TWI738507B - Friction stir welding adapter having a static shaft shoulder system - Google Patents

Abstract

The present invention discloses a friction stir welding adapter having a static shaft shoulder system, which includes a head seat assembly, a friction stir welding tool holder and a static shaft shoulder assembly. The static shaft shoulder assembly has a pin hole and a shaft shoulder. A pin of the friction stir welding tool holder can be exposed from the pin hole. The friction stir welding tool holder forms a relative rotation relationship with the static shaft shoulder assembly during friction stir welding, so that it reduces the friction between the shaft shoulder and the workpiece surfaces and thus reduces the heat input during friction stir welding.

Description

Friction stir welding joint with static shoulder system

The invention relates to a friction stir welding joint with a static shaft shoulder system.

Friction stir welding technology is to pierce the blade between the two workpieces to rotate and rub the workpiece, and convert the mechanical kinetic energy of the blade into heat energy, so that the friction part of the two workpieces is plastically deformed by heating, so that the two workpieces are achieved by material stirring. The purpose of combining. Among them, how to provide a good static shoulder system is considered by those skilled in the art.

The main purpose of the present invention is to provide a friction stir welding joint with a static shoulder system.

In order to achieve the above and other objectives, the present invention provides a friction stir welding joint with a static shoulder system, which is installed on a machining shaft of a machine tool and used for friction stir welding of two workpieces. The friction stir welding Including the feed process, the welding process and the retreat process, the processing shaft has a rotating spindle and a spindle holder accommodating the rotating spindle, and the friction stir welding head includes: A headstock set for being fixedly connected to the spindle frame, and the headstock set has a headstock accommodating cavity; A friction stir welding tool holder accommodated in the accommodating cavity of the head seat and connected to the rotating spindle, the friction stir welding tool holder having a tool that is driven to rotate by the rotating spindle; A static shoulder assembly is arranged on the side of the headstock assembly away from the main shaft frame. The static shoulder assembly has a knife hole and a shoulder surrounding the knife hole. The shoulder assembly is used at least in the welding process Pressed against the two workpieces, and the static shoulder assembly allows at least a part of the tool to be exposed from the tool hole during the feed process and the welding process; Wherein, the friction stir welding tool handle forms a relative rotation relationship with the static shaft shoulder assembly during friction stir welding.

Since the static shaft shoulder assembly will not be driven by the rotating spindle during friction stir welding, the tool rotates alone during friction stir welding, and the shaft shoulder and the workpiece surface only slide relative to each other, so the friction between the shaft shoulder and the workpiece surface can be reduced , To reduce the heat input during friction stir welding.

Please refer to Figures 1-9, which is one embodiment of the friction stir welding joint (hereinafter referred to as the welding joint) of the present invention. The welding head can be installed on the machining shaft of the machine tool to perform friction stir welding on two workpieces. The machining shaft has a rotating spindle 1 and a spindle holder 2 that accommodates the rotating spindle 1, and the welding head includes a head seat group 200, a Static shoulder assembly 300, a friction stir welding tool holder 400 (hereinafter referred to as welding tool holder), a ball bearing bush 10, at least one ball bearing 20, at least one piston spring 30, at least one piston 40, at least one first guide post 50. At least one first linear bearing 60, at least one second guide post 70, at least one second linear bearing 80, a linear bearing fixing ring 90, a guide post fixing ring 100, a first heat insulation ring 110, a The second heat insulation ring 115 and a fluid parameter sensor 120.

The headstock assembly 200 is for fixing to the spindle frame 2, and a headstock accommodating cavity is enclosed inside the headstock assembly 200. The headstock assembly 200 includes a headstock 210, a headstock flange 220 and a piston fixing plate 230, and the headstock 210 is for fixing. Connected to the main shaft frame 2, a head block flange 220 is provided on the end of the head block 210 away from the main frame 2. For the convenience of assembly, the head base 210 can be further divided into an upper head base 211 and a lower head base 212. The upper head base 211 is provided with oil pressure pipes and cooling pipes. The lower head base 212 roughly defines the head base accommodating cavity. Side profile.

The static shoulder assembly 300 is arranged on the side of the headstock assembly 200 away from the main frame 2 so as to be relatively axially displaced. More specifically, the static shoulder assembly 300 is embedded in the headstock flange so as to be relatively axially displaced 220. The static shoulder assembly 300 has a knife hole 301, a shoulder 302 surrounding the knife hole 301, a gas nozzle disk 303 surrounding the shaft shoulder 302, and at least one gas nozzle 304 formed on the gas nozzle disk 303, wherein the shoulder 302 is more protruding than the gas nozzle plate 303 and can be pressed against the workpiece during friction stir welding. More specifically, the static shaft shoulder assembly 300 includes a tool retract pressure ring 310 and a static shoulder ring 320. The tool retract pressure ring 310 is provided on the side of the headstock assembly 200 away from the spindle frame 2, and the static shoulder ring 320 The knife hole 301, the shaft shoulder 302, the gas nozzle plate 303 and the gas nozzle 304 are formed in the static shaft shoulder ring 320, which is connected to the retracting pressure ring 310 but not directly contacting the head holder assembly 200.

The welding tool holder 400 is accommodated in the head holder accommodating cavity and connected to the rotating spindle 1, and has a tool holder cone 410, a torque transmission system 420, at least one tool holder spring 430, a tool 440 and a valve body 450. One end of the tool handle cone 410 is connected to the rotating spindle 1 and is provided with a tie rod bolt 411. The tool handle cone 410 has a cone accommodating cavity. The cone accommodating cavity has a spline sliding section 412 and an adjacent spline sliding section 412. The bushing accommodating section 413 of the connecting section 412 and a first keying groove 414 formed in the bushing accommodating section 413; for the purpose of cooling and handle control, a cone flow passage 415 is also formed in the handle cone 410, The cone runner 415 has a valve 416, and the cone runner 415 can be introduced into the gas flow during friction stir welding. The torque transmission system 420 includes a spline bushing 421, a first parallel key 422, a spline shaft 423, a spring seat 424, a second parallel key 425, and a tool locking ring 426. The spline bushing 421 is accommodated in the bushing accommodating section 413. The spline bushing 421 has a bushing outer surface 4211 and a bushing keying groove 4212 formed on the bushing outer surface 4211. The first parallel key 422 is keyed between the handle cone 410 and the spline bushing 421 and is accommodated in the first keying groove 414 and the bushing keying groove 4212 for connecting the handle cone 410 and the spline bushing. Torque is transmitted between the sleeves 421. The spline shaft 423 is axially slidably penetrated and keyed to the spline bushing 421. The spline shaft 423 has a spline head end 4231 that can slide axially on the spline sliding section 412 and a spline head end 4231. The spline tail end 4232 is not contained in the spline bushing 421 and a spline key connection groove 4233 is formed. The spring seat 424 has a spring seat accommodating cavity and a second key groove 4241 formed in the spring seat accommodating cavity, and the spring seat accommodating cavity is used for accommodating a part of the spline shaft 423. The second parallel key 425 is keyed between the spline shaft 423 and the spring seat 424 and is accommodated in the spline key groove 4233 and the second key groove 4241 for connecting the spline shaft 423 and the spring seat 424 Torque is transferred between. The tool locking ring 426 is fixed to the spring seat 424 and has a tool accommodating groove 4261. A first cooling channel 427 is also formed in the torque transmission system 420. The first cooling channel 427 extends through the spline shaft 423, the spring seat 424 and the tool locking ring 426, and the gas nozzle 304 of the static shoulder assembly 300 It is connected to the first cooling channel 427. The handle spring 430 is provided between the handle cone 410 and the spring seat 424, and is mainly used to provide forge force required for friction stir welding. The cutter 440 is disposed in the cutter accommodating groove 4261 and has a processing end protruding from the cutter accommodating groove 4261, and a part of the cutter 440 can protrude from the cutter hole 301 of the static shoulder assembly 300. Through the torque transmission system 420, the torque can be transmitted from the tool holder cone 410 to the tool 440, while allowing the spline shaft 423, the spring seat 424, the tool locking ring 426 and the tool 440 to be axially displaced relative to the tool holder cone 410.

The valve body 450 is arranged on the spline shaft 423 and is linked with the cutter 440 to selectively seal the valve 416; when the valve body 450 closes the valve 416, the cone flow passage 415 and the first cooling flow passage 427 cannot communicate with each other; When the valve 416 is not closed by the body 450, the cone runner 415 is connected to the first cooling runner 427, so that the gas flow can sequentially flow through the cone runner 415, the first cooling runner 427 and be ejected from the gas nozzle 304 The fluid parameter sensor 120 is used to sense the change of the fluid parameter of the gas flow in the flow channel, so as to achieve the purpose of cooling and tool control. The detailed principle will be described later. The fluid parameter sensor 120 can be located at any position that can sense the fluid parameters of the gas flow, for example, it can be located in the cone flow channel, the first cooling flow channel, or even in the gas flow channel inside the machining shaft upstream of the cone flow channel. , As long as the change of the fluid parameter of the gas flow can be sensed, and the fluid parameter can be air pressure and/or flow.

The ball bearing bushing 10 is arranged in the accommodating cavity of the head seat, and the ball bearing 20 is arranged between the ball bearing bushing 10 and the welding tool holder 400 to transmit force between the two. More specifically, a ball bearing accommodating cavity is formed between the ball bearing bushing 10 and the spring seat 424, and the ball bearing 20 is arranged in the ball bearing accommodating cavity for transmission between the ball bearing bushing 10 and the spring seat 424 The force, for example, transmits the axial upsetting force generated by the compression of the handle spring 430.

The piston 40 is arranged between the head block 200 and the static shoulder assembly 300. The length of the piston 40 in the axial direction of the welding tool holder 400 is variable, thereby allowing the static shoulder assembly 400 to be axially displaced relative to the welding tool holder 400, and The shoulder 302 is allowed to press against the workpiece. More specifically, one end of the piston 40 is arranged on the piston fixing disc 230 and connected with the hydraulic pipeline of the upper part 211 of the head base, and the axial length is changed by the hydraulic drive, and the other end of the piston 40 is arranged on the retracting pressure ring 310 .

The number of the first guide post 50 and the first linear bearing 60 are the same. The first guide post 50 extends in the axial direction and penetrates the first linear bearing 60. The first guide post 50 is connected to the head base 210 and the head base. Between the flanges 220, it is used to transfer the strength of the welding head to the spindle frame 2 through the head base 210 during friction stir welding.

The number of the second guide post 70 is the same as that of the second linear bearing 80. The second guide post 70 extends in the axial direction and passes through the second linear bearing 80. The second guide post 70 is connected to the guide post locating ring 100 and the static shaft shoulder. Between the assembly 300, the second guide post 70 and the second linear bearing 80 are arranged to allow the static shoulder assembly 300 to move smoothly in the axial direction. The guide post positioning ring 100 can be used to locate the second guide post, and the second It can be used to limit the stroke of the 300 axial displacement of the static shaft shoulder assembly, and has a stroke limit protection function.

The linear bearing fixing ring 90 has at least one first bearing hole 91, at least one second bearing hole 92 and a piston through hole 93. The linear bearing fixing ring 90 is fixed on the periphery of the ball bearing bush 10 for positioning the first and second linear bearings. The bearings 60 and 80 also transmit the force. The first linear bearing 60 is disposed in the first bearing hole 91, the second linear bearing 80 is disposed in the second bearing hole 92, and the piston 40 penetrates through the piston through hole 93. The piston spring 30 is arranged between the piston 40 and the linear bearing fixing ring 90 to push the static shoulder assembly 300 to the direction of the machining axis when the piston 40 is not working. Among them, the lateral force and lateral force borne by the tool during welding can be transmitted to the first and second linear bearings 60, 80, and the first and second guide posts 50, 70 through the ball bearing 20 and the ball bearing bushing 10, Then it is transmitted to the main shaft frame 2 through the head flange 220 and the head 210, so as to protect the torque transmission system and avoid damage.

The first heat insulation ring 110 is provided between the retracting pressure ring 310 and the static shoulder ring 320, the second heat insulation ring 115 is provided between the retracting pressure ring 310 and the ball bearing bushing 10, and the first and second partitions The thermal conductivity of the heat rings 110 and 115 is lower than the thermal conductivity of the retracting pressure ring 310, the static shoulder ring 320, and the ball bearing bushing 10, so as to reduce the transfer of heat energy to the inside of the welding joint. The first and second heat insulation rings 110 and 115 can form a good heat insulation system to avoid overheating and damage of bearing-related components. In addition, there is a second cooling channel 95 between the linear bearing fixing ring 90 and the ball bearing bushing 10, that is, the second cooling channel 95 surrounds the outer periphery of the ball bearing bushing 10; that is, The first and second cooling channels constitute a cooling system, which can also be used to avoid overheating and damage to bearing-related components.

There is a static shoulder system in the above welding head. Since the static shoulder assembly 300 will not be driven to rotate by the rotating spindle 1 during friction stir welding, the tool 440 rotates alone during friction stir welding, and the shoulder 302 and the surface of the workpiece only slide relatively, so the shoulder and the workpiece surface can be reduced. Friction with the surface of the workpiece, reducing the heat input during friction stir welding.

There is a retracting system in the above welding head. Generally speaking, friction stir welding includes an infeed process, a welding process and an exit process; the tool 440 can be exposed from the knife hole 301 of the static shoulder ring 320 during the infeed process and the welding process and begin to weld the workpiece. The piston spring 30 will pull the retract pressure ring 310 upward and use the second guide post 70 and the second linear bearing 80 to allow the static shoulder ring 320 to not rotate but to slide up and down axially; during the retracting process, the machining axis starts Away from the workpiece, the tool 440 is driven to exit the workpiece. At this time, if the shoulder does not press against the workpiece, an exit hole will be formed at the position where the tool 440 exits the workpiece after the tool is withdrawn. The exit hole needs to be repaired later. , Or the part where the exit hole needs to be removed. Since the present invention is provided with the piston 40, the piston 40 can be driven by hydraulic pressure to start working during the retracting process, so that the shoulder 302 of the static shoulder ring 320 keeps pressing against the workpiece when the tool 440 retracts, and this action It can ensure that no exit holes are generated on the surface of the workpiece after the tool is retracted, thereby improving the quality of welding.

There is an upsetting force transmission system in the above-mentioned welding joint. During welding, the tip of the cutter 440 pierces the workpiece, and the handle spring 430 is compressed to provide the upsetting force required for welding. The size of the upsetting force can be controlled by the amount of compression of the handle spring 430. Since the torque transmission system of the present invention allows the tool 440 to move up and down in the axial direction, even if the surface of the workpiece is not flat, the tool 440 and the shoulder 302 can follow the surface of the workpiece well, and because the upsetting force is caused by the tool handle spring 430 Provided, therefore, the elastic force of the handle spring 430 will only slightly change when the tool follows the surface of the workpiece, without causing a huge change or disappearance of the upsetting force, thereby overcoming the problem that the uneven surface of the workpiece affects the welding quality.

There is a gas valve switch system in the above welding head. The present invention has a valve body 450 linked with the cutter 440. Therefore, when the tip of the cutter 440 pierces the workpiece and retracts axially, the valve body 450 leaves the original position and no longer closes the valve 416, and the valve body 450 and the valve 416 are opposed to each other. When the position is changed, the pressure and flow rate of the gas flow through the valve 416 will change accordingly, so that at least one of the first cooling flow channel, the cone flow channel, and even the flow channel upstream of the cone flow channel will have fluid parameter changes. The time fluid parameter sensor 120 can determine the position where the tip of the tool 440 penetrates the workpiece according to the changes in the sensed fluid parameter, and is used to adjust the axial displacement of the machining shaft, so that the compression of the toolholder spring 430 can be controlled, thereby controlling Upsetting force required for welding. In addition, since the gas flow will be ejected from the gas nozzle 304 toward the workpiece, when the axial distance between the gas nozzle plate 303 and the workpiece changes during the welding process, the pressure and flow rate of the gas flow through the gas nozzle 304 will also change. The fluid parameter changes in the first cooling channel can be sensed by the fluid parameter sensor 120. This method can also allow the control system to determine the depth of the knife.

In addition, due to the integration of the above functions, the welding head of the present invention can be clamped and arranged on the processing shaft in a modular manner. For example, when the numerical control machining center performs milling, the welding head module is not installed on the processing shaft; when friction stir welding is subsequently performed, the welding head of the present invention can be automatically clamped and exchanged in a modular manner. The function of automatic mold change for friction stir welding.

1: Rotate the main shaft 2: Spindle frame 10: Ball bearing bushing 20: Ball bearing 30: Piston spring 40: Piston 50: The first guide post 60: The first linear bearing 70: second guide post 80: The second linear bearing 90: Linear bearing retaining ring 91: The first bearing hole 92: second bearing hole 93: Piston piercing 95: second cooling runner 100: Guide post fixing ring 110: The first insulation ring 115: second insulation ring 120: fluid parameter sensor 200: head seat group 210: Head Block 211: The upper part of the headstock 212: The lower part of the headstock 220: Head flange 230: Piston fixed disk 300: Static shaft shoulder assembly 301: Knife Hole 302: Shaft shoulder 303: Gas Nozzle Disk 304: gas nozzle 310: Retraction pressure ring 320: static shaft shoulder ring 400: Friction stir welding knife handle 410: Knife Cone 411: tie rod bolt 412: Spline sliding section 413: Bushing accommodating section 414: The first key slot 415: Cone runner 416: Valve 420: Torque transmission system 421: Spline bushing 4211: Outer surface of bushing 4212: Bushing key groove 422: The first parallel key 423: Spline shaft 4231: Spline head end 4232: Spline end 4233: Spline key slot 424: spring seat 4241: Second keying groove 425: second parallel key 426: Tool Locking Ring 4261: Tool holding slot 427: first cooling runner 430: Knife Spring 440: Tool 450: valve body

Figure 1 is a perspective view of one embodiment of the friction stir welding joint of the present invention.

Figure 2 is a perspective view of one embodiment of the friction stir welding joint of the present invention from another angle.

Figure 3 is an exploded view of one embodiment of the friction stir welding joint of the present invention, which mainly shows the torque transmission system.

Figure 4 is another exploded view of one embodiment of the friction stir welding joint of the present invention, which mainly shows the static shoulder system.

Figure 5 is another exploded view of one embodiment of the friction stir welding joint of the present invention, which mainly shows the piston, the first guide post and the second guide post, the friction stir welding tool holder and some components are omitted and not shown.

Figure 6 is a schematic cross-sectional view of one embodiment of the friction stir welding joint of the present invention.

Figure 7 is a schematic cross-sectional view from another angle of one embodiment of the friction stir welding joint of the present invention.

Figure 8 is a schematic cross-sectional view of the welding process of one embodiment of the friction stir welding joint of the present invention.

Figure 9 is a schematic cross-sectional view of the retracting process of one embodiment of the friction stir welding joint of the present invention.

110: The first insulation ring

115: second insulation ring

200: head seat group

300: Static shaft shoulder assembly

301: Knife Hole

302: Shaft shoulder

303: Gas Nozzle Disk

304: gas nozzle

310: Retraction pressure ring

320: static shaft shoulder ring

400: Friction stir welding knife handle

Claims (4)

A friction stir welding head with a static shoulder system, which is installed on a processing shaft of a machine tool and used for friction stir welding of two workpieces. The friction stir welding includes a knife-in process, a welding process, and a knife-out process, The machining shaft has a rotating main shaft and a main shaft holder for accommodating the rotating main shaft. The friction stir welding head includes: a head holder group for being fixed to the main shaft holder, the head holder group having a head holder accommodating cavity; and a friction stir welding head. The stir welding tool holder is accommodated in the head holder accommodating cavity and connected to the rotating spindle. The friction stir welding tool holder has a tool that is driven to rotate by the rotating spindle; a static shoulder assembly is arranged in the head holder assembly. On the side far away from the main frame, the static shoulder assembly has a knife hole and a shoulder surrounding the knife hole. The shoulder is at least used to press against the two workpieces during the welding process. The configuration allows at least a part of the tool to be exposed from the tool hole during the feeding process and the welding process; wherein the friction stir welding toolholder forms a relative rotation relationship with the static shaft shoulder assembly during friction stir welding; wherein , The static shaft shoulder assembly can be axially displaced relative to the friction stir welding tool holder during the retracting process to keep pressed against the two workpieces. The friction stir welding joint with static shoulder system according to claim 1, wherein the head base group includes a head base and a head base flange, the head base is fixed to the main shaft frame, and the head base flange is arranged on the The head base is away from one end of the main shaft frame, and the static shaft shoulder assembly is embedded in the flange of the head base. According to claim 1 or 2, the friction stir welding joint with a static shoulder system further includes a ball bearing bush and at least one ball bearing. The ball bearing bush is arranged in the accommodating cavity of the head seat, and the ball bearing is arranged Between the ball bearing bush and the friction stir welding tool handle. According to claim 3, the friction stir welding joint with a static shoulder system further includes at least one first guide post and at least one first linear bearing, and the number of the first guide post and the first linear bearing are the same, The first guide post extends in the axial direction and penetrates the first linear bearing, the first guide post is connected between the head base and the head base flange, and the first linear bearing is provided on the ball bearing Between the bush and the head seat.

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