CN218396410U - Projection welding electrode - Google Patents

Abstract

The utility model belongs to the welding field discloses a projection welding electrode, it includes: the electrode column shell comprises a column shell closed end, a column shell open end and a column shell cavity, the column shell cavity comprises a cavity sliding area and a cavity pressure maintaining area, the cavity sliding area and the column shell open end are sequentially communicated, and a column shell air inlet communicated with the column shell cavity is formed in the outer wall of the electrode column shell; and the electrode pin shaft can be inserted in the cavity sliding area in a sliding manner, the axial inner end of the electrode pin shaft is formed into a pin shaft inserting end, the axial outer end of the electrode pin shaft is formed into a pin shaft positioning end capable of extending out of the opening end of the column shell, a pin shaft flange part is formed on the outer peripheral wall of the pin shaft inserting end, and a flange part vent hole communicating the cavity sliding area and the cavity pressure maintaining area is formed in the pin shaft flange part. The utility model discloses a projection welding electrode can avoid appearing the welding reposition of redundant personnel phenomenon, and need not dismantle alright carry out the coping and adjust and the laminating degree of mating electrode, can ensure welding strength and quality, improves production efficiency, increase of service life.

Description

Projection welding electrode

Technical Field

The utility model relates to the field of welding technique, specifically, relate to a projection welding electrode.

Background

Projection welding is an efficient welding method capable of simultaneously performing multi-point welding, has no other consumption except electric energy, and is widely applied to manufacturing of thin plate parts. For example, the nut projection welding is to position a nut and a thin plate part with a positioning pin in a lower electrode, and then to weld the nut to a specified position of the thin plate part by pressing down the nut with an upper electrode.

However, in the projection welding process of the conventional nut, referring to fig. 6, the positioning pin 66 in the conventional electrode 600 may contact the electrode holder 61 through the spring 63 connected to the bottom thereof, thereby causing a welding shunt phenomenon, which may affect the welding strength of the nut, and even burn the thread in a severe case. For this purpose, the conventional electrode 600 is further provided with an insulating spacer 62 for spacing the spring 63 from the electrode holder 61. However, the insulating gasket 62 is easily damaged by repeated pressing of the spring 63 during the welding process, so that the spring 63 still has a contact risk with the electrode holder 61, and the insulating gasket 62 is installed in the closed cavity, and is difficult to find after being damaged, thereby easily causing batch quality accidents.

On the other hand, after a certain number of nuts are welded, an oxide film layer affecting the welding quality is formed on the surface of the electrode cap 64, and thus it is necessary to polish it to remove the oxide film layer. When the spring 63 is compressed to the limit position, the top end of the positioning pin 66 still extends out of the electrode cap 64, so that before the electrode cap 64 is ground, the electrode cap 64 must be detached first to take out the positioning pin 66, and then the electrode cap 64 and the upper electrode are reassembled after grinding is completed, and meanwhile, the degree of adhesion between the electrode cap 64 and the upper electrode needs to be readjusted, so that the welding efficiency is greatly influenced.

SUMMERY OF THE UTILITY MODEL

At least one defect or not enough to prior art's the aforesaid, the utility model provides a projection welding electrode can avoid appearing the welding reposition of redundant personnel phenomenon, and need not dismantle alright carry on the coping and adjust and mating electrode's laminating degree to ensure welding strength and quality, improve production efficiency, extension electrode life.

In order to achieve the above object, the utility model provides a projection welding electrode, projection welding electrode includes:

the electrode column shell comprises a column shell closed end, a column shell open end and a column shell cavity formed between the column shell closed end and the column shell open end, the column shell cavity comprises a cavity slippage area and a cavity pressure maintaining area, the cavity slippage area and the column shell open end are sequentially communicated, and a column shell air inlet communicated with the column shell cavity is formed in the outer wall of the electrode column shell; and

the electrode pin shaft can be inserted into the cavity sliding area in a sliding mode, the axial inner end of the electrode pin shaft is formed into a pin shaft inserting end, the axial outer end of the electrode pin shaft is formed into a pin shaft positioning end capable of extending out of the opening end of the column shell, a pin shaft flange portion is formed on the outer peripheral wall of the pin shaft inserting end, and a flange portion vent hole communicated with the cavity sliding area and the cavity pressure maintaining area is formed in the pin shaft flange portion.

Optionally, the inner diameter of the cavity pressure-retaining area is gradually reduced from outside to inside along the axial direction, and the outer diameter of the pin shaft flange portion is at least larger than the minimum inner diameter of the cavity pressure-retaining area.

Optionally, the cross sectional area of the cavity pressure maintaining area is smaller than that of the cavity sliding area, and a stopping step portion for stopping the pin shaft flange portion to limit the electrode pin shaft from sliding to the cavity pressure maintaining area is formed at a joint of the cavity sliding area and the cavity pressure maintaining area.

Optionally, a stopping protrusion for stopping the pin shaft flange part to limit the electrode pin shaft from sliding to the cavity pressure retaining area is formed on the inner peripheral wall of the cavity at the boundary area between the cavity sliding area and the cavity pressure retaining area.

Optionally, the column casing air inlet hole is formed from the outer circumferential wall of the electrode column casing inwards through the inner circumferential wall of the cavity sliding area.

Optionally, the pin shaft flange part is formed with a plurality of the flange part vent holes arranged at equal intervals in sequence along the circumferential direction.

Optionally, the projection welding electrode comprises an indwelling gas pipe joint inserted into the column shell gas inlet hole.

Optionally, the electrode column shell comprises an inner sleeve column and an outer sleeve column, the outer sleeve column comprises an outer sleeve column closed end, an outer sleeve column open end and an outer sleeve column cavity formed between the outer sleeve column closed end and the outer sleeve column open end, and the inner sleeve column comprises two inner sleeve column open ends and an inner sleeve column cavity formed between the two inner sleeve column open ends;

the outer sleeve connecting column cavity and the inner sleeve connecting column cavity jointly define the column shell cavity.

Optionally, the electrode pin can slide inward to a position where the pin locating end does not extend out of the open end of the column casing.

Optionally, the projection welding electrode includes an insulating bush sleeved between an inner peripheral wall of the inner sleeve column cavity and an outer peripheral wall of the electrode pin shaft.

The utility model discloses in, especially mark off the cavity in the column casing cavity of projection welding electrode and slide district and cavity and protect the district to guarantee through setting up flange portion air vent that the cavity slides the district and the cavity keeps the district to communicate all the time, when introducing outside gas from the column casing inlet port like this, just enable to be used in the axial of round pin axle flange portion on the gas pressure of terminal surface enough drive electrode round pin axle to slide towards the column casing open end. In the projection welding process, as long as the gas pressure acting on the axial inner end face of the flange part of the pin shaft is kept to be large and stable enough, the positioning end of the pin shaft can be ensured to be fixed outside the opening end of the column shell all the time. Therefore, connecting pieces such as springs do not need to be arranged between the electrode pin shaft and the electrode column shell, so that the phenomenon of welding shunting caused by contact between the electrode pin shaft and the electrode column shell can be avoided, and the welding strength and quality are ensured.

When the gas circuit is cut off, the electrode pin shaft can be completely retracted into the cavity of the column shell due to the fact that no connecting piece such as a spring is limited, so that the electrode pin shaft can be ground for the inner sleeved column without disassembling the projection welding electrode under the condition that the electrode column shell comprises the inner sleeved column and the outer sleeved column, the grinding file can be placed between the inner sleeved column and the paired electrode during grinding, the inner sleeved column and the paired electrode are ground synchronously through rotation of the file, the fit degree of the inner sleeved column and the paired electrode after grinding is effectively guaranteed, time delay of projection welding operation can be shortened, production efficiency is improved, electrode structure abrasion caused by repeated disassembly and assembly of the projection welding electrode can be reduced, and the service life of the electrode is prolonged.

Other features and advantages of the present invention will be described in detail in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic view of a projection welding electrode according to an embodiment of the present invention, wherein the illustrated electrode pin is fully received in the column housing cavity;

FIG. 2 is another schematic view of the projection welded electrode of FIG. 1, wherein the pin locating end of the electrode pin is shown extending beyond the open end of the column housing;

FIG. 3 is a perspective view of the electrode pin of FIG. 1;

FIG. 4 is a schematic view of a nut and sheet member being welded using a mating electrode and the projection welding electrode of FIG. 2;

FIG. 5 is a schematic view of the simultaneous dressing of a counter electrode and the projection welding electrode of FIG. 1 using a dressing file;

fig. 6 is a schematic diagram of a conventional electrode.

Description of reference numerals:

100. projection welding electrode

11. 12 electrode pin shafts of electrode column shell

13. Keep somewhere trachea joint 14 insulating bush

111. Inner sleeve 112 and outer sleeve

113. Column casing cavity 121 pin shaft flange part

113a cavity sliding region 113b cavity pressure retaining region

121a flange vent hole

200. Counter electrode 300 thin plate

400. Nut 500 grinding file

600. Existing electrodes

61. Electrode holder 62 insulating spacer

63. Spring 64 electrode cap

65. Insulation sleeve 66 locating pin

Detailed Description

The following describes in detail embodiments of the present invention with reference to the accompanying drawings. It is to be understood that the description herein is only intended to illustrate and explain embodiments of the present invention, and is not intended to limit embodiments of the present invention.

It should be noted that, in the present invention, the embodiments and features of the embodiments may be combined with each other without conflict.

In the embodiments of the present invention, unless otherwise specified, the use of directional terms such as "upper, lower, top, bottom" and "upper" are generally used with respect to the orientation shown in the drawings or the positional relationship of the components with respect to each other in the vertical, vertical or gravitational direction.

The invention will be described in detail below with reference to the accompanying drawings in conjunction with exemplary embodiments.

As shown in fig. 1 to 3, an exemplary embodiment of the present invention provides a projection welding electrode 100 including an electrode column case 11 and an electrode pin 12.

Wherein, the axial both ends of electrode column shell 11 form column shell closed end and column shell open end respectively, are formed with column shell cavity 113 between column shell closed end and the column shell open end. The column shell cavity 113 comprises a cavity sliding area 113a and a cavity pressure maintaining area 113b, and the cavity pressure maintaining area 113b, the cavity sliding area 113a and the open end of the column shell are sequentially communicated. The outer wall of the electrode column shell 11 is formed with a column shell air intake hole communicating with the column shell cavity 113, and when projection welding is performed using the projection welding electrode 100, gas, such as compressed air, can be introduced into the column shell cavity 113 from the outside through the column shell air intake hole.

The electrode pin 12 is slidably inserted into the cavity sliding region 113a, and an axial inner end of the electrode pin 12 is formed as a pin insertion end and an axial outer end is formed as a pin positioning end. When the projection welding electrode 100 is assembled, the pin insertion end of the electrode pin 12 is inserted into the cavity slip region 113a through the open end of the cylindrical shell. By the electrode pin 12 sliding in the cavity sliding region 113a, the pin positioning end can extend out of the open end of the column casing, and preferably, the pin positioning end can also be fully retracted into the cavity sliding region 113a without extending out of the open end of the column casing. Further, the outer peripheral wall of the pin insertion end is formed with a pin flange portion 121, and the pin flange portion 121 is formed with a flange portion vent hole 121a communicating the cavity sliding region 113a and the cavity pressure retaining region 113b, and the number of the flange portion vent holes 121a may be plural.

After the outside air enters the column shell cavity 113 through the column shell air inlet hole, the outside air can enter the cavity sliding area 113a and the cavity pressure maintaining area 113b all the time due to the existence of the flange vent hole 121 a. In this way, even in the case where the electrode pin 12 is at the axially innermost end position within the cavity slip region 113a, the axially inner end face of the pin flange portion 121 can be subjected to gas pressure by introducing external gas. As for the pin shaft flange portion 121, the pressures borne by the respective positions are the same, and based on the structure of the pin shaft flange portion 121, the area of the axially outer end surface thereof is smaller than the area of the axially inner end surface thereof, so that the gas pressure borne by the axially inner end surface of the pin shaft flange portion 121 is inevitably larger than the gas pressure borne by the axially outer end surface thereof, and therefore, as long as the pressure for introducing external gas and the weight of the electrode pin shaft 12 are reasonably set, the gas pressure borne by the axially inner end surface of the pin shaft flange portion 121 can be larger than the sum of the gas pressure borne by the axially outer end surface thereof and the gravity borne by the electrode pin shaft 12, so that the electrode pin shaft 12 is driven to slide toward the opening end of the column casing under the condition of introducing external gas, and the condition that the electrode pin shaft 12 does not slide but ventilation occurs is avoided.

As can be seen from the above, in the exemplary embodiment, the cavity sliding region 113a and the cavity pressure maintaining region 113b are defined in the column casing cavity 113 of the projection welding electrode 100, and the flange vent holes 121a are provided to ensure that the cavity sliding region 113a and the cavity pressure maintaining region 113b are always communicated with each other, so that when external air is introduced from the column casing air inlet hole, the gas pressure acting on the axial inner end surface of the pin shaft flange 121 is sufficient to drive the electrode pin shaft 12 to slide toward the open end of the column casing. In the projection welding process, as long as the gas pressure acting on the axial inner end face of the flange part of the pin shaft is kept to be large and stable enough, the positioning end of the pin shaft can be ensured to be fixed outside the opening end of the column shell all the time. Therefore, connecting pieces such as springs do not need to be arranged between the electrode pin shaft 12 and the electrode column shell 11, so that the phenomenon of welding shunting caused by contact between the electrode pin shaft 12 and the electrode column shell 11 can be avoided, and the welding strength and quality are ensured.

To ensure that the external gas can enter the cavity pressure maintaining region 113b and the axial inner end surface of the pin shaft flange portion 121 bears the gas pressure, it is required to define that when the electrode pin shaft 12 is located at the axial innermost end position in the cavity sliding region 113a, the axial inner end surface of the pin shaft flange portion 121 does not adhere to the bottom surface of the cavity pressure maintaining region 113b. Otherwise, gas cannot be introduced between the axial inner end surface of the pin shaft flange portion 121 and the bottom surface of the cavity pressure maintaining region 113b, so that the axial inner end surface of the pin shaft flange portion 121 cannot bear the gas pressure.

In some embodiments, which will be described below, it is ensured that the axially inner end surface of the flange portion 121 of the pin shaft can bear the gas pressure, which will be described below.

In an alternative or preferred embodiment, referring to fig. 1, the inner diameter of the cavity pressure-retaining region 113b is set to be gradually reduced from the outside to the inside in the axial direction, and the outer diameter of the pin shaft flange portion 121 is set to be at least larger than the minimum inner diameter of the cavity pressure-retaining region 113b. With this structure, as shown in the drawing, when the electrode pin 12 is located at the axially innermost end position in the cavity slipping region 113a, the cavity peripheral wall region in the cavity pressure holding region 113b, in which the inner diameter of the peripheral wall is substantially the same as the outer diameter of the pin flange portion 121, can stop the electrode pin 12 from further axially moving inward, so that an air intake space is always left between the axially inner end surface of the pin flange portion 121 and the bottom surface of the cavity pressure holding region 113b, so that the axially inner end surface of the pin flange portion 121 can bear the gas pressure.

In an alternative or preferred embodiment (not shown), the cross-sectional area of the cavity dwell region 113b is set smaller than the cross-sectional area of the cavity sliding region 113a, and it is noted that it is not necessary to set the inner diameter of the cavity dwell region 113b to be gradually reduced from the outside to the inside in the axial direction. In addition, a stopping step part is formed at the joint of the cavity sliding area 113a and the cavity pressure maintaining area 113b, when the electrode pin shaft 12 is located at the axial innermost end position in the cavity sliding area 113a, the axial inner end surface of the pin shaft flange part 121 is abutted against the stopping step part, and through reasonably setting the position of the flange part vent hole 121a, the flange part vent hole 121a is not influenced to be communicated with the cavity sliding area 113a and the cavity pressure maintaining area 113b, so that the electrode pin shaft 12 can be stopped from further moving axially inwards, and gas can enter the cavity pressure maintaining area 113b.

In an alternative or preferred embodiment (also not shown), the stop protrusion is directly formed on the inner peripheral wall of the cavity at the boundary region between the cavity slip region 113a and the cavity pressure holding region 113b, that is, the stop protrusion is formed on the inner peripheral wall of the cylindrical shell cavity 113 to divide the cavity slip region 113a and the cavity pressure holding region 113b in the cylindrical shell cavity 113. Note that it is not necessary at this time to set the cross-sectional area of the cavity holding pressure region 113b smaller than the cross-sectional area of the cavity slip region 113a. When the electrode pin 12 is located at the axially innermost end position in the cavity slipping area 113a, the axially inner end surface of the pin flange 121 abuts against the stop boss, and the flange vent 121a is reasonably arranged, so that the flange vent 121a is not influenced to communicate the cavity slipping area 113a with the cavity pressure maintaining area 113b, and the electrode pin 12 can be stopped from further axially moving inwards, and gas can enter the cavity pressure maintaining area 113b.

It can be seen that the three embodiments listed above all ensure that the axial inner end face of the pin shaft flange portion 121 can bear the gas pressure.

Since the outside air introduced from the column shell air intake hole can finally enter the cavity pressure maintaining region 113b, there are various schemes for setting the specific position of the column shell air intake hole. For example, the column casing air intake holes may be formed from the outer peripheral wall of the electrode column casing 11 inwardly through the inner peripheral wall of the cavity slipping region 113a, i.e., the column casing air intake holes directly communicate with the cavity slipping region 113a. Alternatively, the case air intake holes may be formed from the outer circumferential wall of the electrode case 11 to penetrate the inner circumferential wall of the cavity pressure maintaining region 113b, that is, the case air intake holes directly communicate with the cavity pressure maintaining region 113b.

In an alternative or preferred embodiment, the number of the flange vent holes 121a is set to be plural, so that the gas diffusion speed can be increased, and the response speed of the electrode pin 12 to the sliding motion can be increased.

Further, the plurality of flange vent holes 121a may be arranged on the pin shaft flange 121 at regular intervals in sequence along the circumferential direction, so that the electrode pin shaft 12 is stressed in a balanced manner in the process of sliding toward the open end of the cylindrical shell, thereby preventing the electrode pin shaft from deviating from the central axis and sliding to extrude and rub against the inner peripheral wall of the cylindrical shell cavity 113, and ensuring smooth sliding.

In addition, when the insulating bush 14 is sleeved between the inner peripheral wall of the cavity sliding area 113a and the outer peripheral wall of the electrode pin shaft 12 to better prevent welding shunting, the plurality of flange part vent holes 121a are arranged on the pin shaft flange part 121 at equal intervals along the circumferential direction in turn, so that the electrode pin shaft 12 can be prevented from deviating from the central axis to slide integrally and extruding and rubbing with the inner peripheral wall of the insulating bush 14, the insulating bush 14 is prevented from being damaged, and the service life of the projection welding electrode 100 is prolonged.

In an alternative or preferred embodiment, projection welding electrode 100 further comprises an indwelling gas line connector 13 inserted into the column housing inlet. Before projection welding, the outlet pipe of the external gas source equipment can be connected with the indwelling gas pipe joint 13 so as to introduce gas into the projection welding electrode 100, and after the projection welding is completed, the outlet pipe of the external gas source equipment can be quickly disconnected from the indwelling gas pipe joint 13. Therefore, the setting of the indwelling gas pipe joint 13 can shorten the preparation time before projection welding and the recovery time after projection welding, which is advantageous for improving the work efficiency of the whole projection welding process.

In an alternative or preferred embodiment, as shown in fig. 1 and 2, the electrode column casing 11 includes an inner landing leg 111 and an outer landing leg 112. The outer jacket leg 112 includes an outer jacket leg closed end, an outer jacket leg open end, and an outer jacket leg cavity formed between the outer jacket leg closed end and the outer jacket leg open end. The inner telescoping post 111 includes two inner telescoping post open ends and an inner telescoping post cavity formed between the two inner telescoping post open ends. The closed end of the outer sleeve joint column is formed into the closed end of the column shell, one of the open ends of the two inner sleeve joint columns is inserted into the cavity of the outer sleeve joint column, the other open end of the two inner sleeve joint columns extends out of the cavity of the outer sleeve joint column as the open end of the column shell, and the cavity of the outer sleeve joint column and the cavity of the inner sleeve joint column jointly define the cavity 113 of the column shell.

Based on the above setting, when letting in the outside gas in to column casing cavity 113, electrode pin 12 can slide towards the column casing open end, and until the outer terminal surface of the axial of round pin axle flange portion 121 and the interior grafting post open end butt that is located the axial inboard, electrode pin axle 12 just can't further axial move outward. At this point, the pin locating end has been extended out of the open end of the column casing, and the electrode pin 12 is fixed in position by maintaining the gas pressure acting on the axially inner end face of the pin flange portion stable.

In addition, in the present embodiment, when the projection welding electrode 100 is provided with the aforementioned insulating bush 14, the insulating bush 14 is sleeved between the inner peripheral wall of the inner sleeve column cavity and the outer peripheral wall of the electrode pin 12, so as to better prevent welding shunting.

When the projection welding electrode 100 of the present exemplary embodiment is used for cutting off the gas path, the electrode pin 12 can be completely received in the cylindrical shell cavity 113 without limitation of a connecting member such as a spring, so that, referring to fig. 5, in the case that the electrode cylindrical shell 11 includes the inner sleeve post 111 and the outer sleeve post 112, the inner sleeve post 111 can be ground without disassembling the projection welding electrode 100, and the grinding file 500 can be placed between the inner sleeve post 111 and the mating electrode 200 during grinding, and the inner sleeve post 111 and the mating electrode 200 are synchronously ground by rotation of the grinding file 500, so that the degree of attachment of the inner sleeve post 111 and the mating electrode 200 after grinding is effectively ensured, thereby shortening the delay time of projection welding operation, improving the production efficiency, reducing the wear of the electrode structure caused by repeatedly disassembling and assembling the projection welding electrode 100, and prolonging the service life of the electrode.

In performing the nut projection welding, referring to fig. 4, the projection welding electrode 100 of the present exemplary embodiment is generally used as a lower electrode, and the counter electrode 200 is correspondingly used as an upper electrode that is paired with the projection welding electrode 100, and by using both of them in cooperation, the nut 400 can be welded to a specified position of the sheet member 300.

Above has described in detail the optional implementation way of the embodiment of the present invention with reference to the attached drawings, however, the embodiment of the present invention is not limited to the specific details in the above implementation way, and in the technical idea scope of the embodiment of the present invention, it can be to the technical solution of the embodiment of the present invention carry out multiple simple variants, and these simple variants all belong to the protection scope of the embodiment of the present invention.

It should be noted that, in the above-mentioned embodiments, the various technical features described in the above-mentioned embodiments can be combined in any suitable way without contradiction, and in order to avoid unnecessary repetition, the embodiments of the present invention do not separately describe various possible combinations.

In addition, various different implementation manners of the embodiments of the present invention can be combined arbitrarily, and as long as it does not violate the idea of the embodiments of the present invention, it should be considered as the disclosure of the embodiments of the present invention.

Claims (10)

1. A projection welding electrode, characterized in that the projection welding electrode (100) comprises:

the electrode column shell (11) comprises a column shell closed end, a column shell open end and a column shell cavity (113) formed between the column shell closed end and the column shell open end, wherein the column shell cavity (113) comprises a cavity sliding area (113 a) and a cavity pressure maintaining area (113 b), the cavity sliding area (113 a) and the column shell open end are sequentially communicated, and a column shell air inlet hole communicated with the column shell cavity (113) is formed in the outer wall of the electrode column shell (11); and

the electrode pin shaft (12) is inserted into the cavity sliding area (113 a) in a sliding manner, the axial inner end of the electrode pin shaft (12) is formed into a pin shaft inserting end, the axial outer end of the electrode pin shaft is formed into a pin shaft positioning end capable of extending out of the opening end of the column shell, a pin shaft flange part (121) is formed on the outer peripheral wall of the pin shaft inserting end, and a flange part vent hole (121 a) communicating the cavity sliding area (113 a) and the cavity pressure maintaining area (113 b) is formed in the pin shaft flange part (121).

2. A projection welding electrode according to claim 1, characterized in that the cavity pressure retaining area (113 b) has an inner diameter that tapers from the outside to the inside in the axial direction, and the outer diameter of the pin shaft flange portion (121) is at least larger than the smallest inner diameter of the cavity pressure retaining area (113 b).

3. The projection welding electrode according to claim 1, wherein the cross-sectional area of the cavity pressure-retaining region (113 b) is smaller than the cross-sectional area of the cavity sliding region (113 a), and a stopping step portion for stopping the pin shaft flange portion (121) to limit the electrode pin shaft (12) from sliding to the cavity pressure-retaining region (113 b) is formed at the junction of the cavity sliding region (113 a) and the cavity pressure-retaining region (113 b).

4. The projection welding electrode according to claim 1, wherein a stopping protrusion for stopping the pin shaft flange part (121) to limit the electrode pin shaft (12) from sliding to the cavity pressure-retaining region (113 b) is formed on the inner peripheral wall of the cavity at the boundary region of the cavity sliding region (113 a) and the cavity pressure-retaining region (113 b).

5. A projection welding electrode according to claim 1, characterized in that the cartridge inlet hole is formed from the outer circumferential wall of the electrode cartridge (11) inwardly through the inner circumferential wall of the cavity glide region (113 a).

6. A projection welding electrode according to claim 1, characterized in that said pin shaft flange portion (121) is formed with a plurality of said flange portion vent holes (121 a) arranged at equal intervals in the circumferential direction in order.

7. A projection welding electrode according to claim 1, characterized in that said projection welding electrode (100) comprises an indwelling gas tube connector (13) inserted into said column casing gas inlet hole.

8. A projection welding electrode according to any one of claims 1 to 7, characterized in that the electrode column casing (11) comprises an inner stud (111) and an outer stud (112), the outer stud (112) comprising an outer stud closed end, an outer stud open end and an outer stud cavity formed between the outer stud closed end and the outer stud open end, the inner stud (111) comprising two inner stud open ends and an inner stud cavity formed between the two inner stud open ends;

the closed end of the outer sleeve connecting column is formed into the closed end of the column shell, one of the open ends of the two inner sleeve connecting columns is inserted into the cavity of the outer sleeve connecting column, the other open end of the two inner sleeve connecting columns is used as the open end of the column shell and extends out of the cavity of the outer sleeve connecting column, and the cavity of the outer sleeve connecting column and the cavity of the inner sleeve connecting column jointly define the cavity (113) of the column shell.

9. A projection welding electrode according to claim 8, characterized in that the electrode pin (12) is slidable inwards so that the pin locating end does not protrude outside the open end of the stud housing.

10. A projection welding electrode according to claim 8, characterized in that the projection welding electrode (100) comprises an insulating bush (14) sleeved between the inner circumferential wall of the inner sleeve stud cavity and the outer circumferential wall of the electrode pin (12).

Images