JPH04371397A - Work clamp device in welding machine - Google Patents

Abstract

PURPOSE:To provide a welding machine with a work clamp device by which a small article can be clamped without the influence of a flange size. CONSTITUTION:Concerning the work clamp device for the welding machine, by which a work W is held against a stopper member 13 and fixed; a vertically movable frame 23 which is moved back and forth in the direction orthogonally crossed with the pressing direction of the work W, and a clamping die 35 which is fixed movably on the vertically movable frame 23 to the pressing direction of the work by means of a parallel link mechanism movable in parallel displacement in the pressing direction of the work W are provided. By the expansion and contraction of the parallel link mechanism, the clamping die 35 is moved in the pressing direction of the work W, and the calmping/unclamping of the work W is performed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a workpiece clamping device for a welding machine, and more particularly to a workpiece clamping device for a welding machine that presses and fixes a workpiece against an abutment member in a welding machine or the like.

0002

[Prior Art] In welding machines, especially vertical welding machines, a workpiece clamping device of the type that presses and fixes a workpiece placed on a work table against a barrier-like abutment member has conventionally been used. It has a vertically movable frame that moves up and down at a position in front of the pressing member, and a clamp mold that is provided at the lower end of the vertically movable frame so as to be movable in the pressing direction of the workpiece,
The clamp mold is driven forward by a special hydraulic cylinder device for forward and backward movement to press and fix the workpiece against the abutment member, and the clamp mold is driven backward by the hydraulic cylinder device for forward and backward movement to press and fix the workpiece. The pressing fixation against the abutting member is released.

0003

[Problem to be Solved by the Invention] When the workpiece to be clamped is box-shaped, the clamping die is moved together with the vertically movable frame so that the clamping die is located in a position facing the inner surface of the box-shaped workpiece. It is necessary to enter the box-shaped workpiece through the upper opening, and therefore the box-shaped workpiece needs to have an upper opening large enough to allow the entire vertically moving frame and clamp mold to pass through.

[0004] The dimensions of the clamping die in the above-mentioned workpiece clamping device are determined by the flange dimensions of the box-shaped workpiece, and therefore, as the flange becomes larger, the clamping die also needs to be longer. has become larger,
Accordingly, the upper opening of the box-shaped workpiece is also required to be large. In other words, as the flange size of the box-like workpiece increases, the minimum product size that can be clamped increases, which places restrictions on the size of the box-like workpiece that can be clamped.

The present invention has been made by focusing on the above-mentioned problems in conventional work clamping devices.
It is an object of the present invention to provide a workpiece clamping device for a welding machine that can clamp even small products without being affected by flange dimensions.

[0006]

[Means for Solving the Problems] According to the present invention, in a work clamping device of a welding machine that presses and fixes a work against an abutment member, the work is fixed in a direction perpendicular to the pressing direction of the work. a reciprocating frame that reciprocates, and a clamp mold that is movably attached to the reciprocating frame in a direction in which the work is pressed by a parallel link mechanism that moves in parallel in the direction in which the work is pressed, and that presses the work against the abutting member. This is achieved by a workpiece clamping device for a welding machine characterized by having the following.

[0007]

[Operation] According to the above-described structure, the clamping die moves in the direction of pressing the workpiece by expanding or contracting the parallel link mechanism, thereby clamping or unclamping the workpiece.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below in detail with reference to the drawings.

FIG. 3 shows an example of a vertical automatic welding machine to which a work clamp device according to the present invention is applied. The vertical automatic welding machine 1 includes a base 3 and an upper frame 5 erected on the base 3, and has a work table 7 on the upper surface of the base 3 that supports a box-shaped workpiece W. There is.

A processing head 11 equipped with a welding torch 9 is provided on the upper frame 5 so as to be movable in each of the coordinate axes of the X-axis, Y-axis, and Z-axis.

A pair of barrier-like abutment members 13 are erected on the back side of the work table 7 on the base 3.

An operation box 17 is suspended and supported by an arm 15 on the upper frame 5, and an L-shaped arm 19 located above the work table 7 is provided. Clamp device 2
1 is installed.

The work clamp device 21, as shown in FIG.
The vertically movable frame 23 is engaged with the arm 19 by a guide member 25 so as to be vertically movable.

A fluid pressure cylinder device 27 is attached to the arm 19, and the fluid pressure cylinder device 27 is connected to the vertically moving frame 23 by a cylinder rod 29 so as to reciprocate the vertically moving frame 23 in the vertical direction. It has become.

One end of each of two sets of upper and lower link elements 31 and 33 is pivotally attached to the lower part of the vertically movable frame 23, and each of the link elements 31 and 33 has a vertically long rectangular shape at the other end. A body-shaped clamp mold 35 is pivotally supported.

This constitutes a parallel link mechanism that moves in parallel in the direction in which the workpiece W is pressed against the abutment member 13, and the clamp mold 35 moves the workpiece W against the abutment member 13 by expanding and contracting the parallel linkage mechanism. It will now move parallel to the hitting direction.

A free ball bearing 37 is attached to the bottom of the clamp mold 35.

According to the above structure, as shown in FIG. 1, when the vertically movable frame 23 is in the raised position, the clamp mold 35 hangs down from the vertically movable frame 23 due to its own weight, and the parallel link mechanism is suspended from the clamping frame 23. The mold 35 is in a reduced state close to the vertically movable frame 23. In this state, the vertically moving frame 23 is moved by the fluid pressure cylinder device 27.
Then, the entire clamp mold 35 is lowered. As a result of this descent, the vertically movable frame 23 and the clamp mold 35 enter the inside of the work W through the upper opening Wo of the work W on the work table 7, and as shown by the imaginary line in FIG. The free ball bearing 37 at the bottom of the mold 35 comes into contact with the bottom surface Wb of the workpiece W.

As a result, when the vertically movable frame 23 is further lowered by the fluid pressure cylinder device 27, the clamp mold 35 is moved onto the bottom surface Wb of the workpiece W by the free ball bearing 37, as shown in FIG. Since the parallel link mechanism is enlarged and the free ball bearing 37 slides on the bottom surface Wb of the workpiece W, the workpiece W is moved parallel to the abutment member 13 in a direction approaching the abutting member 13. 13. As a result, the workpiece W is clamped.

When unclamping the workpiece W clamped as described above, the vertically movable frame 23 is raised by the fluid pressure cylinder device 27. As the vertically movable frame 23 rises, the clamp mold 35 is drawn to the vertically movable frame 23 while sliding on the bottom surface Wb of the workpiece W while reducing the parallel link mechanism, and is lifted by the vertically movable frame 23 and lowered. In the same state as before, the workpiece W passes through the upper opening Wo and advances to the upper side of the workpiece W.

Although the present invention has been described in detail with respect to specific embodiments above, the present invention is not limited thereto, and various embodiments are possible within the scope of the present invention. This will be obvious to those skilled in the art.

[0022]

As can be understood from the above explanation, according to the work clamping device of the present invention, the parallel link mechanism is reduced and the clamp mold is brought into a compact state by being drawn to a reciprocating frame such as a vertically moving frame. The parallel link mechanism expands only when clamping, and the clamp mold is positioned in a position protruding from a reciprocating frame such as a vertical motion frame in the direction of pressing the work, and the work is pressed against it. Clamping is performed by pressing against the component,
Even if the opening of the workpiece is small regardless of the flange size, the clamp mold can enter into the workpiece, and small products can be clamped without being affected by the flange size.

Furthermore, there is no need to provide a special drive device such as a fluid pressure cylinder device for driving the clamp mold in the pressing direction of the workpiece, and the drive system and control system can be simplified.

[Brief explanation of drawings]

FIG. 1 is a side view showing an embodiment in which a work clamping device according to the present invention is applied to a vertical automatic welding machine.

FIG. 2 is a side view showing the workpiece clamping device according to the present invention in a clamped state.

FIG. 3 is a perspective view showing an example of a vertical automatic welding machine to which a work clamp device according to the present invention is applied.

[Explanation of symbols]

1 Vertical automatic welding machine 3 Base 5 Upper frame 7 Work table 9 Welding torch 11 Processing head 13 Abutting member 21 Work clamp device 23 Vertical movement frame 27 Fluid pressure cylinder device 31, 33 Link element 35 Clamp mold

Claims (1)

[Claims] Claim 1: A workpiece clamping device for a welding machine that presses and fixes a workpiece against an abutting member, comprising: a reciprocating frame that reciprocates in a direction perpendicular to the pressing direction of the workpiece; and a reciprocating frame that is parallel to the pressing direction of the workpiece. 1. A workpiece clamping device for a welding machine, comprising a clamping die that is movably attached to the reciprocating frame in the direction of pressing the workpiece by a moving parallel link mechanism and presses the workpiece against the abutting member.