JPS59202186A - Attaching and detaching device for welding power source - Google Patents

Abstract

PURPOSE:To enable soft-touch connection of power receiving and feeding electrodes and sucessive mechanical locking by driving the toggle link mechanisms on the power feeding electrode side attached with conductive grasping members via elastic members for cushioning thereby attaching and detaching both electrodes. CONSTITUTION:A welding jig G is horizontally transferred by rails L from the outside of a multi-welding machine M and is set in the prescribed welding position in the machine M. The respective moving parts 22 of an attaching and detaching device 20 for a welding power source are also transferred in this stage and stop at the prescribed positions where respective power receiving electrodes 23 face the power feeding electrodes 24 in respective stationary parts 27. The toggle mechanisms 25 in the parts 27 are held open at the point of this time. When pressurizing air is then forced into an air cylinder 36, a piston rod 36a advances and the electrode chips 44, 44 at the top ends of arms 40, 40 begin to be closed to contact with the surfaces of the electrodes 24, 23. Since the impact thereof is absorbed by elastic members 43, 43 for cushioning, the connection is accomplished with the soft torch. Even if the pressurization to the cylinder 36 is interrupted while toggle links 41, 41 are fully extended, the mechanisms 25 are automatically locked at the closed state.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides electrical connection and disconnection between a fixed power supply device and a movable and replaceable welding jig.
This invention relates to a device for automatically attaching and detaching a welding power source.

Generally, in car body assembly processes, so-called multi-spot welding machines are used to efficiently assemble workpieces such as floors and body sides flowing through mass production lines.

This method has extremely high productivity because it can spot-weld predetermined parts of the workpiece at once using a welding jig that has a large number of welding guns set in advance according to the shape of the workpiece.However, when the shape of the workpiece changes, the welding jig is needs to be replaced.

During this replacement, productivity can be further improved if the electrical connection and disconnection between the power supply device and the welding gun, that is, the attachment and detachment of the secondary cable that supplies direct current to the welding gun, are automatically performed.

Conventionally, this type of welding power source attachment/detachment device includes, for example,
There is something like the one shown in Figure 2. This includes a cylinder mechanism 6 for making a power receiving electrode 4 protruding from a welding jig 3 detachably attached to a frame 2 having a power supply device 1 and a power supply electrode 5 of the power supply device + 11111 contacting and separating from each other.
It is suspended from the frame 2 via a universal joint 7.

As shown in FIG. 2, this cylinder mechanism 6 is constructed by passing two connecting rods 9 on both sides of front and rear end plates 8a, 8b of a U-shaped main body 8, and attaching a separate body to the connecting rods 9. A hydraulic cylinder 12 is inserted into the frame lO and the suppression plate 11 separated from the frame 10 so as to be able to move forward and backward, and is fixed to the rear end of the frame 10.
The rod 13 is electrically connected to the rear end plate 8b of the main body 8 and is engaged with the pressing plate 11. Then, by driving the hydraulic cylinder 2 with the hydraulic unit 14, the press plate ll and the frame 10 are slid, so that they face the press plate 11, which is a clamping member, and the front end plate lOa of the frame lO. The attached power supply electrodes 5, 5 come close to each other, and finally the receiver "Ij" located between them
”A connection is made between both electrodes by contacting pole 4.
A is an insulator sandwiched between the four electrodes.

However, in such a conventional welding power source attachment/detachment device, the sliding direction of the clamping member is installed in the thrust direction of the hydraulic cylinder serving as its drive source, so there is a possibility that the pressure source should be released while the electrode is energized. If this happens, the electrode pressure contact force may be insufficient, creating a gap in the contact area, which may lead to problems such as exposure to heat.

Furthermore, each of the power supply and power reception terminals, which are made of relatively soft copper plates, are forced to be directly and forcefully connected to each other, so there is a problem that they are easily damaged if opened and closed repeatedly over a long period of time.

This invention was made by paying attention to the various problems of the conventional technology, and it is possible to connect the power supply electrode and the power receiving electrode with soft touch, and by adding one or two of the -a electrodes. It is an object of the present invention to solve the above-mentioned problems by providing a welding power source attachment/detachment device that can mechanically lock the connection even if the drive source is released.

In order to achieve the above object, the present invention has a power receiving electrode connected to a welding jig which can be replaced depending on the workpiece, and a power supply fixed to a frame supporting the welding jig. A welding power source attachment/detachment device in which a power feeding electrode connected to the device is held in a holding position by a holding member, wherein the holding member is attached to the power feeding electrode side via a buffering elastic member. This welding power source attachment/detachment device is provided with a link mechanism and configured to conduct and release the conduction between the two electrodes, which are separated and facing each other, by driving the toggle link mechanism.

The present invention will now be explained based on the drawings. FIGS. 3 to 8 are diagrams showing one embodiment of the present invention.

To explain the configuration without switching, it is shown in Figs. 3 and 4 that
Reference numeral I is a multi-welding machine, which incorporates a welding jig G consisting of a large number of welding guns arranged in accordance with predetermined welding points of a work W (for example, a main floor of a car body) transported by a shuttle S. This welding jig G can be moved in and out of the main body of the welding machine M by means of a rail L having guide rollers R disposed thereon in order to be replaced according to the shape of the workpiece W flowing through the line. With a 20-piece welding power source attachment/detachment device,
The moving part 2 is attached to both ends of the transfer frame g of the disease-closing jig G through the plugs 21 and I-.
2, a power supply electrode 24 which faces the power receiving electrode 23 provided on the moving part 22 at the connection position, and a toggle link mechanism 25 for pinching and connecting both electrodes 23 and 24. It consists of a fixing part 27 attached to the outside 11111 of the frame m of M via a bracket 26.

(See Figures 4 and 5) The power supply electrode 24 of the fixed part 27 is connected to a power supply device 30 which is placed on the multi-welder M and includes a timer 28, a transformer 29, and a rectifier (not shown), and a secondary cable. (or bus bar) 31a, while the power receiving electrodes 23 of the moving part 22 are connected to the welding guns in the welding jig G through secondary cables (or bus bars) 31b, respectively.

6 and 7 are views explaining the welding power source attachment/detachment device 20 in detail. In the moving part 22, 32 is a conductor for attaching an electrode/secondary cable, and there is an insulating material 32a between the positive and negative pairs.
An elastic member 33, such as a spring, is mounted via an insulating material 32b, and is housed in a case 34 in a 70-ring state. At one end of this conductor 32, a pair of positive and negative electrodes 23, which are insulated from each other by sandwiching an insulating material 23a, are connected, and at the other end, a secondary cable 31b is connected to a welding gun.
It is attached using a connecting means such as bolts.

On the other hand, in the fixed part 21, it is a plate fixed to the tip of a bracket 26 attached to the frame m of a 35-piece multi-welding machine, and each of the two plates has a support 25a of the toggle link mechanism 25 and a support plate 25a of the toggle link mechanism 25, and Mechanism 25
For example, a bracket 37 to which an air cylinder 36 is attached as a driving source is identified by an appropriate means such as a bolt or a #4 contact. This plate 35. At the end of d5, an insulating material 24a is sandwiched in the same manner as the power receiving 1 electrode 23.
The power supply electrode 24, which is connected to the secondary cable 31a leading to the power supply device 30 by means of a pol) 7ffi, is held in place via a standoff member 38 and fixed using a coupling means such as a bolt.

Toggle link mechanism 25, an arm 40.40 which is rotatably connected to the pillars 25a, 25a with a fulcrum pin 39.39, and this arm 4.
a toggle link 41.41 pin-coupled to the 0.40 end, and a common coupling pin 42 of the toggle link 41.41 with
is secured to a piston rod 36a of an air cylinder 36 as a driving source, for example.

43. 43 is the arm 40 of the above toggle link mechanism 25
．． For example, a spring as a buffering elastic member which is bent opposite to the end portion of 40, a conductive clamping member (electrode chip) supported by this spring 43° 43 via an insulating material 45 at 44° 44, Figure 6 shows the piston rod 3
6a is advanced to sandwich the power feeding electrode 24 and the power receiving electrode 23 between the electrode tips 44 and 44, thereby creating a conductive state.

Next, the effect will be explained.

Welding jig G is horizontally transferred by rail L from a position outside multi-welding machine M, and is set at a predetermined welding position within the welding machine. At this time, each moving part 2 of the welding power source attachment/detachment device 20
2 are also transferred and stopped at a predetermined position 1k, and the terminals of each power receiving electrode 23 face the terminals of the power feeding electrode 24 of each corresponding fixed part 27 with the same polarity. At this point, the toggle link mechanism 25 of the fixing part 27 is in an open state as shown in FIG. That is, the toggle links 41, 41 are pulled and bent by the retracted piston rod 36a of the air cylinder 3b, and the arms 4iJ, 4
The tips of the electrodes 0 are expanded, and the electrode tips 44 and 44, which are quadruple clamping members, are separated from the power supply electrode 24. Next, when pressurized air is forced into the air cylinder 36 from an air source (not shown), the piston rod 3tia moves forward, and the toggle links 41, 41 of the Noda bend begin to groan.

This stretching force acts on the arms 40.40 and causes the arms 40, 40 to rotate in the direction of the arrow mark around the fulcrum pin 39.39, so that the ends of the arms 40.40 are facing each other and are in an expanded state. The electrode tips 44 , 44 begin to close and come into contact with the surfaces of the power supply electrode 24 and the power reception electrode 23 . The impact upon this contact is absorbed by the dead gold by the buffering elastic members 43.43 that support the both electrodes 23 and 44, so that the contact is very soft and the contact between the electrodes 23 and 23 is extremely soft.
, 24 or the electrode tips 44, 44. Moreover, when the Vislon rod 36a reaches near its forward limit, the expansion speed of the toggle links 41.41 becomes extremely slow, so that the compression of the buffer elastic members 43.43 is also performed slowly, so that the electrode tip 44. 44
The pressurization of both electrodes 23, 24 by the is non-impact. The boosting action of the toggle link mechanism 25 is required for this pressurization. The output of the air cylinder 36, which is the source of the drive 1, is sufficient to be low, and the size can be made smaller than the conventional one.

- Furthermore, when the toggle links 41, 41 are fully extended, even if the pressure to the air cylinder 36 is cut off or released, the closed door of the toggle link mechanism 25 is automatically locked. Therefore, there is no risk of causing problems such as electrolytic corrosion due to lack of air as in the conventional case.

Note that when the movable part 22 and the fixed part 27 are arranged to face each other, even if there is misalignment between the two parts, the movable part 22 supports the conductor 32 to which the power receiving electrode 23 is attached. The spring 33 has a floating function, and the fixed part 27 has a spring 43 that supports the tip 44.
also has a floating function, so misalignment is automatically adjusted during the process of connecting both electrodes.

In this way, an electrical connection is made between the welding gun and the city (one vehicle device), and the prescribed welding work proceeds.
When controlling the piston, conversely to the above, pressurized air may be sent to the return 11+11 of the air cylinder 36 of the drive source to move the piston rod backward. Extended toggle link 41
．． The lock by 41 is released, and then both supply and reception N poles 24
．． ) 3 is held between the electrode tips 44. Expand by 44 times. In this way, the welding jig G can be moved to the collision avoidance position in order to be replaced with another bath welding jig.

In addition, in the above 'JJi example, a case was explained in which the air cylinder 36 was used as the drive source for the toggle link mechanism 25, but there is no limit to this, and for example, a rotary actuator, a reversible motor, etc. It is also possible to consider a method in which the output shaft is screwed into a female threaded ring attached to the engaging portion of the toggle link.

Although not shown in the drawings, the structure can easily accommodate high usage rates of welding jigs by distributing cooling water to the conductor 32, power receiving electrode 23, power supply source 24, etc., which are paths through which large current flows. It is possible.

As explained above, according to the present invention, the long-shaped receiving mold 11-i attached to the moving part 1ltlJ in a horizontal state, and Since the structure is such that the power supply ring pole side (IV attached to the fixed part) is connected by holding it with a conductive clamping member via a toggle link mechanism provided in the fixed part, electrode pressure contact force is reduced during welding work. It is also possible to prevent problems caused by electrolytic corrosion caused by a lack of electrodes, and it is also possible to prevent damage to each other due to the sudden collision of a small clamping member with both the supply and reception electrodes.

In addition to the above effects, the power receiving electrode and the clamping member at the opening/closing end of the toggle link mechanism are supported in a floating state via an elastic member, so that the connection between the two electrodes becomes even more gradual and soft, and the positioning becomes easier. This method does not require much precision, and the secondary cable connecting the welding gun and the power receiving electrode can easily follow the movement of the welding gun.

[Brief explanation of drawings]

FIG. 1 is an overall 11111 side view of a conventional welding power source attachment/detachment device, FIG. 2 is a side view of the main part of FIG. 1, and FIG. 3 is a perspective view showing an attached butterfly according to an embodiment of the present invention. Figure 4 is a schematic view of the ■ arrow in Figure 3, Figure 5 is the main point of Figure 4 81j IUI
6 is an enlarged side view of the main parts of an embodiment of the present invention in which the mounting is not uniform, and FIG. 7 is an enlarged plan view of the main parts. 2 is also an explanatory diagram of the operation of the main part. 1.30... Power supply device 2, m... Frame 3, G... Welding jig 4.23... Receiver' thf electrode 5.24... Supply city electrode W... Work 10a, It
......Holding member 20......Welding power source attachment/detachment device 22.
......Moving part 25......Toggle link mechanism 27.
..... Fixed star part 3 I a , : i l b ..... Secondary goople (or bus bar) 32 ..... Conductor

Claims (1)

[Claims] The power receiving electrode is connected to a welding jig that is used as a contact point depending on the workpiece, and the power supply terminal #1 is fixed to the frame that supports the respective bath welding jig and connected to the power supply device. , a welding source attachment/detachment device d configured to be clamped by a clamping member at the connection position, and a toggle link mechanism in which a conductive clamping member is attached to the supply terminal side via a buffering elastic member. 24) A welding power source attachment/detachment device characterized in that by driving the toggle link mechanism, the two electrodes separated and facing each other are released.