JP4128732B2 - Electrode positioning jig - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrode positioning jig for a plasma torch for appropriately positioning a cathode side electrode used in a plasma torch with respect to an anode side electrode.
[0002]
[Prior art]
FIG. 5 is a front sectional view of the head portion of the plasma welding torch. In addition, the lower part in the same figure becomes a front end side, and an upper part becomes a rear end side in the same figure. The torch body 1 has a structure in which a cathode fitting 2 and an anode fitting 3 are molded with an insulator 4. A cap 5 is screwed onto the axial center of the cylindrical cathode fitting 2. An electrode holder 6 is screwed onto the axis of the cap 5. A slit (not shown) in the axial direction is formed in the inclined portion 6a of the electrode holder 6. When the electrode holder 6 is screwed into the cap 5, the radius of the inclined portion 6a decreases, and a rod-like tungsten electrode ( Electrode) 7 is firmly held. As a result, in a state where the electrode holder 6 is screwed into the cap 5, the cap 5 and the tungsten electrode 7 are substantially integrated. Here, the tungsten electrode 7 is positioned so as to be L ± α (where 2α is a positioning allowable range of the cap 5 with respect to the cathode fitting 2) from the tip 5a of the cap 5. The cap 5 is prevented from rotating by tightening the lock nut 8 and is fixed to the torch body 1. An O-ring 9 is attached to the groove provided on the outer periphery of the cap 5.
[0003]
A female screw 3f and a male screw 3M are formed on the inner peripheral surface and the outer peripheral surface, respectively, at the distal end portion of the anode fitting 3 formed in a cylindrical shape. A nozzle electrode 10 made of a copper alloy is screwed into the female screw 3f. The nozzle electrode 10 is screwed so that the side surface (upper surface) 10a of the flange portion comes into contact with the end surface (lower surface) 3a of the anode fitting 3, and when the side surface 10a contacts the end surface 3a, the small diameter hole 11 is formed from the end surface 3a. The distance to the end (upper end) 11a (predetermined amount of tip protrusion) is set to g. A shield cap 12 made of an insulating material is screwed into the male screw 3M. An O-ring 13 is attached between the shield cap 12 and the torch body 1. A collar 14 for preventing the tungsten electrode 7 from collapsing is disposed inside the anode fitting 3.
[0004]
By the way, in the case of the plasma welding torch, if the distance between the tip 7a of the tungsten electrode 7 and the end 11a of the small diameter hole 11 is long, it is difficult to start the arc even if the tip 7a of the tungsten electrode 7 is sharp. If the distance is too short, the tip 7a of the tungsten electrode 7 is consumed in a short time due to heat during processing (welding). For this reason, it is necessary to accurately position the tip 7a of the tungsten electrode 7 with respect to the end 11a of the small diameter hole 11.
[0005]
Therefore, prior to welding, the tip 7a of the tungsten electrode 7 is positioned using an electrode positioning jig (hereinafter referred to as “gauge”).
[0006]
FIG. 6 is a front sectional view of a conventional gauge 20. A small diameter portion 20 a and a large diameter portion 20 b are formed on the outer periphery of the gauge 20. The outer diameter of the small diameter portion 20a is a size that fits into the inner diameter of the female screw 3f. A hole 21 reaching the large diameter portion 20b side from the end surface (upper end surface) 20d on the small diameter portion 20a side is formed in the central portion. The inner diameter of the hole 21 is larger than the outer diameter of the tungsten electrode 7, and the bottom surface 22 is formed in a plane. And the distance from the step part 20c which is a connection part of the small diameter part 20a and the large diameter part 20b to the bottom face 22 is g.
[0007]
Next, a conventional procedure for positioning the tungsten electrode 7 will be described.
[0008]
FIG. 7 is a front cross-sectional view of the main part showing the positional relationship between the head part at the time of positioning and the conventional gauge 20. As shown in the figure, when positioning the tungsten electrode 7, the nozzle electrode 10 and the shield cap 12 are removed from the torch body 1, and the tip 7 a of the tungsten electrode 7 is projected from the end surface 3 a of the anode fitting 3. Then, the small-diameter portion 20a of the gauge 20 is inserted inside the female screw 3f, and the protruding amount of the tungsten electrode 7 is reduced until the gap formed between the step portion 20c and the end surface 3a becomes zero. That is, with the tungsten electrode 7 protruding slightly and the tip 7a of the tungsten electrode 7 in contact with the bottom surface 22, the end (lower end) 20s of the large diameter portion 20b is lightly pressed with a finger or the like. The cap 5 (see FIG. 5) is turned, and the tungsten electrode 7 is pulled in until the stepped portion 20c contacts the end surface 3a. When the step portion 20 c comes into contact with the end surface 3 a, the lock nut 8 is tightened to fix the cap 5 to the torch body 1.
[0009]
[Problems to be solved by the invention]
However, when the tungsten electrode is positioned using the gauge 20 described above, the protruding length of the tungsten electrode 7 does not become larger than g, but the protruding length of the tungsten electrode 7 is increased by returning the cap 5 too much. May be smaller than g. Further, when the lock nut 8 is tightened, the cap 5 is accidentally turned, and the protruding length may not be g.
[0010]
Therefore, an object of the present invention is to provide an electrode positioning jig (gauge) that can solve the above-described problems and can easily and surely set the protruding length of the tungsten electrode to an appropriate value.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the present invention according to claim 1 is directed to a positioning reference provided in the torch body for a plasma torch having a rod-like electrode and a torch body for holding the electrode so as to be movable in the longitudinal direction. In the electrode positioning jig of the plasma torch for setting the tip protrusion amount of the electrode from the predetermined amount,
A jig body that is brought into contact with the positioning reference from the tip side of the electrode during positioning,
The jig body is
An insertion hole into which the tip side of the electrode is inserted;
A first positioning portion that comes into contact with the positioning reference when the distal end side of the electrode is inserted into the insertion hole;
A second positioning portion that is disposed on the back side of the insertion hole, and the distance from the first positioning portion in the direction along the axis of the insertion hole is set to the predetermined amount;
A visual means for visualizing the second positioning portion from the outside of the jig body,
The insertion hole is a through-hole penetrating the jig body from the upper end surface on the insertion side of the electrode to the lower end surface ;
The second positioning portion is set at the exit of the through hole that is disposed exposed at the lower end surface of the jig body ,
The visual observation means is a lower end surface of the jig main body capable of visualizing a state in which the tip side of the electrode protrudes from the outlet of the through hole with respect to the jig main body .
The electrode positioning jig of the plasma torch is characterized in that.
[0012]
According to the first aspect of the present invention, since the second positioning portion disposed on the back side of the insertion hole can be viewed from the outside of the jig body by the visual means, the first positioning portion of the jig body is After making contact with the positioning reference of the torch main body, the position of the tip of the electrode with respect to the second positioning portion can be adjusted while visually confirming directly.
[0019]
And since an insertion hole is a through-hole which penetrates a jig | tool main body and the exit of this through-hole becomes a 2nd positioning part, this 2nd positioning part can be easily visually observed from the lower end surface of a jig | tool main body. Can do.
[0020]
The present invention according to claim 2 is the electrode positioning jig of the plasma torch according to claim 1, wherein the positioning reference is an end face of a cylindrical anode fitting constituting the torch body ,
The jig body has a small-diameter portion that is inserted between the electrode and the hollow portion of the anode fitting during positioning and is screwed into the anode fitting .
[0021]
According to the invention of claim 2 , it is not necessary to hold the entire electrode positioning jig by hand or push it with a finger by screwing the small diameter portion to the torch body side during positioning, and during positioning Since the electrode positioning jig can be prevented from moving unnecessarily, the positioning operation is easy and reliable.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or the same functions as those in FIGS. 5, 6, and 7 described above are denoted by the same reference numerals, and description thereof will be omitted as appropriate. 1 to 3 are reference examples serving as the basis of the embodiment of the present invention described in FIG. 4, but are referred to as Embodiments 1 and 2 for convenience.
[0023]
<Embodiment 1>
FIG. 1 is a front sectional view of an electrode positioning jig (gauge) 30 according to the present invention.
[0024]
The gauge 30 shown in the figure has a small diameter portion 30a on the rear end side (upper side) and a large diameter portion 30b as a jig body on the front end side (lower side). On the outer periphery of the small-diameter portion 30a, a male screw 3m that is screwed into the female screw 3f of the anode fitting 3 (see FIG. 5) is formed. The large-diameter portion 30b has a groove (visual means) 31 in which one side surface 31a is flush with the bottom surface (second positioning portion) 22 of the hole (insertion hole) 21. The shape of the horizontal cross section of the groove 31 (the cross section in the direction orthogonal to the axis of the hole 21) is substantially semicircular. A hole 32 having a diameter larger than that of the hole 21 is provided at the axial center of the hole (insertion hole) 21. Other dimensions are the same as those of the conventional gauge 20 shown in FIG.
[0025]
Next, a procedure for positioning the tungsten electrode 7 using the gauge 30 according to the present embodiment will be described.
[0026]
FIG. 2 is a front sectional view of a principal part showing a positional relationship between the head part and the gauge 30 at the time of positioning. In the present embodiment, a guide 33 whose inner diameter is fitted to the tungsten electrode 7 is disposed in the hole 32.
[0027]
When positioning the tungsten electrode 7, the nozzle electrode 10 and the shield cap 12 are previously removed from the torch body 1, the gauge 30 is screwed into the torch body 1, and the stepped portion (first positioning portion) 20 c of the gauge 30 is connected to the anode fitting 3. It is made to contact | abut to the end surface 3a. Then, the cap 5 is screwed into the torch body 1 while the position of the tip 7a of the tungsten electrode 7 with respect to the bottom surface 22 of the hole 21 is observed from the groove 31 of the gauge 30, and the protruding amount of the tungsten electrode 7 is increased little by little. This operation is continued until the tip 7a of the tungsten electrode 7 comes into contact with the bottom surface 22. After the contact, the cap 5 is fixed with the lock nut 8.
[0028]
According to the present embodiment, since the groove 30 is provided in the gauge 30 so that the bottom surface 22 of the hole 21 can be seen from the outside of the gauge 30, the tungsten electrode 7 is positioned with respect to the bottom surface 22 when the tungsten electrode 7 is positioned. Since it can be visually confirmed that the front end 7a is in contact, positioning accuracy can be significantly improved as compared with the conventional case. The groove 31 has one side 31 a is formed so as to be positioned on the bottom surface 22 flush with, moreover, is formed so as to penetrate the large diameter portion 30b in the diameter direction, the bottom surface 22 and the tip 7a of the tungsten electrode 7 are easy to see, and this also improves the positioning accuracy.
[0029]
Furthermore, according to this embodiment, since the gauge 30 is provided with the male screw 3m that is screwed into the female screw 3f of the anode fitting 3, the gauge 30 is held by hand when positioning the tip 7a of the tungsten electrode 7. There is no need to push it with a finger, and work is easy. In addition, since the gauge 30 does not move in the axial direction until the fixing of the cap 5 to the torch body 1 is completed, positioning of the tip is ensured.
[0030]
In addition, since the guide 33 is provided, the axis of the tungsten electrode 7 does not tilt with respect to the axes of the torch body 1 and the nozzle electrode 10.
[0031]
<Embodiment 2>
FIG. 3 shows a gauge 30 according to the second embodiment. In addition, the same thing as FIG. 1 or the thing of the same function attaches | subjects the same code | symbol, and abbreviate | omits description.
[0032]
In the present embodiment, a plug 40 from below is screwed into the shaft center of the gauge 30, and the upper end surface (second positioning portion) 40a of the plug 40 is set so that the distance from the step portion 20c is g. After the positioning, the plug 40 is prevented from rotating.
[0033]
According to the present embodiment, since it is not necessary to process the upper end surface 40a of the plug 40 and the lower side surface 31a of the groove 31, the gauge 30 can be easily manufactured as compared with the first embodiment. In addition, the groove width of the groove 31 can be increased, and the upper end surface 40a with which the tip 7a of the tungsten electrode 7 abuts can be easily seen. Further, the distance g can be set accurately. Since the distance g can be made variable, the gauge 30 can be versatile.
[0034]
Since the procedure for positioning the tungsten electrode 7 is the same as that in the first embodiment, description thereof is omitted.
[0035]
In the first and second embodiments described above, the groove 31 is provided in the radial direction so that the bottom surface 22 of the hole 21 and the upper end surface 40a of the plug 40 can be seen. However, as long as these are visible, the groove 31 is limited. It is not a thing. For example, the groove may be provided along the axis of the insertion hole, and the side surface on the back side of the insertion hole of the two side surfaces of the groove may be formed in the same plane as the bottom surface. You may make it provide a hole.
[0036]
<Embodiment 3>
FIG. 4 shows a gauge 30 according to the third embodiment. In addition, the same thing as FIG. 1 or the thing of the same function attaches | subjects the same code | symbol, and abbreviate | omits description.
[0037]
In the present embodiment, the axial length of the large diameter portion 30b is set to g, and the hole 21 penetrates the large diameter portion 30b in the axial direction and is exposed to the lower end surface 30s. Therefore, the outlet (second positioning portion) of the hole 21 is disposed on the lower end surface 30s. In the present embodiment, there is no portion corresponding to the bottom surface 22 of the above-described first embodiment and the upper end surface 40a of the plug 40 of the above-described second embodiment, but the bottom having the outlet 21a when the gauge 30 is viewed from the side. The end face 30s can be used instead of the bottom face 22 and the upper end face 40a.
[0038]
Note that the procedure for positioning the tungsten electrode 7 is substantially the same as in the first embodiment, and a description thereof will be omitted.
[0039]
According to the present embodiment, the configuration of the gauge 30 can be simplified as compared with the first and second embodiments.
[0040]
<Embodiment 4>
In the fourth embodiment, at least a part of the gauge 30 is constituted by a light transmitting member. The entire gauge 30 may be formed of a light transmitting member, and the light transmitting member is used only in a portion where the bottom surface 22 of the first embodiment and the upper end surface 40a of the plug 40 of the second embodiment can be seen through. May be.
[0041]
According to the present embodiment, there is no need to provide the groove 31 that was necessary in the first and second embodiments.
[0042]
【The invention's effect】
As described above, according to the present invention, the second positioning portion disposed on the back side of the insertion hole can be visually observed from the outside of the jig body by the visual means. After the positioning portion is brought into contact with the positioning reference of the torch body, the position of the tip of the electrode with respect to the second positioning portion can be adjusted while visually confirming directly by visual means. Work can be made easy and reliable.
[Brief description of the drawings]
FIG. 1 is a front sectional view of a gauge according to a first embodiment.
FIG. 2 is an operation explanatory diagram illustrating positioning of the tip of an electrode in the first embodiment.
FIG. 3 is a front sectional view of a gauge according to a second embodiment.
FIG. 4 is a front sectional view of a gauge according to a third embodiment.
FIG. 5 is a front sectional view of a head portion of a plasma welding torch.
FIG. 6 is a front sectional view of a conventional gauge.
FIG. 7 is an operation explanatory diagram illustrating positioning of the tip of an electrode by a conventional gauge.
[Explanation of symbols]
1 Torch body 3a Positioning standard (end face of anode fitting)
7 electrode (tungsten electrode)
7a Electrode tip 20c First positioning part (step part)
21 Insertion hole (hole)
21a Outlet 22 Second positioning portion (bottom surface)
30 Electrode positioning jig (gauge)
30a Small diameter part 30b Jig body (large diameter part)
31 Visual means (groove)
31a Side surface 40a of groove Second positioning portion (upper end surface)
g Predetermined amount (distance)

Claims (2)

Plasma for setting a protruding amount of the tip of the electrode from a positioning reference provided in the torch body to a predetermined amount for a plasma torch having a rod-like electrode and a torch body that holds the electrode so as to be movable in the longitudinal direction In the torch electrode positioning jig,
A jig body that is brought into contact with the positioning reference from the tip side of the electrode during positioning,
The jig body is
An insertion hole into which the tip side of the electrode is inserted;
A first positioning portion that comes into contact with the positioning reference when the distal end side of the electrode is inserted into the insertion hole;
A second positioning portion that is disposed on the back side of the insertion hole, and the distance from the first positioning portion in the direction along the axis of the insertion hole is set to the predetermined amount;
A visual means for visualizing the second positioning portion from the outside of the jig body,
The insertion hole is a through-hole penetrating the jig body from the upper end surface on the insertion side of the electrode to the lower end surface ;
The second positioning portion is set at the exit of the through hole that is disposed exposed at the lower end surface of the jig body ,
The visual observation means is a lower end surface of the jig main body capable of visualizing a state in which the tip side of the electrode protrudes from the outlet of the through hole with respect to the jig main body .
An electrode positioning jig for a plasma torch. The positioning reference is an end face of a cylindrical anode fitting constituting the torch body,
The jig body has a small-diameter portion that is inserted between the electrode and the hollow portion of the anode fitting during positioning and screwed into the anode fitting,
The electrode positioning jig of the plasma torch according to claim 1, wherein

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