Contour measuring instrument

Abstract

The invention discloses a contour measuring instrument, and belongs to the technical field of contour measuring instruments. Through a switching mechanism and a guiding mechanism, when a measured object needs to be measured, the measured object is obliquely fixed by using a clamp, then a contact pin mounting cavity is rotated to select a sensor contact pin matched with the measured object, and then the measured object is measured; when the contact pin installation cavity drives the sliding block and the sensor contact pin to rotate, the sliding block drives the ball to roll in the guide groove through the installation frame, the sliding block can ascend and descend in the contact pin installation cavity along the track of the guide groove along with abutting of the ball and the guide groove, and when the ball moves to the lowest position of the guide groove, the sliding block drives the sensor contact pin to move out of the contact pin installation cavity. And the adaptive sensor contact pins are prepared, and the rest sensor contact pins are accommodated in the mounting cavity.

Description

Technical Field

[0001] The present invention relates to the technical field of contour measuring instruments, and in particular to a contour measuring instrument. Background Art

[0002] A profilometer is a precision device used to measure the contours of an object. An electric profilometer uses a contact-type measurement method where the instrument's stylus slides against the surface being measured. The sensor (with a built-in stylus) is placed on the surface of the workpiece being measured, and the driver drives the sensor to slide at a constant speed along the surface. The sensor senses changes in the geometric shape of the surface being measured through the built-in stylus. These changes cause the stylus to move up and down, and the sensor generates an analog signal proportional to the contour of the surface being measured. This analog signal is amplified and level-converted, then converted into a digital signal that enters the data acquisition system. The computer analyzes and calculates the collected raw contour data to derive the shape and size information of the surface being measured. Depending on the shape and size of the object to be measured, styluses of different diameters need to be selected. In practical applications, for the measurement of fine surface contours, it is advisable to use a stylus with a smaller diameter. A stylus with a smaller diameter can more sensitively capture subtle changes in the measured surface, thereby improving measurement accuracy. For rough or uneven surfaces, a stylus with a larger diameter can be selected. A stylus with a larger diameter can better maintain contact with the measured surface to enhance measurement stability and durability. Existing profilometers still use the traditional method of replacing styluses. A screwdriver is used to remove the probe from the main unit, and then the stylus part is unscrewed and removed. After installing the new stylus, it is tightened and fixed. The operation is relatively cumbersome. In addition, the diameter of the electric profilometer stylus is usually between 0.1mm and 5mm. It is a very precise component. Even slight damage to it may affect the measurement accuracy. The manual disassembly and installation method is prone to bending, breaking or wear of the stylus during contact. Summary of the Invention

[0003] The purpose of the present invention is to propose a contour measuring instrument to solve the problem that manual replacement of the stylus is cumbersome and easily causes the stylus to bend, break or wear during contact, which may affect the accuracy of measurement.

[0004] In order to achieve the above purpose, the present invention adopts the following technology: a contour measuring instrument: The profilometer comprises a test bench, a liftable driver mounted on the test bench, a sensor disposed at the end of the driver, and a plurality of sensor styluses of different diameters mounted on the sensor. The test bench is provided with a fixture located below the sensor stylus, on which a measured object is fixed. The sensor is provided with a switching mechanism, the switching mechanism comprising an annular sensitive element disposed on the sensor and a plurality of stylus mounting cavities disposed below the annular sensitive element. The stylus mounting cavity rotates about the sensor and has a liftable slider disposed therein. The sensor stylus is slidably mounted on the slider and abuts against the measured object as the slider descends. The sensor stylus moves up and down within the slider according to the surface contour of the measured object. The sensor is also provided with a guiding mechanism, which includes an abutment ring arranged in the middle of the sensor and a guide groove opened on the surface of the abutment ring. The slider drives the sensor stylus to rise and fall while also being able to rotate along the track of the guide groove. The sensor stylus that matches the object to be measured rotates to the top of the fixture and extends out from the stylus mounting cavity, and the remaining sensor stylus pins are received in the stylus mounting cavity.

[0005] As a further description of a profilometer for the above technology: The switching mechanism also includes a plug arranged at the top of the stylus mounting cavity and a spiral cable arranged on the sensor stylus. The sensor stylus is connected to the plug through the spiral cable and both plugs are inserted into the annular sensitive element. When the sensor stylus descends, the spiral cable is pulled to extend and stretch. When the sensor stylus rises, the spiral cable rebounds and resets.

[0006] As a further description of a profilometer for the above technology: The guiding mechanism further comprises a mounting frame mounted on the sliding block, wherein balls are embedded in the mounting frame and are all embedded in the guide grooves and move along the guide grooves.

[0007] As a further description of a profilometer for the above technology: The switching mechanism also includes two first guide rods arranged inside the stylus mounting cavity. The first guide rods penetrate the surface of the slider and are wound with a first spring on the portion of the surface above the slider. One end of the first spring is connected to the slider and the other end is connected to the top of the inner wall of the stylus mounting cavity. The first spring pulls the ball to abut against the guide groove through the rebound force.

[0008] As a further description of a profilometer for the above technology: The stylus mounting cavity is connected to the abutment ring via a rotating mechanism, which includes a rotating rod that passes through the middle of the sensor and is rotatably arranged, and a liftable mounting ring that is mounted at the bottom of the rotating rod, and a rotating knob is provided at the top of the rotating rod; A number of card blocks are equidistantly arranged around the mounting ring, and a card groove that cooperates with the card block is installed at the bottom of the stylus mounting cavity. When the mounting ring descends, the stylus mounting cavity drives the plug to be pulled out of the annular sensitive element, and the rotating rod is rotated to cause the mounting ring to drive multiple stylus mounting cavities to rotate.

[0009] As a further description of a profilometer for the above technology: An unlocking mechanism is provided between the rotating rod and the mounting ring, the unlocking mechanism comprising a connecting rod mounted in the middle of the mounting ring and a push rod passing through the middle of the rotating rod, the connecting rod being movably embedded in the rotating rod and the top of the connecting rod abutting against the push rod; The top of the push rod is provided with a threaded rod, and the interior of the rotating rod is provided with a threaded groove that meshes with the threaded rod. The threaded rod is rotated to make the push rod descend in the rotating rod and push the mounting ring.

[0010] As a further description of a profilometer for the above technology: A countersunk hole is provided on the top of the knob, the threaded rod is located in the countersunk hole, and the distance from the top to the bottom of the countersunk hole is the same as the movable distance of the threaded rod.

[0011] As a further description of a profilometer for the above technology: An annular groove is provided on the inner wall of the rotating rod, and a plurality of second guide rods are arranged in the groove. A fitting ring is mounted on the surface of the connecting rod, and a through hole for the second guide rod to pass through is provided on the surface of the fitting ring. A second spring is wound around the surface of the second guide rod below the fitting ring, and the two ends of the second spring are respectively connected to the fitting ring and the bottom of the annular groove.

[0012] As a further description of a profilometer for the above technology: The sensor is provided with a one-way mechanism for limiting the rotation direction of the rotating rod. The one-way mechanism includes a rotating cavity opened on the sensor and a gear ring sleeved on the surface of the rotating rod. The gear ring is rotatably embedded in the rotating cavity, and the inner wall of the rotating cavity is provided with a plurality of connectors that engage with the gear ring. The connectors limit the gear ring so that it can only rotate in one direction.

[0013] As a further description of a profilometer for the above technology: The connector includes a hinged shaft arranged on the inner wall of the rotating chamber, a hook is rotatably arranged on the hinged shaft, and the teeth of the hook and the gear ring are both provided with a flat surface and an inclined surface. When the flat surface of the teeth of the gear ring abuts the flat surface of the hook, the rotating rod cannot rotate; A torsion spring is wound around the hinge shaft, and two ends of the torsion spring are respectively connected to the hook and the hinge shaft.

[0014] In summary, due to the use of the above-mentioned technology, the beneficial effects of the present invention are: 1. Through the provided switching mechanism and guiding mechanism, when it is necessary to measure the object to be measured, the clamp is used to fix the object to be measured in an inclined position, and then the stylus mounting cavity is rotated to select the sensor stylus that is suitable for the object to be measured. When the stylus mounting cavity drives the slider and the sensor stylus to rotate, the slider drives the ball to roll in the guide groove through the mounting frame. As the ball contacts the guide groove, the slider can rise and fall along the track of the guide groove in the stylus mounting cavity. When the ball moves to the lowest point of the guide groove, the slider drives the sensor stylus to move out of the stylus mounting cavity, and the adapted sensor stylus is ready. At the same time, the remaining sensor stylus is stored in the stylus mounting cavity. 2. Through the provided rotation mechanism and unlocking mechanism, the connecting rod is pushed by the push rod, drives the engaging ring to descend under the restriction of the second guide rod and squeezes the second spring to cause it to undergo elastic deformation until the mounting ring drives the plug to separate from the annular sensitive element to release the restriction on the stylus mounting cavity, and the stylus mounting cavity drives the plug to descend and disengage from the annular sensitive element. At this time, by rotating the knob, the knob drives the clamping block to rotate through the mounting ring, and the clamping block drives the stylus mounting cavity to rotate through the clamping slot, thereby achieving the purpose of driving multiple stylus mounting cavities to rotate simultaneously. The sensor stylus in the stylus mounting cavity that rotates toward the top of the fixture and the object to be measured will move out with the rotation, while the sensor stylus that rotates to other positions will be retracted into the stylus mounting cavity for protection, thereby achieving the purpose of contactless and rapid switching. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the three-dimensional structure of a profilometer is shown; Figure 2 A schematic diagram of a partial three-dimensional structure of a sensor, a fixture, and a sensor stylus is shown; Figure 3 shows a schematic diagram of a three-dimensional cross-sectional structure of a sensor; Figure 4 Shown Figure 3 Schematic diagram of the enlarged structure at A in the middle; Figure 5 shows a schematic diagram of the front cross-sectional structure of the sensor; Figure 6 Shown Figure 5 Schematic diagram of the enlarged structure at B in the middle; Figure 7 A schematic diagram of the partial three-dimensional structure of the switching mechanism and the guiding mechanism is shown; Figure 8 A schematic diagram of a partial three-dimensional structure of the sensor stylus being adjusted under the restriction of the guide mechanism is shown; Figure 9 A schematic diagram of the partial three-dimensional structure of the slider, the guide mechanism and the sensor stylus is shown; Figure 10 A schematic diagram of the three-dimensional structure of the abutment ring and the guide groove is shown; Figure 11 A schematic diagram of a partially disassembled state of the annular sensitive element and the plug is shown; Figure 12 A schematic diagram of the three-dimensional disassembled state of the rotating mechanism and the unlocking mechanism is shown; Figure 13 A schematic diagram of a top cross-sectional structure of a one-way mechanism is shown; Figure 14 A schematic diagram of the three-dimensional structure of the connector is shown.

[0016] Legend: 10. Contour measuring instrument body; 11. Test bench; 12. Driver; 13. Sensor; 14. Fixture; 15. Sensor stylus; 20. Switching mechanism; 21. Ring-shaped sensitive element; 22. Contact pin mounting cavity; 23. Slider; 24. First guide rod; 25. First spring; 26. Spiral cable; 27. Plug; 30. Guide mechanism; 31. Mounting frame; 32. Ball bearing; 33. Abutment ring; 34. Guide groove; 40. Rotation mechanism; 41. Rotating rod; 411. Second guide rod; 412. Second spring; 42. Mounting ring; 43. Block; 44. Rotating knob; 45. Slot; 50. Unlocking mechanism; 51. Connecting rod; 511. Engaging ring; 52. Push rod; 53. Threaded rod; 60. One-way mechanism; 61. Rotating chamber; 62. Gear ring; 63. Connector; 631. Articulated shaft; 632. Hook; 633. Torsion spring. DETAILED DESCRIPTION

[0017] The following provides a clear and complete description of a profilometer according to an embodiment of the present invention, in conjunction with the accompanying drawings. Obviously, the described embodiments represent only a portion of the present invention, not all of it. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are considered within the scope of protection of the present invention.

[0018] In order to solve the problem that the manual replacement of the stylus is cumbersome and easily causes the stylus to bend, break or wear during contact, which may affect the accuracy of measurement, the present invention proposes a contour measuring instrument, such as Figure 1 - Figure 14 As shown: The profilometer includes a body 10, which includes a test table 11, a driver 12 mounted on the test table 11 and capable of being raised and lowered, a sensor 13 disposed at the end of the driver 12, and a plurality of sensor styluses 15 of different diameters mounted on the sensor 13. A fixture 14 is mounted on the test table 11 and is located below the sensor stylus 15. The fixture 14 fixes the object to be measured. The sensor 13 is provided with a switching mechanism 20, such as Figure 3 As shown, the switching mechanism 20 includes an annular sensitive element 21 provided on the sensor 13 and a plurality of stylus mounting cavities 22 provided below the annular sensitive element 21. The stylus mounting cavity 22 rotates about the sensor 13 and has a liftable slider 23 provided therein. The sensor stylus 15 is slidably mounted on the slider 23 and abuts against the object being measured as the slider 23 descends. The sensor stylus 15 moves up and down within the slider 23 according to the surface contour of the object being measured. The sensor 13 is also provided with a guiding mechanism 30, such as Figures 8-10 As shown, the guide mechanism 30 includes an abutment ring 33 provided in the middle of the sensor 13 and a guide groove 34 provided on the surface of the abutment ring 33. The slider 23 drives the sensor stylus 15 up and down while also being able to rotate along the track of the guide groove 34. The guide mechanism 30 further includes a mounting frame 31 mounted on the slider 23. Balls 32 are rotatably embedded in the mounting frame 31. The balls 32 are all rotatably embedded in the guide grooves 34 and move along the tracks thereof. When the object to be measured needs to be measured, the fixture 14 is used to fix the object to be measured in an inclined state, and then the stylus installation cavity 22 is rotated to select the sensor stylus 15 adapted to the object to be measured. When the stylus installation cavity 22 drives the slider 23 and the sensor stylus 15 to rotate, as shown in FIG. Figure 8 As shown, the slider 23 drives the ball 32 to roll in the guide groove 34 through the mounting bracket 31. As the ball 32 abuts the guide groove 34, the slider 23 can rise and fall along the track of the guide groove 34 in the stylus mounting cavity 22. When the ball 32 moves to the lowest point of the guide groove 34, the slider 23 drives the sensor stylus 15 to move out of the stylus mounting cavity 22. The adapted sensor stylus 15 is ready, and the remaining sensor stylus 15 is stored in the stylus mounting cavity 22. like Figure 9 As shown, the switching mechanism 20 also includes a plug 27 provided at the top of the stylus mounting cavity 22 and a spiral cable 26 provided on the sensor stylus 15. The sensor stylus 15 is connected to the plug 27 via the spiral cable 26, and the plug 27 is inserted into the annular sensitive element 21. When the sensor stylus 15 descends, the spiral cable 26 is pulled to extend. When the sensor stylus 15 ascends, the spiral cable 26 rebounds and resets. As the sensor stylus 15 is connected to the annular sensitive element 21 via the spiral cable 26 and the plug 27, the sensor 13 is ready. At this time, the driver 12 is started again, so that the driver 12 drives the sensor 13 to descend until the sensor stylus 15 contacts the object to be measured. The driver 12 is then started again to drive the sensor 13 to slide at a constant speed along the surface of the object to be measured. The sensor stylus 15 senses the geometric shape changes of the surface of the object to be measured, and the sensor stylus 15 moves up and down under the restriction of the slider 23. The contour data signal is transmitted to the sensor 13 through the spiral cable 26 and the plug 27. The computer analyzes and calculates the collected data to obtain the shape and size information of the surface of the object to be measured, and the detection operation is completed.

[0019] Furthermore, in order to enable the ball 32 to maintain contact with the guide groove 34 and avoid dislocation, the switching mechanism 20 also includes two first guide rods 24 arranged inside the stylus mounting cavity 22. The first guide rods 24 pass through the surface of the slider 23 and a first spring 25 is wound around the portion of the surface above the slider 23. One end of the first spring 25 is connected to the slider 23, and the other end is connected to the top of the inner wall of the stylus mounting cavity 22, so that the first spring 25 pulls the ball 32 into contact with the guide groove 34 through the rebound force.

[0020] When the sensor stylus 15 needs to be switched, the plug 27 needs to be pulled out from the annular sensitive element 21 first, and then the stylus mounting cavity 22 needs to be rotated. Under the guidance of the guide groove 34, the currently extended sensor stylus 15 needs to be put into the stylus mounting cavity 22. At the same time, the sensor stylus 15 matching the object to be measured needs to be rotated to the top of the fixture 14 and extended from the stylus mounting cavity 22. In order to achieve this operation, Figure 4-Figure 5 、 Figure 7-Figure 8 As shown, the stylus mounting cavity 22 is connected to the abutment ring 33 via a rotating mechanism 40. The rotating mechanism 40 includes a rotating rod 41 that passes through the middle of the sensor 13 and is rotatably arranged, and a liftable mounting ring 42 that is mounted at the bottom of the rotating rod 41. A rotating knob 44 is provided at the top of the rotating rod 41. A plurality of locking blocks 43 are equidistantly arranged around the mounting ring 42. A locking groove 45 is installed at the bottom of the stylus mounting cavity 22 to cooperate with the locking blocks 43. When the mounting ring 42 is lowered, the stylus mounting cavity 22 drives the plug 27 to be withdrawn from the annular sensitive element 21. Rotating the rotating rod 41 causes the mounting ring 42 to drive the multiple stylus mounting cavities 22 to rotate. When it is necessary to switch the sensor stylus 15, the mounting ring 42 is lowered. At this time, the mounting ring 42 drives the stylus mounting cavity 22 to lower through the clamping block 43 and the clamping groove 45. It should be noted that during the lowering process of the stylus mounting cavity 22, since the ball 32 is embedded in the guide groove 34, the position of the slider 23 changes under the restriction of the guide groove 34. Only the stylus mounting cavity 22 drives the plug 27 to lower and disengage from the annular sensitive element 21. At this time, the knob 44 is rotated again to make the knob 44 drive the clamping block 43 to rotate through the mounting ring 42. The clamping block 43 drives the stylus mounting cavity 22 to rotate through the clamping groove 45, thereby achieving the purpose of driving multiple stylus mounting cavities 22 to rotate simultaneously. The sensor stylus 15 in the stylus mounting cavity 22 rotating toward the fixture 14 and the object to be measured will move out with the rotation, while the sensor stylus 15 rotating to other positions will be retracted into the stylus mounting cavity 22 for protection, thereby achieving the purpose of contactless and rapid switching.

[0021] In order to make the mounting ring 42 drop down actively and not reset itself, Figure 6 and Figure 12 As shown, an unlocking mechanism 50 is provided between the rotating rod 41 and the mounting ring 42. The unlocking mechanism 50 includes a connecting rod 51 mounted in the middle of the mounting ring 42 and a push rod 52 passing through the middle of the rotating rod 41. The connecting rod 51 is movably embedded in the rotating rod 41 and the top thereof abuts against the push rod 52. A threaded rod 53 is provided on the top of the push rod 52, and a threaded groove is provided inside the rotating rod 41 to engage with the threaded rod 53. Rotating the threaded rod 53 causes the push rod 52 to descend inside the rotating rod 41 and push the mounting ring 42; By rotating the push rod 52, the push rod 52 rotates and descends under the restriction of the rotating rod 41. A countersink is opened on the top of the rotating knob 44, and the threaded rod 53 is located in the countersink. The distance from the top to the bottom of the countersink is the same as the movable distance of the threaded rod 53, thereby preventing the threaded rod 53 from being too deep and causing damage to the thread. When the push rod 52 is rotated and lowered, the push rod 52 abuts against the connecting rod 51, and an annular groove is provided on the inner wall of the rotating rod 41. A plurality of second guide rods 411 are provided in the groove. A fitting ring 511 is sleeved and installed on the surface of the connecting rod 51, and a through hole for the second guide rod 411 to pass through is provided on the surface of the fitting ring 511. A second spring 412 is wound around the surface of the second guide rod 411 below the fitting ring 511. The two ends of the second spring 412 are respectively connected to the fitting ring 511 and the bottom of the annular groove. Even if the push rod 52 is reversed excessively so that the push rod 52 is completely separated from the connecting rod 51, the connecting rod 51 can still be ensured to be in the rotating rod 41 under the support of the second spring 412, thereby achieving the purpose of limiting the position of the stylus mounting cavity 22 by using the clamping block 43 and the clamping groove 45 so that it cannot move during operation. Driven by the push rod 52, the connecting rod 51 drives the engaging ring 511 to descend under the restriction of the second guide rod 411 and squeezes the second spring 412 to cause it to elastically deform until the mounting ring 42 drives the plug 27 to separate from the annular sensitive element 21 to release the restriction on the stylus mounting cavity 22. Under the restriction of the threaded groove and the threaded rod 53, the mounting ring 42 cannot be reset, and the stylus mounting cavity 22 can rotate normally.

[0022] In order to avoid the rotation of the knob 44 and the rotation of the threaded rod 53 from interfering with each other, Figure 13 As shown, a one-way mechanism 60 is provided in the sensor 13 to limit the rotation direction of the rotating rod 41. The one-way mechanism 60 includes a rotation cavity 61 provided on the sensor 13 and a gear ring 62 sleeved on the surface of the rotating rod 41. The gear ring 62 is rotatably embedded in the rotation cavity 61. The inner wall of the rotation cavity 61 is provided with a plurality of connectors 63 that interlock with the gear ring 62. The connectors 63 limit the gear ring 62 to rotate in only one direction. Preferably, when the knob 44 is rotated counterclockwise, the connector 63 restricts the rotation of the gear ring 62, preventing it from rotating. At this time, if the threaded rod 53 is rotated counterclockwise, the rotating rod 41 cannot rotate. Therefore, the rotation of the threaded rod 53 allows it to rise and fall inside the rotating rod 41 through the thread, thereby achieving the purpose of pushing the mounting ring 42 through the push rod 52 and the connecting rod 51. When the knob 44 drives the gear ring 62 to rotate clockwise in the rotating cavity 61, the connector 63 will not restrict the rotation of the gear ring 62. At this time, the knob 44 drives the rotating rod 41 and the push rod 52 to rotate together, and the threaded rod 53 will not be affected and moves in the rotating rod 41. At this time, the rotating rod 41 can drive the stylus mounting cavity 22 to rotate through the mounting ring 42 and the position of the mounting ring 42 does not change.

[0023] Further, such as Figure 14 As shown, the connector 63 includes a hinge shaft 631 provided on the inner wall of the rotating chamber 61, and a hook 632 is rotatably provided on the hinge shaft 631. The hook 632 and the teeth of the gear ring 62 are both provided with flat surfaces and inclined surfaces. When the flat surface of the teeth of the gear ring 62 abuts the flat surface of the hook 632, the rotating rod 41 cannot rotate. A torsion spring 633 is wound around the hinge shaft 631, and the two ends of the torsion spring 633 are respectively connected to the hook 632 and the hinge shaft 631. When the inclined surface of the teeth of the gear ring 62 abuts the inclined surface of the hook 632, the hook 632 rotates around the hinge shaft 631 as the axis under the push of the inclined surface of the teeth of the gear ring 62 until it moves out of the gap between the teeth of the two gear rings 62. During the rotation, the hook 632 pulls the hinge shaft 631 to undergo elastic deformation, and uses the elastic deformation recovery to pull the hook 632 to quickly reset and re-embed it into the gap between the teeth of the two adjacent gear rings 62.

[0024] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field of the present invention, within the technical scope disclosed by the present invention, can make equivalent replacements or changes to a contour measuring instrument and its inventive concept according to the technology of the present invention, which should be covered by the scope of protection of the present invention.

Claims

1. A profile measuring instrument, comprising a profile measuring instrument body (10), the profile measuring instrument body (10) comprising a test bench (11), a driver (12) mounted on the test bench (11) and capable of being raised and lowered, a sensor (13) disposed at the end of the driver (12), and a plurality of sensor styluses (15) of different diameters mounted on the sensor (13), a fixture (14) mounted on the test bench (11) and located below the sensor styluses (15), a measured object being fixed on the fixture (14), and characterized in that: The sensor (13) is provided with a switching mechanism (20), the switching mechanism (20) comprising an annular sensitive element (21) provided on the sensor (13) and a plurality of stylus mounting cavities (22) provided below the annular sensitive element (21), the stylus mounting cavity (22) rotating about the sensor (13) as an axis and provided with a liftable slider (23) therein, the sensor stylus (15) being slidably mounted on the slider (23) and contacting the object to be measured as the slider (23) descends, and the sensor stylus (15) moves up and down in the slider (23) according to the contour of the surface of the object to be measured; The sensor (13) is further provided with a guide mechanism (30), the guide mechanism (30) comprising an abutment ring (33) provided in the middle of the sensor (13) and a guide groove (34) provided on the surface of the abutment ring (33). The slider (23) drives the sensor stylus (15) to move up and down while also being able to rotate along the trajectory of the guide groove (34). The sensor stylus (15) matching the object to be measured rotates to the top of the fixture (14) and extends out of the stylus mounting cavity (22), and the remaining sensor stylus (15) is received in the stylus mounting cavity (22).

2. A contour measuring instrument according to claim 1, characterized in that: The switching mechanism (20) further includes a plug (27) arranged on the top of the stylus mounting cavity (22) and a spiral cable (26) arranged on the sensor stylus (15). The sensor stylus (15) is connected to the plug (27) via the spiral cable (26), and the plug (27) is inserted into the annular sensitive element (21). When the sensor stylus (15) descends, the spiral cable (26) is pulled to extend and stretch. When the sensor stylus (15) ascends, the spiral cable (26) rebounds and resets.

3. A contour measuring instrument according to claim 1, characterized in that: The guide mechanism (30) further comprises a mounting frame (31) mounted on the slider (23), wherein balls (32) are rollingly embedded in the mounting frame (31), and the balls (32) are rollingly embedded in the guide groove (34) and move along its track.

4. A contour measuring instrument according to claim 3, characterized in that: The switching mechanism (20) further includes two first guide rods (24) arranged inside the stylus mounting cavity (22), the first guide rods (24) passing through the surface of the slider (23) and having a first spring (25) wound around a portion of the surface located above the slider (23), one end of the first spring (25) being connected to the slider (23), and the other end being connected to the top of the inner wall of the stylus mounting cavity (22), and the first spring (25) pulling the ball (32) into contact with the guide groove (34) through a rebound force.

5. A contour measuring instrument according to claim 3, characterized in that: The stylus mounting cavity (22) is connected to the abutment ring (33) via a rotating mechanism (40), the rotating mechanism (40) comprising a rotating rod (41) penetrating the middle of the sensor (13) and rotatably arranged, and a lifting mounting ring (42) mounted at the bottom of the rotating rod (41), and a rotating knob (44) is provided at the top of the rotating rod (41); A plurality of clamping blocks (43) are equidistantly arranged around the mounting ring (42), and a clamping groove (45) that cooperates with the clamping block (43) is installed at the bottom of the stylus mounting cavity (22). When the mounting ring (42) descends, the stylus mounting cavity (22) drives the plug (27) to be withdrawn from the annular sensitive element (21), and the rotating rod (41) is rotated to cause the mounting ring (42) to drive the plurality of stylus mounting cavities (22) to rotate.

6. A contour measuring instrument according to claim 5, characterized in that: An unlocking mechanism (50) is provided between the rotating rod (41) and the mounting ring (42), and the unlocking mechanism (50) comprises a connecting rod (51) mounted in the middle of the mounting ring (42) and a push rod (52) passing through the middle of the rotating rod (41), wherein the connecting rod (51) is movably embedded in the rotating rod (41) and the top thereof abuts against the push rod (52); A threaded rod (53) is provided on the top of the push rod (52), and a threaded groove that meshes with the threaded rod (53) is provided inside the rotating rod (41). The threaded rod (53) is rotated to cause the push rod (52) to descend inside the rotating rod (41) and push the mounting ring (42).

7. A contour measuring instrument according to claim 6, characterized in that: A countersunk hole is provided at the top of the rotating knob (44), the threaded rod (53) is located in the countersunk hole, and the distance from the top to the bottom of the countersunk hole is the same as the movable distance of the threaded rod (53).

8. A contour measuring instrument according to claim 6, characterized in that: An annular groove is provided on the inner wall of the rotating rod (41), and a plurality of second guide rods (411) are provided in the groove. A fitting ring (511) is sleeved and installed on the surface of the connecting rod (51), and a through hole for the second guide rod (411) to pass through is provided on the surface of the fitting ring (511). A second spring (412) is wound around the surface of the second guide rod (411) below the fitting ring (511), and the two ends of the second spring (412) are respectively connected to the fitting ring (511) and the bottom of the annular groove.

9. A contour measuring instrument according to claim 5 or 6, characterized in that: The sensor (13) is provided with a one-way mechanism (60) for limiting the rotation direction of the rotating rod (41). The one-way mechanism (60) includes a rotating cavity (61) provided on the sensor (13) and a gear ring (62) sleeved on the surface of the rotating rod (41). The gear ring (62) is rotatably embedded in the rotating cavity (61). The inner wall of the rotating cavity (61) is provided with a plurality of connectors (63) that engage with the gear ring (62). The connectors (63) limit the gear ring (62) so that it can rotate in only one direction.

10. A contour measuring instrument according to claim 9, characterized in that: The connector (63) includes a hinge shaft (631) provided on the inner wall of the rotating chamber (61), a hook (632) being rotatably provided on the hinge shaft (631), and the teeth of the hook (632) and the tooth ring (62) are both provided with a flat surface and an inclined surface, and when the flat surface of the teeth of the tooth ring (62) abuts against the flat surface of the hook (632), the rotating rod (41) cannot rotate; A torsion spring (633) is wound around the hinge shaft (631), and two ends of the torsion spring (633) are respectively connected to the hook (632) and the hinge shaft (631).

Images