JP3101765B2 - Bar end material automatic welding method - Google Patents

Description

[Detailed description of the invention] (Industrial application field) In the present invention, when a standard bar having a predetermined length is machined on an NC lathe or the like, the machine cannot be lathed by about 300 mm due to the mechanism and becomes scrap. The present invention relates to a welding method for welding a rod end material, which has been used, to form a connecting rod material having a predetermined length.

(Prior art) Conventionally, in order to weld these bar ends, there is no special welding machine just because it is a peculiar end material, but it is usually welded with a general welding machine. Is easy to occur,
In addition, the welded portion is liable to build up, and these harmful effects occur when turning the welded connection rod again into a lathe, causing large runout and inaccurate finished products. It was difficult and had to be scrapped.

(Problems to be Solved by the Invention) The present invention is intended to reduce the distortion generated in the butt-welded portion at the time of welding for successively welding and connecting rod ends produced during lathe processing and reusing them as a rod for lathing. An object of the present invention is to minimize lamination, enable connection without building up, and increase the accuracy of a lathe product in the reuse of bar ends.

(Means for Solving the Problems) In order to achieve the above object, the present invention supports the chucks, which are opened opposite to each other on a coaxial center, synchronously and rotationally to rotate the chucks, and welds the rod ends to be welded to each other. In order to grasp the end of the welding with the chuck in abutting manner, a welding device having a cooling function is installed on a side portion between the two chucks, and the welding device of the welding device is adjusted according to changes in high and low speed rotation of both shafts. Using a welding machine that changes the welding current value and cools the welded part with the cooling function, chamfers each joint part of the rod end material, grips it with each chuck, butts it, up to one rotation Is welded at a low speed of about 12 rpm and low heat, then welded at a high speed of about 40 rpm for a fixed time, then welded at a high speed at a fixed rate, and welded at a low heat lower than the low heat of one rotation, then at a fixed time Inject cooling air with the cooling function of welding equipment at high speed rotation It proposes a rod end member automated welding method for welding a constant manner.

(Effect) By gripping each piece of material coaxially with the opposing chuck and abutting the chamfered part straight without distortion, the buildup at the joint part is prevented, and the initial state is maintained while maintaining this state. The low temperature welding at the low speed rotation gradually adjusts the butting part to the welding temperature, then the high speed welding at the high temperature produces a reliable welding, and the high temperature welding is performed at a high speed to perform the low heat welding.
The temperature of the weld decreases as the weld gradually adapts to the cooling temperature difference, and the cooling air is injected at the final high-speed rotation to allow the weld to cool without a sudden change in temperature. A joining bar material free from cracks can be obtained.

(Example) Next, a description will be given of a rod end material automatic welding method according to the present invention. In the drawings, FIGS. 1 to 4 show a rod end material automatic welding machine used for carrying out the present invention method. Reference numeral 1 denotes an automatic welding machine comprising a shaft 3, a collet chuck 9, a drive motor 18, and a welding device 20.
On the coaxial center, a long bar 21 welded along the length direction is sequentially attached to the left and right sides of the shaft 18 so as to be axially supported to rotate synchronously via a motor 18 having a speed control function on the coaxial center. A shaft 3 having a guide hole 4 to be introduced is rotatably inserted into a support sleeve 6 via bushes 6b, 6b, and a fastening handle 5 is attached to a rear end 3b.
The support sleeve 6 is supported by pillow bearings 8 and 8 so as to face the front flange 6a.

The collet chuck 9 is provided with a tightening adjustment member 12 and a collet, which are screwed to a flange base 11 having a sleeve portion 11a and a flange edge portion 11b so that a female screw ring 13 and a male screw ring 14 can advance and retreat along an axis.
A push ring 15 provided with a taper portion 15a opposite to the taper portion 10a of 10 is coaxially assembled via thrust bearings 16 and 16, and the sleeve of the flange base 11 is passed through the shaft portion 10b of the collet 10 through this. It is inserted through the portion 11a and tightly joined together with a nut 17 (see FIGS. 3 and 4). Tightening adjustment member 1
The female screw ring 13 of FIG. 2 is provided with a tightening handle 13a, and the male screw ring 14 is provided with a non-rotating handle 14a.
By rotating the female screw ring 13 in 3a, the pressing action of the pressing ring 15 on the collet 10 is adjusted to open and close the gripping portion of the collet 10. The collet chuck 9 engages a nut 17 with the tip of the shaft 3 with a pin 17a.
The collar edge 11b is connected to advance and retreat the screwing of the nut 17 to the collet 10 even when the shaft 3 rotates, and by rotating the shaft 3, the nut 17
Can be removed to remove the collet 10, which is convenient for replacing the collet 10 depending on the gripping size.

As described in an embodiment of a welding method using the present welding machine to be described later, the welding device 20 has a cooling function for cooling and removing the remaining heat of the welded rod ends with cooling air that has been jetted out after welding, An argon welding torch capable of changing the welding current value is installed on a base between the collet chucks 9, 9 facing left and right so as to face from the side, and attached to the support sleeve 6 of one shaft 3. Pulley 7
The motor 18 with speed control function of the pulley 18a
The other synchronous pulley 7a on the support sleeve 6 is belt-linked to the synchronous pulley 7a on the support sleeve 6 of the other shaft 3 via the pulley 19a of the slave shaft 19 so that the two shafts 3 , 3 are rotated synchronously, the welding current value of the welding device is changed according to the change of high and low speed rotation of both shafts, and the heat quantity of welding to the rod end material is changed,
Connections are made so that the parts to be welded can be selectively set to cool the parts to be welded by the cooling function of the welding device.

The welding process of the automatic rod end material welding method according to the present invention will be described using the above-mentioned automatic rod end material welding machine. As shown in the timing chart of FIG. After the chuck is held by the chuck, start, welding starts when the switch is turned on, the current value at this time is normal 40 A T1 (setting 1 second), the rotation of the motor starts (the rotation speed at this time is welding speed 8 mm At the setting of / sec, the number of revolutions differs depending on the outer diameter of the end material and can be selected with a switch.) Welding at 40mm at 8mm / sec between T2 (during one round of the end material) After T2, between T3 at 40rpm 60A setting (5sec) Welding After T3, welding at T4 at 40 rpm 20A (4 seconds) After T4, T5 (5 seconds) cooling at 40 rpm 0A, air ON-First, weld the offcuts once. In this state, distortion occurs due to the difference in the speed of natural cooling between the start point and the end point, and the entire assembly is rotated while welding so that it has the same temperature. This makes it possible to take out a straight center, and to uniformly cool with cooling air injected by the cooling function provided in the welding device while rotating at high speed, so there is no shrinkage due to temperature difference and no build-up No bonding is obtained.

(Effects of the Invention) As described above, according to the present invention, the distortion generated in the joining portion in the initial welding process is such that the joining portion quickly becomes uniform by heating and welding at high and low stepwise temperatures by rapid rotation. By cooling the joint with a cooling device in a state of rapid rotation after welding and heating, uniform cooling avoiding sudden temperature changes can be obtained, and by lathe processing that has become unusable until now It has become easy to weld the generated incomplete rod end material to a long joining rod material having no distortion (runout) that can withstand the accuracy of lathing again.

As a result, distortion occurs in the joining and welding, so that the rod end material, all of which has been discarded as scrap, can be effectively used, which is economically beneficial, and is a long joining rod material without distortion (run-out). Can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of an automatic rod end material welding machine used for carrying out the automatic rod end material welding method of the present invention, FIG. 2 is a side view of the same, and FIG. FIG. 4 is an exploded perspective view of the chuck part, and FIG. 5 is a timing chart of a welding process by the rod end material automatic welding method according to the present invention.

────────────────────────────────────────────────── (5) References JP-A-59-16681 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B23K 9/00, 37/00, 37 / 04

Claims (1)

(57) [Claims] The chucks to be opened opposite to each other on a coaxial center are axially supported so as to be synchronously driven to rotate, and the rod ends to be welded should be gripped by the chucks with their ends abutting each other. Comb, a welding device with a cooling function is installed on the side between the two chucks, and the welding current value of the welding device is changed according to the change of high and low speed rotation of both shafts, and the welded part is cooled by the cooling function. Using a welding machine to be cooled, chamfering is applied to each joint of the bar ends, gripped by each chuck, and butted.
Weld at a low speed of about 12 rpm and low heat until one rotation,
Thereafter, high-temperature welding is performed at a high speed of approximately 40 rpm for a fixed time, and then welding is performed at a high speed at a constant speed and low heat lower than the low heat of one rotation. Automatic welding method of rod end material that is set and welded as required.