JPS6321965Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an apparatus for semi-automatic welding using shielding gas. Generally, in this type of semi-automatic welding equipment, when the trigger installed on the welding torch is pulled, a self-resetting switch is activated.
As a result, the solenoid valve opens and shielding gas is supplied, and at the same time or after an appropriate time using a delay means such as a timer, the consumable electrode wire is fed and power is supplied to connect the electrode and the base material. Welding is performed by the arc generated during the welding process. By the way, in order to perform high-quality welding, it is mentioned that the arc generated between the electrode and the base metal should be completely blocked from the atmosphere using a shielding gas.
In the above case, when not welding, the gas passage from the solenoid valve installed in the shielding gas supply circuit to the torch side is gradually replaced with air that enters from the open part at the tip of the torch, and naturally the shielding gas is replaced with air as time passes. The proportion of cases where this happens will increase. Therefore, in order to perform high-grade welding economically and efficiently, it is necessary to consider the amount of shielding gas to be discharged before arc generation, depending on the replacement rate of shielding gas and air. However, if the time when the arc occurs is limited through the delay means as described above with respect to the time when the shielding gas is supplied, the delay means must be readjusted every time the replacement rate of the shielding gas and air changes as described above. Must be. Moreover, since this delay means, for example, a timer, is located at a location away from the welding torch, it is troublesome for the operator to go to the location where the timer is installed each time when readjusting, and this leads to wasted work time. It was on. However, if the delay means is adjusted so that the arc occurs after the shielding gas solenoid valve is activated and the gas passage from the solenoid valve to the tip of the torch is completely filled with shielding gas, the torch trigger can be activated. It is inefficient because it takes too long to generate an arc after operation, and in addition to this, if the exchange rate of shielding gas and air is small, more shielding gas than necessary will flow out. It was uneconomical.

Furthermore, a welding apparatus has been proposed that is equipped with a so-called gas check mechanism to adjust and set the flow rate of shielding gas during welding. In this case, it is customary to check with a gas flow meter that the gas flow rate has reached a predetermined value while adjusting the throttle valve that communicates with the gas supply path of the welding torch. It is carried out in an extremely short time of 3 seconds. For this reason, in the gas check mechanism provided in conventional equipment, a push button switch is provided in a so-called operation box formed separately from the welding torch, and the gas check mechanism operates in conjunction with the push button switch for a predetermined period of time.
In other words, a time limit switch was installed to open and close the solenoid valve, which turned off after a few seconds. However, with this type of gas check mechanism, the shielding gas and air in the gas passage on the torch side gradually change over time. In a welding device in which the replacement rate of air changes, it has been virtually impossible to eliminate the replaced air. Of course,
Expanding the function of the conventional gas check mechanism,
Adjusting the timer time of the time switch of the gas check mechanism in accordance with the replacement rate of the shielding gas and air is extremely troublesome because the operator must go to the location where the time switch is installed each time the adjustment is made.

An object of the present invention is to provide a semi-automatic gas-shielded arc welding apparatus that eliminates the above-mentioned conventional drawbacks.

The present invention will be explained in detail below with reference to the illustrated embodiments. In FIG. 1, 1 is a welding torch consisting of a torch neck 2, a torch body 3, a trigger 4, etc., and this torch 1 is equipped with appropriate connecting members such as a consumable electrode wire guide tube, a gas hose, and a control cable. 5 is installed. Reference numeral 6 designates a self-reciprocating switch, which generates an output signal by pulling the trigger 4. This output signal appropriately operates a shielding gas solenoid valve (not shown), a consumable electrode wire feeder, and a welding power source to perform welding. will be carried out. 7
7 is a self-holding switch connected to the shielding gas electromagnetic valve (not shown), and by operating this self-holding switch 7, the shielding gas can be appropriately discharged regardless of welding. Furthermore, since the switch 7 is of a self-holding type, the shielding gas can be allowed to flow out for any desired period of time until the return operation is performed. In addition, since the self-holding switch 7 is installed in the torch main part 3, the worker does not need to go to the installation location of other equipment even when only the shielding gas is to be discharged, and can be operated from hand, improving work efficiency. good. Particularly when performing high-grade welding, the operation of draining the shielding gas before welding is frequently performed, so switch 7 is
Since the switch 7 is self-holding type, the switch 7 is easy to operate.
After turning on, the shielding gas can be allowed to flow out for an arbitrary period of time until it is turned off again. For example, when letting shield gas flow out for 2 to 3 minutes, if the switch that operates the shield gas solenoid valve is a self-resetting switch such as a push button type, it is necessary to continue pressing this switch while the shield gas is flowing out. However, since the shielding gas electromagnetic valve is opened and closed by a self-holding switch as described above, the operator can perform other tasks except when opening and closing the switch. Of course, if the top of the self-holding switch is arranged so that it does not protrude from the surface of the torch body, there is no risk that the switch will be operated other than when necessary.

As described above, according to the present invention, a manual switch for opening and closing the shielding gas solenoid valve is provided on the torch body, making it easy to operate, and since the switch is a self-holding type switch. The outflow time of the shielding gas can be selected as appropriate, and when the outflow time of the shielding gas is desired to be extended, the operator can perform other tasks while the shielding gas is outflowing, which improves work efficiency compared to conventional methods. Improved and economical.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a main part showing an embodiment of the present invention. 1...Torch, 3...Torch body, 7...Self-holding switch.

Claims (1)

[Claims for Utility Model Registration] 1. A torch having a welding trigger and a shielding gas supply source are connected via a solenoid valve, and in addition to the trigger switch, there is also a manual switch for opening and closing the solenoid valve. A semi-automatic gas shielded arc welding device comprising a self-holding switch disposed in the main body of the torch. 2. The semi-automatic gas-shielded arc welding apparatus according to claim 1, wherein the self-holding switch is arranged so that its top does not protrude from the surface of the torch body.