Device and method for finishing welded end face of radio frequency coaxial connector and capable of automatically positioning

Abstract

The invention provides a radio frequency coaxial connector rear-welding end face fine trimming device and method capable of achieving automatic positioning, and the device comprises a tool body, a center distance stripping knife which can be driven and adjusted is installed on the tool body, and a fixing and clamping mechanism is installed at the tail end of the tool body and used for limiting and fixing an outer conductor of a radio frequency cable assembly. An image acquisition mechanism is arranged on one side of the tool body and used for acquiring an image of the fine trimming end face of the radio frequency cable assembly outer conductor. According to the invention, an image is acquired through the image acquisition mechanism, the axial coordinate position of the welded cable end face is obtained through analysis and calculation according to an algorithm through machine vision, and the axial coordinate position of the center distance stripping knife is driven and adjusted on the basis, so that the center distance stripping knife is completely attached to the end face to be repaired; redundant soldering tin or other redundant objects on the end face can be trimmed more accurately and quickly, so that impedance matching of products is guaranteed, return loss is reduced, product performance is improved, and production and assembly efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of radio frequency cable assembly finishing, and in particular to an automatically positioned radio frequency coaxial connector welding rear end surface finishing device and method. Background Art

[0002] In recent years, with the development of equipment and the traction of domestic supporting needs, research on RF transmission technology has been gradually strengthened and achieved good results. However, it is still insufficient in ensuring the high operating frequency of the product, the low voltage standing wave ratio, and the automation of the production process. The trimming of the end face of the existing cable assembly outer conductor after welding generally adopts manual or semi-automatic methods. The manual method is to manually rotate and exploit with a simple rotary cutting tool made of two blades and a mounting handle. The semi-automatic method is to drive the rotary cutting tool through a motor, fix the cable assembly through a clamping device installed on a slide rail, and manually push the cable assembly close to the rotary cutting tool for exploitation. These two methods are still very lacking in processing accuracy, processing consistency and efficiency. It is easy to cause impedance mismatch of RF coaxial transmission lines. When the working frequency band is low, this impact is small, but when the frequency band of RF coaxial cable reaches the millimeter wave band, the impact will be very large; and the processing efficiency of these two methods is too low, which is not suitable for large-scale industrial production. Summary of the invention

[0003] To solve the above problems, the present invention aims to propose an automatically positioned end face finishing device and method for RF coaxial connector welding, so as to achieve end face finishing and automatic positioning after welding of the outer conductor of the RF coaxial cable assembly, and be applicable to connector outer conductors of various specifications.

[0004] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0005] A device for automatically positioning the rear end face finishing of a radio frequency coaxial connector after welding, comprising a tool body, on which a drivable and adjustable center distance stripping knife is installed, a fixed holding mechanism is installed at the end of the tool body for limiting and fixing the outer conductor of a radio frequency cable assembly, and an image acquisition mechanism is arranged on one side of the tool body for acquiring an image of the finished end face of the outer conductor of the radio frequency cable assembly.

[0006] Furthermore, the center distance stripping knife includes a plurality of single-sided sharpened knives arranged in an annular manner, and the fixed holding mechanism is driven by a cylinder.

[0007] Furthermore, the tooling body includes a first bracket, a second bracket, a third bracket and a fourth bracket. The first bracket is rotatably connected to the upper limit position with a screw, and the second bracket, the third bracket and the fourth bracket are sequentially installed on the screw. A driving shaft is rotatably installed between the third bracket and the fourth bracket, and a center distance stripping knife is installed at the rear end of the driving shaft.

[0008] Furthermore, a first servo motor is mounted on the third bracket, and the first servo motor is drivingly connected to the driving shaft.

[0009] Furthermore, a small gear is installed on the driving end of the first servo motor, a large gear is installed on the front end of the driving shaft, and the small gear and the large gear are meshed with each other.

[0010] Furthermore, two guide shafts are installed on the first bracket, and the second bracket, the third bracket and the fourth bracket are slidably installed on the guide shafts.

[0011] Furthermore, a first fixed shaft and a second fixed shaft are installed between the second bracket and the third bracket.

[0012] Furthermore, a second servo motor is mounted on the first bracket, and the second servo motor is connected to the front end of the lead screw through a belt drive.

[0013] In order to achieve the above-mentioned object, the present invention also provides a finishing method of a finishing device for a rear end face of a radio frequency coaxial connector that can be automatically positioned for welding, comprising the following steps:

[0014] S1. Place the outer conductor of the RF cable assembly in the chuck of the fixed clamping mechanism, and the PLC controls the cylinder to drive the chuck to clamp the outer conductor of the RF cable assembly;

[0015] S2, the image acquisition mechanism takes pictures to collect images, obtains the axial coordinates after processing by the visual software algorithm and sends them to the PLC;

[0016] S3, after the PLC obtains the coordinates, it starts the first servo motor, which drives the large gear to rotate through the small gear transmission, thereby driving the center distance stripping knife installed at the rear end of the drive shaft to rotate;

[0017] S4. After a short delay, the second servo motor is started to drive the rotating center distance stripping knife to move axially through the lead screw, gradually approaching the outer conductor end face of the outer conductor of the RF cable assembly to be repaired, and the planes of several circularly arranged single-sided sharpened tools are completely flush with the end face to be repaired and cut until the predetermined coordinates are reached.

[0018] Furthermore, the visual software algorithm is used to process the axial coordinates by edge detection, specifically:

[0019] Step 1: Use the image edge detection algorithm to determine the interface between the solder and the outer conductor, and obtain the physical size L1 from the interface to the edge of the field of view;

[0020] Step 2: Determine the relative distance L2 between the edge of the field of view and the edge of the equipment chuck through the early debugging and installation of the equipment;

[0021] Step 3: The distance L1 between the interface and the edge of the field of view plus the relative distance L2 between the edge of the image field of view and the device chuck is calculated to obtain the relative distance L3 between the interface and the edge of the chuck;

[0022] Step 4: Determine the distance L4 between the first servo motor origin coordinates of the horizontal movement of the tool and the edge of the chuck by setting the chuck position and the first servo motor origin positioning sensor position;

[0023] Step 5: L4-L3 is the absolute distance that the tool moves from the servo origin to the end face of the outer conductor.

[0024] Beneficial effect: The present invention collects images through an image acquisition mechanism, and obtains the axial coordinate position of the cable end face after welding through machine vision based on algorithm analysis and calculation, and uses this as a basis to drive and adjust the axial coordinate position of the center distance stripping knife, so that the center distance stripping knife is completely in fit with the end face to be trimmed, and the excess solder or other excess materials on the end face can be trimmed more accurately and quickly, thereby ensuring the impedance matching of the product, reducing the return loss, improving the product performance, and improving the production and assembly efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0026] Figure 1 It is a front view of the automatically positioned radio frequency coaxial connector welding rear end surface finishing device according to an embodiment of the present invention;

[0027] Figure 2 It is a side view of the automatically positioned radio frequency coaxial connector welding rear end surface finishing device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0028] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0029] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0030] The RF cable assembly consists of an RF coaxial connector and a coaxial cable, wherein the RF coaxial connector is generally composed of an outer shell, an outer conductor, an insulating medium, and an inner conductor. When processing and manufacturing the cable assembly, the outer conductor needs to be welded to the cable shielding layer, and there is often overflow solder on the end face of the outer conductor after welding. At present, manual or semi-automatic methods are generally used to trim the end face of the outer conductor of the cable assembly after welding. The manual method is to manually rotate and exploit with a simple rotary cutting tool made of two blades and a mounting handle. The semi-automatic method is to drive the rotary cutting tool through a motor, fix the cable assembly through a clamping device installed on a slide rail, and manually push the cable assembly close to the rotary cutting tool for exploitation. These two methods still have great deficiencies in product consistency and efficiency.

[0031] Example 1

[0032] Based on the technical defects of the above prior art, see Figure 1-2 : This embodiment is an automatically positioned RF coaxial connector welding rear end face finishing device, including a tool body 1, on which is mounted a drivable and adjustable center distance stripping knife 2, at the end of the tool body 1 is mounted a fixed holding mechanism 3 for limiting and fixing the outer conductor of the RF cable assembly, and one side of the tool body 1 is provided with an image acquisition mechanism 4 for acquiring an image of the finished end face of the outer conductor of the RF cable assembly.

[0033] This embodiment collects images through an image acquisition mechanism, and obtains the axial coordinate position of the cable end face after welding through machine vision based on algorithm analysis and calculation, and uses this as a basis to drive and adjust the axial coordinate position of the center distance stripping knife, so that the center distance stripping knife completely fits the end face to be trimmed, and can more accurately and quickly trim excess solder or other excess materials on the end face, thereby ensuring the impedance matching of the product, reducing return loss, improving product performance, and improving production and assembly efficiency.

[0034] In a specific example, the center distance stripping knife 2 includes a plurality of single-sided sharpened knives arranged in a ring, and the fixed holding mechanism 3 is driven by a cylinder 301 .

[0035] The center distance stripping knife of this embodiment is designed as a plurality of single-sided sharpened knives arranged in a ring, and each single-sided sharpened knife fits the end face to be trimmed, so that the excess solder or other excess materials on the end face can be trimmed more accurately and quickly; the fixed clamping mechanism drives the chuck to clamp the outer conductor through the cylinder, and the control operation is convenient.

[0036] In a specific example, the tool body 1 includes a first bracket 101, a second bracket 102, a third bracket 103 and a fourth bracket 104. The first bracket 101 is rotatably connected to the upper limit position with a screw 5, and the second bracket 102, the third bracket 103 and the fourth bracket 104 are sequentially installed on the screw 5. A drive shaft 6 is rotatably installed between the third bracket 103 and the fourth bracket 104, and a center distance stripping knife 2 is installed at the rear end of the drive shaft 6.

[0037] In this embodiment, the driving shafts on the third bracket and the fourth bracket can be adjusted to move along the axial direction by rotating the lead screw, thereby adjusting the axial coordinate position of the center distance to the stripping knife.

[0038] In a specific example, a first servo motor 7 is installed on the third bracket 103 , and the first servo motor 7 is drivingly connected to the driving shaft 6 .

[0039] In a specific example, a small gear 701 is installed on the driving end of the first servo motor 7 , a large gear 601 is installed on the front end of the driving shaft 6 , and the small gear 701 and the large gear 601 are meshed with each other.

[0040] In this embodiment, the first servo motor is started, and the rotation of the small gear drives the large gear of the mutually meshing drive shaft to rotate, thereby reducing the speed ratio of the drive shaft, so as to achieve stable rotation of the center distance stripping knife at the rear end of the drive shaft, thereby trimming excess solder or other excess materials on the end surface.

[0041] In a specific example, two guide shafts 8 are further installed on the first bracket 101 , and the second bracket 102 , the third bracket 103 and the fourth bracket 104 are slidably installed on the guide shafts 8 .

[0042] In this embodiment, the stability of the screw rotation adjustment can be improved by using two guide shafts, so that the drive shafts on the third bracket and the fourth bracket can move stably along the axial direction.

[0043] In a specific example, a first fixed shaft 9 and a second fixed shaft 10 are further installed between the second bracket 102 and the third bracket 103 .

[0044] In this embodiment, the stability between the second bracket and the third bracket can be improved by the first fixed axis and the second fixed axis, so that the second bracket and the third bracket can move stably and synchronously when the lead screw is adjusted.

[0045] In a specific example, a second servo motor 11 is further mounted on the first bracket 101 , and the second servo motor 11 is drivingly connected to the front end of the lead screw 5 via a belt transmission.

[0046] The second servo motor of this embodiment drives the lead screw to rotate via a belt, thereby adjusting the drive shafts on the third bracket and the fourth bracket to move along the axial direction.

[0047] Example 2

[0048] In order to achieve the above-mentioned purpose, the present embodiment further provides a finishing method of a RF coaxial connector welding rear end surface finishing device capable of automatic positioning, comprising the following steps:

[0049] S1, placing the outer conductor of the RF cable assembly in the clamp of the fixed clamping mechanism 3, and the PLC controls the cylinder 301 to drive the clamp to clamp the outer conductor of the RF cable assembly;

[0050] S2, the image acquisition mechanism 4 takes pictures to collect images, obtains the axial coordinates after processing by the visual software algorithm and sends them to the PLC;

[0051] S3, after the PLC obtains the coordinates, it starts the first servo motor 7, which drives the large gear 601 to rotate through the small gear 701, thereby driving the center distance stripping knife 2 installed at the rear end of the driving shaft 6 to rotate;

[0052] S4, after a short delay, the second servo motor 11 is started to drive the rotating center distance stripping knife 2 to move axially through the screw 5, gradually approaching the outer conductor end face of the outer conductor of the RF cable assembly to be repaired, and the planes of several annularly arranged single-sided sharpened tools are completely flush with the end face to be repaired and cut until the predetermined coordinates are reached.

[0053] The advantages of the automatically positionable RF coaxial connector welding rear end surface finishing method of this embodiment and the automatically positionable RF coaxial connector welding rear end surface finishing device described above over the prior art are the same, and will not be repeated here.

[0054] In a specific example, the processing by the visual software algorithm is to obtain the axial coordinates by edge detection, specifically:

[0055] Step 1: Use the image edge detection algorithm to determine the interface between the solder and the outer conductor, and obtain the physical size L1 from the interface to the edge of the field of view;

[0056] Step 2: Determine the relative distance L2 between the edge of the field of view and the edge of the equipment chuck through the early debugging and installation of the equipment;

[0057] Step 3: The distance L1 between the interface and the edge of the field of view plus the relative distance L2 between the edge of the image field of view and the device chuck is calculated to obtain the relative distance L3 between the interface and the edge of the chuck;

[0058] Step 4: Determine the distance L4 between the first servo motor origin coordinates of the horizontal movement of the tool and the edge of the chuck by setting the chuck position and the first servo motor origin positioning sensor position;

[0059] Step 5: L4-L3 is the absolute distance that the tool moves from the servo origin to the end face of the outer conductor.

[0060] It should be noted that edge detection is a basic problem in image processing and computer vision. The purpose of edge detection is to identify points in digital images where brightness changes significantly. Discontinuities in depth, surface direction, scene lighting changes, and material property changes will all form points where image brightness changes significantly. Edge detection methods mainly include methods based on first-order derivatives and second-order derivatives: commonly used operators include Sobel operators, Prewitt operators, and Roberts operators, etc. In this embodiment, the edge detection method can be used to calculate and obtain the coordinate position of the end face of the outer conductor after welding in real time.

[0061] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An automatically positioned RF coaxial connector welding rear end surface finishing device, characterized in that: The tool body (1) comprises a tool body (1) on which a driveable and adjustable center distance stripping knife (2) is installed; a fixing and holding mechanism (3) is installed at the end of the tool body (1) for limiting and fixing the outer conductor of the radio frequency cable assembly; and an image acquisition mechanism (4) is arranged on one side of the tool body (1) for acquiring an image of the finely trimmed end face of the outer conductor of the radio frequency cable assembly.

2. The automatically positioned radio frequency coaxial connector welding rear end surface finishing device according to claim 1, characterized in that: The center distance stripping knife (2) comprises a plurality of single-sided sharpened knives arranged in an annular manner, and the fixed holding mechanism (3) is driven by a cylinder (301).

3. The automatically positioned radio frequency coaxial connector welding rear end surface finishing device according to claim 1, characterized in that: The tool body (1) comprises a first bracket (101), a second bracket (102), a third bracket (103) and a fourth bracket (104); the first bracket (101) is rotatably connected to an upper limit position with a lead screw (5); the second bracket (102), the third bracket (103) and the fourth bracket (104) are sequentially mounted on the lead screw (5); a driving shaft (6) is rotatably mounted between the third bracket (103) and the fourth bracket (104); a center distance stripping knife (2) is mounted at the rear end of the driving shaft (6).

4. The automatically positioned radio frequency coaxial connector welding rear end surface finishing device according to claim 3, characterized in that: A first servo motor (7) is mounted on the third bracket (103), and the first servo motor (7) is drivingly connected to the drive shaft (6).

5. The automatically positioned radio frequency coaxial connector welding rear end surface finishing device according to claim 4, characterized in that: A small gear (701) is installed on the driving end of the first servo motor (7), a large gear (601) is installed on the front end of the driving shaft (6), and the small gear (701) and the large gear (601) are meshed with each other.

6. The automatically positioned radio frequency coaxial connector welding rear end surface finishing device according to claim 3, characterized in that: Two guide shafts (8) are also installed on the first bracket (101), and a second bracket (102), a third bracket (103) and a fourth bracket (104) are slidably installed on the guide shafts (8).

7. The automatically positioned radio frequency coaxial connector welding rear end surface finishing device according to claim 3, characterized in that: A first fixed shaft (9) and a second fixed shaft (10) are also installed between the second bracket (102) and the third bracket (103).

8. The automatically positioned radio frequency coaxial connector welding rear end surface finishing device according to claim 3, characterized in that: A second servo motor (11) is also mounted on the first bracket (101), and the second servo motor (11) is drivingly connected to the front end of the lead screw (5) via a belt transmission.

9. A finishing method for the automatically positioned RF coaxial connector welding rear end surface finishing device according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1, placing the outer conductor of the radio frequency cable assembly in the clamp of the fixed clamping mechanism (3), and the PLC controls the cylinder (301) to drive the clamp to clamp the outer conductor of the radio frequency cable assembly; S2, the image acquisition mechanism (4) takes pictures to collect images, obtains the axial coordinates after processing by the visual software algorithm and sends them to the PLC; S3, after the PLC obtains the coordinates, it starts the first servo motor (7), which drives the large gear (601) to rotate via the small gear (701), thereby driving the center distance stripping knife (2) installed at the rear end of the driving shaft (6) to rotate; S4. After a short delay, the second servo motor (11) is started to drive the rotating center distance stripping knife (2) to move axially through the lead screw (5), gradually approaching the outer conductor end face of the outer conductor of the RF cable assembly to be repaired, and a plurality of annularly arranged single-sided sharpened tool planes are completely flush with the end face to be repaired and cut until a predetermined coordinate is reached.

10. The finishing method of the automatically positioned RF coaxial connector welding rear end finishing device according to claim 9, wherein the processing by the visual software algorithm is to obtain the axial coordinates by edge detection, specifically: Step 1: Use the image edge detection algorithm to determine the interface between the solder and the outer conductor, and obtain the physical size L1 from the interface to the edge of the field of view; Step 2: Determine the relative distance L2 between the edge of the field of view and the edge of the equipment chuck through the early debugging and installation of the equipment; Step 3: The distance L1 between the interface and the edge of the field of view plus the relative distance L2 between the edge of the image field of view and the device chuck is calculated to obtain the relative distance L3 between the interface and the edge of the chuck; Step 4: Determine the distance L4 between the first servo motor origin coordinates of the horizontal movement of the tool and the edge of the chuck by setting the chuck position and the first servo motor origin positioning sensor position; Step 5: L4-L3 is the absolute distance that the tool moves from the servo origin to the end face of the outer conductor.

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