阅读说明：本技术 一种用于热塑性复合材料与轻质合金激光连接的可控渐进加载装夹设备和方法 (Controllable progressive loading clamping equipment and method for laser connection of thermoplastic composite material and light alloy ) 是由 占小红 卜珩倡 李云 王飞云 杨红艳 马婉萍 于 2019-11-13 设计创作，主要内容包括：本发明公开了一种用于热塑性复合材料与轻质合金激光连接的可控渐进加载装夹设备和方法；包括工作平台,固定系统,监测与反馈系统,控制中心,施压系统,和回型框架。其中工作平台用来承载装夹设备和热塑性复合材料；监测与反馈系统用于测量连接件表面所受到的压力并实时反馈给控制中心；控制中心根据预设递增压力曲线和实时压力信息给出命令；施压系统依据命令实时调整连接件表面的压力。本发明可以实时监测和调控连接件表面所受到的压力,可控渐进加载施加给连接件表面的压力,促进界面处树脂的流动和扩散,增大有效连接面积,提高热塑性复合材料与轻质合金的结合能力,确保获得高质量的热塑性复合材料与轻质合金激光连接件。(The invention discloses controllable gradual loading clamping equipment and a method for laser connection of a thermoplastic composite material and a light alloy; comprises a working platform, a fixing system, a monitoring and feedback system, a control center, a pressure applying system and a clip frame. The working platform is used for bearing clamping equipment and thermoplastic composite materials; the monitoring and feedback system is used for measuring the pressure on the surface of the connecting piece and feeding back the pressure to the control center in real time; the control center gives commands according to a preset incremental pressure curve and real-time pressure information; the pressure applying system adjusts the pressure of the surface of the connecting piece in real time according to the command. The invention can monitor and regulate the pressure on the surface of the connecting piece in real time, can control and gradually load the pressure applied to the surface of the connecting piece, promotes the flow and diffusion of resin at the interface, increases the effective connecting area, improves the binding capacity of the thermoplastic composite material and the light alloy, and ensures that the high-quality thermoplastic composite material and light alloy laser connecting piece is obtained.)

1. A controllable gradual loading clamping device and method for laser connection of thermoplastic composite materials and light alloys are characterized in that: the device comprises a working platform, a fixing system, a monitoring and feedback system, a control center, a pressure applying system and a returning frame;

the working platform is used for bearing the clamping equipment and the thermoplastic composite material and is characterized in that a plurality of positioning holes for fixing the clamping equipment are formed in the working platform;

the fixing system is used for fixing the clamping equipment and the connecting piece and comprises a main fixing arm, an auxiliary fixing arm, a rotating rod, a limiting piece, a main clamping support and an auxiliary clamping support;

the monitoring and feedback system monitors the pressure on the surface of the connecting piece and transmits pressure information to the control center, and comprises a pressure sensor, and is characterized in that the pressure sensor is embedded into the pressing block, measures the pressure on the surface of the connecting piece and feeds the pressure information back to the control center in real time;

the control center is used for receiving the pressure information and giving a command according to a preset incremental pressure curve so as to control the pressure applying system to apply pressure, so that the pressure applied to the surface of the connecting piece reaches a preset value, and the pressure applying system is controlled to keep the pressure for a period of time after the connection is finished;

the pressure applying system adjusts the pressure applied to the surface of the connecting piece according to a command of the control center, and comprises a motor, a pressure lever, a lifting column and a pressure block, wherein the pressure applied is gradually increased according to a preset increasing pressure curve, so that the flowing and fusion of the molten resin at the interface are promoted, the pressure is maintained for a period of time after the connection is finished, and the interface fusion effect is improved;

the clip frame is used for bearing the fixing system and transmitting pressure, and laser can penetrate through the square hole in the middle of the clip frame and irradiate the surface of the connecting piece, so that the thermoplastic composite material and the light alloy are connected.

2. The controllable progressive loading clamping device for the laser connection of the thermoplastic composite material and the light alloy according to claim 1, characterized in that: the fixing system fixes the clamping equipment and the thermoplastic composite material on the working platform, a monitoring and feedback system in the clamping equipment detects the pressure on the surface of the connecting piece and transmits the pressure information to the control center, the control center gives a command based on the real-time pressure information and a preset incremental pressure curve, the pressure application system is controlled to apply pressure until the pressure on the surface of the connecting piece is ensured to reach a preset value, after the laser connection is completed, the pressure application system keeps the pressure for a period of time, the preset incremental pressure curve mainly comprises a linear incremental curve, a concave incremental curve, a convex rapid incremental curve and an S-shaped incremental curve.

3. The controllable progressive loading clamping device for the laser connection of the thermoplastic composite material and the light alloy according to claim 1, characterized in that: the fixing system is characterized in that a main fixing arm and an auxiliary fixing arm are connected with a clamping support through a rotating rod, the bottom of the main fixing arm is inserted into a positioning hole, the auxiliary fixing arm is connected with a clip-shaped frame, fixing of clamping equipment is achieved jointly, and meanwhile an initial pressure is applied to the surface of a connecting piece by the fixing system.

4. The controllable progressive loading clamping device for the laser connection of the thermoplastic composite material and the light alloy according to claim 1, characterized in that: in the pressure application system, the motor drives the lifting rod according to a command of the control center, so that the pressure of the pressing block on the surface of the connecting piece is controlled.

5. An operating method for the controlled progressive loading of thermoplastic composites in laser connection with light alloys, characterized in that it comprises the following steps:

the method comprises the following steps: presetting parameters such as incremental pressure curve types, initial pressure values, peak pressures, pressure maintaining time and the like, and inputting the parameters to a control center;

step two: placing the thermoplastic composite material and the light alloy on a working platform, installing clamping equipment, fixing the position of a connecting piece, and controlling a pressure rod to apply initial pressure to the surface of the connecting piece by a control center according to input parameters;

step three: starting laser connection, irradiating the surface of the light alloy by laser emitted by a laser, transmitting heat to the thermoplastic composite material, melting surface resin, and realizing the connection of the thermoplastic composite material and the light alloy by the flowing diffusion of the molten resin and the filling of an interface gap under the action of pressure;

step four: monitoring and feeding back pressure information, wherein in the connection process, a monitoring and feeding back system measures the pressure state borne by the surface of the connecting piece in real time and feeds back the measured information to a control center, when the pressure does not reach a preset pressure curve value, the control center controls a motor to drive a lifting rod, and the pressure value of a pressing block on the surface of the connecting piece is adjusted until the preset pressure curve value is reached;

step five: after laser connection is finished, in the cooling process of the connecting piece, the control center controls the pressure rod to maintain pressure for a period of time according to preset parameters to promote full fusion of resin at the interface, and controls the pressure rod to release pressure after pressure maintaining is finished;

step six: and finishing the process of connecting the thermoplastic composite material and the light alloy by laser, and disassembling the equipment.

6. The operating method for controlled progressive loading of thermoplastic composites with light alloy laser joining according to claim 5, characterized in that: the control center receives the connecting piece surface pressure state information transmitted by the monitoring and feedback system, and adjusts the pressure lever based on a preset incremental pressure curve, so that the pressure applied to the surface of the connecting piece conforms to the preset incremental curve, controllable progressive loading of the pressure applied to the surface of the connecting piece is realized, the diffusion and flow of resin at the interface are promoted, the effective combination area is increased, the pressure is maintained for a period of time after the connection is finished, and the interface fusion effect is improved.

Technical Field

The invention belongs to the field of laser connection, and particularly relates to controllable progressive loading clamping equipment and a method for laser connection of a thermoplastic composite material and a light alloy.

Background

The composite structure formed by connecting the thermoplastic composite material and the light alloy not only can exert the respective excellent performances of the two materials, but also can obviously reduce the weight of a component, and the composite structure has wide application in the fields of automobiles, aviation, aerospace and the like. The traditional technology for connecting the thermoplastic composite material and the light alloy mainly comprises adhesive bonding and mechanical riveting, and has the disadvantages of complex process, time consumption and low long-term effect. The laser connection technology is a new method for realizing the connection of the thermoplastic composite material and the light alloy, which is developed in recent years, has the advantages of high efficiency, small vibration stress, good processing flexibility and the like, and has good application prospect in the connection of the thermoplastic composite material and the light alloy.

In the process of connecting the thermoplastic composite material and the light alloy by laser, laser irradiates the surface of the light alloy, the metal surface absorbs laser energy, the generated heat is transferred to a connecting interface of the metal material and the thermoplastic composite material in a heat conduction mode, resin on the surface of the thermoplastic composite material is melted, and is diffused and fills an interface gap under the action of pressure, so that the thermoplastic composite material and the light alloy are effectively connected. In the process of connecting the thermoplastic composite material and the light alloy by laser, pressure is a key factor influencing the connection quality, and in the actual connection process, the acquisition of the high-quality thermoplastic composite material and the light alloy connecting piece is influenced by the inaccuracy of clamping and the instability of the surface pressure of the connecting piece. The controllable gradual loading pressure can effectively promote the flowing and diffusion of the interface resin and improve the effective combination area, thereby improving the quality of the laser connection joint of the thermoplastic composite material and the light alloy.

Disclosure of Invention

Aiming at the requirements and problems in the prior art, the invention provides the controllable progressive loading clamping equipment and the method for laser connection of the thermoplastic composite material and the light alloy, which can monitor and regulate the pressure on the surface of the connecting piece in real time, can controllably and progressively load the pressure on the surface of the connecting piece, promote the flowing and diffusion of resin at an interface, improve the binding capacity of the thermoplastic composite material and the light alloy, and ensure that the high-quality thermoplastic composite material and the light alloy laser connecting piece are obtained.

The invention is realized by the following technical scheme:

a controllable gradual loading clamping device and method for laser connection of thermoplastic composite materials and light alloys are characterized in that: the device comprises a working platform, a fixing system, a monitoring and feedback system, a control center, a pressing system and a returning frame.

The working platform is used for bearing the clamping equipment and the thermoplastic composite material and is characterized in that a plurality of positioning holes for fixing the clamping equipment are formed in the working platform;

the fixing system is used for fixing the clamping equipment and the connecting piece and comprises a main fixing arm, an auxiliary fixing arm, a rotating rod, a limiting piece, a main clamping support and an auxiliary clamping support. The main fixed arm and the auxiliary fixed arm are connected with the clamping support through the rotating rod, the bottom of the main fixed arm is inserted into the positioning hole, the auxiliary fixed arm is connected with the clip-shaped frame, the fixing of clamping equipment is realized together, and meanwhile, an initial pressure is applied to the surface of the connecting piece by the fixing system;

the monitoring and feedback system monitors the pressure on the surface of the connecting piece and transmits pressure information to the control center, and comprises a pressure sensor, wherein the pressure sensor is embedded into the pressing block, and is directly contacted with the surface of the connecting piece in the connecting process, so that the pressure on the surface of the connecting piece is measured in real time and the pressure information is fed back to the control center;

the control center is used for receiving pressure information and giving commands according to a preset incremental pressure curve so as to adjust the motor to control the lifting column to move, and therefore the pressure on the surface of the connecting piece is adjusted, and the pressure on the surface of the connecting piece reaches a preset value. After the connection process is finished, the pressure of the connecting piece is maintained for a period of time to promote fusion of resin at the interface, the connection quality is improved, and when the pressure maintaining time reaches a preset value, the control center adjusts the motor to control the lifting column to move, and the pressure applied to the surface of the connecting piece is released.

The pressure applying system adjusts the pressure applied to the surface of the connecting piece according to the command of the control center and comprises a motor, a pressure rod, a lifting column and a pressure block. The pressure bar is internally provided with a lifting column and a pressure block, and the lifting column is controlled by a motor and is directly connected with the pressure block. The motor adjusts the movement of the lifting column according to the command of the control center, thereby controlling the movement of the pressing block, so that the pressure applied to the surface of the connecting piece is changed. The middle part of the pressure lever is cylindrical, and the bottom is hemispherical. Directly in contact with the surface of the connecting piece is the bottom of the cylindrical compact. In the connection process, the pressure applying system gradually increases the pressure based on a preset incremental pressure curve according to a command of the control center, promotes the flowing and fusion of the molten resin at the interface, maintains the pressure for a period of time after the connection is completed, and improves the interface fusion effect. The preset increasing pressure curve mainly comprises a linear increasing curve, a concave increasing curve, a convex speed increasing curve and an S-shaped increasing curve.

The clip-shaped frame is used for bearing the fixing system and transmitting pressure, the upper surface of the clip-shaped frame is connected with the two auxiliary fixing arms, the lower surface of the clip-shaped frame is connected with the four pressure bars, and laser can penetrate through the square hole in the middle of the clip-shaped frame and irradiate on the surface of the connecting piece, so that the thermoplastic composite material and the light alloy are connected.

The operation method of controllable progressive loading applied to the laser connection of the thermoplastic composite material and the light alloy can be realized by the following steps:

the method comprises the following steps: parameters such as the type of an incremental pressure curve, an initial pressure value, a peak pressure, a pressure maintaining time and the like are preset and input to a control center. The type of the incremental pressure curve mainly comprises a linear incremental curve, a concave incremental curve, a convex speed incremental curve and an S-shaped incremental curve;

step two: placing the thermoplastic composite material and the light alloy on a working platform, installing clamping equipment, fixing the position of a connecting piece, and controlling a pressure rod to apply initial pressure to the surface of the connecting piece by a control center according to input parameters;

step three: starting laser connection, irradiating the surface of the light alloy by laser emitted by a laser, transmitting heat to the thermoplastic composite material, melting surface resin, flowing and diffusing the molten resin under the action of pressure, and filling an interface gap to finally realize the connection of the thermoplastic composite material and the light alloy;

step four: and monitoring and feeding back pressure information, wherein in the connection process, the monitoring and feeding back system measures the pressure state on the surface of the connecting piece in real time and feeds back the measured information to the control center, and when the pressure does not reach the preset pressure curve value, the control center controls the motor to drive the lifting rod, and adjusts the pressure value of the pressing block on the surface of the connecting piece until the preset pressure curve value is reached.

Step five: after laser connection is completed, in the cooling process of the connecting piece, the control center controls the pressure rod to maintain pressure for a period of time according to preset parameters, so that the resin at the interface is fully fused, and after pressure maintaining is completed, the control center controls the motor to drive the lifting rod, so that the pressure of the pressure block on the surface of the connecting piece is released.

Step six: and finishing the process of connecting the thermoplastic composite material and the light alloy by laser, and disassembling the equipment.

Compared with the prior art, the invention at least has the following advantages and effects:

compared with the traditional mechanical connection and bonding, the laser connection technology has the advantages of high welding speed, small welding heat input, short integral manufacturing period and high flexibility, and can realize digital and intelligent manufacturing;

the invention can monitor and regulate the pressure on the surface of the connecting piece in real time, can control gradual loading to apply uniform pressure on the surface of the connecting piece, promotes the flow and diffusion of resin at the interface, increases the effective connecting area, improves the binding capacity of the thermoplastic composite material and the light alloy, and ensures that a high-quality thermoplastic composite material and light alloy laser connecting piece is obtained;

the method defines the pressure maintaining time by user after the laser connection process is finished, promotes the fusion of resin at the interface, and improves the connection quality of the thermoplastic composite material and the light alloy;

the invention can accurately regulate and control the pressure state of the surface of the connecting piece in the connecting process, and can realize the stable manufacture of high-quality thermoplastic composite materials and light alloys by combining the optimization of process parameters;

the invention has the advantages of relatively simple structure, simple and easy technical means and has outstanding substantive progress compared with the prior art.

Drawings

FIG. 1 is a schematic diagram of the overall structure of a controllable progressive loading and clamping device for laser connection of thermoplastic composite materials and light alloy;

the numbering in fig. 1 indicates: 1-a working platform; 2, a motor; 3-a control center; 4-limiting sheet; 5-rotating the rod; 6-main card holder; 7-a main fixed arm; 8-auxiliary fixed wall; 9-auxiliary card holder; 10-a laser; 11-clip frame; 12-a pressure bar; 13-light weight alloys; 14-a backing plate; 15-positioning holes; 16-a thermoplastic composite; 17-a lifting column; 18-briquetting; 19-a pressure sensor; 20-a plunger housing; 21-laser scanning the track.

FIG. 2 is a partially enlarged view of a controllable progressive loading clamping device compression bar for laser connection of thermoplastic composite materials and light alloy.

FIG. 3 is a top view of the overall structure of a controllable progressive loading clamping device for laser connection of thermoplastic composite materials and light alloy.

Fig. 4 is a schematic diagram of a preset pressure increasing curve.

FIG. 5 is a flow chart of a method of operation for controlled progressive loading of thermoplastic composites in laser bonding with light weight alloys.

Detailed Description

The present invention will be described in further detail with reference to specific examples.