Processing method of bed frame structure

Abstract

The invention relates to the technical field of metal structure welding machining, in particular to a machining method of a bed frame structure. The cut pipes are positioned through a tool so as to complete welding preparation; two sets of through holes are formed in the side faces, connected with the cross beams, of the edge beams and correspond to the installation position of one end of each cross beam, and each set comprises two through holes between which a strain bridge is formed. The processing method comprises the following steps: attaching a strain gauge on the inner wall of the hollow cavity of the boundary beam corresponding to the position of the strain bridge; four-point spot welding positioning of the cross beam is conducted on the strain bridge at the two ends of the cross beam in the length direction, and after welding is completed, positioning of the cross beam by the tool is relieved; and monitoring data of the strain gauges, and when data conditions are met, carrying out full-length welding on the connecting positions of the boundary beams and the cross beams. By means of the method, hidden torsional deformation at the joint of the cross beam and the edge beam after spot welding can be effectively prevented, and therefore the problems of diagonal line out-of-tolerance, abnormal sound and the like caused by subsequent full welding solidification defects are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of metal structure welding processing, in particular to a processing method of a bed frame structure. Background Art

[0002] In the existing bed frame manufacturing method, the pipes are first cut and blanked, and the pipes are accurately cut into pipe sections of the required length according to the drawing dimensions. During the welding and assembly process, the cut and formed parts are initially positioned and fixed on the welding tooling by spot welding, and then firmly welded automatically.

[0003] In the above process, spot welding first and then full welding can reduce the probability of obtaining defective products with distortion and out-of-tolerance dimensions. In the manufacture of iron bed frames, hidden torsional deformation of pipes after spot welding is a common problem that leads to poor product consistency. The specific situation is as follows: During the spot welding process, due to uneven release of thermal stress, invisible torsional deformation occurs inside the pipe, which cannot be identified by traditional caliper measurement. The tiny torsion in the spot welding stage is solidified in the subsequent full welding, eventually leading to structural defects such as "diagonal deviation" or "uneven four legs" when the entire bed is assembled. Summary of the Invention

[0004] The present invention provides a method for processing a bed frame structure, which can effectively solve the problems in the background technology.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: A method for processing a bed frame structure includes cutting pipes according to design drawings; positioning the cut pipes using tooling to prepare for welding; The bed frame structure includes side beams on both sides and at least two cross beams connecting the side beams on both sides. The side beams are hollow, and the inner and outer contours of the cross section are both hollow rectangles. The outer contour of the cross beam cross section is rectangular. On the side where the side beams are connected to the cross beams, two groups of through holes are provided corresponding to the installation position of one end of each cross beam. Each group includes two through holes forming a strain bridge therebetween. The two strain bridges are respectively located on both sides of one end of the cross beam and serve as spot welding positions for the side beams and the cross beam. Processing methods include: A strain gauge is attached to the inner wall of the hollow cavity of the side beam at a position corresponding to the strain bridge; At both ends of the beam in the longitudinal direction, four-point spot welding is performed on the strain bridge to position the beam. After welding is completed, the positioning of the beam by the tooling is released; The data of each strain gauge is monitored, and when the data conditions are met, full welding is performed at the connection position between the side beam and the cross beam.

[0006] Furthermore, the fully welded cladding area covers the strain bridge and the through hole.

[0007] Further, the strain gauges are fixed on the inner wall of the hollow cavity of the side beam.

[0008] Further, the through holes are waist-shaped hole positions, and the length direction of the waist-shaped hole positions is arranged along the length direction of the side beam.

[0009] Further, the strain bridges on both sides of one end of the cross beam correspond to the center positions of the edges of the cross beam.

[0010] Further, the data condition is satisfied, including: The monitoring values of the four strain gauges corresponding to each cross beam are within a first set range, and the variance between the four monitoring values is within a second set range.

[0011] Further, the data condition is satisfied, including: Within a set time range, the variance of the real-time data change rates of the four strain gauges is within a third set range.

[0012] Further, the tool includes an object detection device, which detects at least before the tool releases the positioning of the cross beam, and the release of positioning and full welding are performed when the detection result is that there is no object within a set range around the tool.

[0013] Further, the spacing between the through holes in the same group is 5-15 mm.

[0014] Further, compressed air is introduced into the inside of the side beam, the compressed air flows for a time covering the spot welding process, and the data monitoring process of the strain gauges.

[0015] Further, the compressed air flows in a vortex shape.

[0016] Through the technical scheme of the present application, the following technical effects can be achieved: Through the present application, the hidden torsional deformation of the connection between the cross beam and the side beam after spot welding can be effectively prevented, thereby avoiding the problems of diagonal line out-of-tolerance and abnormal sound caused by solidification defects after subsequent full welding. In the implementation process, a temporary sensor structure is obtained by combining the strain bridge and the strain gauge during the spot welding stage. After the two ends of each cross beam are fixed relative to the side beam through two spot welding positions, the four strain bridges are the actual beam connection positions. Due to the relatively small cross-sectional size, the strain bridges have more sensitive deformation sensing ability and can capture torsional data in real time to realize quality judgment before full welding. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description only represent some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0018] Figure 1 Structure diagram for fixing the bed frame structure by tooling; Figure 2 Top view of the bed frame structure fixed by tooling; Figure 3 Top view of the bed frame structure; Figure 4 Partial view of the bed frame structure showing through holes and spot welding positions of different shapes; Figure 5 Partial view of the bed frame structure showing strain gauge positions; Figure 6 Process diagram of the bed frame structure from spot welding to full welding; Figure 7 Flow chart of the bed frame structure processing method.

[0019] Reference signs: 01, side beam; 011, side surface; 012, through hole; 013, strain bridge; 014, spot welding point; 02, cross beam; 03, tooling; 031, transverse extrusion point; 032, longitudinal extrusion point; 033, limiting point; 04, strain gauge. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments only represent some embodiments of the present application, not all embodiments.

[0021] As shown in Figures 1-6 A processing method of a bed frame structure, first, according to the design drawing, the pipe material is cut; the tooling 03 is used to position the cut pipe material to complete the welding preparation.

[0022] In this embodiment, the bed frame structure includes side beams 01 on both sides and at least two cross beams 02 connecting the side beams 01 on both sides. The side beams 01 are hollow, and the inner and outer contours of the cross section are both hollow rectangles. The outer contour of the cross section of the cross beam 02 is a rectangle. On the side surface 011 where the side beams 01 and the cross beams 02 are connected, two groups of through holes 012 are provided corresponding to the installation position of one end of each cross beam 02. Each group includes two through holes 012 forming a strain bridge 013 therebetween. The two strain bridges 013 are respectively located on both sides of one end of the cross beam 02 and serve as spot welding positions for the side beams 01 and the cross beam 02. like Figure 7 As shown, the processing method includes: S1: A strain gauge 04 is attached to the inner wall of the hollow cavity of the side beam 01 at a position corresponding to the strain bridge 013; S2: At both ends of the beam 02 in the longitudinal direction, four spot welding positions of the beam 02 are performed on the strain bridge 013, such as Figure 4 As shown, the location of spot welding point 014 is shown. After welding is completed, the positioning of the crossbeam 02 by the tooling 03 is released; S3: Monitor the data of each strain gauge 04. When the data conditions are met, perform full welding of the connection position between the side beam 01 and the cross beam 02.

[0023] The present invention effectively prevents hidden torsional deformation at the connection between crossbeam 02 and side beam 01 after spot welding, thereby avoiding problems such as diagonal deviations and abnormal noise caused by subsequent full weld solidification defects. During implementation, a temporary sensor structure is formed by combining strain bridge 013 and strain gauge 04 during the spot welding stage. After each crossbeam 02 is fixed relative to the side beam 01 via two spot welds at each end, the four strain bridges 013 represent the actual beam connection locations. Given their relatively small cross-sectional dimensions, they have more sensitive deformation sensing capabilities, enabling real-time capture of torsion data and enabling quality assessment before full welding.

[0024] The design of the hollow side beam 01 creates thermal zones between the inner wall's strain gauge 04 installation location and the outer wall's spot welding locations. Data monitoring time can be controlled within 5 minutes, effectively reducing the thermal impact on the strain gauge 04. The pipe wall naturally insulates welding spatter, preventing contamination of the strain gauge 04. After data monitoring is completed, the strain gauge 04 can be removed or retained within the side beam 01. In this application, even if the strain gauge 04 remains on the inner wall of the side beam 01, it does not affect the product's aesthetics. Specifically, in this implementation, the strain gauge 04 is used as a consumable and retained on the inner wall of the side beam 01, and its service life at high temperatures only needs to be controlled within the aforementioned 5 minutes.

[0025] See Figures 1-5As a specific embodiment, the embodiment shows the case of having two side beams 01 and three cross beams 02, one of which is located at the bed tail, and two of which are located at the bed head, of course, which does not limit the protection scope of the present application. In the process of using the bed frame structure, the side beam 01 directly bears the bending moment of the body sitting pressure impact, and the cross beam 02 bears the uniform load of the bed plate. The node of the side beam 01 and the cross beam 02 often needs to bear the bending-torsional composite stress, so it is the position of concern in the present application.

[0026] For the structure of the tool 03, it often includes the following structures shown in Figure 1 and 2 . The transverse extrusion point 031 is parallel to the extrusion direction of the bed frame, and the pipe is extruded from both sides, which has a power structure. The longitudinal extrusion point 032 is perpendicular to the extrusion direction of the bed frame, and the pipe is extruded, which has a power structure. The limiting point 033 only limits the pipe through a groove, etc., and does not have a power structure.

[0027] The above positioning methods can be flexibly selected according to the actual bed frame structure. In the embodiment, the transverse extrusion point 031 and the longitudinal extrusion point 032 are used for the side beam 01; only the transverse extrusion point 031 is used for the cross beam 02 at the bed tail, and in this case, after welding, the positioning of the tool 03 to the cross beam 02 is released, that is, the extrusion force of the transverse extrusion point 031 is released; for the two cross beams 02 at the bed head, the limiting point 033 and the longitudinal extrusion point 032 are used for comprehensive positioning, and in this case, after welding, the positioning of the tool 03 to the cross beam 02 is released, that is, the extrusion force of the longitudinal extrusion point 032 is released. Since the limiting point 033 is often in clearance fit with the pipe, the torsion of the cross beam 02 can also be allowed to be reflected under the condition of no extrusion force.

[0028] The data of each strain gauge 04 is monitored, and when the data condition is not met, the abnormal situation can be investigated according to the actual situation, including but not limited to pipe quality inspection, tool quality inspection, and welding parameter adjustment, etc. In the case where the data condition is not met, the cross beam 02 needs to be separated from the side beam 01, which can be directly carried out on the tool 03, maintaining the positioning of the tool 03 to the side beam 01, while releasing the positioning of the cross beam 02. Since the welding area of the spot welding point 014 is limited, the separation is easy to realize.

[0029] As the preferred embodiment of the above embodiment, as shown in Figure 6As shown, the full-welded cladding zone covers the strain bridge 013 and the through hole 012; in this way, the structure is restored at zero cost, the hole is filled with welding material, the surface tension of the molten solder is relatively low, and it spontaneously penetrates into the through hole 012 under the action of gravity and arc blowing force, and the high temperature of the molten pool causes the base metal at the hole edge to be slightly melted, forming a diffusion metallurgical bonding layer.

[0030] As a fixing method of the strain gauge 04, the strain gauge 04 is pasted and fixed on the inner surface of the edge beam 01. This method can reduce the distortion degree of strain transmission and is convenient to operate. In the specific installation and setting, the strain gauge 04 with adhesive material can be fixed by a rod-shaped structure. The strain gauge 04 is transmitted to the position corresponding to the strain bridge 013 by moving the rod-shaped structure into the hollow cavity of the edge beam 01, and then pressure bonding is implemented. Specifically, the moving position of the strain gauge 04 can be controlled by pre-setting the moving track. This method can be realized by a predetermined program, or a camera and a light can be installed at the end of the rod-shaped structure. During the movement of the rod-shaped structure, the final position is determined by image recognition. The above methods are within the protection scope of the present application, and the specific implementation can be selected according to the processing equipment, cost and other factors.

[0031] As a preferred embodiment of the above embodiment, the through hole 012 is a waist-shaped hole position, and the length direction of the waist-shaped hole position is arranged along the length direction of the edge beam 01. Figure 4 As shown, two enlarged positions respectively show two cases that the through hole 012 is a round hole and a waist-shaped hole. The round hole is convenient to process, but compared with the waist-shaped hole, the waist-shaped hole position can make the strain bridge 013 obtain a bridge structure that is more suitable for the installation of the strain gauge 04 and the change of torsion, and improve the sensitivity of data monitoring.

[0032] As a preferred embodiment of the above embodiment, the strain bridges 013 on both sides of one end of the cross beam 02 correspond to the center positions of the edges of the cross beam 02, so as to maintain symmetry. Through symmetrical data acquisition, the monitoring noise can be reduced, and the influence of spot welding can also be self-balanced to a large extent.

[0033] As a preferred embodiment of the above embodiment, the data conditions include: The monitoring values of the four strain gauges 04 corresponding to each cross beam 02 are within the first set range, and the variance between the four monitoring values is within the second set range. The first set range and the second set range can be set according to experiments or operator experience, and can also be adjusted in detail to be more suitable for actual working conditions during operation.

[0034] For the two conditions of the above embodiments, the former ensures that the results monitored by each strain gauge 04 are at an acceptable absolute level, verifying whether the overall deformation of the end of the welded beam 02 exceeds the safety threshold; the latter ensures that the readings of the four strain gauges 04 are close to each other and uniformly distributed, verifying whether the deformation of the end of the welded beam 02 is uniform and symmetrical, and identifying whether unexpected unilateral bending or twisting occurs; the qualified state determined by both is more reliable.

[0035] As another implementation, satisfying the data condition includes: The variance of the real-time data change rate of the four strain gauges 04 within a set time range is within a third set range. The real-time dynamics here is achieved through multiple acquisitions, and as in the above embodiment, the specific acquisition frequency and the third set range can be set according to experiments or operator experience, and can also be adjusted in detail during operation to better suit actual working conditions.

[0036] This way changes the judgment method based on static results to a dynamic monitoring method within a set time period, which can ensure uniform and stable thermodynamic behavior, and through reasonable selection of the time range, the whole process from thermal expansion to cooling contraction can be effectively monitored, further improving the quality of the final product.

[0037] As a preferred embodiment of the above, the tooling 03 includes an object detection device that detects at least before the tooling 03 is released from positioning the beam 02, and both releasing the positioning and full welding are performed when the detection result is that there is no object within a set range around the tooling 03; the following is an example description of the object detection implementation, which can be selected as needed during implementation: (1) The object detection device can construct a three-dimensional digital twin model of the tooling area in real time through 100-200 thousand point cloud scans per second, which can be performed by a 3D-ToF laser radar installed on the tooling, automatically classify object types such as people, equipment, and spatter through deep learning algorithms, predict collision risks in combination with welding trajectories, and through this way, sudden intruders can be stopped within 0.2 seconds; (2) The object detection device can use a dual-spectrum thermal imager deployed on the tooling frame to simultaneously capture visible light object outlines and thermal radiation characteristics, automatically release known tools through AI comparison with the bill of materials, and quickly respond to intruders; (3) The object detection device can use a UWB base station array deployed on the tooling frame to work with active positioning tags equipped by personnel or equipment to form a digital fence, thereby dynamically isolating the welding gun working area and quickly responding to objects that intrude into the digital fence.

[0038] In the preferred embodiment, based on the setting of the object detection device, the safety of the tool when positioning the cross beam can be ensured, and the four spot welding points may be affected under torsion. As a more optimal way, the object detection device can start working before the tool positions all the pipes, for example, the device is activated 5s before the tool positions the pipes, and a protection covering the entire cycle of the tool operation is constructed. Through the setting of the device, the welding process is more intelligent and safe, and based on the real-time spatial perception of the warning area, the risks of personnel intrusion and equipment boundary crossing can be quickly responded to, and finally through the undisturbed welding environment control, the strain gauge monitoring data is ensured not to be disturbed.

[0039] In the specific implementation process, specific working conditions can be set based on the detection results, for example: The trigger condition for the tool to release positioning and full welding action is that no object intrudes into the warning area around the tool 03 for more than 2 seconds, and the range of the warning area can be set according to the actual production space.

[0040] As a preferred embodiment of the above example, the spacing between the through holes 012 in the same group is 5-15mm, so as to ensure that the strain gauge 04 obtains an effective installation position.

[0041] In the above example, although the time of data monitoring is reasonably controlled, the temperature rise caused by spot welding may also affect data monitoring. In order to solve this problem, as a preferred embodiment of the above example, compressed air is introduced into the inside of the side beam 01, and the compressed air flow time covers the spot welding process and the data monitoring process of the strain gauge 04.

[0042] In the preferred embodiment, by continuously introducing compressed air into the inside of the side beam 01, a dynamic thermal isolation barrier can be constructed during the cooling process, so that the temperature of the strain gauge 04 substrate is always within the acceptable range, and the risks of carbonization of the adhesive layer, zero drift, etc. caused by the temperature of spot welding are reduced; compressed air is a normal temperature gas, which will not affect the spot welding process in the implementation process, and the main effect is to affect the temperature of the inner surface of the side beam 01 attached to the strain gauge 04, so as to ensure the accuracy of the monitoring process.

[0043] In order to avoid the outflow of compressed air from the through hole 012 affecting the spot welding process, as a preferred embodiment of the above example, the compressed air flows in a vortex shape; this way can set a spiral guide structure at the outlet of the air pipe to make the airflow generate axial spinning power, combined with the control of the air supply pressure, so that the compressed air can not flow out of the through hole 012 as much as possible, or a small amount of outflow. In the implementation process, the cost of compressed air is relatively low, and it can be freely discharged from the other end of the side beam 01. By increasing the gas flowability, the relative stability of the temperature of the strain gauge 04 installation position can be maintained, and the accuracy of the monitoring can be improved.

[0044] Those skilled in the art should understand that the present application is not limited by the above-mentioned embodiments, the above-mentioned embodiments and descriptions in the specification are only to illustrate the principles of the present application, and various changes and improvements can be made to the present application without departing from the spirit and scope of the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for processing a bed frame structure, wherein the pipes are cut according to the design drawings; the cut pipes are positioned by tooling to prepare for welding; It is characterized in that The bed frame structure includes side beams on both sides and at least two cross beams connecting the side beams on both sides. The side beams are hollow, and the inner and outer contours of the cross section are both hollow rectangles. The outer contour of the cross beam cross section is rectangular. On the side where the side beams are connected to the cross beams, two groups of through holes are provided corresponding to the installation position of one end of each cross beam. Each group includes two through holes forming a strain bridge therebetween. The two strain bridges are respectively located on both sides of one end of the cross beam and serve as spot welding positions for the side beams and the cross beam. Processing methods include: A strain gauge is attached to the inner wall of the hollow cavity of the side beam at a position corresponding to the strain bridge; At both ends of the beam in the longitudinal direction, four-point spot welding is performed on the strain bridge to position the beam. After welding is completed, the positioning of the beam by the tooling is released; The data of each strain gauge is monitored, and when the data conditions are met, full welding is performed at the connection position between the side beam and the cross beam.

2. The method for processing a bed frame structure according to claim 1, characterized in that: The fully welded cladding area covers the strain bridge and the through hole.

3. The method for processing a bed frame structure according to claim 1, characterized in that: The strain gauge is adhered and fixed on the inner wall of the hollow cavity of the side beam.

4. The method for processing a bed frame structure according to claim 1, characterized in that: The through holes are waist-shaped holes, and the length direction of the waist-shaped holes is arranged along the length direction of the side beams.

5. The method for processing a bed frame structure according to claim 1, characterized in that: The strain bridges on both sides of one end of the beam correspond to the center positions of the edge of the beam.

6. The method for processing a bed frame structure according to claim 1, characterized in that: The data conditions include: The monitoring values ​​of the four strain gauges corresponding to each of the beams are all within a first set range, and the variances between the four monitoring values ​​are within a second set range.

7. The method for processing a bed frame structure according to claim 1, characterized in that: The data conditions include: Within a set time range, the variance of the real-time data change rates of the four strain gauges is within a third set range.

8. The method for processing a bed frame structure according to claim 1, characterized in that: The tooling includes an object detection device, which performs detection at least before releasing the positioning of the tooling on the beam, and both releasing the positioning and full welding are performed when the detection result shows that there is no object close to the set range around the tooling.

9. The method for processing a bed frame structure according to claim 1, characterized in that: Compressed air is introduced into the side beam, and the compressed air circulation time covers the spot welding process and the data monitoring process of the strain gauge.

10. The method for processing a bed frame structure according to claim 9, characterized in that: The compressed air circulates in a vortex shape.

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