JP2007216249A - Friction stir spot welding equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a friction stir spot welding equipment where a motor for driving a center pin is used for allowing a pin to frequently appear from the tip of a shoulder pin, a motor for stirring and the motor for driving a center pin are fixed to a welding driving side, and the center pin is easily and securely allowed to frequently appear. <P>SOLUTION: In the friction stir spot welding equipment, hollow parts 12, 22 are formed on a center pin shaft 11 and a shoulder pin shaft 21, respectively, the tip side of a screw shaft 41 for pressurization is inserted into the hollow part of the center pin shaft and the tip side of the center pin shaft is inserted into the hollow part of the shoulder pin shaft, respectively, with the screw shaft for pressurization as a driving shaft core, the center pin shaft is located in the outer circumference thereof and the shoulder pin shaft is located in the outer circumference of the center pin shaft, respectively, and a motor 5 for driving a center pin of progressing/retreating the center pin individually and the center pin shaft, and a motor 3 for stirring of rotating the shoulder pin shaft and the shoulder pin shaft are connected with transmission belts 51, 31, respectively. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention is a device for softening and agitating the object to be joined by frictional heat generated by the rotation of the center pin and the shoulder pin, and spot-joining the device. The agitating module rotates the shoulder pin in which the center pin is inserted. The present invention relates to a friction stir spot welding device comprising a motor and a pressurizing motor for driving the shoulder pin linearly, and a center pin protruding and retracting from the tip of the shoulder pin.

  2. Description of the Related Art Conventionally, an apparatus for spot welding by softening and agitating an object to be joined by frictional heat generated by the rotation of a center pin and a shoulder pin, wherein the agitating motor rotates the shoulder pin in which the center pin is inserted. And a pressurizing motor for linearly driving the shoulder pin, wherein the center pin protrudes from the tip of the shoulder pin, and a center pin from the shoulder pin is provided. The agitation mode is controlled so that the drive of the shoulder pin and the center pin is fixed to the main body of the joining device, and the movement of the center pin is controlled by reversing the rotation direction of the shoulder pin. In some cases, this is performed by output transmission from a motor and a pressurizing motor (for example, see Patent Document 1).

Japanese Patent No. 3505508

  By the way, in the above-mentioned conventional technology, since the center pin is protruded and projected at a constant level, the center pin pressure and the shoulder pin pressure cannot be individually adjusted. The center pin can not meet the center pin joining conditions that differ depending on the type, and the rotation direction of the shoulder pin is reversed when the center pin moves forward and backward. Since the temperature of the member to be joined decreases, it is difficult to obtain the joining conditions, and since the agitation motor and pressurization motor are fixed to the main body of the joining device, the spline is used for drive control of the shoulder pin and the center pin. There is a problem that the transmission path of each motor output becomes complicated accordingly.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a motor for driving a center pin in order to project and retract the pin from the tip of the shoulder pin. It is intended to provide a friction stir spot welding device that can easily and surely move the center pin in and out by fixing the agitating motor and the center pin driving motor to the joining drive side. .

  In order to achieve the above object, the friction stir spot welding device according to the present invention has a hollow portion formed in each of the center pin shaft and the shoulder pin shaft, and the tip side of the pressure screw shaft is formed in the hollow portion of the center pin shaft. Are inserted into the hollow part of the shoulder pin shaft, the tip side of the center pin shaft is inserted into the hollow portion of the shoulder pin shaft, the pressurizing screw shaft as the drive shaft core, the center pin shaft on the outer periphery, and the shoulder pin on the outer periphery of the center pin shaft Center pin driving motor and center pin shaft for moving the shaft individually and moving the center pin independently, and the stirring motor and shoulder pin shaft for rotating the shoulder pin shaft. Each of them is characterized by being connected by a transmission belt.

  In the friction stir spot welding device according to the present invention, the center pin driving motor and the center pin shaft for independently moving the center pin back and forth, and the stirring motor and the shoulder pin for rotating the shoulder pin shaft are provided. Since the shafts are connected by transmission belts, the center pin pressure and shoulder pin pressure can be individually adjusted to meet different center pin joining conditions depending on the type and thickness of the joining member. Since it is not necessary to reverse the direction of rotation of the shoulder pin when the center pin moves forward and backward, the temperature of the welded member is prevented from lowering and the joining conditions are easily set. Since the transmission of the output from the driving motor does not need to go through a complicated spline mechanism, it can be carried out with a simple transmission belt, so that the apparatus is simplified. In addition, the tip of the pressurizing screw shaft is placed on the drive shaft with the relevant parts hollow, so that the linear motion stroke can be made sufficiently large and the entire drive device can be compactly integrated. It becomes a stirring spot joining device.

  FIG. 1 is a schematic configuration diagram of a friction stir spot welding apparatus suitable for carrying out the present invention. This welding apparatus softens a workpiece by frictional heat generated by rotation of a center pin 1 and a shoulder pin 2. An apparatus for spot-joining by stirring, which includes a stirring motor 3 for rotating a shoulder pin 2 in which a center pin 1 is inserted, and a pressurizing motor 4 for driving the shoulder pin 2 straightly. In the friction stir spot welding device in which the center pin 1 protrudes and retracts from the tip of the shoulder pin 2, hollow portions 12 and 22 are formed in the center pin shaft 11 and the shoulder pin shaft 21, respectively. The tip end side of the pressurizing screw shaft 41 is inserted into the hollow portion 12 of the center pin shaft 11, and the tip end side of the center pin shaft 11 is inserted into the hollow portion 22 of the shoulder pin shaft 21. Drive A center pin driving motor 5 for positioning the center pin shaft 11 on the outer periphery of the core and the shoulder pin shaft 21 on the outer periphery of the center pin shaft 11 and moving the center pin 11 forward and backward. A friction stir spot joining device in which the center pin shaft 11 and the stirring motor 3 for rotating the shoulder pin shaft 21 and the shoulder pin shaft 21 are connected by transmission belts 51 and 31, respectively.

  In the friction stir spot welding device, a center pin 1 is inserted at a joint point of workpieces (not shown) to be joined, and a part of the workpiece is softened by frictional heat generated by the rotation of the center pin 1. The agitation is performed for spot joining, and the joining apparatus generally has the following configuration.

  The pressurizing motor 4 is fixed to the joining apparatus body 7 attached to the wrist 6 of the robot via a bracket 71, and the pressurizing screw shaft is connected to the output shaft 42 of the pressurizing motor 4. 41 is fixed. In the joining apparatus main body 7, a center pin driving motor 5, a stirring motor 3, a center pin 1 and a shoulder pin 2 driving section body 8 are built-in. A fixing arm 9 is attached to the outer front portion of the fixing arm 9, and a holding jig 91 for holding an object to be joined is disposed at the tip of the fixing arm 9.

  The center pin driving motor 5 and the agitating motor 3 are fixed to the driving unit body 8 via brackets 82 and 83, and the driving unit body 8 is a screw of a pressurizing screw shaft 41. A ball nut 81 that is screwed together with the center pin shaft 11 and the shoulder pin shaft 21 moves forward and backward, and this drive unit body 8 is a linear motion bearing disposed in the joining device body 7. 72 is guided.

  The center pin shaft 11 is configured such that the center pin 1 is screwed into a center pin screwed portion 13 formed on the tip end side thereof, and the rear of the screwed portion 13 of the center pin shaft 11 is a bolt. -It is connected to the shoulder pin shaft 21 through the ruspline 14, the distal end side of the pressurizing screw shaft 41 is inserted into the rear hollow portion 12, and the screw 15 is screwed on the outer periphery of the rear portion. .

  A pulley 17 is fixed to a ball screw nut 16 that is screwed into a screw 15 at the rear portion of the center pin shaft 11, and the center pin driving motor fixed to the drive unit main body 8 by a bracket 82. The rotational force from the rotor 5 is transmitted to the ball screw nut 16 through the transmission belt 51 and the pulley 17.

  The shoulder pin shaft 21 is configured such that the shoulder pin 2 is wedged to a shoulder pin fixing portion 23 formed on the front end side thereof, and the bore of the shoulder pin shaft 21 is disposed in the front half portion of the hollow portion of the shoulder pin shaft 21. The sprue line 14 is keyed, the bearing 24 of the center pin shaft 11 is disposed in the rear half of the hollow part, and the pulley 25 is fixed to the outer periphery of the rear half.

  A rotational force from the agitating motor 3 fixed to the drive unit main body 8 by a bracket 83 is transmitted to the pulley 25 via a transmission belt 31, and this rotation causes the shoulder pin 2 and the center to be rotated. The pins 1 are designed to rotate together.

  Then, the distal end side of the pressurizing screw shaft 41 is inserted into the hollow portion 12 of the center pin shaft 11, and the distal end side of the center pin shaft 11 is inserted into the hollow portion 22 of the shoulder pin shaft 21. A center pin shaft 11 is positioned on the outer periphery of the drive shaft core, and a shoulder pin shaft 21 is positioned on the outer periphery of the center pin shaft 11.

  In the friction stir spot welding gun having the above-described configuration, first, the robot 6 moves the entire friction stir spot welding device to a position facing a desired joining point of the objects to be joined.

  Therefore, the agitating motor 3 and the pressurizing motor 4 are driven, and the ball nut 81 is advanced by the pressurizing motor 4 so that the drive unit body 8 is moved to the agitating motor 3 and the center pin. Advancing toward the joining point of the workpiece together with the driving motor 5, the shoulder pin 2 and the center pin 1 are rotated together by the agitating motor 3. At this time, the tip of the center pin 1 is in a state of protruding from the shoulder portion 26 of the shoulder pin 2.

  When the shoulder portion 26 of the shoulder pin 2 comes into contact with the surface of the article to be joined by the pressurizing motor 4, the center pin 1 is inserted into the article to be joined and is in a rotating state at the joining point. At this time, the advancement of the pressurizing motor 4 is stopped, but the center pin 1 rubs against the workpiece to be melted by the rotation of the center pin 1 and dissolves a part of the workpiece to be stirred. The melted material performs spot bonding of the objects to be bonded. The shoulder portion 26 of the shoulder pin 2 is in a state of pressing the surface of the object to be joined in a molten state.

  When the joining operation is performed, the center pin driving motor 5 is driven, and the center pin 1 is pulled out from the joining point of the object to be joined and is the same as the shoulder portion 26 of the shoulder pin 2. The level or even more is pulled into the shoulder pin 2. During this time, since the agitating motor 3 is driven, the shoulder portion 26 of the rotating shoulder pin 2 operates so as to flatten the surface of the joining point of the object to be joined.

  It should be noted that the center pin 1 is raised or lowered with respect to the shoulder portion 26 of the shoulder pin 2 independently of the driving of the pressurizing motor 4 or the agitating motor 3. It can be arbitrarily adjusted by driving, the amount of protrusion and the pressing force of the center pin 1 with respect to the shoulder portion 26 and the pressing force can be arbitrarily adjusted, and the driving of the motor 5 is to dissolve the junction point. It can be operated when necessary according to the situation of the object.

  As described above, in the friction stir spot welding device according to the present invention, the center pin driving motor 5, the center pin shaft 11, and the shoulder pin shaft 21 for moving the center pin 1 back and forth independently are rotated. Since the agitating motor 3 and the shoulder pin shaft 21 are connected by transmission belts 51 and 31, respectively, the pressing force of the center pin 1 and the pressing force of the shoulder pin 2 can be individually adjusted, and the types of joining members It is possible to cope with the joining conditions of the center pin 1 that differ depending on the plate thickness, and it is not necessary to reverse the rotational direction of the shoulder pin 2 when the center pin 1 moves forward and backward. The transmission belts 31 and 5 can be prevented from being lowered and the joining conditions can be easily obtained, and the transmission of the outputs from the agitating motor 3 and the center pin driving motor 5 does not need to go through a complicated spline mechanism. Apparatus is simplified since in may be performed. In addition, since the tip side of the pressure screw shaft 41 is disposed on the drive shaft core with the related parts being hollow 12 and 22, the linear motion stroke can be made sufficiently large and the entire drive device can be made compact. It is something that can be done.

FIG. 1 is a schematic configuration diagram of a friction stir spot welding device according to the present invention. FIG. 2 is a schematic view taken along line AA in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Center pin 2 Shoulder pin 3 Motor for stirring 4 Motor for pressurization 5 Motor for driving center pin 11 Center pin shaft 12 Hollow portion of center pin shaft 21 Shoulder pin shaft 22 Shoulder Pin shaft hollow 31, 51 Transmission belt 41 Screw shaft for pressurization

Claims (1)

A device for softening and agitating the object to be welded by frictional heat generated by the rotation of the center pin and the shoulder pin and spot joining, the agitating motor for rotating the shoulder pin with the center pin inserted therein A friction stir spot welding apparatus having a pressurizing motor for driving the shoulder pin in a straight line so that the center pin protrudes and protrudes from the tip of the shoulder pin, the center pin shaft and the shoulder pin shaft; Each hollow part is formed, and the tip side of the pressure screw shaft is inserted into the hollow part of the center pin shaft, and the tip side of the center pin shaft is inserted into the hollow part of the shoulder pin shaft, thereby driving the pressure screw shaft. A center pin driving motor for positioning the center pin shaft on the outer periphery of the shaft core and the shoulder pin shaft on the outer periphery of the center pin shaft, respectively, and moving the center pin independently. Printer - the pin shaft, and the shoulder - stirrer rotating pin shaft motor - motor and shoulder - a pin shaft, the friction stir spot joining device, characterized in that linked with each transmission belt.