Scanning probe with damping function and three-coordinate measuring machine

Abstract

The invention relates to the technical field of three-coordinate measurement, in particular to a scanning probe with a damping function and a three-coordinate measuring machine. The scanning probe with the damping function comprises a connecting piece, a probe, a detection assembly and a damping piece, the connecting piece comprises a fixed part, a movable part and a flexible part, and the movable part is movably connected with the fixed part through the flexible part; the probe is connected with the movable part; the detection assembly comprises a light source and a position sensor, one of the light source and the position sensor is arranged on the fixed part, and the other is arranged on the movable part; and the damping piece is used for absorbing the vibration of the movable part after the probe leaves the workpiece. When the probe is in contact with the workpiece, the probe drives the light source or the position sensor to move, the light source and the position sensor deflect mutually, the position sensor generates a deflection signal according to the detected light deflection amount, and the deflection signal is used for calculating the space coordinates of the contact point of the probe and the workpiece. The damping piece can provide damping for the movable part after the movable part leaves the to-be-tested workpiece, and continuous vibration of the movable part is avoided.

Description

Technical Field

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

[0002] A three - coordinate measuring machine is a precision measuring device used to accurately determine the geometric features of an object in three - dimensional space, such as parameters like dimensions, shapes, angles, and positions. The probe is the core component of the three - coordinate measuring machine, generally including a probe body and a probe needle. The probe needle deflects after contacting the workpiece to be measured to determine its spatial coordinates. The probe needle is usually connected to the probe body by a flexible structure, and the flexible structure can provide a restoring force for the probe needle after the probe needle leaves the surface of the workpiece.

[0003] However, during the process of the above - mentioned probe needle restoring after leaving the surface of the workpiece, it is prone to continuous vibration and requires a relatively long time to restore, which affects the measurement efficiency. Summary of the Invention

[0004] The present invention mainly solves the problem that the vibration duration of the probe needle is relatively long after leaving the surface of the workpiece.

[0005] According to a first aspect, in one embodiment, a scanning probe with a damping function is provided, including: A connecting member, including a fixed part, a movable part, and a flexible part, the movable part is movably connected to the fixed part through the flexible part; A probe needle, connected to the movable part; A detection component, including a light source and a position sensor, one of the light source and the position sensor is arranged on the fixed part, and the other is arranged on the movable part; A damping member, arranged on the fixed part and / or the movable part, for absorbing the vibration of the movable part after the probe needle leaves the workpiece; Wherein, when the probe needle does not contact the workpiece, the flexible part is used to drive the movable part and the probe needle to restore. When the probe needle contacts the workpiece, the probe needle drives the movable part and the light source or the position sensor located on the movable part to move, the light source and the position sensor deflect relative to each other, and the position sensor generates a corresponding deflection signal according to the detected light deflection amount, and the deflection signal is used to calculate the spatial coordinates of the contact point between the probe needle and the workpiece.

[0006] In some embodiments, the movable part can swing relative to the fixed part and has a swing fulcrum. The connection position of the probe needle 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.

[0007] In some embodiments, the flexible part includes a first elastic layer and a second elastic layer arranged axially spaced along the fixed part. The first elastic layer allows the movable part to move in the horizontal direction and the axial direction. The second elastic layer is connected to the swing fulcrum and allows the movable part to move in the axial direction. The damping member is located between the first elastic layer and the second elastic layer.

[0008] In some embodiments, the damping member includes a magnet and a magnetorheological fluid. The magnetorheological fluid is disposed between the movable part and the fixed part and is in contact with the movable part or the fixed part. The magnet is used to apply a magnetic field to the magnetorheological fluid to provide damping.

[0009] In some embodiments, the damping member includes a fixing bracket. The fixing bracket includes a connecting part and a receiving part. The connecting part is fixedly connected to the fixed part. The receiving part is used to receive the magnet.

[0010] In some embodiments, the fixing bracket is made of a soft magnetic material. The receiving part has an annular receiving groove. The opening of the receiving groove faces the movable part. The magnet is located in the receiving groove. Two groove walls of the receiving groove respectively form a first pole shoe and a second pole shoe.

[0011] In some embodiments, the first pole shoe is arranged closer to the first elastic layer than the second pole shoe, and the radial distance between the first pole shoe and the movable part is greater than the radial distance between the second pole shoe and the movable part.

[0012] In some embodiments, the radial distance between the magnet and the movable part is not greater than 5 millimeters.

[0013] In some embodiments, the magnet is a permanent magnet or an electromagnet.

[0014] According to a second aspect, an embodiment provides a coordinate measuring machine, which is characterized by including a carrying table, a driving mechanism, and a scanning probe head with a damping function according to any one of the above embodiments. The carrying table is used to carry a workpiece to be measured. The scanning probe head is located above the carrying table. The driving mechanism is used to drive the scanning probe head to move in the X-axis direction, the Y-axis direction, and the Z-axis direction.

[0015] According to the scanning probe with damping function in the above embodiments, the movable part is connected to the fixed part through the flexible part. When the probe tip contacts the workpiece, the movable part can deflect. Since one of the position sensor and the light source is arranged on the movable part and the other is arranged on the fixed part, when the movable part deflects, the relative position of the light source and the position sensor will move. Furthermore, the position sensor can generate a deflection signal, and then the deflection amount of the probe tip can be obtained through the deflection signal to calculate the three-dimensional coordinates when the probe tip contacts the workpiece. The damping member can provide damping for the movable part after the movable part leaves the workpiece to be measured, avoiding continuous vibration of the movable part. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Stereoscopic view of an embodiment of the coordinate measuring machine of the present invention; Figure 2 Exploded view of an embodiment of the scanning probe with damping function of the present invention; Figure 3 is Figure 2 Cross-sectional view of the first module of the scanning probe with damping function in; Figure 4 is Figure 2 Cross-sectional view of the second module of the scanning probe with damping function in; Figure 5 is Figure 4 Stereoscopic view of the damping member of the scanning probe with damping function in; Figure 6 is Figure 2 Cross-sectional view of the probe tip of the scanning probe with damping function in; Figure 7 is Figure 2 Structural schematic diagram of the first elastic layer of the scanning probe with damping function in; Figure 8 is Figure 2 Structural schematic diagram of the second elastic layer of the scanning probe with damping function in; Figure 9 is Figure 2 Cross-sectional view of another embodiment of the second module of the scanning probe with damping function in, in which the damping member between the first elastic layer and the second elastic layer is not shown in the figure.

[0017] Reference Signs: 100, Connecting piece; 110, Fixing part; 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, Slide block; 1124, Card slot; 1125, Plug pin; 1126, Elastic member; 1127, Positioning V-groove; 1128, Conductive sheet; 1129, Magnetic material; 120, Movable part; 130, Flexible part; 131, First elastic layer; 132, Second elastic layer; 1321, Adjustable area; 133, Central area; 134, Outer peripheral area; 135, Gap; 200, Probe; 300, Detection assembly; 310, Light source; 312, Position sensor; 313, Diaphragm; 400, Probe head; 500, Motion system; 510, X-axis; 520, Y-axis; 530, Z-axis; 600, Carrying platform; 700, Damping member; 710, Magnet; 720, Magnetorheological fluid; 730, Fixing bracket; 731, Accommodating part; 7311, Accommodating groove; 7312, First pole shoe; 7313, Second pole shoe. Detailed implementation manners

[0018] The present invention will be further described in detail below in conjunction with the accompanying drawings through specific implementation manners. Similar elements in different implementation manners are labeled with related similar element numbers. In the following implementation manners, many detailed descriptions are provided to enable a better understanding of the present application. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can 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 to avoid the core part of the present application being overwhelmed by excessive descriptions. For those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the descriptions in the specification and general technical knowledge in the art.

[0019] In addition, the features, operations, or characteristics described in the specification can be combined in any appropriate manner to form various implementation manners. At the same time, the steps or actions in the method description can also be reordered or adjusted in an obvious manner by those skilled in the art. Therefore, the various sequences in the specification and drawings are only for clearly describing a certain embodiment and do not mean that they are the necessary sequences unless it is stated that a certain sequence must be followed.

[0020] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the described objects and do not have any sequential or technical meanings. And the "connection" and "coupling" mentioned in the present application, unless otherwise specified, both include direct and indirect connection (coupling).

[0021] As Figure 1 shown, a coordinate measuring machine generally includes a probe 400, a motion system 500 and a carrier 600. The motion system 500 includes X-axis 510 driving structures, Y-axis 520 driving structures and Z-axis 530 driving structures that are perpendicular to each other, and respectively control the relative movement of the probe 400 and the carrier 600 in the X-axis 510 direction, Y-axis 520 direction and Z-axis 530 direction.

[0022] Each driving structure is provided with a grating scale and a reading head for real-time recording of the moving positions of the current X-axis 510 driving structure, Y-axis 520 driving structure and Z-axis 530 driving structure, that is, the current position of the probe 400. During the measurement process, the workpiece is placed on the carrier 600, and the probe 400 is controlled to contact the workpiece through the motion system 500, and the position of the contact point when the probe 400 contacts the workpiece is recorded, thereby realizing the three-dimensional coordinate measurement of the workpiece.

[0023] According to the first aspect, as Figures 2 - 4 described, in one embodiment, a scanning probe with a damping function is provided, which includes a connecting member 100, a probe needle 200, a detection component 300 and a damping member 700. The connecting member 100 is used to connect the probe needle 200 to the Z-axis 530 of the coordinate measuring machine. Specifically, the connecting member 100 can be connected to the Z-axis 530 through a locking mechanism 1111. The specific structure of the locking mechanism 1111 is the prior art and is similar to the structure of patent CN119148156. The detachable installation of the probe 400 and the Z-axis 530 is realized by rotating the lock.

[0024] The connecting member 100 may include a fixed part 110, a movable part 120 and a flexible part 130. The movable part 120 is movably connected to the fixed part 110 through the flexible part 130, and the probe needle 200 is connected to the movable part 120. The fixed part 110 can be understood as being fixed relative to the Z-axis 530, while the movable part 120 can be understood as being movable relative to the fixed part 110. Since the probe needle 200 is connected to the movable part 120, when the probe needle 200 contacts the workpiece, it will deflect, thereby driving the movable part 120 to move.

[0025] The form of the flexible part 130 can be various. For example, the flexible part 130 can be an elastic layer connected between the movable part 120 and the fixed part 110. The elastic layer can be made of a metal material with elasticity itself, or some gaps 135 can be processed on the elastic layer to further improve the flexibility of the elastic layer in any direction. In other embodiments, the elastic layer can also be a structure such as a spring or a spring piece that can undergo elastic deformation.

[0026] The detection component 300 includes a light source 310 and a position sensor 312. One of the light source 310 and the position sensor 312 is disposed on the fixed part 110, and the other is disposed on the movable part 120. The position sensor 312 can be a PSD (Position Sensitive Detector) optoelectronic position sensor. The measurement surface of the position sensor 312 can be perpendicular to the movable part 120 and face the light source 310 for receiving the light beam emitted by the light source 310. The position sensor 312 can be provided with one, two or more, and the central region of at least one position sensor 312 is located near the axis position of the fixed part 110. The position sensor 312 can also be electrically connected to an electronic device 1112, and the electronic device 1112 can include a multi-layer circuit board for processing the deflection signal of the position sensor.

[0027] The damping member 700 is disposed between the fixed part 110 and the movable part 120 for absorbing the vibration of the movable part 120 after the probe 200 leaves the workpiece. For the specific installation position of the damping member 700, it can be disposed on the fixed part 110, or on the movable part 120, or both the fixed part 110 and the movable part 120 are provided with the damping member 700 or a part of the damping member 700. The specific form of the damping member 700 can be a contact damping structure, such as a spring, a shrapnel or other structures that can absorb vibration through deformation. The damping member 700 can also be a structure with a magnetorheological fluid type. Or, the damping member 700 can also be a non-contact electromagnetic structure. Preferably, the damping member 700 is a structure with a magnetorheological fluid type.

[0028] When the probe 200 does not contact the workpiece, the flexible part 130 is used to drive the movable part 120 and the probe 200 to reset. When the probe 200 contacts the workpiece, the probe 200 drives the movable part 120 and the light source 310 or the position sensor 312 located on the movable part 120 to move. The central regions of the light source 310 and the position sensor 312 are deflected from each other, and the position sensor 312 generates a corresponding deflection signal according to the detected light deflection amount. Combining the deflection signal with the grating values of the X-axis 510 driving structure, the Y-axis 520 driving structure and the Z-axis 530 driving structure can be used to calculate the spatial coordinates of the contact point between the probe 200 and the workpiece. When the probe 200 contacts and then separates from the workpiece, the flexible part 130 can drive the movable part 120 and the probe 200 to reset. During the reset process, the probe 200 and the movable part 120 may vibrate continuously, and the damping member 700 can absorb the vibration and reduce the reset time.

[0029] According to the scanning probe with damping function of the above embodiment, the movable part 120 is connected to the fixed part 110 through the flexible part 130. When the probe 200 contacts the workpiece, the movable part 120 can deflect. Since one of the position sensor 312 and the light source 310 is arranged on the movable part 120 and the other is arranged on the fixed part 110, when the movable part 120 deflects, the relative position of the light source 310 and the position sensor 312 will move. Furthermore, the position sensor 312 can generate a deflection signal, and then the deflection amount of the probe 200 can be obtained through the deflection signal to calculate the three-dimensional coordinates when the probe 200 contacts the workpiece. The damper 700 can provide damping for the movable part 120 after the movable part 120 leaves the workpiece to be measured, avoiding continuous vibration of the movable part 120.

[0030] For the above scanning probe with damping function, the deflection amount of the probe 200 after contacting the workpiece to be measured can be accurately measured. At the same time, the above scanning probe with damping function is different from the trigger probe 400 that identifies whether the probe 200 deflects by the on-off of the circuit caused by the movement of the contact point. Instead, it allows the probe 200 to deflect through the deformable flexible part 130, measures the deflection signal of the probe 200 through the position sensor 312, and then combines the grating value of the motion system 500 to calculate the spatial coordinates of the contact point, avoiding the problems of anisotropy of the probe 400 and short service life of the probe 400 caused by the electrical contact structure.

[0031] It should be understood that the above "scanning probe" does not limit the usage mode of the probe 400. First, because the scanning probe with damping function of the present invention can measure the deflection of the probe 200 in real time through the position sensor 312, the probe 200 can move along the surface of the workpiece and perform a scanning operation, so that each measurement point can be quickly measured. In addition, the scanning probe with damping function of the present invention can also be used for trigger measurement. Specifically, since the scanning probe can measure the deflection of the probe 200 in real time through the position sensor 312, the moment when the probe 200 contacts can also be identified. When it is recognized that the probe 200 of the scanning probe contacts the workpiece, the motion system 500 can be used to control the scanning probe to retract, and the grating values of the X-axis 510 drive structure, Y-axis 520 drive structure, and Z-axis 530 drive structure when the probe 200 contacts are recorded to calculate the spatial coordinates of the contact point.

[0032] In some embodiments, as Figures 2 - 6 shown, the movable part 120 can swing relative to the fixed part 110 and has a swing fulcrum. The connection position of 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.

[0033] When the touch probe 200 deflects upon contacting the workpiece, it takes the swing fulcrum as the center of deflection, thereby driving the deflection of the light source 310 or the position sensor 312 at the other end of the swing fulcrum. Since one of the light source 310 or the position sensor 312 is fixedly connected to the fixed part 110, the relative position of the light source 310 or the position sensor 312 changes when the touch probe 200 deflects, and the position sensor 312 can generate a deflection signal.

[0034] In some embodiments, as Figure 4 described, the flexible part 130 includes a first elastic layer 131 and a second elastic layer 132 that are axially spaced apart along the fixed part 110. The first elastic layer 131 allows the movable part 120 to move in the horizontal direction and the axial direction, and the second elastic layer 132 is connected at the swing fulcrum and allows the movable part 120 to move in the axial direction.

[0035] When the touch probe 200 contacts the workpiece and is subjected to a force in the axial direction, the movable part 120 can move in the axial direction. When the touch probe 200 is subjected to a force in the horizontal direction, the movable part 120 will deflect, and the center of deflection is located at the second elastic layer 132. When the touch probe 200 detaches from the workpiece, the flexible part 130 can provide a restoring force to reset the touch probe 200.

[0036] The damping member 700 is located between the first elastic layer 131 and the second elastic layer 132. During the reset process of the movable part 120, the damping member 700 can quickly absorb the vibration energy of the movable part 120 and reduce the reset time. At the same time, by arranging the damping member 700 between the first elastic layer 131 and the second elastic layer 132, the structure of the connecting member 100 is made more compact.

[0037] In other embodiments, the damping member 700 can also be arranged on the side of the first elastic layer 131 away from the second elastic layer 132, or on the side of the second elastic layer 132 away from the first elastic layer 131.

[0038] In some embodiments, as Figure 4 and Figure 5 shown, the damping member 700 includes a magnet 710 and a magnetorheological fluid 720. The magnetorheological fluid 720 is arranged between the movable part 120 and the fixed part 110, and the magnet 710 is used to apply a magnetic field to the magnetorheological fluid 720 to provide damping. Specifically, the magnet 710 can be arranged on the fixed part 110, and the magnetorheological fluid 720 is filled between the magnet 710 and the movable part 120. The magnetorheological fluid 720 can be adsorbed by the magnet 710, and at the same time, the magnetorheological fluid 720 contacts the movable part 120 to provide damping to the movable part 120.

[0039] In other embodiments, the magnet 710 can also be arranged on the movable part 120, and the magnetorheological fluid 720 is filled between the magnet 710 and the fixed part 110.

[0040] In some embodiments, as Figure 4 and Figure 5 shown, the damping member 700 includes a fixing bracket 730. The fixing bracket 730 includes a connecting portion and a receiving portion 731. The connecting portion is fixedly connected to the fixing portion 110. The receiving portion 731 is used to receive the magnet 710. The fixing bracket 730 can be made of a metallic material, such as a soft magnetic material that can be magnetized, like iron, steel, etc. The receiving portion 731 has an annular receiving groove 7311. The opening of the receiving groove 7311 faces the movable portion 120. The magnet 710 is located in the receiving groove 7311. The two groove walls of the receiving groove 7311 respectively form a first pole shoe 7312 and a second pole shoe 7313.

[0041] After the magnet 710 is embedded in the receiving groove 7311, it can improve the magnetic field distribution and prevent the magnetorheological fluid 720 from flowing out of the gap between the magnet 710 and the movable portion 120. "Flowing out" means that the magnetorheological fluid 720 detaches from the magnet 710 or flows to the outer surface of the receiving portion 731 due to factors such as gravity or vibration. In other words, the receiving portion 731 can act as a pole shoe to improve the magnetic field distribution, keep the magnetorheological fluid 720 between the first pole shoe 7312 and the second pole shoe 7313, and prevent the magnetorheological fluid 720 from flowing away or diffusing to other positions due to gravity, thereby improving the long-term stability.

[0042] In addition, the setting of the receiving portion 731 can also prevent the leakage of the magnetic field. After testing, almost no magnetic field can be detected outside the receiving portion 731. Therefore, it can reduce the influence of the magnetic field on other devices.

[0043] In some embodiments, as Figure 4 and Figure 5 shown, the first pole shoe 7312 is disposed 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 portion 120 is greater than the radial distance between the second pole shoe 7313 and the movable portion 120.

[0044] Since when the movable portion 120 deflects, the deflection center 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 of the movable portion 120 at the second pole shoe 7313. The above-mentioned difference in the radial distance between the pole shoe and the movable portion 120 does not hinder the deflection of the probe 200. In addition, since the second pole shoe 7313 is located below the first pole shoe 7312 and the radial distance between the second pole shoe 7313 and the movable portion 120 is smaller, the magnetorheological fluid 720 is not easily drained due to gravity.

[0045] In some embodiments, the radial distance between the magnet 710 and the movable portion 120 is not greater than 5 millimeters. Setting the distance between the magnet 710 and the movable portion 120 to be smaller can use less magnetorheological fluid 720 and also reduce the risk of the magnetorheological fluid 720 flowing out.

[0046] The magnet 710 is a permanent magnet or an electromagnet. The electromagnet can control the intensity of damping through current, while the permanent magnet 710 can reduce the electrical components of the second module 112. Even the entire second module 112 can be made passive, which can not only reduce costs, but also reduce the influence of the circuit on the second module 112 and improve the service life of the second module 112. Preferably, the magnet 710 is a permanent magnet.

[0047] 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 only then can the scanning probe work properly.

[0048] The purpose of the above setting is to match the stylus 200 of different lengths. Specifically, during the measurement, a constant measuring force is maintained between the stylus 200 and the workpiece surface to ensure the same measurement conditions. However, the longer the stylus 200, the larger the moment arm, resulting in the same measuring force. After the longer stylus 200 deflects, the position change of the light source 310 at the upper end of the movable part 120 is smaller, that is, the position change of the light spot on the position sensor 312 is smaller, resulting in a decrease in resolution and affecting the measurement accuracy. Theoretically, 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 the higher the measurement accuracy.

[0049] For example, after the short stylus deflects, the light spot position moves 10 pixels, while after the stylus 200 deflects with the same measuring force, the light spot position only moves 5 pixels, and the resolution is reduced to one-half. Therefore, the longer the stylus 200, the greater the distance between the second elastic layer 132 in the fixed part 110 and the position sensor of the first module 111 needs to be. Therefore, it is necessary to adjust the distance between the swing fulcrum and the position sensor 312 according to different styli 200.

[0050] In some embodiments, such as Figure 9As shown, the fixing part 110 includes a first module 111 and a second module 112 connected axially. The probe 200 is connected to the second module 112 and is located at one end away from the first module 111. The position sensor 312 is fixed inside the first module 111, and the light source 310 is located inside the second module 112 and is fixedly connected to the movable part 120. The movable part 120 can be a probe holder for fixing the probe 200. The first module 111 is used to connect to the Z-axis 530, and the locking mechanism 1111 can be arranged in the first module 111. The first module 111 may further include electronic devices 1112, which can be located above the position sensor 312 and are used to process the deflection signal of the position sensor 312. In other embodiments, the light source 310 is fixed inside the first module 111, and the position sensor 312 is fixedly connected to the movable part 120.

[0051] The second module 112 includes an inner shell 1121 and an outer shell 1122. The movable part 120 is connected to the inner shell 1121 through a flexible part 130, and the position of the inner shell 1121 relative to the outer shell 1122 in the axial direction is adjustable. Specifically, the inner shell 1121 and the outer shell 1122 can be cylindrical, and the outer shell 1122 is sleeved on the outer peripheral side of the inner shell 1121. At least two sliders 1123 are arranged at intervals along the outer peripheral direction of the inner shell 1121 between the inner shell 1121 and the outer shell 1122. The plurality of sliders 1123 can be evenly arranged at intervals along the outer peripheral direction of the inner shell 1121, which is beneficial to improving the coaxiality of the inner shell 1121 and the outer shell 1122.

[0052] An elastic pad is arranged between at least one slider 1123 and the inner shell 1121 or the outer shell 1122. The purpose of arranging the elastic pad is to pre-tighten the slider 1123 between the inner shell 1121 and the outer shell 1122, thereby realizing the gapless connection between the inner shell 1121 and the outer shell 1122. Specifically, an elastic pad can be laid on a part of the outer peripheral surface of the inner shell 1121, and then the sliding block is fixed on the elastic pad to achieve the pre-tightening effect.

[0053] The thickness of at least one slider 1123 in the radial direction is adjustable so that the inner shell 1121 and the outer shell 1122 are kept coaxial. Specifically, the slider 1123 can be threadedly connected to the inner shell 1121 or the outer shell 1122 in the radial direction to adjust the thickness of the slider 1123 protruding from the inner shell 1121 or the outer shell 1122, that is, the above-mentioned radial thickness, by rotating the slider 1123. When the inner shell 1121 and the outer shell 1122 are deviated from coaxiality, the coaxiality can be adjusted by rotating the slider 1123. In other embodiments, multiple sliders 1123 with different thicknesses can also be prepared in advance and then sequentially installed between the inner shell 1121 and the outer shell 1122 to realize the adjustment of the coaxiality of the inner shell 1121 and the outer shell 1122.

[0054] In some embodiments, guiding grooves extending in the axial direction may also be provided on the inner wall of the outer shell body 1122, and guiding protrusions extending in the axial direction may be provided on the inner shell 1121 to prevent rotation between the inner shell 1121 and the outer shell body 1122. For the above embodiments having sliding blocks, guiding grooves extending in the axial direction may be provided only on the inner wall of the outer shell body 1122. At this time, the slider 1123 fixedly connected to the inner shell 1121 simultaneously functions as the above-mentioned guiding protrusion.

[0055] In some embodiments, as Figure 9 shown, a plurality of circumferentially extending card slots 1124 may also be provided on the outer wall of the inner shell 1121. The plurality of card slots 1124 are arranged at intervals in the axial direction, and different card slots 1124 are matched with probe needles 200 of different lengths. The outer shell 1122 may also be provided with at least one radially movable latch 1125. The latch 1125 can be inserted into the card slot 1124 to limit the position of the inner shell 1121 in the axial direction, thereby limiting 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 latches 1125 may also be provided, and the plurality of latches 1125 may be evenly spaced along the outer circumference of the outer shell 1122, thereby improving the force uniformity of the flexible portion 130 in any direction.

[0056] In a specific embodiment, the card slot 1124 may include a first card slot and a second card slot axially spaced from the first card slot, and the second card slot is located below the first card slot. When using a short probe needle, the first card slot is moved near the latch 1125 and the latch 1125 is inserted. When replacing the long probe needle, the latch 1125 is loosened, the second card slot is moved near the latch 1125 and the latch 1125 is inserted. The positions between the first card slot and the second card slot can be calculated based on the spot displacement caused by different probe needles under the same measuring force, the size of the probe needle, and the size of the movable portion 120.

[0057] The specific form of the latch 1125 may be a setscrew or an elastic ball plunger, etc. The latch 1125 of the above form is threadedly connected to the outer shell 1122. In other embodiments, the latch 1125 may also be a positioning block, and the positioning block can be inserted into the card slot 1124 in the radial direction. At this time, the latch 1125 is plug-connected to the outer shell 1122.

[0058] In some embodiments, as Figure 9 shown, an elastic member 1126, such as a spring, may also be provided between the top of the inner shell 1121 and the second module 112, so that the inner shell 1121 has a tendency to move axially, thereby eliminating the axial clearance.

[0059] In some embodiments, at least two light sources 310 are provided at the upper end of the movable part 120. A diaphragm 313 is provided in the light-emitting direction of the light sources 310. The light sources 310 and the diaphragm 313 remain relatively stationary. After passing through the diaphragm 313, the light beams emitted by different light sources 310 have different propagation directions and reach the position sensor to form multiple light spots. When the movable part 120 deflects, due to the change in the position of the light sources 310, the positions of the light spots on the position sensor also change, and there is a one-to-one correspondence between the position change of the light spots and the deflection of the probe 200. Therefore, the deflection of the probe 200 can be calculated based on the information of the position sensor 312, that is, the contact position between the probe 200 and the workpiece surface can be calculated.

[0060] The detection component 300 may further include focusing elements such as a focusing lens and a concave mirror, so that the focusing position of the light beam can be near the position sensor 312, thereby reducing the size of the light spot. Since the smaller the light spot, the more accurate the position sensor can identify the position of the light spot, the measurement accuracy can be improved. For the focusing lens, it can be provided between the diaphragm 313 and the position sensor 312. For the concave mirror, the light source 310 can be fixed on the first module 111 and reflected to the position sensor 312 through the concave mirror located in the second module 112. The concave mirror is fixedly connected to the movable part 120.

[0061] In some embodiments, as Figure 2 shown, the first module 111 and the second module 112 are detachably connected. One end of the first module 111 connected to the second module 112 is the first connection end. One end of the second module 112 connected to the first module 111 is the second connection end.

[0062] Light-transmitting materials, such as glass 1113, can be provided in the middle regions of the first connection end and the second connection end. Therefore, the light beam can pass through the light-transmitting material to reach the position sensor, and at the same time, it is beneficial to prevent dust from entering the first module 111 and affecting the measurement. In other embodiments, through holes can also be provided in the middle regions so that the light beam can directly pass through.

[0063] Magnetic materials 1129, such as neodymium iron boron magnets 710, can be provided around the middle regions of the first connection end or the second connection end for realizing the adsorption between the first module 111 and the second module 112. The magnetic adsorption material can continuously surround the middle region or be composed of multiple spaced segments.

[0064] Positioning pins and adapted positioning grooves can also be provided at the first connection end and the second connection end for the preliminary positioning of the first module 111 and the second module 112 before installation. Specifically, one of the first module 111 and the second module 112 is provided with a positioning pin, and the other is provided with a positioning groove adapted to the outer shape of the positioning pin.

[0065] The first connection end and the second connection end may also be provided with at least two positioning balls 1114 and matching positioning V-grooves 1127 for positioning when the first module 111 and the second module 112 are installed. That is, one of the first module 111 and the second module 112 is provided with positioning balls 1114, and the other is provided with positioning V-grooves 1127 that are shaped to match the positioning balls 1114. Preferably, three positioning balls 1114 are provided, and the three positioning balls 1114 are evenly spaced, with an angular interval of 120 degrees between adjacent ones.

[0066] The first connection end and the second connection end may also be provided with electrical contacts 1115 and conductive sheets 1128 for realizing the electrical connection between the first module 111 and the second module 112, or for determining whether the second module 112 has been installed on the first module 111. Specifically, in the first module 111 and the second module 112, one is provided with electrical contacts 1115, and the other is provided with a conductive sheet 1128 for contacting the electrical contacts 1115.

[0067] If it is used to determine whether the second module 112 has been installed on the first module 111, two electrical contacts 1115 may be provided. When the first module 111 and the second module 112 are connected, the two electrical contacts 1115 of the first module 111 contact the conductive sheet 1128 of the second module 112 to form a closed circuit. Therefore, it is possible to determine whether the second module 112 has been installed on the first module 111 according to whether the circuit is closed. In some embodiments, different probe needles 200 need to be equipped with different second modules 112. At this time, different second modules 112 may have different arrangements of electrical contacts 1115. Therefore, the first module 111 can determine the type of the currently connected second module 112 according to the conducting contacts.

[0068] In some embodiments, the second module 112 and the probe needle 200 are detachably connected. Since the positioning connection method between the second module 112 and the probe needle 200 is the same as the connection method between the first module 111 and the second module 112 described above, it will not be elaborated here.

[0069] In some embodiments, as Figure 4 shown, the first elastic layer 131 is arranged closer to the light source 310 or the position sensor 312 than the second elastic layer 132. Since the swing fulcrum is located on the second elastic layer 132, the above arrangement makes the distance between the swing fulcrum and the light source 310 or the position sensor 312 farther. When the probe needle 200 deflects, the displacement of the light source 310 or the position sensor 312 fixed to the upper end of the movable part 120 is greater, that is, the relative displacement between the light source 310 and the position sensor 312 is greater, which is beneficial to improving the measurement accuracy.

[0070] In other embodiments, the second elastic layer 132 is disposed closer to the light source 310 or the position sensor 312 than the first elastic layer 131. Since the swing fulcrum is located on the second elastic layer 132, the above arrangement makes the distance between the swing fulcrum and the end of the stylus 200 farther. When the stylus 200 contacts the workpiece and receives a severe collision, due to the longer force arm of the measuring force, and the first elastic layer 131 has better flexibility in the horizontal direction compared with the second elastic layer 132, it can play a better buffering role and reduce the risk of deformation of the stylus 200 and the movable part 120.

[0071] In some embodiments, such as Figure 4 、 Figure 7 and Figure 8 shown, both the first elastic layer 131 and the second elastic layer 132 have an outer peripheral region 134, a central region 133 located within the outer peripheral region 134, and an elastic region located between the outer peripheral region 134 and the central region 133. The outer peripheral region 134 is connected to the fixing part 110, and the central region 133 is connected to the movable part 120.

[0072] The connection between the central region 133 of the elastic layer and the movable part 120 can be by means of fasteners such as screws, or by gluing, welding, etc. Correspondingly, the connection between the outer peripheral region 134 of the elastic layer and the fixing part 110 can be by means of fasteners such as screws, or by gluing, welding, etc.

[0073] In some embodiments, such as Figure 4 、 Figure 7 and Figure 8 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.

[0074] Under the condition that the first elastic layer 131 and the second elastic layer 132 are of the same size, since the first elastic layer 131 has a smaller central region 133, a larger elastic region can be left, so that the flexibility of the first elastic layer 131 in the horizontal direction and the axial direction is better. The larger central region 133 of the second elastic layer 132 can strengthen its rigidity in the horizontal direction, and the flexibility in the axial direction can be achieved by providing a longer circumferentially extending gap 135 in its elastic region.

[0075] It should be noted that the second elastic layer 132 is not only flexible in the axial direction, but also can have a certain degree of flexibility in the horizontal direction, but compared with the first elastic layer 131, the flexibility of the second elastic layer 132 in the horizontal direction is smaller.

[0076] In some embodiments, such as Figure 4, Figure 7 and Figure 8 As shown in Figure 7 and Figure 8 , gaps 135 are provided in the elastic regions of the first elastic layer 131 and the second elastic layer 132, and the gaps 135 extend from the central region 133 to the peripheral region 134. Specifically, the extending shape of the gaps 135 can be spiral, and gradually extend from the central region 133 to the peripheral region 134. The gaps 135 can be continuous or discontinuous, as long as they extend from the central region 133 to the peripheral region 134 as a whole. The number of the gaps 135 can be one or multiple.

[0077] In the direction from the central region 133 to the peripheral region 134, the number of the gaps 135 on the first elastic layer 131 is greater than that on the second elastic layer 132, and / or the width of the gaps 135 on the first elastic layer 131 is greater than that on the second elastic layer 132. It can be understood that when the circumferentially extending gaps 135 are formed in the elastic region, the more the number of the circumferentially extending gaps 135 or the greater the width of the gaps 135 in a specific direction in the horizontal direction, the easier the movable part 120 is to move in this specific direction, that is, it has better flexibility in this direction. Considering from another angle, in the direction from the central region 133 to the peripheral region 134, the more the part removed from the elastic region, the better the flexibility.

[0078] For example Figure 7 In the direction a shown in Figure 7 , it can be considered that there are five gaps 135 from the central region 133 to the peripheral region 134, and these five gaps 135 make the central region 133 of the first elastic layer 131 easy to move relative to the peripheral region 134 in the direction a. Similarly, the gaps 135 shown in the figure make the central region 133 of the first elastic layer 131 easy to move relative to the peripheral region 134 in any horizontal direction.

[0079] It can be further understood that when the circumferentially extending gaps 135 of the first elastic layer 131 are more in number or greater in width than those of the second elastic layer 132, the first elastic layer 131 has greater flexibility in the horizontal direction and can allow the movable part 120 to move in the horizontal direction. Secondly, the part of the elastic region except the gaps 135 can be defined as a connecting part. The longer the length of the circumferentially extending gaps 135, or the smaller the area of the connecting part near the circumferentially extending gaps 135, the easier the movable part 120 is to move in the axial direction.

[0080] The gaps 135 of the first elastic layer 131 can extend from the central region 133 to the peripheral region 134. Thus, the multiple gaps 135 can allow the central region 133 to move axially relative to the peripheral region 134 while allowing the movable part 120 of 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. Thus, the multiple gaps 135 can allow the central region 133 to move axially relative to the peripheral region 134 while allowing the movable part 120 of the central region 133 to tilt. However, due to the different settings of the above-mentioned gaps 135, the movable part 120 has less flexibility and lower degrees of freedom in the horizontal direction of the second elastic layer 132, making the deflection center of the movable part 120 stay near the second elastic layer 132.

[0081] In some embodiments, at least two gaps 135 are provided in the elastic region of the first elastic layer 131, and the at least two gaps 135 are arranged in central symmetry so that the deflection resistance of the movable part 120 is the same in any horizontal direction. It can be understood that since the two gaps 135 are arranged in central symmetry, the number and width of the gaps 135 can be made as consistent as possible in any specific direction in the horizontal plane, thereby making the deflection resistance of the movable part 120 more consistent in any specific direction.

[0082] As Figure 4 and Figure 7 shown, the extension trajectory of the gap 135 can be an Archimedean spiral. When the number of gaps 135 is two, the two gaps 135 can be arranged in central symmetry, that is, among the two gaps 135, one gap 135 extends clockwise and the other extends counterclockwise.

[0083] In addition, the proportionality 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 in different directions of the first elastic layer 131. 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, so as to improve the measurement accuracy. On the contrary, since mechanical structures such as the stylus 200 and the movable part 120 will deform after being stressed, when measuring the same point of the workpiece, if the measuring force is different when contacting the workpiece in different directions, it may cause the stylus 200 to have different bending degrees, which is not conducive to improving the measurement accuracy, and this is also one of the inevitable defects of the trigger probe 400.

[0084] In some embodiments, as Figure 8As shown, the gap 135 on the second elastic layer 132 is provided with an adjustable area 1321, and the width of the gap 135 in the adjustable area 1321 is adjustable to adjust the elastic coefficient 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, in the second elastic layer 132, the shape of the gap 135 can be adjusted. Specifically, the larger the width of the gap 135 in the adjustable area 1321, the smaller the elastic coefficient of the second elastic layer 132 in the axial direction, that is, the better the flexibility; the smaller the width of the gap 135 in the adjustable area 1321, the larger the elastic coefficient of the second elastic layer 132 in the axial direction, that is, the worse the flexibility. Specifically, the width of the gap 135 in the adjustable area 1321 can be adjusted according to the actual situation.

[0085] It can be understood that the number of 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.

[0086] According to a second aspect, in an embodiment, a coordinate measuring machine is provided, which is characterized in that it includes a carrier 600, a driving mechanism, and the scanning probe with damping function according to any one of the above embodiments. The carrier 600 is used to carry the workpiece to be measured; the scanning probe is located above the carrier 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.

[0087] The above uses specific examples to elaborate on the present invention, which is only used to help understand the present invention and is not intended to limit the present invention. For those skilled in the technical field to which the present invention belongs, based on the idea of the present invention, several simple deductions, deformations or substitutions can also be made.

Claims

1. A scanning probe with damping function, characterized in that, Comprising: A connecting member, including a fixed portion, a movable portion and a flexible portion, wherein the movable portion is movably connected to the fixed portion through the flexible portion; A probe, connected to the movable portion; A detection assembly, including 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, disposed on the fixed portion and / or the movable portion, for absorbing the vibration of the movable portion after the probe leaves the workpiece; Wherein, when the probe does not contact the workpiece, the flexible portion is used to drive the movable portion and the probe to reset; when the probe contacts the workpiece, the probe drives the movable portion and the light source or the position sensor located on the movable portion to move, the light source and the position sensor deflect relative to each other, and the position sensor generates a corresponding deflection signal according to the detected light deflection amount, and the deflection signal is used to calculate the spatial coordinates of the contact point between the probe and the workpiece.

2. The scanning probe with damping function according to claim 1, characterized in that, The movable portion is capable of swinging relative to the fixed portion and has a swing fulcrum, the connection position of the probe 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.

3. The scanning probe with damping function according to claim 2, wherein, The flexible portion includes a first elastic layer and a second elastic layer arranged at intervals along the axial direction of the fixed portion. The first elastic layer allows the movable portion to move in the horizontal direction and the axial direction, 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.

4. The scanning probe with damping function according to claim 3, characterized in that, The damping member includes a magnet and a magnetorheological fluid. The magnetorheological fluid 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 magnetorheological fluid to provide damping.

5. The scanning probe with damping function according to claim 4, characterized in that, The damping member includes a fixing bracket, the fixing bracket includes a connecting portion and a receiving portion, the connecting portion is fixedly connected to the fixed portion, and the receiving portion is used to receive the magnet.

6. The scanning probe with damping function according to claim 5, characterized in that, The fixing bracket is made of a soft magnetic material. The receiving portion has an annular receiving groove, the opening of the receiving groove faces the movable portion, the magnet is located in the receiving groove, and the two groove walls of the receiving groove respectively form a first pole shoe and a second pole shoe.

7. The scanning probe with damping function according to claim 6, wherein, The first pole shoe is disposed closer to the first elastic layer than the second pole shoe, and the radial distance between the first pole shoe and the movable portion is greater than the radial distance between the second pole shoe and the movable portion.

8. The scanning probe with damping function according to claim 4, characterized in that, The radial distance between the magnet and the movable portion is not greater than 5 millimeters.

9. The scanning probe with damping function according to claim 4, characterized in that, The magnet is a permanent magnet or an electromagnet.

10. A three - coordinate measuring machine, characterized in that, Comprising a carrying table, a driving mechanism and a scanning probe with a damping function according to any one of claims 1-9. The carrying table is used to carry the workpiece to be measured; the scanning probe is located above the carrying table, and the driving mechanism is used to drive the scanning probe to move in the X-axis direction, Y-axis direction and Z-axis direction.

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