Proximity sensor axial proximity pitch calibration apparatus and method

Abstract

The application discloses an axial proximity distance calibration device and method for a proximity sensor, which comprises a linear guide rail, a servo motor, a sliding block and a micro-motion platform; the servo motor is fixedly installed at the end of the linear guide rail, the output shaft of the servo motor is connected with a threaded rod parallel to the linear guide rail, the micro-motion platform and the sliding block are slidably connected to the linear guide rail, and the bottom of the micro-motion platform is threadedly connected with the threaded rod; a target is arranged on the micro-motion platform; a proximity sensor circuit board is arranged on the sliding block; a mounting base plate is arranged on the side surface of the linear guide rail, and a proximity sensor shell is arranged on the mounting base plate; the proximity sensor shell is located between the target and the proximity sensor circuit board, and the target, the proximity sensor shell and the proximity sensor circuit board are always located on the same axis along the linear guide rail. The axial installation size between the proximity sensor circuit board and the sensing end of the installation shell thereof can be quickly determined, the qualified rate and the quality of products are improved, and the detection efficiency is greatly improved.

Description

Technical Field

[0001] This invention belongs to the field of sensor testing and relates to a device and method for calibrating the axial proximity distance of a proximity sensor. Background Technology

[0002] A proximity sensor is a component capable of detecting the approach of an object. It utilizes the sensitivity of a displacement sensor to approaching objects to identify their proximity and outputs a corresponding switching signal. During the manufacturing process, the axial mounting dimensions between the proximity sensor circuit board and its mounting housing sensing end must be determined according to the specific specifications of the proximity sensor. Traditionally, axial proximity distance detection is done manually. Due to the large annual production volume of this product, manual inspection is not only time-consuming and labor-intensive but also prone to inaccuracies due to human factors, resulting in a decrease in the sensitivity of the proximity sensor under specified technical requirements. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a proximity sensor axial proximity distance calibration device and method, which can quickly determine the axial mounting dimensions between the proximity sensor circuit board and the sensing end of its mounting housing, thereby improving the product qualification rate and quality, and greatly improving the detection efficiency.

[0004] To achieve the above objectives, the present invention employs the following technical solution:

[0005] A proximity sensor axial proximity distance calibration device includes a linear guide, a servo motor, a slider, and a micro-motion platform;

[0006] The servo motor is fixedly mounted on the end of the linear guide rail. The output shaft of the servo motor is connected to a threaded rod parallel to the linear guide rail. The micro-motion platform and the slider are slidably connected to the linear guide rail. The bottom of the micro-motion platform is threadedly connected to the threaded rod.

[0007] The micro-motion platform is equipped with a target mounting fixture, on which a target is mounted; the slider is equipped with a sensor circuit board mounting fixture, on which a proximity sensor circuit board is mounted; the linear guide rail is equipped with a mounting base plate, on which a sensor housing mounting fixture is mounted, on which a proximity sensor housing is mounted; the proximity sensor housing is located between the target and the proximity sensor circuit board, and the target, proximity sensor housing, and proximity sensor circuit board are always aligned on the same axis along the linear guide rail.

[0008] Preferably, the micro-motion platform includes a micro-motion platform slide and two pairs of U-shaped guide grooves, the linear guide includes two parallel rails, the two pairs of U-shaped guide grooves are slidably connected to the two parallel rails respectively, and the micro-motion platform slide is fixed on the two pairs of U-shaped guide grooves.

[0009] Furthermore, both sides of the two parallel tracks are provided with arc-shaped protrusions, which contact the inner walls of the U-shaped guide grooves on both sides.

[0010] Furthermore, a drive coupling is fixed at the bottom of the micro-motion platform slide, and the drive coupling is threadedly connected to the threaded rod.

[0011] Preferably, a scale is connected parallel to the side of the linear guide rail, and pointers are provided on both the micro-motion platform and the slider, with the pointers facing downwards and the scale located directly below the pointers.

[0012] Preferably, the target mounting fixture includes a target connecting block, a target transition plate, and a target mounting plate. The target connecting block is connected to the top of the micro-motion platform, the target transition plate is connected to the top of the target connecting block, the target mounting plate is connected to the side of the target transition plate, and the target is threadedly connected to the target mounting plate.

[0013] Preferably, the proximity sensor circuit board mounting fixture includes a circuit board connecting block, a circuit board transition plate, and a circuit board mounting plate. The circuit board connecting block is fixed on the top of the slider, the circuit board transition plate is mounted on the top of the circuit board connecting block, and the circuit board mounting plate is mounted on the top of the circuit board transition plate. Semi-circular through slots are respectively provided between the circuit board mounting plate and the circuit board transition plate. The two semi-circular through slots cooperate to form a circular through slot, and the end of the proximity sensor circuit board is inserted into the circular through slot.

[0014] Furthermore, the circuit board transition plate is provided with two oval through holes, and bolts are used to connect it to the top of the circuit board connecting block through the two oval through holes.

[0015] Preferably, the proximity sensor circuit board is connected to a PLC, the PLC is connected to a host computer and a servo driver, the output of the servo driver is connected to the input of the servo motor, and the servo motor is connected to an encoder.

[0016] A method for calibrating the axial proximity distance of a proximity sensor based on any one of the above-described devices includes the following steps:

[0017] Manually adjust the slider to insert the proximity sensor circuit board into a certain position in the proximity sensor housing. The servo motor drives the micro-motion platform to move on the linear guide rail, thereby causing the target to move back and forth along the axial direction of the linear guide rail. The axial proximity distance of the proximity sensor is calibrated until the proximity sensor sensitivity technical requirements are met. The target position is obtained, and the axial installation dimension between the proximity sensor circuit board and the sensing end of the proximity sensor housing is determined by the displacement difference.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The target of this invention is fixedly installed on the micro-motion platform via a target mounting fixture. The proximity sensor housing is fixedly installed on the mounting base plate via a sensor housing mounting fixture. The proximity sensor circuit board is fixedly installed on the slider via a proximity sensor circuit board mounting fixture. The micro-motion platform and the slider are slidably installed on a linear guide rail. A servo motor provides the driving force, and the linear guide rail provides guidance, which improves the detection accuracy, effectively ensures the sensitivity of the product, and makes the entire calibration device simple and compact in structure. It accurately positions the three components relative to the terminal, improves the positioning accuracy, and reduces the difficulty of installation and debugging during the detection process.

[0020] Furthermore, the arc-shaped protrusions of the parallel track contact the inner walls on both sides of the U-shaped guide groove, making the sliding mode linear, which greatly reduces friction and effectively ensures the smooth sliding of the micro-motion platform.

[0021] Furthermore, the scale improves reading accuracy and ensures positioning precision.

[0022] Furthermore, the target is fixed to the target mounting fixture using a threaded connection, which not only improves positioning accuracy but also makes the threaded connection simple and easy to assemble and disassemble.

[0023] Furthermore, the proximity sensor circuit board adopts a slot-type mounting method, which is fixedly installed with the circuit board mounting plate and the circuit board transition plate. The installation method is simple in structure, easy to disassemble and assemble, and can ensure that the proximity sensor circuit board is always in a horizontal state.

[0024] Furthermore, the connection holes between the circuit board transition plate and the circuit board connecting block are connected by oval through holes, which can finely adjust the position of the proximity sensor circuit board along the longitudinal direction of the linear guide rail according to the detection requirements. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the axial proximity distance calibration device for the proximity sensor of the present invention;

[0026] Figure 2 This is a schematic diagram of the cross-sectional structure of the micro-motion platform and linear guide rail of the present invention;

[0027] Figure 3 This is a schematic diagram of the bottom structure of the micro-motion platform of the present invention;

[0028] Figure 4 This is a schematic diagram showing the connection between the arc-shaped protrusion and the U-shaped guide groove of the present invention;

[0029] Figure 5 This is a schematic diagram of the target mounting fixture structure of the present invention;

[0030] Figure 6 This is a schematic diagram of the proximity sensor circuit board mounting fixture structure of the present invention;

[0031] Figure 7 This is a schematic diagram of the circuit board mounting plate and circuit board transition plate structure of the present invention;

[0032] Figure 8 This is a schematic diagram of the electrical connections of the present invention;

[0033] Figure 9 This is a flowchart of the servo motor control process of the present invention.

[0034] The components are: 1. Linear guide rail, 2. Target mounting fixture, 3. Target, 4. Proximity sensor housing, 5. Proximity sensor circuit board, 6. Sensor circuit board mounting fixture, 7. Slider, 8. Mounting base plate, 9. Sensor housing mounting fixture, 10. Pointer, 11. Scale, 12. Micro-motion platform, 13. Servo motor, 14. U-shaped guide groove, 15. Micro-motion platform slide, 16. Drive coupling, 17. Target connecting block, 18. Target transition plate, 19. Target mounting plate, 20. Circuit board connecting block, 21. Circuit board transition plate, 22. Circuit board mounting plate. Detailed Implementation

[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0036] It should be noted that the terms “front,” “back,” “left,” “right,” “up,” and “down” used in the following description refer to the directions shown in the attached diagram, while the terms “inside” and “outside” refer to the directions toward or away from the geometric center of a specific component, respectively.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0038] like Figure 1As shown, the proximity sensor axial proximity distance calibration device of the present invention includes a linear guide rail 1, which is screwed and mounted on a mounting base plate 8. A servo motor 13 is fixedly mounted on the end of the linear guide rail 1. The output shaft of the servo motor 13 is connected to a threaded rod parallel to the linear guide rail 1. A micro-motion platform 12 is slidably connected on the linear guide rail 1. The bottom of the micro-motion platform 12 is threadedly connected to the threaded rod. The servo motor 13 provides driving force to drive the micro-motion platform 12 to perform linear reciprocating motion along the linear guide rail 1.

[0039] The target mounting fixture 2 is fixedly connected to the micro-motion platform 12 by screws, and the target 3 is installed on the target mounting fixture 2 by threaded connection.

[0040] A scale 11 is connected parallel to the side of the linear guide rail 1. A pointer 10 is fixed to the micro-motion platform 12 and the slider 7 with screws. The pointer 10 is set downwards, and the scale 11 is located directly below the pointer 10. The servo motor 13 drives the micro-motion platform 12 to make the target 3 move linearly along the linear guide rail 1. The displacement value on the scale 11 is read by the pointer 10.

[0041] The slider 7 is slidably connected to the linear guide rail 1. The sensor circuit board mounting fixture 6 is fixedly installed on the slider 7 by screw connection. The proximity sensor circuit board 5 is fixedly installed on the sensor circuit board mounting fixture 6. During operation, the slider 7 is manually adjusted to a fixed position, and the displacement value on the scale 11 is read by the pointer 10.

[0042] A mounting base plate 8 is provided on the side of the linear guide rail 1. The bottom of the sensor housing mounting fixture 9 is connected to the mounting base plate 8 by screws. The proximity sensor housing 4 is fixed to the top of the sensor housing mounting fixture 9 by threads. The target 3, the proximity sensor housing 4, and the proximity sensor circuit board 5 are always on the same axis along the linear guide rail 1.

[0043] In this invention, the micro-motion platform 12 and the linear guide rail 1 are shown in the following schematic diagram. Figure 2As shown in Figure 4, the micro-motion platform 12 includes a micro-motion platform slide 15 and two pairs of U-shaped guide grooves 14. The two pairs of U-shaped guide grooves 14 are used to cooperate with the arc-shaped guide rails on the linear guide rail 1 for guidance and positioning. The track portion of the linear guide rail 1 has arc-shaped protrusions on both sides to form arc-shaped guide rails. The arc-shaped protrusions contact the inner walls of the two sides of the U-shaped guide grooves 14. The two pairs of U-shaped guide grooves 14 are symmetrically fixed on the micro-motion platform slide 15 with screws, as shown in Figure 3. The drive coupling 16 is fixedly installed on the micro-motion platform slide 15 and is threadedly connected to the threaded rod to transmit the driving force of the servo motor 13 to the micro-motion platform slide 15, driving the micro-motion platform slide 15 to move. The use of U-shaped guide grooves 14 and arc-shaped guide rails for guidance and positioning not only improves the positioning accuracy, but also makes the sliding type linear, greatly reducing friction and effectively ensuring the smooth sliding of the micro-motion platform.

[0044] In this invention, the target mounting fixture 2 is shown in the following schematic diagram. Figure 5 As shown, it includes a target connecting block 17, which is installed on the micro-motion platform slide 15 by screw connection. The target transition plate 18 is installed on the target connecting block 17 by screw connection. The target mounting plate 19 is installed on the target transition plate 18 by screw connection. The target 3 is installed on the target mounting plate 19 by threaded connection. This structure adopts screw fastening connection and threaded installation. Its structure is simple and compact, easy to install and disassemble, and reduces the difficulty of installation and debugging.

[0045] In this invention, the schematic diagram of the proximity sensor circuit board mounting fixture 6 is shown in Figure 6. It includes a circuit board connecting block 20, which is mounted on the slider 7 via screws. A circuit board transition plate 21 is mounted on the circuit board connecting block 20 via screws. The circuit board mounting plate 22 and the circuit board transition plate 21 are connected by four screws. As shown in Figure 7, semi-circular through slots are respectively provided between the circuit board mounting plate 22 and the circuit board transition plate 21. The two semi-circular through slots cooperate to form a circular through slot. The end of the proximity sensor circuit board 5 is inserted into the circular through slot. The proximity sensor circuit board 5 adopts a slot-type mounting structure, which is simple and compact, easy to install and disassemble, and ensures that the circuit board is in a horizontal state, effectively protecting the circuit board from damage. Simultaneously, the connection hole between the circuit board transition plate 21 and the circuit board connecting block 20 adopts a slot-shaped hole feature, allowing for fine adjustment of the longitudinal position of the proximity sensor circuit board 1 along the longitudinal direction of the linear guide rail 1 according to detection requirements.

[0046] The overall design functional block diagram of this invention is as follows: Figure 8As shown, to ensure precise target feeding, a closed-loop control system is formed by the host computer, programmable logic controller (PLC), servo driver, servo motor 13, actuator, and proximity sensor circuit board 5. The proximity sensor circuit board 5 is connected to the PLC, which in turn is connected to the host computer and the servo driver. The output of the servo driver is connected to the input of the servo motor 13, which is connected to an encoder. The servo motor 13 controls the proximity sensor circuit board 5 through the actuator, which in this embodiment is a micro-motion platform 12, working in close coordination. Through the coordinated operation of the target mounting fixture 2, mounting base plate 8, and micro-motion platform 12, the axial proximity distance calibration of the proximity sensor is completed.

[0047] In this invention, the control flowchart of servo motor 13 is as follows: Figure 9 As shown, a power-on self-test is first required to check whether the servo motor 13 is in the zero position and determine the designated position of the target 3. The host computer inputs the set position parameters according to the detection requirements. When the target 3 reaches the designated position, the proximity sensor circuit board 5 feeds back the on / off signal to the servo driver. The test is run again according to the set position parameters to confirm the accuracy of the detection position.

[0048] The process of calibrating the axial proximity distance of the proximity sensor is as follows: Manually adjust the slider 7, insert the proximity sensor circuit board 5 into the proximity sensor housing 4 at a certain position, read the value of the scale 11 through the pointer 10 to determine the insertion distance, input the set position parameters into the host computer according to the detection requirements, drive the micro-motion platform 12 to move on the linear guide rail 1 through the servo motor 13, thereby driving the target 3 to move back and forth along the axial direction of the linear guide rail 1 to calibrate the axial proximity distance of the proximity sensor until the proximity sensor sensitivity technical requirements are met, read the displacement value on the servo motor encoder, that is, the position of the target 3, and thus determine the axial installation dimension between the proximity sensor circuit board 5 and the sensing end of the proximity sensor housing 4 through the displacement difference.

[0049] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0050] It should be understood that the above description is for illustrative purposes and not for limitation. Many embodiments and applications beyond the provided examples will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this patent should not be determined by reference to the above description, but rather by reference to the foregoing claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended as a waiver of that subject matter, nor should it be construed as an indication that the applicant has not considered that subject matter as part of the disclosed inventive subject matter.

Claims

1. A proximity sensor axial proximity distance calibration device, characterized in that, It includes a linear guide (1), a servo motor (13), a slider (7), and a micro-motion platform (12). The servo motor (13) is fixedly installed at the end of the linear guide (1). The output shaft of the servo motor (13) is connected to a threaded rod parallel to the linear guide (1). The micro-motion platform (12) and the slider (7) are slidably connected on the linear guide (1). The bottom of the micro-motion platform (12) is threadedly connected to the threaded rod. A target mounting fixture (2) is provided on the micro-motion platform (12), and a target (3) is provided on the target mounting fixture (2); a sensor circuit board mounting fixture (6) is provided on the slider (7), and a proximity sensor circuit board (5) is provided on the sensor circuit board mounting fixture (6); a mounting base plate (8) is provided on the side of the linear guide rail (1), and a sensor housing mounting fixture (9) is provided on the mounting base plate (8), and a proximity sensor housing (4) is provided on the sensor housing mounting fixture (9); the proximity sensor housing (4) is located between the target (3) and the proximity sensor circuit board (5), and the target (3), the proximity sensor housing (4), and the proximity sensor circuit board (5) are always on the same axis along the linear guide rail (1); The micro-motion platform (12) includes a micro-motion platform slide (15) and two pairs of U-shaped guide grooves (14). The linear guide rail (1) includes two parallel rails. The two pairs of U-shaped guide grooves (14) are slidably connected to the two parallel rails respectively. The micro-motion platform slide (15) is fixed on the two pairs of U-shaped guide grooves (14). The proximity sensor circuit board (5) is connected to a PLC, the PLC is connected to a host computer and a servo driver, the output of the servo driver is connected to the input of the servo motor (13), and the servo motor (13) is connected to an encoder. The target mounting fixture (2) includes a target connecting block (17), a target transition plate (18), and a target mounting plate (19). The target connecting block (17) is connected to the top of the micro-motion platform (12), the target transition plate (18) is connected to the top of the target connecting block (17), the target mounting plate (19) is connected to the side of the target transition plate (18), and the target (3) is threadedly connected to the target mounting plate (19). The proximity sensor circuit board mounting fixture (6) includes a circuit board connecting block (20), a circuit board transition plate (21), and a circuit board mounting plate (22). The circuit board connecting block (20) is fixed on the top of the slider (7). The circuit board transition plate (21) is mounted on the top of the circuit board connecting block (20). The circuit board mounting plate (22) is mounted on the top of the circuit board transition plate (21). Semi-circular through slots are respectively provided between the circuit board mounting plate (22) and the circuit board transition plate (21). The two semi-circular through slots cooperate to form a circular through slot. The end of the proximity sensor circuit board (5) is inserted into the circular through slot. The circuit board transition plate (21) has two oval through holes, and bolts are used to connect it to the top of the circuit board connecting block (20) through the two oval through holes.

2. The proximity sensor axial proximity distance calibration device according to claim 1, characterized in that, Both sides of the two parallel tracks are provided with arc-shaped protrusions, which are in contact with the inner walls of the U-shaped guide groove (14) on both sides.

3. The proximity sensor axial proximity distance calibration device according to claim 1, characterized in that, The bottom of the micro-motion platform slide (15) is fixed with a drive coupling (16), which is threadedly connected to the threaded rod.

4. The proximity sensor axial proximity distance calibration device according to claim 1, characterized in that, A scale (11) is connected parallel to the side of the linear guide (1). A pointer (10) is set on both the micro-motion platform (12) and the slider (7). The pointer (10) is set downwards, and the scale (11) is located directly below the pointer (10).

5. A method for calibrating the axial proximity distance of a proximity sensor based on the device according to any one of claims 1-4, characterized in that, Includes the following processes: Manually adjust the slider (7) and insert the proximity sensor circuit board (5) into the proximity sensor housing (4) at a certain position. The servo motor (13) drives the micro-motion platform (12) to move on the linear guide rail (1), thereby driving the target (3) to move back and forth along the axial direction of the linear guide rail (1). The axial proximity distance of the proximity sensor is calibrated until the proximity sensor sensitivity technical requirements are met. The position of the target (3) is obtained, and the axial installation dimension between the proximity sensor circuit board (5) and the sensing end of the proximity sensor housing (4) is determined by the displacement difference.

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