[0022] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.
[0023] The automatic flame brazing machine for copper-aluminum welding of micro-channel heat exchangers in the embodiment of the present invention is a six-station turntable automatic flame brazing machine, including a feeding station, a detection station, a welding station, two A cooling station and a blanking station.
[0024] At the loading station, the workpiece on the pre-loading tool 1 can be pushed into place, the protective cover is put on, and solder paste is applied to the welding place. The operation box 2 can use the operation box with button touch screen, which can realize the saving of parameters of various models, quick selection and convenient operation.
[0025] At the detection station, a detection part 3 for the presence or absence of a protective plate and a detection part 4 for the presence or absence of a workpiece are provided. If it is detected that the protective plate is in place and there is a workpiece, it is pre-selected that the welding station can be welded; if there is no workpiece or the protective cover is not in place, it is pre-selected that the welding station cannot be welded. The purpose is to avoid air-fired welding malfunctions and to protect the workpiece from burning.
[0026] In the welding station, an electrical control system, a gas flow control system, a six-axis robot-controlled heating gun and an automatic wire feeding mechanism are provided. The gas flow control system includes a gas flow control box 9 , which provides a controllable and adjustable flame with a stable gas flow value for the heating gun component 14 . The electrical control system includes an electrical control box 10, which communicates with the touch screen operation box 2, and is used to control the six-axis robot 11, the gas flow control box 9, the automatic wire feeding mechanism, etc. to control the operation of the special plane. The six-axis robot 11 quickly controls the position of the heating gun component 14, and the teach pendant can quickly select the saved action program of the model. The automatic wire feeding mechanism provides quantitative welding wire for workpiece welding and cooperates with the heating gun component 14 to melt the welding wire in time to realize workpiece welding. The automatic wire feeding mechanism includes cutting parts 8 and 13 of the welding wire head. After the wire feeding is completed, the wire feeding nozzle returns to the initial position, and the cutting part cuts off the welding wire head. In order to ensure the quality of the welding wire of each wire feeding, ensure that the length of each welding wire is consistent and the position of the wire feeding is not deviated as much as possible.
[0027] In a preferred embodiment, the automatic wire feeding mechanism includes flexible wire feeding parts 7 and 12, and is provided with a photoelectric switch for detecting whether the welding wire is melted. When the welding wire is not melted, the wire feeding motor is controlled to suspend the rotation of the wire feeding until the welding wire is melted and then rotate the wire feeding. . This ensures that the position of each wire feeding is accurate, and the welding wire is quantitatively melted at the predetermined welding point position.
[0028] In another preferred embodiment, the welding station is provided with a position gap detection component 5 for measuring the small gap in the position of the welding point, and the six-axis robot automatically adjusts to a suitable heating position in response.
[0029] In another preferred embodiment, the welding station is provided with a temperature detection part 6, which detects the initial temperature value of the welding place of the workpiece and controls the automatic fine-tuning of the heating time.
[0030] In the two cooling stations, a first cooling part 15 and a second cooling part 16 are respectively provided. Speeding up the cooling makes the temperature of the workpiece lower than 50 degrees, which is not only suitable for the cooling process of flame brazing of this type of workpiece, but also ensures that the operator will not be scalded when cutting.
[0031] At the blanking station, open the protective cover of the tooling, and push the workpiece to the pre-cutting tooling 18 to realize the transition of the pre-cutting.
[0032] The six-station turntable 17 realizes that the six sets of tooling on the turntable rotate one station precisely at a timed interval, that is, 60 degrees.
[0033] The flame heating brazing operation process at the welding station is as follows: the temperature detection part 6 quickly detects the initial temperature of the copper pipe of the workpiece, and determines the increase or decrease of the heating time at the heating position of the copper pipe. The position gap detection part 5 detects the position deviation before and after the welding point, and the six-axis robot 11 refers to the position deviation detected by the position gap detection part 5. The heating gun part 14 is accurately and quickly moved to the accurate heating position, and the front and rear swing slightly, so that the copper tube can be used with the device. The fixed intensity fire value is more evenly heated within the specified time. After the heating time is reached, the six-axis robot 11 quickly moves the heating gun part 14 to the heating position of the aluminum base, and the heating gun part 14 swings back and forth slightly, so that the aluminum base can be compared with the set strong fire value within the specified time. Heat evenly. The heating time of the aluminum base is completed, and the flame is switched to a smaller flame. At the same time, the six-axis robot 11 quickly moves 14 the heating gun component to the vicinity of the solder filling, and the heating gun component 14 swings back and forth slightly to the set swing, flame size and time to heat up. After the heating is completed, the wire feeding cylinders of the 2 sets of flexible fixed-length wire feeding components 7 and 12 move to the front to make the wire feeding nozzle reach the proper position of the welding point; the wire feeding nozzle in-position switch signal makes the wire feeding motor feed wire at a certain speed until the completion The specified length of welding wire stops; during this period, if the welding wire does not melt, the corresponding photoelectric switch is activated, and the corresponding wire feeding motor immediately stops rotating and feeding the wire until the corresponding photoelectric switch is in the OFF state, and the corresponding wire feeding motor immediately rotates and feeds the wire again. After the wire feeding is completed, the wire feeding nozzle returns to the initial position, and the corresponding cutting parts 8 and 12 act to cut off the welding head once. After the heating gun part 14 is heated for a small set period of time to make the solder penetrate properly, the six-axis robot 11 quickly moves the heating gun part 14 to the initial position. After the welding process of the welding station is completed, the six-station turntable 17 waits for a predetermined time, and after the welding area has a predetermined time of natural cooling, the turntable rotates by one station. The workpiece that has been naturally cooled in advance is further accelerated to be cooled by the first cooling member 15 at the cooling station. Then use the second cooling part to continue to accelerate the cooling so that the temperature of the workpiece is lower than 50 degrees, which is not only suitable for the cooling process of flame brazing of this type of workpiece, but also ensures that the operator will not be burned when cutting the material.
[0034]The invention provides an advanced automatic flame brazing special machine for the copper-aluminum welding of various heat exchanger copper tubes and aluminum bases, which replaces the manual welding method and reduces the waste of poor manual welding. The stability of welding quality has been improved, and the first pass rate has reached more than 99%. The economic benefits of mass production with quality and quantity have been realized, and a new type of automation equipment has been developed for the emerging micro-channel field in the air-conditioning industry.
[0035] The above descriptions are only preferred implementations of the present invention, and the scope of protection of the present invention is not limited to the above-mentioned embodiments, and all technical solutions under the idea of the present invention belong to the scope of protection of the present invention. It should be pointed out that for those skilled in the art, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.
