JPS63268576A - Device for supporting resistance welding machine - Google Patents

Abstract

PURPOSE:To prevent a cable for supplying electric power and hoses for supplying and discharging cooling water and compressed air from being damaged by coupling a cradle with a welding machine mounting part and connecting paths of the electric power, the cooling water and the compressed air for driving electrodes to the welding machine side, respectively. CONSTITUTION:Conductors of the cable for supplying the welding electric power are connected to a connection part 69a separately for positive and negative electricity and the hoses for supplying and discharging the cooling water are connected to cooling water hose connection parts 75 and 76. Moreover, the hoses for supplying and discharging the compressed air are connected to compression air hose connection parts and a group of wires are connected with wires corresponding to a motor 56 and an encoder respectively. When electrode chips 13 and 14 are positioned at the welding positions, in case it is necessary to change the directions of yorks 11 and 12, a main shaft body structure 2 is rotated by a necessary angle by the rotation of the motor 56. The angle of rotation is controlled by a signal from the encoder. The cable for supplying the welding electric power, the hose for supplying the cooling water and the hoses for supplying and discharging the compressed air do not rotate longitudinally by the existence of a rotation connection part 5 for the electric power and a rotation connection part 6 for a fluid path with respect to the rotation of the main shaft body structure 2.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention provides a resistance welding machine, for example, a spot welding machine, in which a cradle that supports the gun is supported so as to rotate around the l-axis, and the welding gun side is This invention relates to a support device for a resistance welding machine that can appropriately supply electric power, cooling water, and compressed air to the machine.

<Prior Art> The gun of a conventional spot welding machine is attached to the final shaft end of the arm of a robot or special machine via a cradle. The gun supported by the cradle is moved to the welding position by the movement of the arm and performs the welding operation. Flexible laminated copper plates, kickless cables, and hoses are used to supply electricity, cooling water, and compressed air for driving the electrodes to the gun. The proximal end is connected to a fixedly provided supply section with an appropriate slack. This slack part is designed to allow the welding machine to rotate and move, and in some cases it is supported by a hanging fixture from the ceiling of the factory.

<Problems to be Solved by the Invention> In the conventional spot welding machine, the cable for power supply and the hose for fluid supply must have sufficient margin when the welding machine rotates. The slack part becomes considerably large. The fact that this slack portion is large is that it is often difficult to suspend and support it when installing these devices, and it can get in the way of other equipment, easily damage itself, and furthermore, such damage may prevent the welding machine from operating. There is a problem that will disappear. In addition, with the conventional configuration, it is almost impossible to expect the welding machine to be able to rotate more than one rotation per rotation of the l axis.
Therefore, in order to weld at a large number of welding points along the circumference, it is necessary to rotate the welding machine in the opposite direction and unthread the cables and hoses, resulting in problems such as 1) poor work efficiency;

Means for Solving the Problems> The means of the present invention has a welding machine mounting section at one end, and a power supply path and a cooling water channel that extend along the longitudinal direction so as to reach the mounting section. and a main shaft structure provided with a compressed air passage, a main body rotatably supporting the main shaft structure, a rotary drive section provided in the main body to rotationally drive the main shaft structure, and the power supply to the main shaft structure. a power rotary connection portion having a conductive circumferential surface portion connected to the curved surface portion, a contactor supported on the main body side so as to be in contact with the curved surface portion, and connected to the power supply conductor; It consists of a fluid passage rotary connection part provided with a hose connection part on the main body side so as to connect to each compressed air passage separately.

According to this method, the main body is attached to the tip of the arm of a robot or a special machine, and the cradle of a spot welder, for example, is connected to the welding machine attachment part, and at the same time, the power and cooling required by the welding machine are Connect the water and electrode drive compressed air passages to the welding machine, connect the tip of the power supply conductor to the contact, and connect the cooling water and compressed air passages to the hose connections. Use by connecting a hose connected to a supply source. The power supply cable, the cooling water supply/discharge hose, the compressed air supply/discharge hose, etc. are bundled together and partially fixed, for example, along the arm, with enough room for movement of the arm. The welding machine attached to the main shaft structure is rotatable with respect to the main body because the main shaft structure is rotated by the rotary drive unit. With respect to the rotation of the l-axis of this welding machine, the electric power supply conductor, the cooling water supply/discharge hose, and the compressed air supply/discharge hose are connected to the main body, so they do not rotate as a result of the rotation.

Embodiment One embodiment of the present invention will be described with reference to the drawings. In the figure, 1 is a spot welding machine, 2 is a main shaft structure, 3 is a main body, 4 is a rotation drive section, 5 is a rotation connection section for electric power, and 6 is a rotation connection section for a fluid passage.

The spot welding machine 1 has a cradel 10 and a yoke 11.1.
2. Electrode chip 13.14, electrode driving air cylinder 1
It is composed of 5th grade. The cradle 10 has a base end attached to the tip member 20 of the spindle structure 2, which will be described later, via an insulating plate 16 and a yoke 6, and has yokes 11 and 12 at the tip, as shown in FIGS. 1 and 2. Electrode tip 13.14 through
Installed and air cylinder 15 joke 11.1
2, the electrode tips 13 and 14 are moved forward and backward relative to each other. The electrode tips 13.14 are energized via the cradles 10.10 on both sides.

The main shaft structure 2 is constructed by sequentially joining a tip member 2o, a cylindrical portion 21, an insulating member 38, 22, a conductive member 23, an insulating plate 24, a conductive member 25, and an insulating member 26 from the side of the welding machine 1. Conductive pipes 27a, 27 that form an integral shaft and constitute part of the power supply path and part of the cooling water path therein.
b and an insulating pipe 28 forming part of the compressed air passage.
a, 281) are provided along the longitudinal direction. The tip member 20 is connected to the cylindrical part 21 with seven flange, and the peripheral outer surface 29 is used as a cradle mounting surface, and the cradle 10 and 10 are insulated to this mounting surface so as to be electrically insulated. It is installed with pol) 30.

Conductive pipes 27a and 27b pass through the tip member 20, and an insulating pipe 28a128b terminates inside the tip member 2o. Tip member 20 of conductive pipes 27a, 27b
The portions passing through the interior are insulated by insulating tubes 31, and the tip member 2
The ends protruding from 0 are screwed to members 32a and s2b so as to be electrically connected to the cradles 10 on both sides respectively. The members 32a and 32b have an abbreviated front shape, and are spaced apart from each other with a crepe /l/1 on each side.
0 with Porto 33. This member, 32a,
Connect the hoses 34a, 34b whose inner holes communicate with the ends of the conductive pipes 27a, 27b, and connect the hoses 34a, 34b so as to supply water to the necessary cooling parts of the welding machine 1 for cooling.
1) A cooling water channel (not shown) is provided which flows from one side of the welding machine to the other through the welding machine 1. Following the inner holes of the insulating pipes 28a and 2ab terminating within the tip member 20, a second
As seen in the figure, the internal passages 35a, 351) respectively.
are provided and opened on both sides of the tip member 20, and these openings are connected to the air cylinder 15 via a hose 36a136b. In the figure, 37 is an 0 ring.

The cylindrical part 21 of the main shaft structure 2 has its hollow part 39 connected to the conductive pipes 27a, 271) and the insulating pipe 28a12.
81) passing through each other at intervals, as seen in FIGS. 1 to 3. Following this cylindrical portion 21, an insulating member 22, a conductive member 23, an insulating plate 24, and a conductive member 2
5 forms conductive surfaces 40a, 401) that support the pipes 27a, 27b, 28a, 28b together with the tip member 20 and the insulating member 38, and connect to the conductive pipes 27a, 271) separately. are doing. As shown in FIGS. 1 and 3, the conductive pipe 27a is connected to the conductive member 23 by press-fitting it into the hole 41, and the conductive member 25 is connected to the insulating plate 24 and the insulating tube 42.
is insulated. The conductive pipe z7b is the conductive member 2
3 by an insulating cylinder 43, and is connected to the conductive member 25 by being press-fitted into the hole 44 thereof. Furthermore, the insulating pipes 28a, 281) simply pass through the insulating member 22, the conductive member 23, the insulating plate 24, and the conductive member 25 in parallel to the conductive pipes 27a, 271) at a predetermined distance. are doing.

The insulating member 26 at the base end of the main shaft structure 2 is formed of a non-conductive material into a short cylindrical shape, and has respective ears 27a, 27b, and 28a inside the top and bottom shown in FIGS. 1 and 2.

The ends of 28b are located, and a separate internal passage 45, 46, 47, 48 is bored therein communicating with each end thereof;
Each of the internal passages opens into a respective circumferential groove 49, 50, 51, 52 provided at axially different positions on the outer periphery. In the figure, 53 is a 0 ring.

The main body 3 supports the main shaft structure 2 so as to be rotatable about its shaft, and supports the outer periphery of the cylindrical portion 21 via bearings 54 and 55.

As shown in FIGS. 1 and 3, the rotation drive unit 4 includes a motor 56 having a shaft parallel to the main shaft structure 2 provided in the main body 3;
Bevel gear 57.58, worm 59, worm wheel 6
0, a motor 56 is provided on the main body 3, and a worm wheel/1/60 is provided on the cylindrical portion 21 of the main shaft structure 2. Connected to the shaft 61 of the worm 59 in FIG. 3 is an encoder 62, which outputs an index signal for controlling the rotational position of the main shaft structure 2.

The power rotation connection part 5 is connected to the conductive peripheral surface 4 of the main shaft structure 2.
It consists of oa, cab, contacts ssa and s3b, and a part that supports them on the main body 3 side. Contactor 63a
, 621b are the conductive peripheral surfaces 40a, as shown in FIG.
The conductors are placed on each side so as to contact each other in correspondence with the aob. These contacts 63a, 63b are the fourth contactors 63a, 63b.
As shown in the figure, a pair of conductive levers 65a165
1), and the levers 65a1651) are supported in the middle by conductive fulcrum shafts 66a and s6b, respectively, on the side of the main body 3, as shown in FIG. fulcrum shaft 66a,
66'b is electrically insulated from the main body 3 side by insulating members 67 and 68, but the corresponding v-bars 65a and 6
5b and contacts 63a, 631) are electrically connected. In the figure, 96.97 is a conductive bearing. One end of each of the fulcrum shafts 6ea and sab is extended and connected to a power supply cable via a suitable metal fitting 69a, 691). In FIG. 4, an insulating member 70 is placed between the upper ends of the levers 65a and 65b.
An air cylinder 71 is provided via the air cylinder 71. When the air cylinder 71 is in the shortened state, the lever 65a,
651) to separate the contacts 63a, a3b from the conductive peripheral surfaces 40a, 4ob, and in the extended state contactors 63a, a3b.
631) are brought into pressure contact with the corresponding conductive peripheral surfaces 40a, 40b. Note that this pressure contact is not made while the main shaft structure 2 is rotating. Further, reference numerals 72 and 73 in the figure are water holes for cooling, through which water is passed through a hose (not shown).

The fluid passage rotary connection portion 6 is formed into a groove by the insulating member 26 of the main shaft structure 2 and a cylindrical member 74 fitted around the outer periphery of the insulating member 26 . The cylindrical member 74 has the grooves 49.50.51.5.
Cooling water hose connection parts 75.7 that correspond to and communicate with 2.
6. Pressurized air hose connections 77 and 78 are provided on the outer surface. In the figure, 79 is an O-ring, and 98 is a drain hole. Although this cylindrical member 74 is fixed to the main body 3 side, it is rotatable relative to the insulating member 26 on the main shaft structure 2 side, so that even if the main shaft structure 2 rotates, the hose connection portions 75, 76, 77 .78 and the internal passages 45, 46, 47, 48 are maintained as they are.

A welding machine support device that supports this spot welding machine 1 is used by connecting the main body 3 to the final shaft end 91 of an arm 90 of a robot, as shown in FIG. 6, for example.

A wire group 95 such as a welding power supply cable 92, cooling water supply and discharge hoses 93a, 93b, compressed air supply and discharge hoses 94a, 941) 1 motor power line and control signal line are connected from near the base end of the robot arm 90. It is set up so that it stands up. These are partially bundled and attached to the arm 90 so as to roughly follow the arm 90 and to create slack in appropriate places to accommodate the rotation, bending and stretching of the arm 90, and the tip is attached to a predetermined position on the main body 3 side of the welding machine support device. connected to the parts. That is, the welding power supply cable 92 has positive and negative conductors connected to connection parts 69a, s9b, cooling water supply and discharge hoses 93a and 93b are connected to cooling water hose connections 75 and 76, and compressed air supply and discharge hoses 93a and 93b are connected to cooling water hose connections 75 and 76, respectively. The exhaust hoses 94a and 94b are connected to the compressed air hose connections 77 and 78, and the wire group 95 is connected to the motor 56, encoder 62, etc., respectively. For example, if the cooling water is supplied from the hose 93a and discharged from the hose 93b, the hose connection portion 75, the internal passage 45, the inner hole of the conductive pipe 27a is energized, and the welding machine l is connected via the hose 34a. is supplied to one end of the cooling waterway, returns from the other end to the inner hole of the conductive pipe 27b via the hose 34b, and is discharged through the internal passage 46, the hose connection 76, and the hose 93kl. The compressed air supplied and discharged from the hoses 94a and 94b is supplied to the hose connecting portions 77 and 78, the internal passages 47 and 48, and the insulating pipe 28a, respectively.

Inner hole of 28b, internal passage 35a, 35b1 hose 36
a.

The air is supplied to each chamber of the air cylinder 15 via 36b. On the right side of welding, there are two connection parts 69a, 1691) and 1 contactor 63a, 631) from the cable 92, respectively, for positive and negative connections.
, conductive member 23.25, conductive via 27a,
27 and 11 members 32a, 32'b, l) 1/-De/I/10.1O1E-111,12 are supplied to the electrode tip 13.14. In addition, a supply/discharge path (not shown) for supplying and discharging compressed air to the air cylinder 71 is such that the hoses are bundled together with the hose group, etc., reach the main body 2, and are connected to the air cylinder 71.

In the welding operation for one welding point, the electrode tips 13 and 14 are retracted from each other to a predetermined welding position and the separated electrode tips 13 and 14 are positioned, and then the air cylinder 15 is extended and the tips 13 and 14 are moved to the welded part. This ends with the air cylinder 15 being compressed and the tips 13 and 14 returned to their original separated state. On a production line, this welding operation is typically performed continuously at a large number of different welding locations. If it is necessary to change the orientation of the yoke 11.12 when the electrode tip 13.14 is placed in the welding position, the spindle assembly 2 is rotated by the required angle of rotation. The rotation of the main shaft structure 2 is performed by rotating the motor 56 via bevel gears 57, 58, the worm 59, and the worm wheel /L/60, and the rotation angle is controlled by a signal from the encoder 62. be done. Due to the presence of the power rotation connection part 5 and the fluid passage rotation connection part 6, the welding power supply cable 92 and the cooling water are connected to the main shaft structure 2 side through these to prevent rotation of the main shaft structure 2. The supply hoses 93a, 931) and compressed air supply/discharge hoses 94a, 94b do not rotate. The power rotary connection 5 is configured such that the air cylinder 71 is extended after the tip 13.14 is positioned in the welding position, so that the contacts 63a, 63b are connected to the conductive surfaces 40a, 40b.
are pressed into contact with each other and energized, but even if there is backlash between the worm 59 and the worm wheel #60 used in the rotary drive unit 4, this press-contact state is such that even if there is backlash between the worm 59 and the worm wheel #60 used in the rotary drive unit 4, there is no backlash against the main shaft structure 2 on the main body 3 side. It is in a fixed state without wobbling, the main shaft structure 2 does not move against the impact force when energized, and the positions of the electrode tips 13 and 14 do not move inadvertently and are stable. Furthermore, the heat generated by the conductive parts due to energization is cooled by the cooling water, and in particular, the heat generated by the conductive pipes 27a, 271) in the main shaft structure 2 is effectively cooled because the cooling water flows through their inner holes. Even if the welding operation is continued for a long time, there will be no trouble in the rotation of the main shaft structure 2.

In the above embodiment, details of the current supply path for the tip 13.14 of the welding machine 1 were not shown, but for example, FIG.
) and (to), a configuration in which the welding machine 1 does not use a combustible conductor like the conventional one is advantageous in that the disconnection of the current-carrying path is less likely to occur. 8 in (a) and (to) of the same figure
0 is a conductive bearing, 81.82.83.84 is an insulating member,
85.86 is a shaft member, 87 is a shaft coupling bolt, 88
is a link member, 89 is a bottle, yoke 11 and yoke 121
The piston lodge of the air cylinder 15 of No. 1 is linked and connected.

Although the above embodiment shows a spot welder attached, it is also applicable to supporting other resistance welders.

<Effects of the Invention> According to the present invention, the original degree of freedom of the arm can be improved by attaching the support device main body to the final shaft end of the arm of a robot or special machine that does not have a rotation axis at the tip. In addition to the number of degrees of freedom around one axis, the movement around the l axis is performed as the rotation of the main shaft structure, and the supply of power, cooling water, and compressed air to the welding machine attached to the main shaft structure is rotated from the main body side. Since this is done through the connection part, it is possible to connect the power supply conductor, the cooling water supply and discharge hose, and the compressed air supply and discharge hose to the main body side, so that the rotation of the single-axis rotary shaft is connected to the power supply conductor. This is done without twisting the body, cooling water supply/discharge hose, or compressed air supply/discharge hose. Therefore, the effect of preventing damage to these power supply cables and hoses for supplying and discharging cooling water and compressed air is achieved, and the degree of freedom of turning the l-axis is increased, which expands the scope of work and greatly improves productivity. The effect of improving this can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a partial vertical sectional side view of an embodiment of the present invention, FIG. 2 is a partial sectional plan view of the same embodiment, and FIG. 3 is a line A-A in FIG. 1.
Cross-sectional view, Figure 4 is an enlarged cross-sectional view taken along line B-B in Figure 1, Figure 5 is a cross-sectional view taken along line C-C in Figure 4, and Figure i: J8 is a state in which the device of the same embodiment is attached to the arm of a robot. FIG. 7(a) is an enlarged cross-sectional view taken along line DD in FIG. 1, and FIG. 7 (to) is an enlarged view taken along line E-EUr in FIG. 1...Welding machine (spot welding machine), 2...Main shaft structure, 3...Main body, 4...Rotary drive section, 5...Rotary connection for electric power, 6...For fluid passage Rotating connection, 4oa
, 4ob-・-conductive surface, s3a, 63kl ・
-Contact, 75.76...Hose connection (for cooling water)
, 77.78... Hose connection (for use with compressed air) Patent applicant Delta International Machine Co., Ltd. Agent Tetsu Shimizu and two others Figure 3 Figure 4

Claims (2)

[Claims] (1) A main shaft structure that has a welding machine mounting part at one end and is provided with a power supply passage, a cooling water passage, and a compressed air passage along the longitudinal direction so that each of them reaches the mounting part; a main body that rotatably supports a spindle structure; a rotation drive section provided on the main body to rotationally drive the spindle structure; and a conductive circumferential surface connected to the power supply path on the spindle structure; a power rotary connection part provided with a contact supported on the main body side so as to be in contact with the power supply conductor and connected to the power supply conductor; A support device for a resistance welding machine consisting of a rotary connection for a fluid passage provided with a hose connection on the side. (2) Two cooling water passages are provided, each of which is formed by an inner hole of a conductive pipe member that is electrically insulated from each other, and the power supply path is formed using the pipe member. A support device for a resistance welding machine according to claim (1), characterized in that: