JPS60115339A - Forming device of head pipe for two-wheel barrow - Google Patents

Abstract

PURPOSE:To form a head pipe for a two-wheel barrow at a low cost by moving forward and backward a pair of drawing dies and burnishing punches against the end part of a work, and executing simultaneously drawing and burnishing. CONSTITUTION:A new work W is held by a gripper 5, and fed in between drawing dies 11, 21 containing burnishing punches 13, 23. The work W is held by moving forward the drawing die 21 of the movable side, and by further moving it forward, both ends of the work W are drawn to a necessary shape. Subsequently, when the burnishing punches 13, 23 are moved backward, the inside surface of both ends of the work W is finished to a necessary size. The drawing die 21 of the movable side has a little smaller diameter than the drawing die 11 of the fixed side, therefore, when the drawing die 21 of the movable side is moved backward in the end, it moves backward in a state that the work W is held, contacts by pressing to the tip of a sleeve 4b of an ejector 4 projected relatively, and discharges the work W.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a head pipe forming apparatus for two-wheeled vehicles, and more particularly to an apparatus for simultaneously performing drawing and burnishing processes.

(Prior Art) Conventionally, head pipes for motorcycles have been molded by moving a mold forward and backward in the axial direction to draw the end of the pipe, and then cutting the inner surface of the end with a cutting tool. For this reason, a process such as loading and unloading the workpiece is required for each process, resulting in the problem that processing costs cannot be reduced as expected.

(Purpose) The present invention was made in view of the above problem, and its purpose is to inexpensively form a head pipe for a two-wheeled vehicle by simultaneously subjecting a pipe material to drawing and burnishing processing. The goal is to provide a new device that can

(Structure) Therefore, details of the present invention will be described below based on illustrated embodiments.

The drawing shows an example of the apparatus of the present invention, and reference numerals 11 and 21 in the drawing indicate a pair of draw dies for narrowing both ends of the workpiece W to required dimensions, one of which is the draw die 1.
1 is integrally fixed to the front surface of a fixed holder 2 fixed to one end of the base l together with a pilot 12 for receiving the tip of the workpiece W, and the other draw die 21 is used to draw the end of the workpiece W to a slightly smaller diameter. shaped so as to be able to
A pilot 2 is installed at the tip of a main piston rod 25 that slides within a main cylinder 24 fixed to the other end of the base l so that it can move forward and backward between the discharge position and the final machining position of the workpiece W.
It is fixed integrally with 2. Reference numeral 13.23 denotes a pair of burnishing punches for finishing the inner surface of the end portion of the work W. One of the burnishing punches is arranged so that it can reciprocate between the processing position and the retracted position independently within each draw die 11.21. 13 is attached via a joint 16 to the tip of a piston rod 15 of a hydraulic cylinder 14 fixed to the rear surface of the fixed holder 2, and the other vanishing punch 23 is attached to a sub-piston rod of a sub-cylinder 26 provided within the main piston rod 25. It is integrally attached to the tip of 27. Reference numeral 4 denotes an ejector for ejecting the molded workpiece W, and its base portion 4a is integrally attached to the front surface of a slide holder 3 provided on the base 1 to slidably support the main piston rod 25. The sleeve 4b is formed to have approximately the same diameter as the end of the workpiece W after molding.
It is integrally attached to this base portion 4a via a long groove 25a bored in the circumferential surface of the piston rod 250, is located within the axis of the main piston rod 25, and its tip is approximately the same as the front surface of the draw die 21 in the retracted position. It extends to the position.

In addition, the reference numeral 13a in the figure indicates a shoulder for locking at the end of the workpiece W formed on the circumferential surface of the vanishing punch 13 of the fixed draw die 11, and 5 indicates a gripper of a rod pot (not shown).

Next, a process for forming a head pipe for a two-wheeled vehicle using the above-mentioned apparatus will be explained.

FIG. 1 shows a state in which a formed work W is discharged and a new work W is received. In this state, the movable draw die 21 is fully retracted, and both vanishing punches 13.23 are located within each draw die 11.21. In this state, when a new workpiece W is held by the gripper 5 and fed between the two draw dies 11 and 21, the movable draw die 21 starts moving forward together with the vanishing punch 23 to hold it (FIG. 2A). Moving further forward, the end drawing process of the workpiece W is performed using both draw dies 11 and 21. During this drawing process, the end of the workpiece W press-fitted into the fixed draw die 11 is positioned by coming into contact with the shoulder 13a provided on the side surface of the vanishing punch 13, so that the movable draw die 21 is positioned in advance. When the stroke advances, both ends of the workpiece W made of a thin-walled pipe are drawn into a desired shape.

Next, from this state, both vanishing punches 13.23
When the workpiece W is retreated (see Figure 2), the inner surfaces of both ends of the workpiece W are finished to the required dimensions, and the entire complex machining process is completed.

By the way, as described above, the movable draw die 21 is formed to have a slightly smaller diameter than the fixed draw die 11, so when the movable draw die 21 is finally moved back, the workpiece W is transferred to the movable draw die along with this retreat. The sleeve 4b of the ejector 4 relatively protrudes from the inside as the movable draw die 21 retreats in the final stage.
It comes into contact with the tip and is ejected (Fig. 1).

In addition, in the above-mentioned apparatus, one of the draw dies is moved as a means for drawing the end of the pipe, but it is also possible to configure both draw dies to move in the axial direction. Other mechanical means such as a cam may also be used as the means.

(Effects) As explained above, according to the present invention, at least one of the pair of workpiece end drawing means is configured to be able to move forward and backward, and a pair of inner surface processing means are arranged within both of the above means so that they can be moved back and forth. Therefore, by retracting the inner surface processing means at the end stage of the drawing process performed by advancing the drawing process means, the drawing and burnishing processes of the motorcycle head pipe can be performed simultaneously, and when the processes are performed separately. By eliminating the work required to attach and detach the workpiece, the processing cost can be significantly reduced.

14. Brief description of the drawings FIG. 1 is a side view of an apparatus showing one embodiment of the present invention, and FIG.
Figures (A) to (C) are explanatory views showing processing steps in the same apparatus.

4...Ejector 11.21...Draw die 13.23...Vanishing punch 14...Hydraulic cylinder 24...Main cylinder 26...Sub cylinder W...Work applicant
Honda Motor Co., Ltd. (1 year old and 7%) Representative Patent Attorney Keiji Nishikawa

Claims (1)

[Claims] A pair of thin-walled pipe-shaped workpiece end drawing means arranged opposite to each other so that at least one can move forward and backward relative to the other, and a pair of inner surface processing means for the workpiece end disposed within the means so as to be able to move forward and backward. A motorcycle head pipe forming device comprising: