JP4842652B2 - Stud welding equipment - Google Patents

Description

  The present invention relates to a stud welding apparatus.

  A configuration of a stud welding device called a so-called stud welding gun is disclosed in Patent Document 1, for example. In such a stud welding apparatus, a drive main shaft called, for example, a front shaft is built in a main body housing, and a chuck is attached to the tip end side of the drive main shaft via a chuck adapter. In general, various chucks corresponding to the thickness of one end of the stud used for welding are prepared, and the chuck is replaced with an appropriate one according to the shape of the stud. This stud welding apparatus is used in a state where one end of the stud is held by the chuck.

  The drive spindle is normally held in the body housing so as to be movable in a predetermined stroke in the axial direction, and is always urged in the pushing direction by a spring, while being driven to be pulled up by electromagnetic force at an appropriate time. It has become. In the chuck adapter, a power feeding cable is connected to a conductor portion on a distal end side which is insulated from the proximal end side.

  Welding using the above stud welding apparatus is generally performed as follows. A predetermined stud is held at the proximal end of the chuck. An operator holding the main body housing presses the ferrule externally fitted to the tip of the stud against the base material by using a ferrule pressing guide attached to the main body housing. Since the ferrule is externally fitted so as to be axially movable relative to the stud, at this time, the stud has a shape in which the tip is pressed against the base material by the elastic force of the spring that urges the driving main shaft in the pushing direction. Become. When the start switch arranged at an appropriate part of the main body housing is pressed while this state is maintained, the drive main shaft or stud is pulled up by a predetermined distance by electromagnetic force, and a predetermined clearance is provided between the tip of the stud and the base material. it can. Next, a welding current is supplied from the power supply cable. An arc discharge occurs between the tip of the stud and the base material, and the tip of the stud is melted by this discharge energy. The electromagnetic force is turned off at an appropriate time, and a pressing force directed toward the base material is applied to the stud by the spring. The molten metal fills the inner space of the ferrule and then solidifies, completing the welding of the stud tip to the base material.

JP 2002-307167 A

  By the way, the drive main shaft is capable of reciprocating in the axial direction with respect to the main body housing, but in order to ensure the holding stability of the chuck adapter and the stud held via the chuck, the drive main shaft is Should be non-rotatable about the axis relative to the body housing. Also, in this type of stud welding device, as soon as the electromagnetic force is released, the driving main shaft or stud is prevented from suddenly moving in the pushing direction by the elasticity of the spring, and the stud tip is prevented from abutting against the base material. For this reason, there is a case in which a structure is provided in which the movement of the drive spindle in the pushing direction is buffered by a shock absorber attached outside the main body housing. In this case, it is necessary to restrict the rotation of the drive main shaft about the axis in order to surely bring the stopper arm extending from the drive main shaft into contact with the push rod of the shock absorber.

However, as described above, a power feeding cable is connected to the chuck adapter integrated with the drive main shaft, and this power feeding cable is a cable having a relatively heavy weight to ensure a large current capacity. For this reason, depending on the posture adopted by the stud welding apparatus, a large rotational force may act on the drive main shaft due to the weight of the power feeding cable or the tensile force acting on the power feeding cable. Therefore, for example, the rotation restricting protrusion that extends from the drive main shaft or the rotation restricting protrusion only by restricting the rotation of the drive main shaft by slidingly engaging the stopper arm with the guide slot provided in the main body housing. Alternatively, the smooth axial movement of the drive main shaft may be hindered by the frictional force acting between the stopper arm and the guide slot. If it does so, the welding operation by a stud welding apparatus will become impossible.

  The present invention has been conceived under the circumstances described above, and without restricting the axial movement of the drive spindle, the rotation of the drive spindle around the axis is properly regulated and stable for a long period of time. It is an object of the present invention to provide a stud welding device capable of welding work.

  In order to solve the above problems, the present invention employs the following technical means.

That is, a stud welding device provided by the present invention includes a main body housing, a driving main shaft held in the main body housing so as to be movable in the axial direction, and connected and fixed to the front end side of the driving main shaft. A stud welding device comprising a chuck adapter to which a holding chuck is attached and a power supply cable connected to the chuck adapter, wherein the drive main shaft is provided with a guide protrusion extending laterally, The guide protrusion supports a rotating body that freely rotates around a predetermined rotation axis, while the main body housing has two guide surfaces that extend in parallel with the axis of the drive main shaft and face each other in parallel. to have a guide slot and is formed, Ki that the drive spindle is moved in the axial direction, the rotating body have the two guide surfaces Wherein the rolling to isosamples contact Re or one.

  In another preferred embodiment, two rotating bodies are provided, one rotating body is brought into contact rolling with one of the two guide surfaces of the guide slot, and the other rotating body is disposed in the guide slot. It is comprised so that it may contact and roll on the other of two guide surfaces.

  According to such a configuration, when the drive spindle, chuck adapter, or further, the stud held on the tip side of the stud via the chuck moves in the axial direction with respect to the main body housing, it is supported by the guide protrusion and freely rotates. The rotating body rolls on the guide surface of the guide slot. Therefore, even if an external force in the rotational direction acts when the drive main shaft moves in the axial direction, the rotation of the drive main shaft is prevented. Further, since only rolling friction acts between the rotating body and the guide surface of the guide slot, the axial movement of the drive main shaft is not hindered.

Therefore, this stud welding apparatus has a rotational force acting on the chuck adapter or the drive main shaft due to the weight or tension of the power supply cable depending on the posture thereof, so that the drive main shaft does not rotate inadvertently. without the movement is inhibited, it is possible to continue the proper welding operation.

  In a preferred embodiment, the rotating body is constituted by an outer ring of a bearing in which an inner ring is fixed to the guide protrusion.

In this way, since a commercially available bearing can be employed, the manufacturing cost can be reduced.

  In a preferred embodiment, the main body housing is further provided with a shock absorber having an axis parallel to the axis of the drive main shaft, and the guide protrusion is formed so as to be able to abut against a working rod of the shock absorber. Has been.

  If it does in this way, the member for implement | achieving the buffer movement effect | action of the drive main shaft which cooperated with the shock absorber can be combined with the said guide protrusion.

  Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the drawings.

  Hereinafter, a preferred embodiment of the present invention will be specifically described with reference to the drawings.

  1 to 4 show an embodiment of a stud welding device 100 of the present invention. As shown in FIG. 1, the stud welding apparatus 100 includes a cylindrical main body housing 200, a driving main shaft 300 that is held in the main body housing 200 so as to be axially movable, and a tip of the driving main shaft 300. And a chuck adapter 400 connected to the side. The chuck adapter 400 is attached with a chuck 450 that can be fitted and held on the base end side of the stud 500 in accordance with the thickness of the base end side of the stud 500 to be used. The main body housing 200 is integrally extended with a grip portion 210 held by an operator.

  As shown in FIG. 3, the drive main shaft 300 includes a distal end side shaft portion 310, a large diameter portion 320 adjacent to the proximal end side of the distal end side shaft portion 310, and a proximal end side further than the large diameter portion 320. And a small-diameter pull-up rod portion 330 extending to the center. In the main body housing 200, a holding hole 220 for holding the drive main shaft 300 so as to be movable in the axial direction is formed. The holding hole 220 includes a distal end side small diameter portion 222 that supports the distal end side shaft portion 310 of the drive main shaft 300 through the sliding bearing 221 so as to be axially slidable and capable of axial rotation. A large-diameter portion 223 that continuously accommodates the large-diameter portion 320 on the end side. The large-diameter portion 223 of the holding hole 220 has an axial length that is larger than the axial length of the large-diameter portion 320 of the drive main shaft 300. The axial movement stroke of the drive main shaft 300 is defined by the large diameter portion 320 coming into contact with the step portion 224 that borders the small diameter portion 222 and the large diameter portion 223 of the holding hole 220. Thus, the driving main shaft 300 whose front end of the moving stroke is defined can be lifted by a predetermined distance as long as the large diameter portion 320 allows the axial length of the large diameter portion 223 of the holding hole 220 to be allowed. The driving main shaft 300 is always pushed in the pushing direction by elastically contacting the front end of the compression coil spring 230 disposed in the large-diameter portion 223 of the holding hole 220 with the surface on the proximal end side of the large-diameter portion 320. Is elastically energized.

  On the base end side in the main body housing 200, a lifting piece 240 made of a magnetic material is provided with a bottomed hole 241 that can accommodate a portion on the base end side of the lifting rod portion 330 on the front end side through a bearing. Is held axially movable. The pulling piece 240 is also always biased toward the distal end by a spring 250 having a relatively weak elasticity. An electromagnetic coil 260 is also incorporated on the base end side of the main body housing 200 so as to surround the lifting piece 240. A stopper shaft 261 for defining the rear end of the moving stroke of the lifting piece 240 is provided at the rear end of the space surrounded by the electromagnetic coil 260.

A clamp plate 252 having a predetermined thickness fixed to the lifting piece 240 by a screw 251 is swingably provided at the entrance portion of the bottomed hole 241 of the lifting piece 240. The clamp plate 252 is provided with a holding hole 253 through which the lifting rod portion 330 of the drive main shaft 300 is inserted.

  As shown in FIG. 3, the large-diameter portion 320 of the drive main shaft 300 is provided with a shaft-shaped guide protrusion 340 extending in the direction perpendicular to the axis. The guide projection 340 also includes an inner ring 361, an outer ring 362, and a bearing composed of a plurality of balls 363 interposed between the inner ring 361 and the outer ring 362, that is, a rolling ball bearing 360. It is attached by external press fitting. The outer ring 362 of the bearing 360 functions as a rotating body that rotates around the axis of the guide protrusion 340. The guide protrusion 340 further includes a stopper portion 341 that extends further than the bearing 360 and can abut on a working rod 281 of a shock absorber 280 described later.

  On the other hand, as shown in FIGS. 3 and 4, the main body housing 200 is formed with a guide slot 270 in which the outer ring 362 (rotating body) of the bearing 360 can contact and roll. The guide slot 270 includes two guide surfaces 271 and 272 that face each other in parallel and extend in a straight line parallel to the axis of the drive main shaft 300. The outer ring 362 of the bearing 360 is positioned. The distance between the two guide surfaces 271 and 272 is slightly larger than the outer diameter of the outer ring 362 of the bearing 360.

  As shown in FIG. 3, a shock absorber 280 is attached to the main body housing 200. The shock absorber 280 includes a cylinder 282 and an action rod 281 incorporated in the cylinder. The shock force in the axial direction on the action rod 281 is reduced by the viscosity of the internal oil. It is a well-known thing which realizes a proper axial movement. The shock absorber 280 also has the axis parallel to the axis of the drive main shaft 300 and the position where the stopper 341 can come into contact with the end of the action rod 281 extending rearward. It is attached to the main body housing 200.

  As shown in FIG. 1, the chuck adapter 400 is connected and fixed to the distal end side of the drive main shaft 300 by a screw, and is connected to a distal end side portion 410 insulated from the rear end side portion. 370 is connected. A chuck 450 that is externally fitted to one end of the stud 500 and holds the stud 500 is detachably attached to the tip end side of the chuck adapter 400. The chuck 450 corresponds to the shape of the base portion of the stud 500, and various types of chucks that can hold various studs 500 are prepared. In the example shown in the figure, a socket portion 451 having a slit is formed on the tip side of the chuck 450, and a base portion of a predetermined stud 500 is fitted and held in the socket portion 451. .

In FIG. 1, reference numeral 290 indicates a ferrule pressing guide. The ferrule pressing guide 290 is supported at a distal end of a rod-shaped support member 291 that has a base end supported by an appropriate portion of the main body housing 200 and extends a predetermined distance forward. A fork-shaped pressing portion 292 formed so as to hold the stud 500 from the lateral direction is formed (see FIG. 2) . As shown in FIG. 1, the ferrule 510 is a cylindrical member having a predetermined axial length fitted to the tip of the stud 500, and is formed of a heat-resistant ceramic or the like. The ferrule 510 is fitted so that the base end side is slidable on the outer periphery of the stud 500, while a space that is open to the front end side with an inner diameter larger than the diameter of the stud 500 is secured on the front end side.

An activation button 211 is provided on the grip portion 210 extending from the main body housing 200. In addition, a cable 212 for supplying power to the electromagnetic coil 260 is housed inside the grip portion 210. The cable 212 is bundled with a cable 214 extending from the switch circuit 213 that cooperates with the activation button 211, and is extended from the lower end portion of the grip portion 210.

  Next, the operation of the stud welding apparatus 100 configured as described above will be described.

  The operator holds the stud welding device 100 and takes a posture of pressing the ferrule 510 fitted to the tip of the stud 500 against the base material M. Since the ferrule 510 is pressed by the ferrule pressing guide 290 as described above, the position in the axial direction of the stud 500 of the stud welding device 100 with respect to the base material M is defined through the ferrule 510 and the ferrule pressing guide 290 at this time. The At this time, the stud 500 is elastically pressed in the pushing direction by the compression coil spring 230 that presses the drive main shaft 300, so that the tip 500 is elastically abutted against the base material M.

  When the start button 211 is pressed, the electromagnetic coil 260 is first energized, and the pulling piece 240 is moved backward by the electromagnetic force. Along with this, the clamp plate 252 swings, and the pull-up rod portion 330 is hooked and clamped on the clamp plate 252. Thereafter, the drive main shaft 300 is pulled up by a predetermined distance according to the movement of the pulling piece 240, and accordingly, the chuck adapter 400, the chuck 450, or the stud 500 are pulled up by a predetermined distance. At this time, while the ferrule 510 is pressed against the base material M, a gap corresponding to the above-described lifting amount is generated between the base material M and the tip of the stud 500.

Next, power is supplied from the power supply cable 370, arc discharge occurs between the base material M and the tip of the stud 500, and the tip of the stud 500 is melted by the energy. The energization of the electromagnetic coil 260 is interrupted at the next timing, the lifting piece 240 returns to the original state by the elasticity of the spring 250 , the clamp of the lifting rod portion 330 by the clamp plate 252 is also released, and the drive main shaft 300 or the stud 500 is The compression coil spring 230 is pressed toward the base material M with a predetermined elasticity. The movement of the drive spindle 300 at this time is such that the stopper 341 formed at the tip of the guide projection 340 comes into contact with the end of the action rod 281 of the shock absorber 280 and pushes in the action rod 281. It will be moderate. As a result, the inner space of the ferrule 510 is filled with the molten metal resulting from the melting of the tip of the stud, and eventually the molten metal is solidified as if it was cast into the inner space of the ferrule 510. When the chuck 450 is detached from the base end of the stud 500 and the ferrule 510 is broken and removed, the welding of the stud 500 to the base material M is completed.

As described above, in the stud welding apparatus 100, in the course of operation, the drive main shaft 300 is once pulled up and then pushed out by the elastic force of the compression coil spring 230 to perform an axial reciprocating motion. At this time, when selecting the direction in which the stud 500 is to be welded, or when changing the position of the stud welding device 100 when the stud 500 is mounted, the power supply cable 370 is relatively heavy. In response to the force, the driving main shaft 300 frequently receives a rotational force around the axis.

  However, in the stud welding device 100 having the above-described configuration, the drive main shaft 300 is configured such that the rotating body (outer ring 362) provided on the guide protrusion 340 contacts the guide surfaces 271 and 272 of the guide slot 270 of the main body housing 200. There is no rotation around the axis. Further, when the driving main shaft 300 moves in the axial direction, the rotating body rolls in contact with the guide surfaces 271 and 272 of the guide slot 270. Therefore, a resistance that hinders the axial movement of the drive main shaft 300 hardly occurs.

Thereby, according to the stud welding apparatus 100 of the said structure, it becomes possible to continue the welding operation stable for a long period of time.

  In the above-described embodiment, a part of the guide protrusion 340 to which the rotating body is to be attached is used as the stopper portion 341 for pushing in the action rod 281 of the shock absorber 280. When the stud 500 is configured so that the operation of pressing the stud 500 against the base material M after the arc discharge is relaxed by the shock absorber 280, the number of parts can be reduced, and the overall configuration of the stud welding apparatus 100 can be simplified.

  Of course, the scope of the present invention is not limited to the above-described embodiments, and all modifications within the scope of the claims are included in the scope of the present invention.

In the embodiment, a commercially available bearing (rolling ball bearing) 360 is used as a rotating body that enters the guide slot 270 formed in the main body housing 200 and prevents the rotation of the drive main shaft 300. However, the specific configuration of the rotating body is as follows. Not limited to this.

In the embodiment, one bearing 360 as the rotating body is provided for the guide protrusion 340, but the number of rotating bodies is not limited to this. For example, as shown in FIG. 5, when two bearings 360 are used, one of which is in contact rolling with one inner surface 271 of the guide slot 270 and the other is in contact rolling with the other inner surface 272 of the guide slot 270. Of course, it is also included in the scope of the present invention.

Furthermore, the configuration for lifting the drive main shaft 300, the configuration for releasing the lifting force and pressing it in the direction of the base material M, and the like are not limited to those specifically described in the embodiment.

  Furthermore, although embodiment has employ | adopted the structure as what is called a stud welding gun which the grip part 210 is provided in the main body housing 200, and an operator hold | grips the grip part 210 and works, this invention is this structure. Without being limited thereto, the main body housing may be supported by, for example, a welding robot.

It is a longitudinal cross-sectional view which shows one Embodiment of the stud welding apparatus which concerns on this invention. It is sectional drawing which follows the II-II line of FIG. It is a principal part enlarged view of FIG. It is the IV-IV arrow line view of FIG. It is explanatory drawing of other embodiment.

100 Stud Welding Device 200 Main Body Housing 210 Grip Portion 211 Start Button 220 Holding Hole 230 Compression Coil Spring 240 Lifting Piece 260 Electromagnetic Coil 270 Guide Slot 280 Shock Absorber 281 Working Rod 290 Ferrule Pressing Guide 300 Drive Main Shaft 310 Tip Side Shaft 320 Large Diameter Part 330 lifting rod part 340 guide protrusion 341 stopper part 360 rolling ball bearing (bearing)
361 Inner ring 362 Outer ring (rotating body)
370 Feed cable 400 Chuck adapter 450 Chuck 500 Stud 510 Ferrule M Base material

Claims (4)

A main body housing, a drive main shaft that is held in the main body housing so as to be movable in the axial direction, a chuck adapter that is connected and fixed to the front end side of the main drive shaft, and to which a stud holding chuck is attached; A stud welding device comprising a connected feeding cable,
The drive main shaft is provided with a guide protrusion extending laterally, and the guide protrusion supports a rotating body that freely rotates around a predetermined rotation axis,
Above body housing extends parallel to the axis of the drive spindle, and are guide slot is formed to have a two guide surfaces parallel to and facing each other,
If this driving spindle to move in the axial direction, the rotating body, characterized by rolling to isosamples contact with either of the two guide surfaces, the stud welding apparatus. Two rotating bodies are provided. One rotating body rolls in contact with one of the two guide surfaces of the guide slot, and the other rotating body contacts the other of the two guide surfaces of the guide slot. The stud welding device according to claim 1, wherein the stud welding device is configured to roll . The stud welding device according to claim 1 or 2, wherein the rotating body is configured by an outer ring of a bearing in which an inner ring is fixed to the guide protrusion . The aforementioned main body housing, and a shock absorber having an axis parallel to the axis of the drive spindle is attached, the guide protrusion is made form as can contact with the working rod of the shock absorber, according to claim The stud welding apparatus according to any one of 1 to 3 .

Images