JP2002239998A - Deformation preventing method for working model in hot wire type working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily eliminate the problem when a foaming resin material is to be cut by a heating wire with a conventional technique such that the mass of the cut-off portion increases to result in dangling, and proceed with the cutting process as it is precisely. SOLUTION: The heating wire 1 folded in a linear shape to suit the contour of the surface of any product is abutted to the side face of thermoplastic resin material 3 in a block shape installed on a movable table 4, which is moved while the resin material 3 is melted, and a model is cut out from the resin material and subjected to a shaping process. In this method, cutting is conducted while the resin material portion 3b in block shape cut off by the heating wire 1 from the portion 3a extended from the edge of the table 4 is fixed by a jig 5 to the resin material portion 3c in block shape remaining on the table 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing deformation of a working model in a hot-wire type working machine.

[0002]

2. Description of the Related Art When a casting model is formed from a thermoplastic material, for example, a thermoplastic expanded polystyrene block, as shown in FIGS. 5 and 6, a heating wire 1 formed linearly and bent along the surface contour of a product is used. The two ends 1a, 1a are attached to the holders 2, 2 and are heated to abut against the block-shaped thermoplastic material 3 while melting the portion of the thermoplastic material 3 touching the heating wire 1. It is known that a target model is cut out and molded from the thermoplastic material 3 by rotating or translating the table 4 (the illustrated example shows the case of rotational movement). In the figure, reference numeral 2a denotes an arm that supports the holder 2.

In a molding method using this apparatus, a solid having an arbitrary shape can be easily formed only by pressing a heated hot wire 1 against a thermoplastic material 3, and a complicated three-dimensional shape can be easily formed. It has the advantage of being able to.

[0004] Therefore, there is an advantage that molding can be very easily performed even at the cost of a model for making a mold for a deformed tube, and that it can be manufactured at low cost. In addition, since the cutting is performed by using heat melting, there is an advantage that dust and noise are not generated unlike cutting by a saw or a blade, the processing surface is smooth, and the working environment can be kept clean.

[0005] However, when the raw material is cut by the hot wire processing machine, the block-shaped thermoplastic plastic material 3 is cut.
It is necessary that the outer edge portion 3a along which the cutting line 1 extends vertically protrudes from the edge of the table 4.

In such a state, the material 3 is cut, and when the process starts from the middle stage, the separated portion 3b
7, the mass of the thermoplastic foam plastic material 3 gradually increases, and the cut-off portion 3b hangs down by its own weight as shown exaggeratedly for explanation in FIG. Since the heating wire 1 leans against the concave and convex portions 1b of the heating wire 1, there is a problem that the heating wire 1 is slightly deformed by this force, and the accuracy of the shape of the cut surface is deteriorated.

[0007] Such a problem can be solved by cutting off the cut-off portion 3b every time the heating wire 1 cuts through the material to some extent. In some cases, the above processing cannot always be adopted.

[0008]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and even if the separated portion increases in mass and hangs down, it can be easily eliminated and the cutting can be accurately performed as it is. The task was to make it go.

[0009]

According to a first aspect of the present invention, there is provided a method for preventing deformation of a processing model in a hot-wire type processing machine, wherein a linearly bent heating wire conforming to a product surface contour is provided on a movable table. In a method of cutting and molding a model from the block-shaped thermoplastic material by moving the movable table while melting the thermoplastic material, the model extends from the edge of the table. The block-shaped thermoplastic material cut from the cut portion by the heating wire is cut while being fixed to the block-shaped thermoplastic material remaining on the movable table with a jig. .

Therefore, the part cut off as the cutting progresses is fixed and supported by the jig on the main body of the thermoplastic foam plastic material remaining on the table, so that it is supported in a stable state until the last cutting. .

[0011]

Next, an embodiment of the present invention will be described. FIG. 1 is a plan view of a main part of a hot-wire type working machine showing an embodiment of the method of the present invention, and FIG. 2 is a side view of the same main part.

In the method of the present invention, as shown in FIG. 1, when a thermoplastic material 3 such as a block-shaped material made of expanded polystyrene resin is cut by a heating wire 1 using a conventional hot wire processing machine, At a stage where the cutting has progressed to some extent, as shown in FIGS.
A jig 5 having a U-shape is laid over the portion 3c remaining on the table 4 and is fixed to and supported by the thermoplastic material 3c remaining on the table 4.

The jig 5 includes a pair of erection arms 5a, 5a applied along the upper and lower surfaces of the material 3, a bolt rod 5b connecting one end of the erection arm 5a, and a jig 5 connected to the bolt rod 5b. A nut 5c for fixing the arm 5a via a washer 5d.

When the jig 5 is attached, first, the bolt rod 5 is attached to one of the erection arms 5a.
b is fixed with a nut 5c and a washer 5d, and then applied from the lower surface so as to be bridged between the cut-off portion 3b and the thermoplastic material 3c on the table. The bolt rod 5b is inserted through one end of the bolt rod 5b, and is applied from the upper surface so as to be bridged between the cut portion and the thermoplastic material 3 on the table. The U-shaped jig 5 is formed by tightening, and the cut thermoplastic resin material 3 is held.

The droop due to the weight of the cut-off portion becomes extreme around a rotation angle of about 90 ° from the start of the cut, so that taking this into account, as shown in FIG. ° After rotation, one place,
Next, one further portion is provided at a portion rotated 135 ° to 150 ° after further cutting, and a rotation angle is provided every 45 ° to 90 °.

By fixing the jig, it is possible to prevent the thermoplastic material 3a from sagging after cutting, and to perform accurate molding. As the structure of the jig 5 in the above embodiment, one of the arms 5e formed in an L shape as shown in FIG.
The other may be a bolt rod 5b provided with a male screw, and another erection arm 5a may be fixed to this by a washer 5d and a nut 5c. Further, as shown in FIG. May be inserted and the interval can be adjusted only by the nut 5c tightened from the outside.

[0017]

As described above, according to the method for preventing deformation of a processing model in a hot-wire type processing machine according to the first aspect, a portion melted and cut by a heating wire is supported by a jig, so that its own weight is reduced. As a result, no excessive force is applied to the heating wire due to the sag, and accurate molding can be performed regardless of the main die or the core.

Further, there is an effect that the structure of the jig is simple and the implementation is easy.

[Brief description of the drawings]

FIG. 1 is a plan view showing an initial stage in an implementation state of a method of the present invention.

FIG. 2 is a side view showing an embodiment of the method of the present invention.

FIG. 3 is a plan view showing an end stage in an embodiment of the method of the present invention.

FIG. 4 is an explanatory side view showing another example of the configuration of the jig used in the embodiment of the method of the present invention. (A) shows the case where an L-shaped jig is used, and (b) shows the case where a spring is used.

FIG. 5 is a partially enlarged side view of a processing section of a conventional hot-wire processing machine.

FIG. 6 is a partially enlarged plan view of a processing section of a conventional hot-wire processing machine.

FIG. 7 is a partially enlarged side view showing an embodiment of a conventional hot-wire processing machine.

FIG. 8 is a partially enlarged side view showing a cutting state of a conventional hot-wire processing machine.

[Explanation of symbols]

 Reference Signs List 1 heating wire 1a end of heating wire 2 holder 2a holding arm 5 jig 5a erection arm 5b bolt rod 5c nut 5d washer

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenjiro Matsumoto 2-26, Ohama-cho, Amagasaki-shi, Hyogo F-term in Kubota Mukogawa Works (reference) 3C021 EA05 3C060 AA05 CF07

Claims (1)

[Claims] 1. A linearly bent heating wire conforming to the surface contour of a product is brought into contact with a side surface of a block-shaped thermoplastic material placed on a movable table and melts the thermoplastic material. In a method of cutting and molding a model from the block-shaped thermoplastic material by moving a movable table, the block-shaped thermoplastic material cut by the heating wire from a portion extending from the edge of the table is formed. And a method for preventing deformation of a processing model in a hot-wire type processing machine for cutting a block-shaped thermoplastic material remaining on the movable table while fixing it with a jig.