JP2003200271A - Loosening device of electrode tip for spot welding - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a loosening device of an electrode tip for spot welding which has a simple structure and with which a loosening work of an electrode tip is quickly and surely performed. <P>SOLUTION: The loosening device of an electrode tip for spot welding is composed of an annular main wheel 15 which has toothed parts 16 and 17 on the outer periphery and the inner periphery, respectively, and is freely rotatable around a center line M-M, a plurality of clamping and holding bodies 32 which are freely rotatably and pivotally supported on a rotary body 29 being engaged with the toothed part 17 on the inner periphery of the main wheel 15, an idle gear 37 which is engaged with the toothed part 16 on the outer periphery of the main wheel 15 to rotate the main wheel 15, and a driving means 1 which transfers a driving force to the idle gear 37. A stopping means is provided on the side of the idle gear 37 for allowing the rotation of the rotary body 29 so that the rotary body 29 is stopped and the electrode tip 40 which is clamped and held by the clamping and holding bodies 32 is detached from the mounting part, when the respective clamping and holding bodies 32 clamp and hold the electrode tip 40 by the rotation of the main wheel 15. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode tip loosening device for spot welding used when removing an electrode tip from an electrode rod for spot welding.

[0002]

2. Description of the Related Art When a tip attached to the tip of an electrode rod is damaged, it is necessary to replace the tip. To do so, the old chip must first be removed. Conventionally, in order to remove the tip that is taper-fitted or screwed on the tip of the electrode rod, a spanner-shaped object is fitted in the notch provided in the cylindrical tip, and it is attached to the attachment part of the welding machine etc I rotated it slightly to loosen it and then removed it.

[0003]

It is troublesome and troublesome to fit a wrench-shaped object into a notch provided in a cylindrical tip and loosen it by turning it. Therefore, a device for removing the electrode tip by clamping (clamping) the tip with a plurality of clamping bodies is being developed, but the electrode tip does not loosen unless it is clamped and rotated. Therefore, there has been a demand for a simple device that surely rotates and loosens the tip. It is an object of the present invention to provide an electrode tip loosening device for spot welding having a simple structure that enables quick and reliable loosening work of the electrode tip.

[0004]

The present invention has been made to solve the above-mentioned problems, and is characterized in that it has teeth 16 and 17 on its outer circumference and inner circumference and has a center line MM. An annular main wheel 15 which is rotatable around the center and a rotating body 29 which meshes with an inner peripheral tooth portion 17 of the main wheel 15.
A plurality of holding bodies 32 rotatably supported by the outer peripheral tooth portion 1 of the main wheel 15 in order to rotate the main wheel 15.
6 is provided with an intermediate gear 37 that meshes with the intermediate gear 37 and a drive unit 1 that transmits a driving force to the intermediate gear 37. The sandwiching body 32 has an inner portion of the valley portion when the valley portion faces the center line MM. The contact circle is larger than the outer diameter of the electrode tip 40 attached to the attachment portion, and the peak portion of each holding body 40 has the center line M-M.
The inscribed circle of the mountain portion when facing the electrode tip 40
In an electrode tip loosening device for spot welding rotatably configured to be smaller than the outer diameter of the rotating body 29, the rotating body 29 is stopped when each holding body 32 holds the electrode tip 40 by the rotation of the main wheel 15. In addition, a stopping means for permitting rotation of the rotating body 29 is provided on the intermediate gear 37 side so that the electrode tip 40 held by the holding body 32 can be removed from the mounting portion.

Therefore, the tip pinching means can pinch and loosen the spot welding electrode tip 40 by the driving means 1, and can be easily and quickly removed.

Moreover, the electrode chips 40 can be reliably clamped radially by the plurality of clamping bodies 32, and the electrode tip 40 for sput welding can be loosened and removed by rotating the rotating body 29.

Further, the casing 5 is provided so as to be movable by a moving means in a direction in which each holding body 32 holds the electrode tip 40 in a state where it is detached from the mounting portion. In such a case, the electrode tip 4 can be more easily and quickly.
It becomes possible to remove 0.

[0008]

1 to 7 show an embodiment of the present invention. As shown in FIG. 1, FIG. 2 and FIG. 3, a motor case 10 of a motor 1 as a driving means has a horizontal direction. A casing 5 is attached to the.

The upper and lower walls 5a, 5b of the casing 5 are respectively provided with insertion holes 21 centered on the center line MM at the tips thereof, and the tip of the casing 5 is provided with the center line MM.
A ring-shaped main wheel 15 having tooth portions 16 and 17 on its outer and inner circumferences is rotatably provided so as to center on. An annular ridge 18 is provided below the main wheel 15.
Is projected, and the ridge 18 is rotatably fitted in a fitting recess 23 formed in the casing 5.

So that it is located above the main wheel 15,
A disc-shaped upper support plate 25 is rotatably fitted to the upper wall 5a of the casing 5. Further, a disk-shaped lower support plate 27 is rotatably fitted in the protrusion 18 of the main wheel 15. The upper support plate 25 and the lower support plate 27 form a rotary body 29.

A plurality of (three in the present embodiment) shaft portions 33 of planetary gears 32 serving as a sandwiching body are rotatably inserted into the upper and lower support plates 25 and 27 so that the teeth of each planetary gear 32 are toothed. The portion 32 a meshes with the inner peripheral tooth portion 17 of the main wheel 15. Each planet gear 32 has a tooth portion 32.
A cutout 35 is formed by cutting a part of a flat or curved.

Therefore, in the initial state in which the notch 35 of each planetary gear 32 faces the center line MM, each notch 35 becomes a valley (small diameter portion), and the inscribed circle of each valley becomes a spot. By forming a tip insertion opening having a diameter larger than that of the welding electrode tip 40, the spot welding electrode tip 40 can be inserted. Moreover,
The inscribed circle when the crest portion (large diameter portion provided with the tooth portion 32a) of each planetary gear 32 faces the center line MM is
A tip insertion opening having a diameter slightly smaller than the outer diameter of the electrode tip 40 is formed. A plurality of (three in the present embodiment) planetary gears 32 constitute chip holding means.

An intermediate gear 37, which constitutes an interlocking mechanism, is interposed between the main wheel 15 and the drive gear 12 provided on the drive shaft 11 of the motor 1. The intermediate gear 37 has a cylindrical boss portion 31 having an internal thread portion 30 on its inner surface.
And a screw shaft 34 in the vertical direction that is screwed into the female screw portion 30.
Is inserted into the boss portion 31. The screw shaft 34 and the boss portion 31 of the intermediate gear 37 constitute a moving means for moving the casing 5 up and down. In addition, the screw shaft 34
A right-handed screw or a left-handed screw can be appropriately adopted.

The screw shaft 34 and the casing 5 cannot rotate relative to each other by, for example, key fitting, and the casing 5 can move up and down with respect to the screw shaft 34. Further, the upper and lower ends of the screw shaft 34 are connected to a fixing frame body 45 that can be fixed at any place. The plate 6 is externally fitted to the boss portion 31, and the plate 6 is fixed to the intermediate gear 37 by bolts 8 so as to rotate integrally with the intermediate gear 37.

An engaging portion 20 as a stopping means is fixed to the plate 6 by a fixing means such as a bolt 22. The engaging portion 20 engages with a recess 19 as an engaged portion formed on the upper support plate 25. As shown in FIG. 3, the tip end surface of the engaging portion 20 is a convex arc surface centered on the screw shaft 34. Further, the concave portion 19 of the upper support plate 25 is an arc surface that follows the shape of the tip surface of the engaging portion 20. Therefore, when the engaging portion 20 is engaged with the recess 19 of the upper support plate 25, the intermediate gear 37 and the plate 6 meshing with the main wheel 15 are rotatable, but the upper support plate 25
Is incapable of rotating because it abuts on the engaging portion 20.

An embodiment of the present invention has the above-mentioned structure. Next, a usage example of such a device will be described. First, the state in which the valley portion 35 of the planetary gear 32 is oriented in the center line M-M direction is the initial state, and the tip insertion opening formed from each valley portion 35 is larger than the outer diameter of the spot welding electrode tip 40. Has become. The engaging portion 20 fixed to the plate 6 is engaged with the recess 19 of the plate 6 (see FIG. 3). Therefore, the upper support plate 25,
The upper support plate 25 and the lower support plate 27 that holds the planetary gear 32 are not rotated but fixed.

In this state, the electrode tip 40 attached to the electrode rod for spot welding is inserted into the tip insertion opening, the motor 1 is operated to rotate the drive gear 12 forward, and the main wheel is passed through the intermediate gear 37. When the wheel 15 is rotated, the planetary gears 32 that mesh with the rotating main wheel 15
Rotates (rotates around the shaft 33).

When the planetary gear 32 rotates, the diameter of the tip insertion port is reduced. That is, since the planetary gear 32 in the initial state rotates about its axis, the tooth portions 32a of each planetary gear 32 bite into the electrode tip 40 and sandwich and fix the electrode tip 40. The engaging portions 20 fixed to the plate 6 are separated from the recesses 19 of the plate 6 and released from each other (see FIG. 4).

As a result, the upper and lower support plates 25,
The rotation of 27 becomes free. Since each planetary gear 32 bites into the electrode tip 40 and does not rotate, the upper and lower support plates 25, 27 which are allowed to rotate together with the main wheel 15
Rotates to a predetermined angle. As a result, the planetary gear 3
Since 2 revolves (rotates around the center line MM) while biting into and sandwiching the electrode tip 40 from the three-point direction, the electrode tip 40 can be loosened by turning (FIG. 5).
reference).

Further, since the intermediate gear 37 is screwed to the fixed screw shaft 34, the casing 5 descends, and the loosened electrode tip 40 can be reliably removed.

Further, the upper and lower support plates 25, 27
6 is rotated to the position shown in FIG. 6 and then the motor 1 is rotated in the reverse direction, whereby the upper and lower support plates 25 and 27 can be rotated in the opposite direction. The engaging portion 20 fixed to the plate 6 again is the concave portion 1 of the plate 6.
Since it engages with 9, the upper and lower support plates 25,
The rotation of 27 is restricted and the planetary gear 32 can be rotated to return to the initial state in which the tip insertion opening has a large diameter, and the electrode tip 40 can be automatically taken out.

The electrode tip 40 attached to the electrode rod for spot welding can be inserted into the tip insertion opening from below, but in such a case, the casing 5
It is a structure to raise. In short, in the moving means for moving the casing 5 up and down, the tip holding means is the electrode tip 40.
It suffices that the casing 5 is operated in the direction of sandwiching and the casing 5 is moved in the direction of removing the electrode tip 40.

Further, the sandwiching body may be one having a cam surface whose radius gradually changes, other than the planetary gear, and is not particularly limited. Moreover, when the planetary gears 32 sandwich the electrode tip 40, the engaging portion 20 is
The engaging portion 20 is separated from the concave portion 19 of the plate 6.
Although the width in the rotation direction of the support plate is set, the upper and lower support plates 25, 27 and the support plates 25, 27
A bush (not shown) made of rubber or synthetic resin material may be interposed between the bush 33 and the shaft portion 33 of the planetary gear 32. In such a case, the planetary gears 32 hold the electrode tip 40, and the engaging portion 20 and the recess 1 of the plate 6 are held.
Even if there is a slight error in the timing of engagement and disengagement of No. 9, the error can be absorbed and there is a buffering effect.

Further, in the above-mentioned embodiment, the plate 6 and the engaging portion 20 are illustrated as separate bodies, but they may be constructed as an integral member. Moreover, the plate 6 is a gear having an outer diameter substantially the same as the diameter of the intermediate gear 37 and a tooth portion on the outer periphery (outer peripheral portion excluding the engaging portion 20) thereof. On the other hand, the upper support plate 25
It is also possible to form a gear having a tooth portion that meshes with the tooth portion on its outer periphery (outer peripheral portion excluding the concave portion 19). By using the gear mechanism in this manner, the upper and lower support plates 25, 27 (rotating body 29) can be forcibly rotated, and there is an advantage that each planetary gear 32 can be reliably revolved.

In this embodiment, the boss portion 3 of the intermediate gear 37 is used.
Since the casing 5 is moved by inserting the single screw shaft 34 into the unit 1, the configuration is simple and the number of parts can be reduced as compared with the case where a plurality of screw shafts 34 are adopted.

[0026]

As described above, according to the present invention, when the main body rotates, each holding body holds the electrode tip, the rotating body is stopped, and the electrode tip held by the holding body can be detached from the mounting portion. In addition, since the stop means for allowing the rotation of the rotating body is provided on the side of the intermediate gear, the rotational driving force of the stopping means can be obtained by the rotation of the intermediate gear, and the rotating body can be moved at a predetermined position. No special complicated mechanism for stopping is required, and the simple structure allows the electrode tip to be loosened quickly and reliably, and can be applied to the work by the robot. Further, it is not necessary to provide a cutout for hooking a spanner or a wrench on the tip.

[Brief description of drawings]

FIG. 1 is a sectional front view showing a main part of an apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional plan view of the same.

FIG. 3 is a sectional plan view showing an initial state of the planetary gear.

FIG. 4 is a cross-sectional plan view showing a state in which the engagement portion stops the upper support plate and rotates the planetary gear to sandwich the electrode tip.

FIG. 5 is a cross-sectional plan view showing a state in which the upper support plate is rotated to rotate the electrode tip.

FIG. 6 is a cross-sectional plan view with the electrode tip removed.

FIG. 7 is a partial cross-sectional side view showing the entire apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Driving means (motor), 5 ... Casing, 15 ... Main wheel, 16 ... Outer peripheral tooth part, 17 ... Inner peripheral tooth part, 29 ... Rotating body, 32 ... Clamping body (planetary gear), 37 ... Intermediate gear, 4
0 ... Electrode tip, MM ... Center line of tip insertion port

Claims (2)

[Claims] 1. An annular main wheel (15) having tooth portions (16, 17) on its outer circumference and inner circumference and rotatable about a center line (MM), and the main wheel (15). )
In order to rotate the plurality of holding bodies (32) rotatably supported by the rotating body (29) so as to mesh with the inner peripheral tooth portions (17) of the main wheel (15), the main wheel (15) An intermediate gear (37) that meshes with the outer peripheral tooth portion (16) of the gear, and a drive means (1) that transmits a driving force to the intermediate gear (37). Line (M-
M), the inscribed circle of the valley portion is larger than the outer diameter of the electrode tip (40) attached to the attachment portion, and the peak portion of each holding body (40) has the center line (M- The inscribed circle of the mountain portion when facing the M) is the electrode tip (40)
In an electrode tip loosening device for spot welding, which is rotatably configured so as to have a smaller diameter than the outer diameter of the holding body (3), the holding body (3) is rotated by rotating the main wheel (15).
When the electrode tip (40) is clamped by the rotating body (2)
9) is stopped, and the electrode tip (40) held by the holding body (32) can be detached from the mounting portion.
An electrode tip loosening device for spot welding, characterized in that stop means for allowing rotation of the rotating body (29) is provided on the intermediate gear (37) side. 2. The casing (5) comprises a holding body (3).
The electrode tip loosening device for spot welding according to claim 1, wherein 2) is provided so as to be movable by a moving means in a direction in which the electrode tip (40) is sandwiched and separated from the mounting portion.