Automatic welding machine

Patent metadata

Field	Value
Publication number	US-9855621-B2
Application number	US-201615155577-A
Country	US
Kind code	B2
Filing date	May 16, 2016
Priority date	Nov 22, 2013
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

Automatic welding machine includes: a welding torch mounted to a link actuation device set on a mount; and a one-or-more-axes linear motion actuator which causes the link actuation device to advance and retract relative to the mount. The link actuation device includes: a proximal end side link hub disposed on the mount; a distal end side link hub to which the welding torch is mounted; and three or more link mechanisms configured to couple the distal end side link hub to the proximal end side link hub. Each link mechanism includes proximal side and distal side end link members and an intermediate link member. Two or more link mechanisms are each provided with a posture changing actuator which arbitrarily changes the posture of the distal end side link hub relative to the proximal end side link hub.

First claim

What is claimed is:

1. An automatic welding machine comprising a link actuation device,
the link actuation device including:
a proximal end side link hub;
a distal end side link hub; and
three or more link mechanisms which each couple the distal end side link hub to the proximal end side link hub such that a posture of the distal end side link hub can be changed relative to the proximal end side link hub, wherein
each of the link mechanisms includes:
a proximal side end link member having one end rotatably coupled to the proximal end side link hub;
a distal side end link member having one end rotatably coupled to the distal end side link hub; and
an intermediate link member having opposite ends rotatably coupled to other ends of the proximal side end link member and the distal side end link member, respectively,

each of the link mechanisms has such a shape that a geometric model of the link mechanism represented by straight lines shows symmetry between a proximal end side portion thereof and a distal end side portion thereof with respect to a center portion of the intermediate link member, and
two or more link mechanisms among the three or more link mechanisms are each provided with a posture changing actuator which arbitrarily changes the posture of the distal end side link hub relative to the proximal end side link hub,

the link actuation device being disposed on a mount while the proximal end side link hub is directly or indirectly fixed to the mount,
a welding torch being mounted to the distal end side link hub, and
the link actuation device being provided with both or either one of a one-or-more-axes linear motion actuator which causes the link actuation device to advance and retract relative to the mount, and a one-or-more-axes linear motion actuator which causes a workpiece to advance and retract relative to the mount, the workpiece serving as a target to be subjected to welding work performed by the welding torch.

2. The automatic welding machine as claimed in claim 1 , wherein
a point where a central axis of a revolute pair between the proximal end side link hub and each proximal side end link member and a central axis of a revolute pair between each proximal side end link member and the intermediate link member cross each other is referred to as a proximal end side spherical link center, and a straight line that passes the proximal end side spherical link center and that crosses the central axes of the revolute pairs between the proximal end side link hub and each proximal side end link member at a right angle is referred to as a proximal end side link hub central axis, and
the one-or-more-axes linear motion actuator causes the link actuation device or the workpiece to advance and retract on a plane perpendicular to the proximal end side link hub central axis.

3. The automatic welding machine as claimed in claim 1 , wherein
a point where a central axis of a revolute pair between the distal end side link hub and each distal side end link member and a central axis of a revolute pair of each distal side end link member and the intermediate link member cross each other is referred to as a distal end side spherical link center, and a straight line that passes the distal end side spherical link center and that crosses the central axes of the revolute pairs between the distal end side link hub and each distal side end link member at a right angle is referred to as a distal end side link hub central axis, and
the welding torch is mounted to the distal end side link hub such that a central axis of a leading end portion, of the welding torch, which performs welding work onto the workpiece is aligned with the distal end side link hub central axis.

4. The automatic welding machine as claimed in claim 1 , wherein the welding torch is mounted to the distal end side link hub such that a leading end portion, of the welding torch, which performs welding work onto the workpiece faces the proximal end side and protrudes to the proximal end side relative to the proximal end side link hub.

5. The automatic welding machine as claimed in claim 1 , further comprising a wire supply device that automatically supplies a welding rod to the welding torch.

6. The automatic welding machine as claimed in claim 1 , wherein
a point where a central axis of a revolute pair between the distal end side link hub and each distal side end link member and a central axis of a revolute pair of each distal side end link member and the intermediate link member cross each other is referred to as a distal end side spherical link center, and a straight line that passes the distal end side spherical link center and that crosses the central axes of the revolute pairs at a right angle is referred to as a distal end side link hub central axis, and
the welding torch is mounted to the distal end side link hub via a torch advancing and retracting linear motion actuator which advances and retracts along the distal end side link hub central axis.

7. The automatic welding machine as claimed in claim 1 , wherein on each of the proximal end side and the distal end side, in the link actuation device, an angle between the central axis of the revolute pair between the link hub and each end link member and the central axis of the revolute pair between each end link member and the intermediate link member is less than 90°.

8. The automatic welding machine as claimed in claim 1 , wherein the welding torch has a curved portion, and a part of the welding torch is disposed between any two link mechanisms among the three or more link mechanisms.

Assignees

• Ntn Toyo Bearing Co Ltd

Inventors

• Isobe Hiroshi
• Sakata Seigo
• Nishio Yukihiro
• Yamada Hiroyuki

Classifications

• B23K37/0241

  Attachments between the welding or cutting element and the carriage · CPC title

• B23K26/0884

  in at least three axial directions, e.g. manipulators, robots · CPC title

• B23K9/287 Primary

  Supporting devices for electrode holders · CPC title

• B23K9/007

  Spot arc welding · CPC title