JPH0573514B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention provides a fillet welding method for automatically welding a plurality of intermittent welds of a lap fillet joint of thin plates constituting a vehicle deck of a car carrier, etc. Regarding.

[Conventional technology]

Conventionally, when welding multiple intermittent welds of overlap fillet joints of thin plates constituting the vehicle deck of a car carrier, etc., the positions where the joints should be welded, that is, the welds, were marked according to the design drawings, and each marked The welded parts are welded by hand or by a semi-automatic carbon dioxide arc welding machine.

[Problem that the invention seeks to solve]

However, in manual welding or welding using a semi-automatic welding machine, there is a limit to the rod movement speed, making it difficult to perform short-leg welding with little distortion, and the total length of the weld is extremely long. There are problems in that it is extremely difficult to maintain concentration during welding work, it is impossible to improve work efficiency, and it is impossible to maintain uniform quality of all welded parts.

Therefore, in this invention, it is possible to automatically weld multiple intermittent welds of lap fillet joints of thin plates,
The technical challenges are to improve work efficiency and maintain and improve the quality of welded parts.

[Means for solving problems]

The present invention has been made with the above points in mind, and provides a fillet welding method for automatically welding a plurality of intermittent welds of a lap fillet joint formed by stacking thin plates on a base material. , a welding torch is attached to a traveling truck that runs along the welding line of the joint, and the position of the tip of the torch is controlled by a V-shaped grooved roller provided on the truck and rolling on the upper edge of the welded portion of the thin plate. The welding speed determined by the leg length and the welding time of each welded part and the non-welded time of the non-welded part derived from the length of each welded part and the length of the non-welded part are set respectively by the welding timer and The fillet welding method is characterized in that time is measured by a welding pause timer, and a welding power source energizes the torch for a period of time measured by the welding timer, and stops energizing the torch for a period of time measured by the welding pause timer. .

[Effect]

Therefore, according to the present invention, the V-shaped grooved roller provided on the traveling carriage rolls on the upper edge portion of the thin plate of the lap fillet joint, and the rolling of the roller causes the joint at the tip of the welding torch to roll. The position of the welding part is traced, and the truck travels while the tip of the welding torch is always held at a constant tracing position with respect to the welding part, and welding is performed.

At this time, the welding time of each welded part and the non-welded time of the non-welded part are derived in advance from the welding speed determined by the leg length and the length of each welded part and the length of the non-welded part, and each derived welding time The welding timer and the welding pause timer respectively measure the non-welding time, the welding power supply energizes the welding torch while the welding timer is counting time, and the welding torch is de-energized while the welding pause timer is counting time. Automatic welding of intermittent welds of joints is performed.

〔Example〕

Next, the present invention will be described in detail with reference to drawings showing one embodiment thereof.

First, in FIGS. 1 and 2, 1 is a base material, 2a and 2b are two thin plates stacked on the base material 1 to form a lap fillet joint 3, and 4 is four wheels 5.
6 is a welding torch attached to the front end of the upper surface of the truck 4 by a mounting member 7, and 8a and 8b are the truck 4. Support arms 10a and 10b are fixed to the front and rear surfaces of the vehicle by bolts 9 and have left ends extending to the left of the truck 4, respectively, and V-shaped grooves 10a and 10b are rotatably supported at the left ends of both support arms 8a and 8b, respectively. This roller rolls on the upper edge of the welded portion of both thin plates 2a and 2b, and holds the tip of the torch 6 at a predetermined tracing position relative to the welded portion of the joint 3.

Note that B in FIG. 1 is a weld bead.

Then, as shown in FIG.
The first welded part W1 of 1, the first non-welded part N1 of length L2, the second welded part W2 of length L3, and the second non-welded part N2 of length L2 are two welding cycles,
FIG. 4, which shows the configuration of a welding control circuit for welding such a joint 3 when the welding cycle is repeatedly formed, will be described.

In the figure, 11a and 11b are first and second terminals connected to both ends of the AC power supply, 12 is a fuse whose one end is connected to the first terminal 11a, and 13 is a fuse whose both ends are connected to the other end of the fuse 12 and the second terminal. A power indicator lamp is connected to 11b, 14 is a normally closed limit switch whose one end is connected to the other end of fuse 12 and turns off when all welding is completed, 15 is a normally closed push switch for stopping, and 16 is a normally open push switch for starting. , 17 is both push switch 15,1
A first relay 18 is connected to the other end of the limit switch 14 through a series circuit of 6, a normally open first contact for self-holding of the first relay 17 connected in parallel to the push switch 16, and 19 has one end connected to the fuse 12.
The normally open second contact of the first relay 17 is connected to the other end, 20 is an indicator lamp whose both ends are connected to the other end of the contact 19 and the second terminal 11b, and 21 is the off time of the second timer relay, which will be described later. Normally closed first contact 22 for
a first connected in parallel to the indicator lamp 20 via
This is a timer relay, and after one welding cycle is completed, it resets each part to the start state of the next cycle.

23 is a second relay connected in parallel to the indicator lamp 20 via a normally open contact 24 for ON time limit of the first timer relay 21; 25 is a second timer relay whose one end is connected to the other end of the contact 19; The normally closed second contact 26 for off time limit is a third relay, one end of which is connected to the other end of the contact 25 via the normally open first contact 27 of the relay 26, and the other end is connected to the second terminal 11b. It is connected to the.

28 is a normally open contact of a sixth relay, which will be described later, which is connected in parallel to the contact 27, and 29 is a normally closed first contact 30 for off-time of a fourth timer relay, which will be described later, and whose one end is connected to the other end of the contact 19. A series circuit of the normally open second contact 31 of the fourth timer relay, 32 a fourth relay whose both ends are connected to the other end of the series circuit 29 and the second terminal 11b, and 33 a common terminal 33a connected to the contact 1
It is a mode changeover switch connected to the other end of 9, and the first to third changeover terminals 33b, 33c, 33d.
The terminals 33b to 33d serve as mode switching terminals of "auto", "off", and "manual", respectively, and the second switching terminal 33c is open.

34 is a normally open first contact of a seventh relay, which will be described later, and whose one end is connected to the first switching terminal 33b, and 35 is contact 3.
4, a normally closed contact of a fourth relay 32 connected in parallel to
A fifth relay 36 has one end connected to the other end of the contact 34 and the third switching terminal 33d, and the other end connected to the second terminal 11b, and when the relay 36 is turned on, the welding power source is turned on to the torch 6. Electricity is applied.

37 is a normally open first contact for on-time of a fifth timer relay (to be described later), which has one end connected to the other end of contact 19, and 38 has a sixth contact whose both ends are connected to the other end of contact 37 and the second terminal 11b. A relay 39 is a limit switch for automatically starting forced welding after one welding cycle, one end of which is connected to the other end of the contact 19, and a seventh relay 40, which will be described later, is connected in parallel to the limit switch 39.
A normally open second contact of the relay, 41 is a seventh relay whose both ends are connected to the other end of the limit switch 39 and the second terminal 11b, and 42 is a trolley 4 whose both ends are connected to the other end of the contact 19 and the second terminal 11b. 43 is a welding indicator lamp, one end of which is connected to the contact 19 via the normally open contact 44 of the fifth relay 36, and the other end connected to the second terminal 11b.

45 is a secondary winding 45b in which both ends of the primary winding 45a are connected to the other end of the contact 19 and the second terminal 11b.
100V/ with one end connected to the other end of contact 19
A step-up transformer for 200V conversion, 46 is a normally open contact of the second relay 23 whose one end is connected to the other end of the contact 19, and 47 is a normally open contact of the second relay 23 whose both ends are connected to the other end of the contact 46 and the other end of the secondary winding 45b. 2nd timer relay, 4
8 is a third timer relay for setting the welding time of the first welding part W1, which is connected in parallel to the second timer relay 47, and serves to control the first welding timer together with a normally open contact of the third timer relay 48, which will be described later. Configure.

49 is a second terminal whose one end is connected to the other end of the contact point 19;
a normally closed third contact for the off time of the timer relay 47;
50 is a normally open contact for ON time limit of the third timer relay 48 whose one end is connected to the other end of contact 49, and 51 is a normally open contact for the OFF time limit of the 5th timer relay described later whose one end is connected to the other end of contact 50. The normally closed second contact 52 is the first and second non-welded portion N1, whose both ends are connected to the other end of the contact 51 and the other end of the secondary winding 45b.
This is a fourth timer relay for setting the non-welding time of N2, and is the first and second timer relay of the fourth timer relay 52 described above.
Together with the contacts 30 and 31 and a third contact, which will be described later, a welding pause timer is configured.

53 is a fourth terminal whose one end is connected to the other end of the contact point 19;
a normally open third contact for the on-time limit of the timer relay 52;
54 is a normally closed second contact of the third relay 26 whose one end is connected to the other end of the contact 53; 55 is a fifth timer relay for setting the welding time of the second welding portion W2; both ends are connected to the contact 54; Other end and secondary winding 45b
It is connected to the other end, and together with the first and second contacts 37 and 51 of the fifth timer relay 55 constitutes a second welding timer.

Next, the operation of the above embodiment will be explained.

Now, when the switch 33 is switched to the first switching terminal 33b on the "auto" side and the push switch 16 is turned on, the first relay 17 is energized via the power supply circuit of the switches 14, 15, and 16, and the first relay 17 is turned on. The contacts 18 and 19 are turned on, the closing circuit is self-held, power is started to be supplied to the control circuit and the drive circuit of the trolley 4, and as shown in FIG. While rolling on the upper edge part, the trolley 4 starts running backwards on the other thin plate 2b as shown by the arrow in the figure, and due to the rolling of the rollers 10a and 10b, the tip of the torch 6 is moved toward the one thin plate 2a side. The position of the welding part is traced, and the carriage 4 travels while the tip of the torch 6 is always held at a constant tracing position with respect to the welding part, and welding is performed.

At this time, while the truck 4 is running, both rollers 10a,
In order to prevent the thin plate 2a from coming off the edge of the thin plate 2a, the wheels 5 are tilted so that the trolley 4 rotates to the left, and the thin plate 2 is attached to both rollers 10a and 10b.
A pressing force is applied to the a side, that is, to the left.

Then, at the same time as the contact 19 is turned on, the first timer relay 21 is energized via the contact 22, and the contact 24 is turned on.
is turned on, the second relay 23 starts to be energized, and the second
The contact 46 of the relay 23 is turned on, the second and third timer relays 47 and 48 are energized, and the contacts 22, 25 and 49 are respectively turned off after a fairly long delay time t1 from the energization to the second timer relay 47. The contact 50 is turned on at a delay time t2 after the third timer relay 48 is energized.

At this time, switch 3 is turned on by turning on contact 19.
3. The fifth relay 36 is energized via the contact 35, the energization path to the welding torch 6 is closed, and welding of the first welding portion W1 is started.

Next, when the contact 50 is turned on, the fourth timer relay 5
2, the contact 31 is turned on at the same time as the fourth timer relay 52 is energized, the contact 30 is turned off at a delay time t3 from the energization to the fourth timer relay 52, and the contact 53 is turned on, and the contact 31 is turned on. During the time t3 from when the switch is turned on until the contact 30 is turned off, both contacts 30 and 31 are in the on state due to the on of the contact 31.
The fourth relay 32 is energized via the contact 35, the contact 35 is turned off, the fifth relay 36 is de-energized, and the torch 6 is de-energized.

Therefore, the time from the start of energization to the third timer relay 48 until the start of energization to the fourth timer relay 52 when the contact 50 is turned on, that is, the time from the start of energization to the third timer relay 48, that is,
If the time equal to the zero delay time t2 is set to be equal to the value obtained by dividing the length L1 of the first welding part W1 by the welding speed V determined from the leg length (=L1/V), the above-mentioned For time t2, the torch 6 is energized to weld the first welding part W1, and at the same time as the welding of the first welding part W1 is completed, the contact 31 is turned on by energizing the fourth timer relay 52, so that the first welding part W1 is welded. The fourth relay 32 is energized and the fifth relay 36 is energized.
energization is stopped, and contact 31 is turned on to contact 3
0 is turned off, the power supply to the torch 6 is stopped and welding is stopped, and this t3 time is the value obtained by dividing the length L2 of the first non-welded portion N1 by the welding speed V = ( L2/V), the power supply to the torch 6 is stopped for the above-mentioned time t3, the trolley 4 runs without welding the first non-welded part N1, and the next Second weld W
This will lead to a transition to the welding start point No. 2.

Furthermore, when the contact 53 is turned on, energization to the fifth timer relay 55 is started via the contacts 53 and 54 that are in the on state, and the contact 51 is turned off at a delay time t4 from the start of energization to the fifth timer relay 55. , the contact 37 is turned on, the contact 51 is turned off and the energization to the fourth timer relay 52 is stopped, the contact 37 is turned on and the sixth relay 38 is energized, the contact 28 is turned on, and the third When the relay 26 is energized, the contact 54 is turned off, the fifth timer relay 55 is de-energized, the contacts 37 and 51 are instantaneously turned off and on, respectively, and the fourth timer relay 52 is energized again when the contact 51 is turned on. is started.

At this time, during the period from the start of energization to the fifth timer relay 55 to the end of energization, that is, the time period corresponding to the delay time t4 of the contacts 37 and 51, the fourth timer relay 55
2 is in the energized state, and as described above, until the energization to the fourth timer relay 52 is stopped, the contact 30 is in the off state and the contact 31 is in the on state, so the fourth relay 32 is not energized during that time. The contact 35 is kept in the on state and the fifth relay 36 is energized, and the torch 6 is energized again to weld the second welding part W2. time t4, the second welding part W
The value obtained by dividing the length L3 of 2 by the welding speed V (=L3/
If it is set to be equal to V), the torch 6 will be energized for the above-mentioned time t4, and the second welding portion W2 will be welded.

Then, as described above, the fifth timer relay 55
After the power supply to the fourth timer relay 52 is restarted, the contact 31 is turned on instantaneously, and the contact 30 is turned off at the delay time t3, and the contact 31 is turned on at the delay time t3.
During the period from when the contact 30 is turned on until the contact 30 is turned off, that is, the time corresponding to the delay time t3 of the contact 30, the fourth relay 32 is energized via the contacts 30 and 31 that are in the on state, and the contact 35 is turned off and the fourth relay 32 is turned on. The energization to the relay 36 is stopped, the energization to the torch 6 is stopped, and welding is stopped, and the value (= L2/V), the power supply to the torch 6 is stopped for the above-mentioned time t3, the truck 4 runs without welding the second non-welded part N2, and then The welding cycle will now proceed to the welding start point of the first welding section W1.

By the way, when the trolley 4 moves to the welding start point of the first welding part W1 of the next welding cycle, the contact 2 of the second timer relay 47 described above
By setting the delay time t1 of these contacts 22, 25, 49 so that the contacts 2, 25, 49 turn off, the contacts 22, 25, 49 turn off at the end of one welding cycle, When the contact 22 is turned off, the energization to the first timer relay 21 is stopped and the contact 24 is turned off, and when the contact 49 is turned off, the energization to the fourth timer relay 52 is stopped and the contact 2 is turned off.
4, the energization to the second relay 23 is stopped and the contact 46 is turned off, and the energization to the second and third timer relays 47 and 48 is also stopped, and the control circuit in FIG. Returning to the state immediately after the start of the cycle, the second timer relay 47 is de-energized and the contact 22 is turned on, so that the first timer relay 21 is again energized and the first welded part W1 of the next welding cycle is turned on. Welding is started, and by repeating these operations, each weld on the one thin plate 2a side of the joint 3 is welded, and in the same way, each weld on the other thin plate 2b side of the joint 3 is welded. Welding of the parts is carried out. At this time, the time t1 required for one welding cycle is each time t2, t
3, t4, and t3, or slightly longer.

However, the limit switch 39 is mechanically turned on at the end of one welding cycle, and the fifth relay 36 is turned on by turning on the limit switch 39 and energizing the seventh relay 41.
It is assumed that current is forcibly applied to the welding section W1 so that welding of the first welding portion W1 in the next welding cycle is immediately performed.

Further, when all the welding on one thin plate 2a side of the joint 3 is completed, the limit switch 14 is mechanically turned off and the power supply to the control circuit is stopped, and the welding is completed and the traveling of the trolley 4 is stopped. I'm starting to do that.

Furthermore, when welding manually, switch 3
3 to the third switching terminal 33d.

The configuration of the control circuit is not limited to the one described above, and the present invention can be modified by adding a welding timer and a welding pause timer according to the length of the welding time of the welded part and the length of the non-welded time of the non-welded part. can be implemented.

〔Effect of the invention〕

As described above, according to the fillet welding method of the present invention, it is possible to automatically weld a plurality of intermittent welds of a lap fillet joint, and it is possible to improve work efficiency and to It is possible to improve the quality of the welded parts and maintain uniform quality of all welded parts, and the effect is extremely large.

[Brief explanation of drawings]

The drawings show one embodiment of the fillet welding method of the present invention, in which Figure 1 is a plan view, Figure 2 is a front view, and Figure 3 is a front view.
The figure is a plan view of the lap fillet joint, and FIG. 4 is a wiring diagram of the control circuit. 1...Base material, 2a, 2b...Thin plate, 3...Lap fillet joint, 4...Traveling trolley, 6...Welding torch, 10a, 10b...Roller, 48, 52, 5
5...Third, fourth, and fifth timer relays.

Claims (1)

[Scope of Claims] 1. A fillet welding method for automatically welding a plurality of intermittent welds of a lap fillet joint formed by stacking thin plates on a base material, comprising: traveling along a weld line of the joint; A welding torch is attached to a traveling truck, and a V that is provided on the truck and rolls on the upper edge portion of the welded portion of the thin plate.
The tip position of the torch is traced using a molded grooved roller, and the welding speed determined by the leg length, the welding time of each welded part and the non-welded part derived from the length of each welded part and the length of the non-welded part are determined. The non-welding time of the welding part is measured by a welding timer and a welding pause timer, respectively, and a welding power source energizes the torch for the time period measured by the welding timer, and stops energizing the torch for the period measured by the welding pause timer. A fillet welding method characterized by the following.