JPH0386395A - Method for detecting working dimension in forging machine - Google Patents

Abstract

PURPOSE:To eliminate variation of working dimensions and to improve working accuracy by detecting descending position of a tool at the time of coming into contact with a working material and descending position of the tool at the bottom dead center and detecting the working dimension of the working material based on the detected result. CONSTITUTION:In the case of adjusting the working dimension of the tool 26 a reaction force received at the time of bringing the tip part of the tool 26 into contact with the working material 29 is detected by a load cell 55. On the other hand, the variation value of the tip part of the tool 26 to a rotating angle theta of a crank shaft 1, i.e., the shifting position of the tip part thereof, is detected by a potentiometer 33. Based on this result, by obtaining stroke of the tool 26, the working dimension of the working material 29 executed with the tool 26 is calculated. When the obtd. value is different with the target value, a position adjusting mechanism 8 for the tool is worked by driving a servo motor 7 and a ram 6 fixing the tool 26 is shifted to adjust the working dimensions of the tool 26.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for detecting machining dimensions of a press machine that forges a workpiece by converting rotational motion into reciprocating motion of a tool by using a crank mechanism.

<Prior Art> FIG. 3 is a front view of a conventional rolling press machine, and FIG. 4 is a schematic diagram of a tool position adjustment mechanism.

As shown in FIG. 3, a slide 3 is connected via a connecting member 2 to a crankshaft 1 to which a main wheel motor (not shown) is connected.

A ram 6 is connected to the slide 3 and is supported by left and right columns 4.degree. 5 and is movable up and down. Further, the slide 3 has a built-in tool position adjustment mechanism 8 operated by a servo motor 7.

In this tool position adjustment mechanism 8, as shown in FIG. 1
2 is formed. And each threaded portion 11.12
tapered members 15 each having a suppression surface 13, 14;
, 16 are screwed together. The pressing surfaces 13 and 14 of each of the tapered members 15 and 16 are in contact with the inclined surface 18 of the support member 17 connected to the connecting member 2, while the lower surface is in contact with the ram 6.
I have 1fi. Furthermore, tension coil springs 19 and 20 are stretched between the support member 17 and the ram 6, and a compression coil spring 21 is interposed between each of the tapered members 15 and 16. Further, a worm wheel 22 is fixed to one end of the screw shaft 9, and a worm 23 of the servo motor 7 is engaged with the worm wheel 22.

Then, drive the servo motor 7 to rotate the screw shaft 9 via the worm 23 and the worm wheel 22.
The tapered members 15, 16 move toward and away from each other due to the threaded portions 11.12 cut in opposite directions, and the tapered members 15.1B, i.e., The ram 6 can move up and down.

Further, an upper die 25 and a tool 26 are fixed to the lower surface of the ram 6. On the other hand, a lower die 28 is fixed on a bolster 27 installed on the floor surface, facing the upper die 25, and a workpiece 29 and a stopper plate 30 are placed on the upper die 25.
is placed. Gap sensors 31 and 32 are installed on the ram 6 and the bolster 27 to measure the distance between them.
is installed.

A potentiometer 33 is attached to one end of the crankshaft 1 to detect the rotation angle of the crankshaft 1 and control the main shaft motor.

When processing the workpiece 29, the crankshaft 1 is rotationally driven by the main shaft motor (path shown). As a result, by reciprocating the ram 6 up and down via the connecting member 2 and the slide 3, the workpiece 29 is processed by the tool 26 fixed to the ram 6.

And the machining dimensions of tool 26! 11, first measure the distance 11L0 between the ram 6 and the bolster 27 at the bottom dead center position of the tool 26 using the gap sensor 31. Distance to the tip @L, and from the bolster 27 to the workpiece 29
The pushing amount of the tool 26 is determined by dividing the distance l1lIIL2 to the machined surface. If the obtained value is different from the target value, by driving the servo motor 7, the tool position adjustment nm mechanism 8 moves the ram 6 to which the tool 26 is fixed. Adjust processing dimensions.

<Problems to be Solved by the Invention> In such a pressing machine, heat is generated during processing of a workpiece, and each member may be thermally deformed and expanded. Therefore, the machining dimensions (indentation amount) by the tool 26 during machining
need to be adjusted.

However, in the method of detecting machining dimensions in the conventional rolling press machine described above, the machining dimensions of this tool 26 are detected by the ram 6.
and a gap sensor 31 attached to the bolster 27.
3g, the thermal expansion of the slide 3, ram 6, bolster 27, etc. due to thermal deformation of the rolling press machine is detected, but the thermal expansion of the upper die 25, lower die 28, or tool 26 is also detected. Not done. The upper die 25, the lower die 28, the tool 26, etc. generate the most heat during machining, and their temperature changes significantly. Therefore, this thermal expansion causes a difference between the target machining dimensions and the actual machining dimensions.
This has caused a problem in that the processing accuracy of the rolling press machine is deteriorated.

SUMMARY OF THE INVENTION The present invention is intended to solve these problems, and an object of the present invention is to provide a method for detecting machining dimensions of a rolling press machine, which improves the processing accuracy of the rolling press machine.

Means for Solving the Problems> A method for detecting machining dimensions of a forging machine according to the present invention to achieve the above-mentioned object is a forging machine that forges a workpiece by converting rotational motion into reciprocating motion of a tool using a crank mechanism. By detecting the reaction force that the tool tip receives during forging, the tool lowering position when the tool tip contacts the workpiece and the tool lowering position at the bottom dead center are detected, and based on the detection results, The present invention is characterized in that the machining dimension of the workpiece by the tool is detected.

Function: During forging with a press machine, the reaction force received when the tip of the tool is in contact with the workpiece is constantly detected. Then, when the reaction force occurs, that is, when the tool tip contacts the workpiece, the tool lowering position is detected, and the tool lowering position at the bottom dead center is detected, and based on the detection results, both The machining dimensions of the workpiece by the tool are detected from the difference between the two.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a schematic perspective view of a rolling press machine for carrying out a machining dimension detection method for a rolling press machine according to an embodiment of the present invention, and FIG. It is a graph showing the amount of change. In addition, the same reference numerals are given to the same members as in the conventional art, and redundant explanations will be omitted.

As shown in FIG. 1, in the compressor 51 of this embodiment, a flywheel 54 is connected to the drive shaft of the main shaft motor 52 via a belt 53, and the crankshaft 1 is connected to the flywheel 54. ing. A slide 3 is connected to the crankshaft 1 via a connecting member 2. A ram 6 is connected to the slide 3 and supported by a column (not shown), which is movable up and down. Note that the slide 3 has a built-in tool position adjustment mechanism 8 operated by a servo motor 7, but the structure is almost the same as the conventional one, so a description thereof will be omitted.

Further, a load cell 55 is attached to the connecting member 2 to detect the reaction force of the tool 26 during machining. This load cell 55 transfers the reaction force of the tool 26 to the ram 6 and slide 3 during machining.
This method detects strain as a strain through a sensor, etc., converts it electrically, and measures the force.

An upper die (path shown) and a tool 26 are fixed to the lower surface of the ram 6. On the other hand, the bolster 27 installed on the floor
A lower die 28 is fixed on the top, and a workpiece 29 is placed on this lower die 28.

Note that a potentiometer 33 for detecting the rotation angle of the crankshaft 1 is attached to one end of the crankshaft 1.

When machining is performed, the crankshaft 1 is rotationally driven by the main shaft motor 52. Then, the ram 6 reciprocates up and down via the connecting member 2 and the slide 3,
A workpiece 29 is machined by a tool 26 fixed to the ram 6.

When adjusting the machining dimensions of the tool 26, first, during forging with the forging pressure @@51, the load cell 55 detects the reaction force received when the tip of the tool A26 is in contact with the workpiece 29. On the other hand, the rotation angle θ of the crankshaft 1 is controlled by the tool 2 using the potentiometer 33.
6. Detect the amount of change in the tip, that is, the movement position of the tip.

As shown in Fig. 2, the machining reaction force is generated by the crankshaft 1.
This occurs in the range of angle Δθ over the rotation angle θ1 to 62. Corresponding to this is the moving position of the tip of the tool 26, angle θ is the tool lowering position when the tip of the tool 26 contacts the workpiece 29, and angle θ2 is the tool lowering position at the bottom dead center. I understand that. Therefore, based on the detection result, the stroke of the tool 26 is calculated from the difference between the two, thereby calculating the machining dimension ΔL of the workpiece 29 by the tool 26.

If this calculated value differs from the target value,
Tool position adjustment mechanism 8 by driving the servo motor 7
The tool 26 is operated to move the ram 6 to which the tool 26 is fixed, and the machining dimension of the tool 26 is y41m.

<Effects of the Invention> As described above in detail with reference to examples, according to the machining dimension detection method of the forging press 411 machine of the present invention, when the tool tip contacts the workpiece based on the reaction force received by the tool tip during forging, The machining dimensions of the workpiece by the tool are determined by detecting the lowering position of the tool at the bottom dead center and the lowering position of the tool at the bottom dead center, so there is no variation in the machining dimension by the tool due to thermal deformation of the pressing machine itself. It is possible to improve the processing accuracy of the press machine.

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view of a rolling press machine for carrying out a machining dimension detection method for a rolling press machine according to an embodiment of the present invention, and FIG. A graph showing the amount of change, FIG. 3 is a front view of a conventional rolling press machine, and FIG. 4 is a schematic diagram of the tool position 1111 mechanism. In the drawings, 1 is a crankshaft, 3 is a slide, 6 is a ram, 8 is a tool position WJ adjustment mechanism, 26 is a tool, 27 is a bolster, 29 is a workpiece, 33 is a potency ν meter, 51 is a pressure machine, 55 is a load cell.

Claims (1)

[Claims] In a press machine that forges a workpiece by converting rotational motion into reciprocating motion of a tool using a crank mechanism, the tool tip is Machining dimensions of the rolling press machine, characterized in that the tool lowering position when contacting the workpiece and the tool lowering position at the bottom dead center are detected, and based on the detection results, the machining dimension of the workpiece by the tool is detected. Detection method.