Ultrasonic welding and online detection integrated flexible actuator

Abstract

The invention relates to the technical field of ultrasonic welding, in particular to an ultrasonic welding and online detection integrated flexible actuator which comprises a space movement device, a workbench and an end effector. The end effector comprises a parallel flexible mechanism, an ultrasonic welding machine installed at the tail end of the parallel flexible mechanism, a flattening device located at the front end of the ultrasonic welding machine in the welding direction, a consolidation device located at the rear end of the ultrasonic welding machine and a detection device located at the rear end of the consolidation device. Each of the flattening device and the consolidation device comprises a plurality of pressing columns which are flexibly arranged and are used for uniformly applying pressure to the workpiece; on-line real-time detection can be carried out, when a welding defect is found, the defect position can be returned to carry out repeated welding and detection, the welding and detection efficiency can be greatly improved, a parallel flexible mechanism is utilized, a welding head is in complete contact with a workpiece, the welding quality is greatly improved, and the repeated welding problem is prevented.

Description

Technical Field

[0001] The present invention relates to the technical field of ultrasonic welding, and in particular to an integrated flexible actuator for ultrasonic welding and online detection. Background Art

[0002] Existing ultrasonic welding mainly includes spot welding and continuous welding. However, after welding, the workpiece must be removed from the workbench and then subjected to non-destructive testing to determine whether the workpiece is well welded. If defects are found during this process, the workpiece must be re-clamped and re-positioned, and then the welding is repeated.

[0003] At the same time, since the ultrasonic welding process requires the welding head to be in close contact with the workpiece, if the contact is not close, it will cause a large number of welding defects during the welding process. However, due to the existence of mechanical errors, it is difficult to make the welding head completely contact the workpiece, which leads to large defects in the workpiece after welding.

[0004] In summary, the existing ultrasonic welding defects are:

[0005] 1. It is impossible to perform online real-time detection. The workpiece must be repeatedly removed for detection, then clamped, re-welded, and then tested in a vicious cycle, which is time-consuming and laborious.

[0006] 2. The existing ultrasonic welding has mechanical errors that make it impossible for the welding head and the workpiece to fit tightly together, resulting in welding defects.

[0007] 3. The existing welding equipment consolidation device can only use rolling consolidation when welding curved surfaces. Rolling consolidation is line-surface contact, resulting in poor final forming effect of the workpiece. Summary of the invention

[0008] The technical problem to be solved by the present invention is: in order to solve the problem that ultrasonic welding in the prior art cannot detect welding defects in real time and repeat welding according to the location of the defects, and the welding head and the workpiece cannot be in close contact during welding, an integrated flexible actuator for ultrasonic welding and online detection is provided.

[0009] In order to solve the above technical problems, the present invention adopts the following technical solution: an ultrasonic welding and online detection integrated flexible actuator, comprising:

[0010] Space motion device;

[0011] A workbench, used to carry workpieces;

[0012] and an end effector, which is mounted at the end of the space motion device and is used to follow the movement of the space motion device to perform welding on the workpiece on the workbench;

[0013] The end effector includes a parallel flexible mechanism, an ultrasonic welder installed at the end of the parallel flexible mechanism, a flattening device located at the front end of the ultrasonic welder along the welding direction to pre-press the workpiece, a consolidation device located at the rear end of the ultrasonic welder to maintain pressure on the workpiece, and a detection device located at the rear end of the consolidation device, and the flattening device and the consolidation device both include a plurality of flexibly arranged pressure columns for applying uniform pressure to the workpiece.

[0014] Furthermore, the parallel flexible mechanism includes a fixed platform connected to the spatial motion device, a moving platform spaced apart from the fixed platform, and a plurality of welding cylinders rotatably connected therebetween.

[0015] Furthermore, the flattening device and the consolidation device both include a pressure block for installing a pressure column, the pressure block is provided with an upper chamber and a lower chamber which are interconnected, and the lower chamber includes a plurality of diversion chambers which are partitioned, the plurality of diversion chambers correspond one-to-one to the pressure columns, and each pressure column is slidably installed inside the corresponding diversion chamber.

[0016] Furthermore, the pressure column includes a rod body and a pressure head fixed at the bottom of the rod body, and the pressure surface of the pressure head is an arc-shaped structure.

[0017] Furthermore, the detection device includes a detection cylinder, a connecting block connected to the output end of the detection cylinder, and a detection head hinged to the connecting block. The detection head includes an ultrasonic generator and a receiver, and is provided with a water inlet, a water leakage hole, and an air outlet for drying the workpiece.

[0018] Furthermore, the flattening device and the consolidation device also include a mounting plate, a pushing cylinder mounted on the mounting plate, and a transition block connected between the pushing cylinder and the pressing block, and the pressing block and the transition block are hingedly arranged.

[0019] Furthermore, the transition block has a pushing limit surface for limiting the rotation range of the pressing block, and the connecting block has a detection limit surface for limiting the rotation range of the detection head.

[0020] Furthermore, the consolidation device also includes an air outlet arranged on the transition block to cool the workpiece.

[0021] Furthermore, a rotary joint is provided between one end of the welding cylinder and the fixed platform, and a ball joint is provided between the other end of the welding cylinder and the movable platform.

[0022] Furthermore, a lower limit portion is formed between the pressure head and the rod body, an upper limit portion is formed on the top of the rod body, and the pressure block has a limit step for abutting against the upper limit portion and the lower limit portion.

[0023] Beneficial effects of the present invention:

[0024] 1. The present invention can perform online real-time detection. When welding defects are found, the defective position will be returned to for repeated welding and detection, which can greatly improve the welding and detection efficiency;

[0025] 2. The present invention adopts a parallel flexible mechanism to make the welding head fully contact with the workpiece, greatly improving the welding quality and preventing the occurrence of repeated welding problems;

[0026] 3. This patent adopts multiple line-surface contacts as consolidation and flattening, and the device can follow the shape of the workpiece for profiling, so that the force on the workpiece is more uniform and reasonable, and the forming effect is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0028] Figure 1 is a three-dimensional schematic diagram of the present invention;

[0029] Figure 2 It is a three-dimensional schematic diagram of the end effector from the first perspective;

[0030] Figure 3 is a three-dimensional schematic diagram of the second perspective of the end effector;

[0031] Figure 4 is the front view of the end effector;

[0032] Figure 5 It is a structural diagram of a parallel flexible mechanism;

[0033] Figure 6 is a schematic diagram of the structure of the flattening device;

[0034] Figure 7 It is a schematic diagram of the structure of the consolidation device and the detection device;

[0035] Figure 8 is a three-dimensional schematic diagram of the briquette;

[0036] Fig. 9 is a cross-sectional view of the pressing block in a first direction;

[0037] Fig.10 is a cross-sectional view of the pressing block in the second direction;

[0038] Fig.11 This is a schematic diagram of the cooperation between the pressure column and the workpiece with large curvature;

[0039] Fig.12 It is a schematic diagram of the structure of the detection head.

[0040] In the figure:

[0041] 1. Space motion device;

[0042] 2. Workbench;

[0043] 3. End effector; 301. Parallel flexible mechanism; 3011. Fixed platform; 3012. Moving platform; 3013. Welding cylinder; 3014. Rotary hinge; 3015. Ball joint; 302. Ultrasonic welder; 303. Flattening device; 304. Consolidation device; 3041. Pressing column; 3041a. Rod; 3041b. Pressing head; 3041c. Lower limiter; 3041 d, upper limit part; 3042, pressure block; 3043, upper chamber; 3044, lower chamber; 3045, push cylinder; 3046, transition block; 3047, air outlet; 3048, air inlet; 305, detection device; 3051, detection cylinder; 3052, connection block; 3053, detection head; 3054, water inlet; 3055, water leakage hole; 3056, air outlet;

[0044] 4. Workpiece. DETAILED DESCRIPTION

[0045] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams that illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention, and directions and references (e.g., up, down, left, right, etc.) may only be used to help describe the features in the drawings. Therefore, the following specific embodiments are not to be taken in a limiting sense, and the scope of the subject matter claimed is limited only by the attached claims and their equivalents.

[0046] like Figure 1 As shown, an ultrasonic welding and online detection integrated flexible actuator comprises:

[0047] The spatial motion device 1 may be a robotic arm, a truss manipulator, an articulated robot, a gantry mechanism, a parallel mechanism, a virtual axis, etc., and its end can move freely in space, and the degrees of freedom include three spatial translation degrees of freedom and three spatial rotation degrees of freedom;

[0048] A workbench 2, used for carrying a workpiece 4, which is located within the motion range of the spatial motion device 1;

[0049] and an end effector 3, which is installed at the end of the spatial motion device 1 and is used to follow the movement of the spatial motion device 1 to perform welding on the workpiece 4 on the workbench 2;

[0050] like Figure 2-Figure 4As shown, the end effector 3 includes a parallel flexible mechanism 301, an ultrasonic welder 302 installed at the end of the parallel flexible mechanism 301, a flattening device 303 located at the front end of the ultrasonic welder 302 along the welding direction to pre-press the workpiece, a consolidation device 304 located at the rear end of the ultrasonic welder 302 to maintain the pressure on the workpiece, and a detection device 305 located at the rear end of the consolidation device 304, that is, along the ultrasonic welding direction, the flattening device 303 is located at the front end. Since the composite material will be heated and deformed during the ultrasonic welding process, it is necessary to install a flattening device 303 at the welding head to ensure the welding quality. The workpiece 4 is flattened in front to prevent warping and deformation, so a flattening device 303 is needed to pre-press the workpiece 4, followed by an ultrasonic welder 302, which generates high-frequency vibration and contacts with the workpiece 4 to generate viscoelastic heat to melt the thermoplastic composite matrix and adhere to achieve the welding effect, and then a consolidation device 304. Since ultrasonic continuous welding is a welding head passing through the workpiece 4, a pressure is actually required to keep the workpiece 4 under this pressure for a short period of time to make it adhere firmly. Finally, a detection device is used to detect the molding effect of the workpiece 4 after welding in real time, and feedback to the operator in the form of an image.

[0051] The flattening device 303 and the consolidation device 304 both include a plurality of flexibly arranged pressure columns 3041 that apply uniform pressure to the workpiece 4. Each pressure column 3041 applies equal pressure to the workpiece 4, and a plurality of pressure columns 3041 realize multiple line-surface contacts during consolidation and flattening. The plurality of flexibly arranged pressure columns 3041 can follow the shape of the workpiece 4 for contour profiling, thereby making the force on the workpiece 4 more uniform and reasonable, and greatly improving the forming effect.

[0052] During operation, the flattening device 303, the ultrasonic welder 302, the consolidation device 304, and the detection device 305 contact the workpiece 4 placed on the workbench 2 in sequence. First, the flattening device 303 pre-presses the workpiece 4 to flatten the workpiece 4 to prevent it from being deformed by heat. Then the welding head of the ultrasonic welder 302 implements welding. Then the consolidation device 304 maintains pressure on the workpiece 4 to make it firmly adhered. Finally, the detection device 305 performs online real-time detection. If a defect is detected, the detection device 305 will transmit the position and size range of the defect to the control system, and the control system will command the welding head to return to the position where the welding defect exists to repeat the welding.

[0053] In some examples, such as Figure 5As shown, the parallel flexible mechanism 301 includes a fixed platform 3011 connected to the spatial motion device 1, a moving platform 3012 spaced apart from the fixed platform 3011, and a plurality of welding cylinders 3013 rotatably connected therebetween. The number of welding cylinders 3013 may be three, four, etc., and this embodiment does not limit this. The plurality of welding cylinders 3013 are spaced apart circumferentially. Under the coupling action of this mechanism, the moving platform 3012 can have up and down translational freedom and rotational freedom relative to the fixed platform 3011. Since cylinder actuation is adopted instead of electric cylinder actuation, when the moving platform 3012 receives external force, the cylinder will contract, causing the position and posture of the moving platform 3012 relative to the fixed platform 3011 to change.

[0054] The ultrasonic welding machine 302 is installed and fixed on the moving platform 3012. When the welding head is not in close contact with the workpiece 4, the welding head will inevitably be subjected to a force that is not along the axis of the welding head. This force will force the welding head to change its posture relative to the fixed platform 3011. This change causes the cylinder to contract or extend, and eventually causes the moving platform 3012 to change its posture. Finally, the welding head will be in complete contact with the workpiece 4 before this change will stop. Therefore, this structure solves the defect that the welding head is not in close contact with the workpiece 4. At the same time, when several cylinders are activated at the same time, the welding head will move downward along its axial direction.

[0055] In some examples, such as Figure 6-Figure 9 As shown, the flattening device 303 and the consolidation device 304 both include a pressing block 3042 for installing a pressing column 3041, the pressing block 3042 is provided with an upper chamber 3043 and a lower chamber 3044 which are interconnected, and the lower chamber 3044 includes a plurality of flow dividing chambers which are separated and arranged, each flow dividing chamber has an equal cross-sectional area, a plurality of flow dividing chambers correspond to the pressing column 3041 one by one, and each pressure column 3041 is slidably installed inside the corresponding flow dividing chamber, the pressing column 3041 can reciprocate in the vertical direction in the flow dividing chamber under the action of the airflow, and it can seal the flow dividing chamber. The pressure block 3042 is sealed to prevent air leakage. An air inlet 3048 for communicating with the upper chamber 3043 is provided. The pressurized air flows into the upper chamber 3043 from the air inlet 3048, and then flows into each diversion chamber and drives the pressure column 3041 in each diversion chamber to move downward. Since the cross-sectional area of ​​each pressure column 3041 is equal, the pressure applied to the workpiece 4 is consistent. Moreover, since the airflow is compressible, when facing a workpiece 4 with a curvature, it can be contoured according to the shape of the workpiece 4, so that the force on the workpiece 4 is more uniform and reasonable, and the molding effect is greatly improved. Fig.11 shown.

[0056] In some examples, such as Fig. 9As shown, the pressure column 3041 includes a rod body 3041a and a pressure head 3041b fixed at the bottom of the rod body 3041a. The pressure surface of the pressure head 3041b is an arc-shaped structure. When facing a workpiece 4 with a curvature, the arc surface can always keep in contact with the workpiece 4.

[0057] In some examples, such as Figure 7 and Fig.12 As shown, the detection device 305 includes a detection cylinder 3051, a connection block 3052 connected to the output end of the detection cylinder 3051, and a detection head 3053 hinged to the connection block 3052. The detection cylinder 3051 is fixed on the static platform 3011 through a fixing plate, and a slide rail and slider combination is provided between the connection block 3052 and the fixing plate. Under the action of the detection cylinder 3051, the connection block 3052 can drive the detection head 3053 to move up and down;

[0058] The detection head 3053 includes an ultrasonic generator and a receiver, and is provided with a water inlet 3054, a water leakage hole 3055 and an air blowing port 3056 for drying the workpiece 4. The ultrasonic wave needs to be water coupled during the detection process. After water enters from the water inlet 3054, it is distributed to each water leakage hole 3055, which is coupled with the detection head 3053 to assist in detection. However, water is not needed after the detection is completed. The air blowing port 3056 can quickly evaporate the moisture to ensure the dryness of the workpiece 4.

[0059] In some examples, such as Figure 6 and Figure 7 As shown, the flattening device 303 and the consolidation device 304 also include a pushing cylinder 3045 and a transition block 3046 connected between the pushing cylinder 3045 and the pressing block 3042. In order to prevent the pressing block 3042 from interfering with or colliding with the workpiece 4 when welding a workpiece 4 with a large curvature, the pressing block 3042 and the transition block 3046 are hingedly arranged. The pushing cylinder 3045 is fixed on the static platform 3011 through a mounting plate. A slide rail and slider combination is also provided between the transition block 3046 and the mounting plate. Under the action of the pushing cylinder 3045, the transition block 3046 can drive the pressing block 3042 to slide up and down, and apply pressure to the workpiece 4 through the pressure column 3041. Since the consolidation device 304 and the detection device are located on the same side of the ultrasonic welder 302, the mounting plate of the consolidation device 304 and the fixing plate of the detection device 305 can be integrally formed.

[0060] In some examples, such as Figure 7 and Figure 8As shown, the transition block 3046 has a push-limiting surface for limiting the rotation range of the pressing block 3042. When the pressing block 3042 rotates around the transition block 3046, the push-limiting surface can ensure that the rotation angle of the pressing block 3042 is within a certain range. The push-limiting surface is the bottom surface of the pressing block 3042. In order to improve the welding effect, the flattening device 303 and the consolidation device 304 distributed on both sides of the welding head should be as close to the welding head as possible. Therefore, the transition block 3046 of the flattening device 303 and the transition block 3046 of the consolidation device 304 are bent toward the direction of the welding head.

[0061] like Figure 7 As shown, the connecting block 3052 has a detection limit surface for limiting the rotation range of the detection head 3053. When the detection head 3053 rotates around the connecting block 3052, the detection limit surface can ensure that the rotation angle of the detection head 3053 is within a certain range. The detection limit surface is the bottom surface of the connecting block 3052.

[0062] In some examples, such as Figure 7 As shown, the consolidation device 304 also includes an air outlet 3047 arranged on the transition block 3046 to cool the workpiece 4. Since the temperature of the workpiece 4 is relatively high after welding, the air outlet 3047 can be set to quickly cool and shape it, that is, the flattening device 302 and the consolidation device 304 have roughly the same structure, except that the consolidation device 304 has the air outlet 3047.

[0063] In some examples, such as Figure 5 As shown, a rotary joint 3014 is provided between one end of the cylinder and the fixed platform 3011, and a Hooke's joint 3015 or a ball joint is provided between the other end of the cylinder and the moving platform 3012, so that the moving platform 3012 has two rotational degrees of freedom.

[0064] In some examples, such as Fig.10 As shown, a lower limit portion 3041c is formed between the pressure head 3041b and the rod body 3041a, an upper limit portion 3041d is formed on the top of the rod body 3041a, and the pressure block 3042 has a limit step for abutting against the upper limit portion 3041d and the lower limit portion 3041c. When the upper limit portion 3041d abuts against the limit step, the lower limit position of the pressure column 3041 can be limited, and when the lower limit portion 3041c abuts against the limit step, the upper limit position of the pressure column 3041 can be limited.

[0065] Working principle:

[0066] During operation, first, the spatial motion device 1 drives the end effector 3 to move above the workpiece 4, the welding cylinder 3013 drives the ultrasonic welder 302, the flattening device 303 and the pushing cylinder 3045 of the consolidation device 304 drive the pressure column 3041, and the detection cylinder 3051 drives the detection head 3053 to press the workpiece 4 synchronously, then the pressure block 3042 of the flattening device 303 and the consolidation device 304 is ventilated, and the pressurized air flows into the upper chamber 3043 from the air inlet 3048, and then flows into each diversion chamber and drives the pressure column 3041 in each diversion chamber to move downward, according to the external shape of the workpiece 4. The shape is imitated to apply uniform pressure to the workpiece 4. After the workpiece 4 is flattened, the ultrasonic welder 302 is in full contact with the workpiece 4 under the action of the parallel flexible mechanism 301 to implement welding, and then the pressure column 3041 of the consolidation device 304 applies uniform pressure to the workpiece 4 again to make the workpiece 4 adhere firmly. At the same time, the air outlet 3047 cools the workpiece 4. Finally, the detection head 3053 implements detection. At the same time, water enters from the water inlet 3054 and is distributed to each leakage hole 3055, which is coupled with the detection head 3053 for detection. After the detection is completed, the air outlet 3056 can quickly evaporate the water to ensure the dryness of the workpiece 4.

[0067] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. An integrated flexible actuator for ultrasonic welding and online detection, characterized in that: include: Space motion device (1); A workbench (2) for carrying a workpiece (4); and an end effector (3), which is mounted at the end of the spatial motion device (1) and is used to follow the movement of the spatial motion device (1) to perform welding on a workpiece (4) on a workbench (2); The end effector (3) comprises a parallel flexible mechanism (301), an ultrasonic welder (302) installed at the end of the parallel flexible mechanism (301), a flattening device (303) located at the front end of the ultrasonic welder (302) along the welding direction to pre-press the workpiece, a consolidation device (304) located at the rear end of the ultrasonic welder (302) to maintain pressure on the workpiece, and a detection device (305) located at the rear end of the consolidation device (304), and the flattening device (303) and the consolidation device (304) both comprise a plurality of flexibly arranged pressure columns (3041) used to uniformly apply pressure to the workpiece (4).

2. The integrated flexible actuator for ultrasonic welding and online detection according to claim 1 is characterized in that: The parallel flexible mechanism (301) comprises a fixed platform (3011) connected to the spatial motion device (1), a movable platform (3012) spaced apart from the fixed platform (3011), and a plurality of welding cylinders (3013) rotatably connected therebetween.

3. The integrated flexible actuator for ultrasonic welding and online detection according to claim 1 is characterized in that: The flattening device (303) and the consolidation device (304) both include a pressing block (3042) for installing a pressing column (3041), and an upper chamber (3043) and a lower chamber (3044) that are interconnected are formed inside the pressing block (3042), and the lower chamber (3044) includes a plurality of diversion chambers that are separated and arranged, and the plurality of diversion chambers correspond one-to-one to the pressing columns (3041), and each pressing column (3041) is slidably installed in the corresponding diversion chamber.

4. The integrated flexible actuator for ultrasonic welding and online detection according to claim 1 is characterized in that: The pressure column (3041) comprises a rod body (3041a) and a pressure head (3041b) fixed at the bottom of the rod body (3041a), and the pressure surface of the pressure head (3041b) is an arc-shaped structure.

5. The integrated flexible actuator for ultrasonic welding and online detection according to claim 3 is characterized in that: The detection device (305) comprises a detection cylinder (3051), a connection block (3052) connected to the output end of the detection cylinder (3051), and a detection head (3053) hinged to the connection block (3052); the detection head (3053) comprises an ultrasonic generator and a receiver, and is provided with a water inlet (3054), a water leakage hole (3055), and an air outlet (3056) for drying the workpiece (4).

6. The integrated flexible actuator for ultrasonic welding and online detection according to claim 5 is characterized in that: The flattening device (303) and the consolidating device (304) further include a pushing cylinder (3045) and a transition block (3046) connected between the pushing cylinder (3045) and the pressing block (3042), and the pressing block (3042) and the transition block (3046) are hingedly arranged.

7. The integrated flexible actuator for ultrasonic welding and online detection according to claim 6 is characterized in that: The transition block (3046) has a pushing limit surface for limiting the rotation range of the pressing block (3042), and the connecting block (3052) has a detection limit surface for limiting the rotation range of the detection head (3053).

8. The integrated flexible actuator for ultrasonic welding and online detection according to claim 6 is characterized in that: The consolidation device (304) further comprises an air outlet (3047) arranged on the transition block (3046) for cooling the workpiece (4).

9. The integrated flexible actuator for ultrasonic welding and online detection according to claim 1 is characterized in that: A rotary hinge (3014) is provided between one end of the welding cylinder (3013) and the fixed platform (3011), and a Hooke's hinge (3015) is provided between the other end of the welding cylinder (3013) and the moving platform (3012).

10. The integrated flexible actuator for ultrasonic welding and online detection according to claim 4 is characterized in that: A lower limit portion (3041c) is formed between the pressure head (3041b) and the rod body (3041a), an upper limit portion (3041d) is formed on the top of the rod body (3041a), and the pressure block (3042) has a limit step for abutting against the upper limit portion (3041d) and the lower limit portion (3041c).

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