to the movable part 120.

[0086] The central region 133 of the elastic layer and the movable portion 120 may be connected by fasteners such as screws, adhesive bonding, welding, etc. Correspondingly, the peripheral region 134 of the elastic layer and the fixed portion 110 may be connected by fasteners such as screws, adhesive bonding, welding, etc.

[0087] In some embodiments, as Figure 4 、 Figure 7 and Figure 8 As shown, the area of ​​the central region 133 of the first elastic layer 131 is smaller than the area of ​​the central region 133 of the second elastic layer 132 , and the area of ​​the elastic region of the first elastic layer 131 is larger than the area of ​​the elastic region of the second elastic layer 132 .

[0088] Given that the first elastic layer 131 and the second elastic layer 132 are of the same size, the first elastic layer 131 has a smaller central region 133, which allows for a larger elastic area, thereby enhancing the first elastic layer 131's flexibility in both the horizontal and axial directions. The larger central region 133 of the second elastic layer 132 enhances its horizontal rigidity, while axial flexibility can be achieved by providing a longer circumferential gap 135 in its elastic area.

[0089] It should be noted that the second elastic layer 132 is not only flexible in the axial direction, but also has certain flexibility in the horizontal direction. However, compared with the first elastic layer 131, the second elastic layer 132 is less flexible in the horizontal direction.

[0090] In some embodiments, as Figure 4、 Figure 7 and Figure 8 As shown, the elastic regions of the first elastic layer 131 and the second elastic layer 132 are both provided with a gap 135, which extends from the central region 133 to the peripheral region 134. Specifically, the gap 135 may extend in a spiral shape, gradually extending from the central region 133 to the peripheral region 134. The gap 135 may be continuous or discontinuous, as long as it extends from the central region 133 to the peripheral region 134. The number of gaps 135 may be one or more.

[0091] In the direction from the central region 133 toward the peripheral region 134, the number of gaps 135 in the first elastic layer 131 is greater than the number of gaps 135 in the second elastic layer 132, and / or the width of the gaps 135 in the first elastic layer 131 is greater than the width of the gaps 135 in the second elastic layer 132. It can be understood that after the circumferentially extending gaps 135 are formed in the elastic region, the greater the number of circumferentially extending gaps 135 or the wider the gaps 135 in a specific horizontal direction, the easier it is for the movable portion 120 to move in that specific direction, i.e., the greater the flexibility in that direction. From another perspective, the more the elastic region is removed in the direction from the central region 133 toward the peripheral region 134, the greater the flexibility.

[0092] For example Figure 7 In the direction a shown in FIG, five gaps 135 can be considered to exist from the central region 133 to the peripheral region 134. These five gaps 135 facilitate movement of the central region 133 of the first elastic layer 131 relative to the peripheral region 134 in the direction a. Similarly, the gaps 135 shown in the figure facilitate movement of the central region 133 of the first elastic layer 131 relative to the peripheral region 134 in any horizontal direction.

[0093] It can be further understood that when the number of circumferentially extending gaps 135 of the first elastic layer 131 is greater than that of the second elastic layer 132, or the width of gaps 135 is greater, the first elastic layer 131 is more flexible in the horizontal direction, allowing the movable portion 120 to move horizontally. Secondly, the portion of the elastic region excluding gaps 135 can be defined as a connecting portion. The longer the circumferentially extending gaps 135, or the smaller the area of ​​the connecting portion near the circumferentially extending gaps 135, the easier it is for the movable portion 120 to move in the axial direction.

[0094] The gaps 135 of the first elastic layer 131 can extend from the central region 133 to the peripheral region 134. Therefore, the multiple gaps 135 allow the central region 133 to move axially relative to the peripheral region 134, while also allowing the movable portion 120 in the central region 133 to tilt. The gaps 135 of the second elastic layer 132 can extend from the central region 133 to the peripheral region 134. Therefore, the multiple gaps 135 allow the central region 133 to move axially relative to the peripheral region 134, while also allowing the movable portion 120 in the central region 133 to tilt. However, due to the different arrangement of these gaps 135, the movable portion 120 has less flexibility and a lower degree of freedom in the horizontal direction of the second elastic layer 132, resulting in the movable portion 120's deflection center remaining near the second elastic layer 132.

[0095] In some embodiments, the elastic region of the first elastic layer 131 is provided with at least two gaps 135, and the at least two gaps 135 are arranged symmetrically with respect to each other, so that the deflection resistance of the movable portion 120 in any horizontal direction is uniform. It will be appreciated that the symmetrical arrangement of the two gaps 135 allows the number and width of the gaps 135 to be as consistent as possible in any specific direction in the horizontal plane, thereby achieving highly consistent deflection resistance of the movable portion 120 in any specific direction.

[0096] like Figure 4 and Figure 7 As shown, the extension trajectory of the gap 135 can be an Archimedean spiral. When there are two gaps 135, the two gaps 135 can be arranged in a central symmetrical manner, that is, of the two gaps 135, one gap 135 extends clockwise and the other extends counterclockwise.

[0097] Furthermore, the proportional coefficient of the Archimedean spiral can be adjusted to adjust the distance between adjacent gaps 135 in the radial direction, thereby adjusting the elastic coefficients of the first elastic layer 131 in different directions. The purpose of adjusting the elastic coefficients in different directions is to ensure that the measuring force is approximately the same when the stylus 200 contacts the workpiece and deflects in different directions, thereby improving measurement accuracy. Conversely, because mechanical structures such as the stylus 200 and the movable portion 120 deform when subjected to force, if the measuring force varies when contacting the workpiece in different directions when measuring the same point on the workpiece, the stylus 200 may bend to varying degrees, which is detrimental to improving measurement accuracy and is an unavoidable drawback of the trigger probe 400.

[0098] In some embodiments, as Figure 8As shown, the gap 135 on the second elastic layer 132 is provided with an adjustable region 1321. The width of the gap 135 in the adjustable region 1321 is adjustable to adjust the elastic modulus of the second elastic layer 132 in the axial direction. The width of the gap 135 does not necessarily have to remain constant. For example, the shape of the gap 135 in the second elastic layer 132 can be adjusted. Specifically, the larger the width of the gap 135 in the adjustable region 1321, the smaller the elastic modulus of the second elastic layer 132 in the axial direction, i.e., the greater the flexibility; the smaller the width of the gap 135 in the adjustable region 1321, the larger the elastic modulus of the second elastic layer 132 in the axial direction, i.e., the less flexible it is. The width of the gap 135 in the adjustable region 1321 can be adjusted according to actual conditions.

[0099] It is understandable that the number of the adjustable areas 1321 on the gap 135 can be one, two, or more, and the size of the adjustable area 1321 can also be set according to actual needs.

[0100] According to the second aspect, an embodiment provides a three-dimensional coordinate measuring machine, characterized in that it includes a carrier platform 600, a driving mechanism and a scanning probe with a damping function of any of the above embodiments, the carrier platform 600 is used to carry the workpiece to be measured; the scanning probe is located above the carrier platform 600, and the driving mechanism is used to drive the scanning probe to move along the X-axis 510 direction, the Y-axis 520 direction and the Z-axis 530 direction.

[0101] The above examples are used to illustrate the present invention, which are only used to help understand the present invention and are not intended to limit the present invention. Those skilled in the art can make several simple deductions, modifications or substitutions based on the concept of the present invention.

Claims

1. A scanning probe with a damping function, characterized in that: include: A connecting piece comprising a fixed portion, a movable portion and a flexible portion, wherein the movable portion is movably connected to the fixed portion via the flexible portion; a stylus connected to the movable portion; a detection component comprising a light source and a position sensor, wherein one of the light source and the position sensor is disposed on the fixed portion, and the other is disposed on the movable portion; a damping member, provided on the fixed portion and / or the movable portion, for absorbing vibration of the movable portion after the stylus leaves the workpiece; When the stylus is not in contact with the workpiece, the flexible portion is used to drive the movable portion and the stylus to reset; when the stylus contacts the workpiece, the stylus drives the movable portion and the light source or the position sensor located on the movable portion to move, and the light source and the position sensor deflect relative to each other. The position sensor generates a corresponding deflection signal based on the detected light deflection amount, and the deflection signal is used to calculate the spatial coordinates of the contact point between the stylus and the workpiece; The movable portion is capable of swinging relative to the fixed portion and has a swing fulcrum, the connection position between the stylus and the movable portion is located at one end of the swing fulcrum, and the light source or the position sensor is located at the other end of the swing fulcrum; The flexible portion includes a first elastic layer and a second elastic layer spaced apart from each other axially along the fixed portion, the first elastic layer allowing the movable portion to move in the horizontal direction and the axial direction, the second elastic layer connected to the swing fulcrum and allowing the movable portion to move in the axial direction, and the damping member is located between the first elastic layer and the second elastic layer; The damping member includes a magnet and a magnetofluid. The magnetofluid is disposed between the movable portion and the fixed portion and contacts the movable portion or the fixed portion. The magnet is used to apply a magnetic field to the magnetofluid to provide damping.

2. The scanning probe with damping function according to claim 1, characterized in that: The damping member includes a fixing frame, and the fixing frame includes a connecting portion and a receiving portion. The connecting portion is fixedly connected to the fixing portion, and the receiving portion is used to receive the magnet.

3. The scanning probe with damping function according to claim 2, characterized in that: The fixing frame is made of soft magnetic material, the accommodating portion has an annular accommodating groove, the opening of the accommodating groove faces the movable portion, the magnet is located in the accommodating groove, and two groove walls of the accommodating groove respectively form a first pole shoe and a second pole shoe.

4. The scanning probe with damping function according to claim 3, characterized in that: The first pole shoe is disposed closer to the first elastic layer than the second pole shoe, and a radial distance between the first pole shoe and the movable portion is greater than a radial distance between the second pole shoe and the movable portion.

5. The scanning probe with damping function according to claim 1, characterized in that: The radial distance between the magnet and the movable part is no more than 5 mm.

6. The scanning probe with damping function according to claim 1, characterized in that: The magnet is a permanent magnet or an electromagnet.

7. A three-coordinate measuring machine, characterized in that: It comprises a carrier platform, a driving mechanism and a scanning probe with a damping function as described in any one of claims 1 to 6, wherein the carrier platform is used to carry a workpiece to be measured; the scanning probe is located above the carrier platform, and the driving mechanism is used to drive the scanning probe to move along the X-axis direction, the Y-axis direction and the Z-axis direction.

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