Table spot welding machine

Abstract

The present invention provides a table spot welding machine that can quickly and easily place heavy or large objects to be welded onto the table electrode without requiring significant effort. [Solution] The table spot welding machine 1 includes a cylindrical roller 15 having a length approximately the same as the length of one side of the table electrode 10 on the welding worker placement area 10a side, and a support member 16 that separates the roller 15 from the welding worker placement area 10a side of the table electrode 10, and ensures that the vertex position of the roller 15 perpendicular to the surface of the table electrode 10 is approximately the same as the surface position of the table electrode 10, and further supports the roller 15 so that it can rotate freely around its axis. The roller 15 is made of metal and has an elastic member on its surface.

Description

Technical Field

[0001] The present invention relates to a table spot welder including a table electrode on which a workpiece (referred to as a "work") is placed, and a welding gun which is an electrode paired with the table electrode.

Background Art

[0002] [[ID=((12))]]As the above-described table spot welder, for example, there is one previously proposed by the inventors of the present application (see Patent Document 1).

[0003] Like the table spot welder described in Patent Document 1, the table electrode has a rectangular flat plate shape and is disposed on the housing of the table spot welder. The table electrode can be adjusted in position in the vertical direction by a vertical movement mechanism (not shown).

[0004] On the other hand, the welding gun is an electrode paired with the table electrode, and includes those having a shape called a "horizontal gun" and those having a shape called a "vertical gun". The horizontal gun is supported so as to be movable in a horizontal posture parallel to the table electrode, and the vertical gun is supported so as to be movable in a vertical posture orthogonal to the table electrode. The horizontal gun can also move in the vertical direction, and the vertical gun can also move in the horizontal direction.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the conventional table spot welding machines described above, when handling heavy or large objects to be welded on the table electrode, it requires considerable effort, and the time it takes to place the object on the table electrode results in poor work efficiency.

[0007] This invention has been made in view of the above circumstances, and aims to provide a table spot welding machine that can place heavy or large objects to be welded onto the table electrode in a short amount of time without requiring much effort. [Means for solving the problem]

[0008] The present invention relates to a table spot welding machine comprising a rectangular flat table electrode on which a workpiece is placed and which is disposed perpendicular to the height direction of the housing of the table spot welding machine, and a welding gun which is an electrode paired with the table electrode, wherein the table spot welding machine comprises a single cylindrical or cylindrical roller, and a support member which separates the roller from the table electrode, and which supports the roller so that the vertex position of the roller perpendicular to the surface of the table electrode is substantially the same as the surface position of the table electrode, and further supports the roller so that it can rotate freely about its axis.

[0009] With the above configuration, when placing the workpiece on the table electrode, the workpiece can be easily fed to the table electrode by placing it on the roller. In other words, even if the workpiece is heavy or large, it can be placed on the table electrode in a short time without requiring much effort.

[0010] In the above configuration, one roller is arranged on one of the two opposing sides of the table electrode and one on the other, and two support members are arranged corresponding to each of the two rollers.

[0011] With the above configuration, two rollers are arranged corresponding to two opposing sides of the table electrode, and two support members are provided to support each roller. This allows multiple workpieces to be continuously fed from one side of the two opposing rollers to the other side.

[0012] In the above configuration, the roller is made of metal, and an insulating elastic member is provided on the surface of the metal roller.

[0013] With the above configuration, the elastic member acts as a cushioning material, preventing damage to the workpiece and also preventing noise. Furthermore, because the elastic member has insulating properties, it prevents electric current from flowing through the roller. [Effects of the Invention]

[0014] According to the present invention, even if the workpiece to be welded is heavy or large, it can be placed on the table electrode in a short time without requiring much effort. [Brief explanation of the drawing]

[0015] [Figure 1] Side view showing the external appearance of a table spot welding machine according to an embodiment of the present invention. [Figure 2] Figure 1 is a perspective view showing the external appearance of a table spot welding machine. [Figure 3] Figure 1 is a side view showing the tip of the welding gun, roller, and support member of a table spot welding machine. [Figure 4] Figure 1 is a side view showing the conveying state of the workpiece in a table spot welding machine. [Figure 5] A plan view showing an example where three rollers are arranged in series, as shown in Figure 1. [Figure 6] A side view showing a roller member having a spherical roller and a support member that supports the roller member. [Figure 7] Plan view showing an example where three support members are positioned on the welding worker side of the table electrode.

Best Mode for Carrying Out the Invention

[0016] Hereinafter, preferred embodiments for carrying out the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view showing the appearance of a table spot welder 1 according to an embodiment of the present invention (hereinafter referred to as "this embodiment"). Further, FIG. 2 is a perspective view showing the appearance of the table spot welder 1 of FIG. 1.

[0017] In FIGS. 1 and 2, the table spot welder 1 according to this embodiment includes a cooling unit 2, a power supply unit 3, a support post 4, a support arm (a cantilever multi-joint arm) 5, a gun bracket 6, a welding gun 7, a pressurizing cylinder 8, a conductive cable 9, a table electrode 10, a table drive unit 12, and a roller 15.

[0018] The table spot welder 1 according to this embodiment includes only a welding gun 7 called a horizontal gun, but it may include only a welding gun 7 called a vertical gun, or may include both a horizontal gun and a vertical gun. In addition to the horizontal gun and the vertical gun, there are C guns and the like for the welding gun, and the table spot welder 1 according to this embodiment may include any of them.

[0019] The cooling unit 2 supplies cooling water for cooling the heat generated from the welding gun 7 during welding, and operates constantly while the power is on to circulate the cooling water between the welding gun 7. The power supply unit 3 converts the three-phase AC power supplied from the power receiving equipment (not shown) into DC by a rectifying element (not shown), and generates high-frequency AC from the converted DC. The support post 4 is erected vertically in the vicinity of the cooling unit 2 and the power supply unit 3, and supports the support arm 5 so as to be rotatable in the horizontal direction. The support arm 5 includes horizontal arm portions 5A and 5B extending in the horizontal direction with respect to the support post 4, a rotating shaft 5C connecting the horizontal arm portions 5A and 5B so as to be rotatable in the horizontal direction, and a rotating shaft 5D supporting the gun bracket 6 at the tip of the horizontal arm portion 5B so as to be rotatable in the horizontal direction.

[0020] The rotating shaft 5D of the support arm 5 is attached to the tip portion of the horizontal arm 5B. The rotating shaft 5D supports the gun bracket 6 so as to be rotatable in the horizontal direction. The gun bracket 6 has a substantially L-shaped configuration with a bent tip portion as shown in the figure. The base end portion 6a of the gun bracket 6 is attached to the rotating shaft 5D.

[0021] A chain (“chain”, not shown) is built into the gun bracket 6, one end of which is connected to the pressurizing cylinder 8, and the other end of which is connected to the force point portion (not shown) of the welding gun 7. The pressurizing cylinder 8 is attached to the upper end of the rotating shaft 5D. The pressurizing cylinder 8 is rotatable together with the gun bracket 6 by the rotating shaft 5D.

[0022] As the pressurizing cylinder 8 moves in a direction that pulls up the chain inside the gun bracket 6, the rear end of the welding gun 7 is raised in the height direction of the housing 1A of the table spot welding machine 1 (the housing on which the table electrode 10 is placed). At the same time, the tip of the welding gun 7 is pulled down in the opposite direction to the height direction of the housing 1A of the table spot welding machine 1, and presses against the table electrode 10. In this way, the pressurizing cylinder 8 moves in a direction that pulls up the chain inside the gun bracket 6, causing the welding gun 7 to rotate and press its tip against the table electrode 10. The contact of the welding gun 7 with the table electrode 10 is performed just before welding begins (i.e., just before welding current is supplied) and is released after welding is completed. The structure for taking in air into the pressurizing cylinder 8 will not be explained.

[0023] The welding gun 7 consists of a gun body 71 and a shank holder 7 attached to the tip of the gun body 71. The device comprises: 2, a handle 74 attached to the rear end of the gun body 71, a spring coil 7C for raising the rear end of the gun body 71 in the height direction of the housing 1A of the table spot welding machine 1, a shank (not shown) attached to the tip of the shank holder 72, and an electrode tip (not shown) attached to the tip of the shank.

[0024] The spring coil 7C is stretched between the rear end portion of the welding gun 7 and the lower end portion of the gun bracket 6, biasing the rear end portion of the welding gun 7 upward (in the height direction of the housing 1A of the table spot welding machine 1). Since the welding gun 7 is supported by the horizontal arm portion 5B with its approximate center as the pivot point, the vertical trajectory of the tip portion of the welding gun 7 is arc-shaped. The welding gun 7 is biased by the spring coil 7C stretched between the rear end portion and the gun bracket 6 so that the rear end portion is lifted upward. The compressive force of the spring coil 7C allows the welding gun 7 to move up and down easily.

[0025] The welding gun 7 is equipped with a handle 74 on its rear end, which has a lever-type activation switch (not shown) and is used to move the welding gun 7 up and down. The activation switch on the handle 74 outputs a welding command, and when the handle 74 is gripped, the switch is turned on and a welding command is output. The welding command output by operating the activation switch on the handle 74 is taken up by the power supply unit 3. Upon receiving the welding command, the power supply unit 3 starts operating and outputs high-frequency AC. The high-frequency AC output from the power supply unit 3 flows to the primary coil of a welding transformer (not shown).

[0026] The shank holder 72 is formed in the shape of a rod with its tip bent at approximately a right angle, and has a flow channel (not shown) for circulating cooling water inside. The conductive cable 9 connects the power supply unit 3 and the welding gun 7. High-frequency alternating current generated by the power supply unit 3 flows to the welding gun 7 through the conductive cable 9. The table electrode 10 is formed in the shape of a rectangular flat plate and places the workpiece 11 on it. As shown in Figure 1, the table electrode 10 is arranged in a part of the housing 1A of the table spot welding machine 1, perpendicular to the height direction of the housing 1A.

[0027] Here, as shown in Figure 2, the width direction of the table electrode 10 is defined as the "W direction," and the depth direction is defined as the "D direction." The table electrode 10 is mainly made of copper plate. The table drive unit (vertical movement mechanism) 12 moves the table electrode 10 in the vertical direction.

[0028] The roller 15 is used to place the workpiece 11 onto the table electrode 10. As shown in Figure 2, the roller 15 has a cylindrical shape with a length approximately the same as the length of one side of the table electrode 10 on the worker placement area 10a side (the length of the table electrode 10 in the W direction).

[0029] The roller 15 is rotatably supported at one end by a support member 16 (see Figure 3) (rotation around its axis), and at the other end by a support member (similar to support member 16, and therefore not shown in the figure). The roller 15 is positioned away from the worker placement area 10a relative to the table electrode 10, and its vertex position perpendicular to the mounting surface of the housing 1A of the table spot welding machine 1 is at the same level as, or slightly above, the surface position of the table electrode 10. The support members 16, etc., are fixed to the housing 1A side of the table spot welding machine 1.

[0030] Figure 3 is a side view showing the tip of the welding gun 7, the roller 15, and the support member 16 of the table spot welding machine 1. In the figure, the support member 16 comprises two mounting brackets 161 and 162, two bolts 163 and 164, and two nuts 165 and 166. Mounting bracket 161 supports one end of the roller 15. Mounting bracket 162 fixes mounting bracket 161 to the housing 1A of the table spot welding machine 1. Insulation is maintained between the mounting bracket 162 and the housing 1A so that they do not conduct electricity.

[0031] The mounting bracket 161 is slidable vertically relative to the mounting bracket 162 (in the height direction of the housing 1A of the table spot welding machine 1 ("H direction")). By sliding the mounting bracket 161 in the H direction relative to the mounting bracket 162, the position of the roller 15 in the H direction relative to the table electrode 10 (i.e., the apex position P1 of the roller 15) can be adjusted. Normally, the apex position P1 of the roller 15 is adjusted to a position slightly above the surface position of the table electrode 10.

[0032] On the side of the mounting bracket 161 that contacts the mounting bracket 162, and on the side of the mounting bracket 162 that contacts the mounting bracket 161, two elongated through holes (not shown) are formed parallel to each other. The shafts of the bolts 163 and 164 are inserted into these through holes and tightened with nuts 165 and 166, thereby joining the mounting brackets 161 and 162. The other support member is made of the same material as the support member 16.

[0033] When placing the workpiece 11 onto the table electrode 10, the workpiece 11 is placed on the roller 15 and fed in the D direction of the table electrode 10. It goes without saying that the workers involved in the welding operation primarily perform the feeding operation in the worker positioning area 10a. Figure 4 is a side view showing the transport state of the workpiece 11 in the table spot welding machine 1. As shown in the figure, the workpiece 11 is transported in the Y1 direction on the roller 15. By placing the workpiece 11 on the roller 15, even if the workpiece 11 to be placed on the table electrode 10 is heavy or large, it can be placed on the table electrode 10 in a short time without requiring much effort.

[0034] As described above, the table spot welding machine 1 according to this embodiment includes a rectangular flat table electrode 10 on which the workpiece 11 is placed, which is arranged perpendicular to the height direction of the housing 1A of the table spot welding machine 1, and a welding gun 7 which is an electrode paired with the table electrode 10. The table spot welding machine 1 includes a cylindrical roller 15 having a length approximately the same as the length of one side of the four sides of the table electrode 10 that is on the welding worker placement area 10a side, and a support member 16 (there is also another support member) that separates the roller 15 from the welding worker placement area 10a side of the table electrode 10, and the position of the vertex of the roller 15 perpendicular to the surface of the table electrode 10 is approximately the same as the surface position of the table electrode 10, and further supports the roller 15 so that it can rotate freely around its axis. As a result, even if the workpiece 11 is heavy or large, the workpiece 11 can be placed on the table electrode 10 in a short time without requiring much effort.

[0035] Although the present invention has been described with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. Various modifications and applications are listed below.

[0036] (1) The shape of the roller 15 may be cylindrical in addition to a cylindrical shape.

[0037] (2) An elastic material (for example, rubber or urethane resin) may be provided on the surface of the roller 15. This prevents damage to the workpiece 11 and also prevents noise. Furthermore, since the elastic material has insulating properties, it can prevent current from flowing through the roller.

[0038] (3) The length of the roller 15 may be shorter or longer than the length of one side of the table electrode 10 on the worker placement area 10a side.

[0039] (4) The number of rollers 15 is not limited to one. For example, if rollers 15 are provided on all four sides of the table electrode 10, the number of rollers 15 will be "4".

[0040] (5) When two rollers 15 are provided, they can be arranged facing each other to feed the workpiece 11 in an assembly-line fashion.

[0041] (6) If the size of the table electrode 10 is large, it is also possible to arrange multiple rollers 15 in series. Figure 5 is a plan view showing an example in which three rollers 15 are arranged in series. Some table spot welding machines are equipped with both a horizontal gun and a vertical gun, and this type of table spot welding machine has a larger table electrode compared to a table spot welding machine that is equipped with only one of the horizontal or vertical guns. In such cases, one roller that is longer than the roller 15 may be provided, or multiple rollers 15 that are shorter may be provided.

[0042] (7) In addition to cylindrical or cylindrical shapes, the roller 15 can also be spherical. If it is spherical, multiple spheres can be arranged in a straight line. Figure 6 is a side view showing a roller holding member 18 having a spherical roller 19 and a support member 20 that supports the roller holding member 18. Figure 7 is a plan view showing an example in which three support members 20 are arranged on the welding worker placement area 10a side of the table electrode 10.

[0043] In Figures 6 and 7, the support member 20 comprises two mounting brackets 201 and 202, three bolts 203, 204, and 205, and two nuts (not shown). Mounting bracket 201 holds eight roller holding members 18. Mounting bracket 202 fixes mounting bracket 201 to the housing 1A of the table spot welding machine 1. An insulator 21 is provided between the mounting bracket 202 and the housing 1A to prevent electrical conductivity between them.

[0044] The mounting bracket 201 is slidable vertically relative to the mounting bracket 202 (in the height direction ("H direction") of the housing 1A of the table spot welding machine 1). By sliding the mounting bracket 201 in the H direction relative to the mounting bracket 202, the position of the roller holding member 18 in the H direction relative to the table electrode 10 (i.e., the apex position of the roller 19) can be adjusted. Normally, the apex position of the roller 19 is adjusted to be slightly above the surface position of the table electrode 10.

[0045] Two elongated through holes (not shown) are formed parallel to each other on the side of the mounting bracket 201 that contacts the mounting bracket 202, and on the side of the mounting bracket 202 that contacts the mounting bracket 201. The shafts of the bolts 203 and 204 are inserted into these through holes and tightened with nuts (not shown), thereby joining the mounting brackets 201 and 202. Bolt 205 secures the mounting bracket 202 to the housing 1A.

[0046] When placing the workpiece 11 on the table electrode 10, the workpiece 11 is placed on the roller 19 and fed in the D direction of the table electrode 10. By placing the workpiece 11 on the roller 19, even if the workpiece 11 to be placed on the table electrode 10 is heavy or large, it can be placed on the table electrode 10 in a short time without requiring much effort. [Industrial applicability]

[0047] The present invention can be applied to a table spot welding machine, which comprises a table electrode on which the workpiece to be welded is placed, and a welding gun which is an electrode paired with the table electrode. [Explanation of symbols]

[0048] 1 Table spot welding machine 1A enclosure 2 Cooling Units 3 Power supply unit 4 support posts 5. Support Arm 7. Welding gun 10 Table electrodes 10a Welding worker placement area 11 Workpiece to be welded 15,19 Laura 16, 17, 20 Support members 18 Roller holding member 21 Insulator

Claims

1. A rectangular, flat table electrode is provided in a part of the housing of a table spot welding machine, positioned perpendicular to the height direction of the housing, on which the workpiece to be welded is placed. A welding gun, which is an electrode paired with the aforementioned table electrode, In a table spot welding machine equipped with, A single cylindrical or cylindrical roller, A support member is provided to separate the roller from the table electrode, such that the vertex position of the roller perpendicular to the surface of the table electrode is substantially the same as the surface position of the table electrode, and to support the roller so that it can rotate freely about its axis. Equipped with, Table spot welding machine.

2. The roller is made of metal, and an insulating elastic member is provided on the surface of the metal roller. The table spot welding machine according to claim 1.

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