JPS58159985A - Spot welding device for multispotted work - Google Patents

Abstract

PURPOSE:To suppress the reckless movement of the work and to improve the working efficiency for spot welding of the multispotted work by supporting two units of welding units to frames and providing means of moving the units separately in respective positions. CONSTITUTION:A guide rail 11 is fixed to columnar frames F3 on both sides and right and left traversing frames 11L, 11R are supported thereon, and are slided separately by traversing shifters 16L, 16R. Vertical guide rods 21 are provided to both traversing frames 10L, 10R, and unit supporting frames 20L, 20R are supported vertically movably thereon. Frames 4L, 4R are mounted to the front stage of advancing and retreating rods 30L, 30R, and welding units UL, UR are supported thereto. Advancing and retreating cylinders 32L, 32R are supported on the frame 31 on the rear side, and are penetrated through unit supporting frames 20L, 20R. The unit frames 4L, 4R support the head frames that carry welding heads 6L, 6R, vertically movably. The work W is supported by a supporting base 70 in parallel with a vertical frame F3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a spot welding device for a multi-point workpiece, which is suitable for performing a large number of spot welds on a long planar workpiece.

When spot welding (hereinafter sometimes abbreviated as "lighting") a large number of three spot welding points (hereinafter referred to as "dot points") using a conventional spot welding machine, we usually start welding at one end of the workpiece and weld the dots one after another. Continue dotting to the other end. However, when a multi-dot workpiece is long in one direction, when one end of the workpiece begins to be dotted, the other end of the workpiece becomes cloudy, which is an inconvenience that seriously impedes normal welding of the workpiece. occurs.

The apparatus of the present invention supports two welding units by the machine frame, and welds the two welding units in the lateral direction ( It is characterized by being configured so that it can be moved separately in the longitudinal direction of the workpiece), the up-down direction, and the front-rear direction (directions perpendicular to the length of the workpiece).

The multi-dot work that the device of the present invention targets is t44 diagram W
It has a planar shape that is long in one direction, and has a large number of dots indicated by X marks. The dots of such a multi-dot work are Ll from both ends.

They are arranged in many rows like L, . . . and R1, R4 .
...Often includes multiple points of impact, such as a fist. If we count this row of dots sequentially from both ends, we can count them toward the center of the workpiece.
Left dot row group of n columns of Ll, L, ......Ln from the left and the same number of R1, R, ......Rn from the right or R1
It is divided into a right side dot row group with one more row up to 1+1.

According to the apparatus of the present invention, all dot rows of a multi-dot workpiece are divided into the above two groups, and left and right welding units are One welding head 6L, 6R for each (
(described in detail later), you can start dotting at the same time. The order of lighting is arbitrary, but when dotting starts from Ll& and Rlm, it is normal to do it as shown by arrow S in Fig. 14.

In this first step, the two welding heads move symmetrically toward the center of the workpiece.

After performing an arbitrary number of dots in the previous step, for example, when the LEM dots and RIIL dots are finished, one of the two welding heads, for example, the right welding RAD 6R, will be placed in that dot row. The next welding point R3a IIC of the group is moved, but the other left welding head 6L moves to Ln of the stage corresponding to the R1m dot point in the center dot row of the left welding dot row group belonging to this.
Move to point a.

Here, after dotting both Lna @ I4a dots at the same time, the remaining dots are dotted (later step) while moving the two welding heads in the same direction as indicated by the broken line arrows, for example. When welding a workpiece with an odd number of dot rows, there may be cases where one dot row is worked alone at the end on the welding head side on one side (in this example, if the center of the right dot row group is the Rn + 1 row, then the right). This situation is much more advantageous than one in which two welding heads interfere with each other in the center of the workpiece, making one inoperable.

Next, Akira Ipponba's welding device will be explained in detail based on the drawings.

In Figures 1 to 3, the melt [17] supporting the entire device is shown.
The frame F has, at the rear of the base 7 frame Fl, a vertical frame F in which the left and right columnar frames Fl * Fl are connected by a connecting frame F4. ◇ In the example, the columnar frames F's and ゛F's on both sides
Upper and lower horizontal guide rails 11, 11 are fixed to the left horizontal motion frame 10L and right horizontal motion frame 10R,
If 15 (K is a support platen) 14 on the outside of the columnar frame Fs on both sides which is slidably supported by the sliding arms 12;
．． 14 is provided, and a horizontal side support frame 15, 15K is attached to the left lateral movement shifter 16L.
and right lateral movement shifter 16B are supported, and the operating rods 17 of both lateral movement shifters move left and right lateral movement 7L/-m 10L, 10R.
connected to each side plate.

Due to the expansion and contraction of Mobile Chic, the left and right horizontal movement frame 10L,
The IOR has separate horizontal movement frames, and the 10L and IOH have left and right frames (
1) An x-knit vertical movement device 2 is installed.

Each lateral movement frame has a pair of vertical guide rods 21, 2.
1, and supports the left unit support frame 20L and the right unit support frame 20R, respectively, so as to be movable up and down. Both unit support frames are moved up and down by rotating the handle 22. This device serves as a rapid feed mechanism for the welding tool knit. , the right unit advances and retreats! It is supported by left and right unit frames 4L and 4R attached to the front ends of each OR.

In the embodiment, horizontal rear support frames 51 and 61 are fixed to the rear of the left and right unit support frames 20L and 20R, respectively, and left advance/retreat cylinders 52 are attached to these, respectively.
L and right forward/backward cylinder 32R are supported. The left unit advances and retreats! OL is the left unit support frame? 'OL and left advance/retreat cylinder 321. It extends back and forth through the cylinder, and moves back and forth together with the piston (not shown) of the cylinder. Similarly, the right unit advancement/retraction rod 60R also moves back and forth through the right unit support frame 20B and the right advancement/retraction cylinder 32R. Both units advance and retreat! OL and 50R are prevented from rotating around their axes by known means.

The left and right unit frames 4L and 4R have, for example, vertical guide seals 41 on both front sides thereof,
Left and right head frames 5L and SR carrying left and right welding heads 6L and 6R are vertically movably supported. A head elevating cylinder 40 is supported above the unit frame by a cylinder support plate 42, and raises and lowers the head frames SL and 5R.

The head frames 5L and 5R each have an elevating frame portion 51 that is connected to the head elevating cylinder 40K and moves up and down;
A balloon-shaped frame 52 that is recessed toward the rear in an almost balloon-shaped manner.
The lower electrodes 61 of the left and right welding heads are fixed to the lower front end of the balloon-shaped frame 52. The upper electrode 62 is supported by the lifting frame part 51K so as to be able to rise and fall freely, and is moved up and down by the electrode cylinder 60. The functions of the head elevating cylinder 40 and the electrode cylinder 60 will be explained later.

A workpiece support stand 70 is arranged in front of the welding head, and the horizontally long multi-dot workpiece W is mounted on a vertical frame F.
, supported parallel to .

The illustrated workpiece support stand 70 is in the form of a pair of L-shaped support stands on both sides, and is fixed on a horizontal pedestal 76 of a workpiece support device, generally designated by reference numeral 7, and is a known clamping device (not shown). to support both ends of the workpiece W.

The workpiece support device 7 is entirely supported on a frame F7 fixed to the front of the base frame. On both sides of the stationary frame F7, there are shaft support frames F,, F, supporting a swing shaft 71, and the swing shaft 71 connects the movable plates 72, 72 on both sides with the pedestal 76. A swing frame is swingably supported.

The swinging plate 7z is pivoted near its upper end by a swinging shaft, and an operating rod 75 of a work shifter 74 such as a hydraulic cylinder is connected to a pedestal 73 connecting the lower end of the swinging plate 7z. The swing frame is swung around the shaft 71. This configuration is useful for tilting the workpiece so that the striking surface becomes horizontal when the workpiece W has an arcuate shape or a bent portion as shown in FIG. F. is a thick support frame that supports the base end of the shifter, and 76 is a shifter receiving frame. In the illustrated embodiment, there is one work shifter 74, but two work shifters can be arranged on both sides of the pedestal 76 if necessary.

Next, the proximity sensing device 8 will be explained. Mainly referring to FIG.
1 is placed in a predetermined position and fixed thereon. On the other hand, the left and right unit advancement/retraction levers AOL, 50
The rear ends of B are extensions 6 that reach above the mold plate 80, respectively.
6, each having a left and right proximity switch 82L,
I support 82R. Each proximity switch has the extension portion 6
Lifting member 8 is attached to switch support 86 attached to the rear end of 6.
4, the vertical position is adjustable, and both proximity switches,
The sensitive parts at the tips (lower ends) of each of the pins 82L and 82R are close to the upper surface of the magnet pin 81 (with a gap of 2 mm).
horizontal movement y ray A
Lateral movement of IOL, IOR and unit) advancement and retreat! OL
, 50H moves separately on the mold plate 8o. The magnet pins 81 are arranged corresponding to the positions of a large number of dots on the workpiece W.

When the multi-striking workpiece W is supported by the workpiece support device 7 that is displaced according to the inclination of the dot-striking surface, the Macnet pin is arranged at a corresponding position corrected by calculation in advance.

Here, the use of the spot welding machine of the present invention having the above configuration will be explained.

The lower electrode 61 and the upper electrode 62 of the welding head 6 (common to L and R) have the illustrated spacing d along the vertical axis 1 [K, normal '; This interval is made to be larger than t (including the case where the workpiece W is thick and has an arcuate or inclined portion wl, etc., and is tilted as shown by the chain line in FIG. 3). If the opening between both electrodes (portion d) and the workpiece support surface are not aligned, turn the rapid-forwarding handle 22 of the unit vertical movement device 2 as shown in FIG.

Align the positions as shown in Figure 3, and move the work horizontally so that it can move forward and backward between both electrodes. It changes depending on the joint! The gap between the Dunnett bin 81 and the proximity switch 82 is corrected and adjusted manually or automatically by the elevating member 84. The electrodes of both welding heads 6L and 6H are arranged to face the dot rows LH and R1 at both ends of the workpiece.

The spot welding device of the present invention can be automatically operated under the control of a sequence controller (not shown) in combination with a proximity sensing device 8 according to a predetermined program. For example, the mode is as follows.

When the start switch is turned on, the forward and backward movement cylinders 52L and 52B of the unit forward and backward movement device are actuated, causing both welding heads to advance toward the dot rows Ll and R1K at both ends of the workpiece. As the unit advances and retreats, the proximity switch 8
2 is advanced, the L1 dot row and R1 on the mold board 80
Macnet pins 81 are arranged corresponding to each stage of the dot rows a to . Proximity switch 82L on both sides,
When 82R reaches directly above each magnet pin,
The forward and backward cylinders to which they belong are stopped, and then the welding units UL and UR are started.

The welding unit) U (common to UL and UR) of the embodiment operates as follows when started.

Upon startup, first the piston of the head elevating cylinder 40 (
(not shown) rises to bring the lower electrode 61 into contact with the lower surface of the workpiece. An air cylinder is used as the head lift cylinder 40, and its operating pressure is controlled by the head frame 5 (
5L, 5H common) and welding head 6 (6L, 6H common)
The overall weight is set to be greater than G. It goes without saying that when the head lifting cylinder 40 operates, the work shifter 74 of the work supporting device 7 operates to horizontally support the first hitting surface W1.

Next, the piston (not shown) of the electrode cylinder 60 descends to press the upper electrode 62 against the upper surface of the workpiece.

Electrode cylinder 60 is typically a hydraulic cylinder. The electrode pressure P must be selected in a certain relationship with the welding current, and varies depending on the material of the workpiece, plate thickness, contact area between the electrode tip and the workpiece, etc., so the pressure generated in the electrode cylinder 60 is adjusted. By doing so, it is possible to perform welding while applying the optimum pressing force P to the workpiece.

When one dotting point is completed, the electrode cylinder 60 and the head lifting/lowering cylinder 40 return to their original states and release the workpiece.

According to the welding unit that operates as described above, the workpiece is pressed between the lower electrode 61 and the upper electrode 62K, and current is applied while maintaining the optimal electrode pressure P, so that extremely uniform spot welding can be performed. It can be effective. Furthermore, if the workpiece supporting device operates so that the dot surface of the workpiece is always horizontal and provided to both electrodes, the welding result will be good and there will be an effect of eliminating wear due to uneven wear of the electrodes.

According to the welding unit that operates as described above, the contact pressure (welding pressure) between the two electrodes that pinch the workpiece is always maintained at a constant pressure of α+β &CJIl, so that extremely uniform spot welding can be performed. In addition, if the workpiece support device operates so that the workpiece surface is always horizontal and provided to both electrodes, the welding result will be good and there will be no wear due to one-sided wear of the electrodes. However, the device of the present invention is not required to have such a specific configuration.

After the work is released, the cylinders 52L and 52B move forward and backward again.
(In the case of lateral movement, lateral movement shifters 16L and 16R) are operated to move the left and right welding units to the next programmed dot point, and the operation of dotting in the same order is repeated.

When both ends of the programmed scheduled number of lights have been lit, only one welding unit moves to the center dot row of the dot row group to which it belongs, for example, the Ln row, and from then on both welding units face in the same direction. According to the welding apparatus of the present invention described above, spot welding of a multi-dot workpiece can be performed by two dots each by the operation of IIm. The number of operations is 1/1 for dotting! As a result, it is possible to completely suppress the workpiece undulation phenomenon, which has the effect of significantly improving work efficiency.Moreover, the efficiency is reduced due to interference between the two devices resulting from the use of two welding heads. Careful avoidance of decline has the effect of gaining benefits.

[Brief explanation of the drawing]

The drawings show an example of the spot welding device and leakage of the present invention, and FIG. 1 is a front view of the spot welding device, and FIG.
The figure shows a plan view with a part of the connecting frame cut away.
Figure 3 is a cross-sectional side view of the rear support frame with part of the columnar frame and side plate in front of the lateral motion frame removed, and Figure 4 is a plan view showing an example of a multi-dot workpiece. be. F...Welding machine frame W...Multi-dot work UL
(tTR)...Left (right) lIII-L et 1
...Unit lateral movement device 2...Unit vertical movement device 6...Front bale movement device 6L (6B)...
Left (right) # Contact head agent Tsuneteru Aragaki

Claims (1)

[Claims] 1. Left and right columnar frames F, , F provided at both rear sides of the base frame Fl of the spot welding machine. vertical frame F1 including vertical frame F1, horizontal horizontal guide rails 11, 11 supported by vertical frame F, horizontal guide rail 11
, 11, the left lateral movement frame 10L and the right lateral movement 7 frame 10R1, the left lateral movement frame FsK, which is supported by the left lateral movement frame 10L and which moves the left lateral movement frame 10L from side to side. A right lateral movement chic 16R1 that is supported by the frame F and moves the right lateral movement frame 10R to the left and right; a left and right lateral movement frame 10L;
01 K A left side support frame 20L and a right unit support frame 20R1 are supported so as to be able to move up and down, respectively.A left forward/backward cylinder 52L and a right forward/backward cylinder 62R1 are supported at the rear of the left and right unit support frames 20L and 20g, respectively.
A left unit advancement/retraction lever 50L, a right unit advancement/retraction lever 60R1, a left and right unit advancement/retraction lever 30L, which move back and forth by the left and right advancement/retraction cylinders 52L and 52R, respectively.
! Left welding unit UL and right welding head) UR supported by left and right unit frames 4L and 4R, and left and right welding heads 6L, respectively, supported by the front layer of OR. , 6H A spot welding apparatus for a multi-point workpiece, comprising a workpiece support stand 70 that supports the workpiece over the front surface of the workpiece. 2. The left and right welding units UL and UR, respectively,
Left and right unit frames 4L and 4R, and left and right head frames SL and 5R that are supported by the left and right unit frames 4L and 4R so as to be able to rise and fall, respectively. Left and right welding heads 6 are provided with a lower electrode 61 fixed at the front end of the U-shaped frame of each of the left and right head frames 5L and 5R, and an upper electrode 62 that is movable up and down opposite to this.
L, 6R, left and right head frames 5L, SR, respectively connected to the left and right head frames 5L, 5R and welding heads 6L, 6B is connected to the head frames 5L, 5R and the welding heads 6L, 6B is a greater force than the sum of the weights G. The left and right 9 head lifts and lowers expand and contract with operating pressure. Left and right electrode cylinders 6 are connected to the cylinder 40 and the upper electrode 62 and can apply a predetermined electrode pressure P to the workpiece.
0. A spot welding device for multi-dot workpieces according to claim 1, wherein the spot welding device is configured by: 3. The work support stand 70 is connected to the left and right shaft support frames Fs
, F@tlc supported swing shafts 71.71
It is mounted on a pedestal 76 of a swinging frame that can swing around the axis, and is connected to an operating rod 75 of a work shifter 74 that operates based on the swinging frame (welding machine frame). The spot welding device for multi-point workpieces as described in item 1. 4. The left and right unit advancing/retracting rods MOL and !OR each have an extension portion 66 at the rear thereof, and the extension portion 36 is arranged on the template of the proximity sensing device 8. The left and right proximity switches 82L cooperate with the magnet pin 81.The left and right lateral movement switches 82L each carry 82R, and the left and right lateral movement switches 16L,
16R, left and right advancing/retracting cylinders 62L, 52R, and left and right welding units) UL, UR are sequentially controlled by a sequence control device combined with a proximity sensing device 6.The spot of the multi-dot work according to claim 1 Welding equipment.