JPS5835025A - Forming method by spinning - Google Patents

Abstract

PURPOSE:To manufacture a high-precision thin tube body with uniform thickness in a spinning forming method, by detecting the deviated thickness pattern of a tube body to be worked from a working force applied to a working roller, and thus controlling the torque of a roller driving motor. CONSTITUTION:A thick cylindrical workpiece 2 is rotated by being fitted to a mandrel 1, and while a motor 5 is rotated,it is allowed to abut on the work piece 2 from one end to start spinning formation. At this time, the pattern output of a load cell 13 which detects a working force applied to the roller 4 due to variation in the thickness of the workpiece 2 is supplied to an arithmetic device 14 and processed according to a preset arithmetic program to supply the output to a torque controller 15. On the basis of this input, the torque of the motor 5 is controlled to regulate the draft of the roller 4, thus obtaining a thin tube body 7 which is free of deviated thickness and has uniform thickness.

Description

[Detailed description of the invention] The present invention relates to a spinning molding method for correcting uneven thickness.

Conventionally, spinning molding is generally used to manufacture thin-walled tubular bodies.In this method, a mantle is inserted into a thick cylindrical workpiece and rotated integrally with the workpiece, and a roller is pressed against the mantle so as to align it with the axis of rotation. This is a method of forming by collecting and moving it. Therefore, although this method is suitable for manufacturing long tubes, it is said to be difficult to obtain highly accurate tubes without uneven wall thickness. This is because the eccentricity of the mandrel, the rotational runout of the device, the non-uniformity of the material, etc. directly affect the size of uneven thickness, and there is currently a limit to the improvement of these precisions.

The present invention has been made in view of the above-mentioned circumstances, and is a spinning forming method that corrects uneven thickness by controlling the rotational torque of the rollers and obtains a highly accurate tube body.

The details of the present invention will be explained below by way of an embodiment with reference to the drawings. The figure shows the configuration of an apparatus for carrying out the method of the present invention. Mandrel (11 to workpiece (2)
are attached and rotated together around the axis (3), and the roller (4) is moved toward the axis (3) in the direction of the arrow (6) while being rotated by the motor (5). As a result, the wall thickness t1 is formed to a smaller wall thickness [2], and a thin tube body (7) is obtained.

The above is similar to the conventional spinning molding apparatus, but the apparatus used in this embodiment is equipped with a control device α. This is a part that estimates the uneven thickness of the butter 7 from the pattern of the processing force applied to the roller (4) K, and controls the torque of the motor (5) based on this. That is, attached to the axis α of the roller (4) is a detector α consisting of nine load cells, an arithmetic device α which inputs the output from the detector I and performs a predetermined calculation,
A torque control device αS receives the output from the calculation device αS and controls the torque of the motor (5).

Next, this embodiment will be described along with its operation. The workpiece (2) is attached to the mandrel (1) and rotated, and the roller (4) is brought into close contact with the workpiece (2) from one end while being rotated by the motor (5). As a result, the roller (4) starts forming, and the processing force applied to the roller (4) is detected by the load cell I. The pattern detected by this method is, for example, as shown in Fig. 8g2, when the cross section of the workpiece point (2) is divided into n equal parts and the magnitude of the machining force at each division is connected. It becomes a pattern like IA.

The machining force changing in this way is sequentially detected by the load cell α, and its output is input to the arithmetic unit a4.

Here, calculations are performed according to a preset calculation program, and the output is input to the torque control device (l!9).Here, the torque of the motor (5) is controlled based on this human power to lower the roller (4). Adjust the ratio and change the pattern of the 111 line A to mold so that there is no uneven thickness.

The relationship between the output and torque of the load cell a3 and the calculation program are set through experiments, but if forming is completed in multiple passes, the machining force from the load cell during one pass is applied to the workpiece ( 2) Each division point a 1
．． It is preferable to control the torque in the next pass in one section by referring to the pattern obtained by integrating for each generatrix of a 2 , . . . a, . . . 11n.

As detailed above, the spinning forming method of the present invention is configured to detect the uneven thickness of the workpiece and control the torque of the roller in accordance with the uneven thickness.

Since the uneven thickness determined by the precision of the spinning device can be corrected separately, a thin-walled cylindrical body with higher precision than before can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of an apparatus for explaining one embodiment of the present invention, and FIG. 2 is an explanatory diagram of a pressurized cover turn in the same embodiment. (1): Mandrel, (2nd workpiece, (3) 2 axes, (4) 2 rollers. Agent Patent attorney Noriyuki Chika (and 1 other person) 11" Figure 2 αtL ri' (2z

Claims (1)

[Claims] In a spinning forming method, a mantle is inserted into a cylindrical knee to be applied, and while these are rotated, a roller is pressed against the workpiece and moved in the axial direction of the rotation to form the workpiece. A spinning forming method 0 characterized in that the uneven thickness of the object is detected and the rotational torque of the roller is controlled in response to this uneven thickness.