JP2002240059A - Method for shortening developing period of soft urethane molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the developing period of a soft urethane molded article while reducing cost and labor to a large extent. SOLUTION: The method for shortening the developing period of the soft urethane molded article consists of a step S3 for forming three-dimensional design data from the data of the soft urethane molded article provided by a customer, a step S5 for forming NC data for controlling an NC processing machine from the design data, and a step S6 for cutting the soft urethane molded article by the NC processing machine controlled on the basis of the NC data to manufacture a master model for approval.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to various vehicles, for example,
The present invention relates to a method for shortening the development period of a flexible urethane molded product used for seats, various chairs, sofas and the like of aircraft.

[0002]

2. Description of the Related Art In automobile seats and chairs, urethane molded articles obtained by injecting foaming (cast foaming) into a mold with a foaming material adjusted according to its shape and performance are used.

[0003] A soft urethane foam is often used for such a cast and foamed molded product, but its trial manufacture has hitherto been performed by the following procedure. Here, a seat pad of a vehicle will be described as an example.

[0004] First, when a customer develops, for example, a vehicle seat, receives a drawing or data for studying a prototype for studying and confirming its shape and performance, and then manufactures a mold for producing the prototype. In order to do so, a master model for mold production is cut out from a hard urethane foam or the like based on the drawing or data and manufactured. In this case, the mold production master model is made slightly larger than the actual urethane molded product because the soft urethane molded product is slightly shrunk when removed from the mold.

[0005] Next, a mold is manufactured based on the master model, and a foaming material of a flexible polyurethane foam is injected and foamed into the mold to produce a prototype. Attempts were made to determine whether the prototype was comfortable and tactile at the customer's site, actually put it on the seat frame to determine how well it was set, and to fit the armrest into the recess provided in the backrest of the rear seat.
Until the approval to proceed to the next step is obtained, we receive improvement instructions from customers, create improvement drawings and data, make mold production master models, molds, prototypes, etc. The same procedure as described above is repeated.

As described above, conventionally, a mold is actually made,
Unless injection foaming is performed, the most disadvantageous point is that a prototype that can be evaluated cannot be obtained, and the process up to that time requires much cost and labor.

[0007] In the trial production stage, the mold once manufactured may be filled or shaved for small-scale improvement, but the mold is manufactured each time for large-scale repair. . This involves a large increase in outsourcing costs for urethane molded product manufacturers because they are outsourced.

[0008] Then, such a study prototype is repeated several times, and a mold manufactured based on the prototype finally obtained by the customer for the prototype is used as a seat pad for a target vehicle. Soft urethane molded products) are mass-produced.

Here, the flow of the development procedure from trial production to mass production of a conventional soft urethane molded product will be described in detail with reference to FIG.

In FIG. 6, first, in step S41,
Complete data of a seat pad from a customer, for example, a seat maker (hereinafter referred to as an asi maker) requested to manufacture a seat by an automobile maker, to a urethane molded product maker, that is, a three-dimensional model in which a skin is covered on the seat pad and mounted on a frame Receiving data, step S42
After confirming the contents such as the thickness of the skin and the frame shape of this complete data, whether the seat pad is crushed by the assembling of the skin to form a shape, etc., the thickness of the skin is subtracted from the complete data in step S43. Then, three-dimensional design data of the seat pad is created by adding the crushing allowance at the time of assembly. Here, the three-dimensional seat pad design data is shape data that three-dimensionally represents a pad shape to be a urethane molded product to be developed.

If the approval of the assembler is obtained in step S44, the process proceeds to step S45. If the approval is not obtained, the process returns to step S43 to correct or change the three-dimensional design data of the seat pad data.

Thus, at step S44, the third pad
When the customer's approval is obtained for the three-dimensional design data, a two-dimensional drawing (paper) showing the shape of the pad and several cross-sectional views of the data in step S45 when viewed from each angle.
Create If the vehicle maker approves the drawing in step S46, the process proceeds to step S47. If not, the process returns to step S45 to correct or change again.
Create a dimensional drawing.

In step S47, the contents are explained to the master model maker using the two-dimensional drawing created in step S45. In step S48, the master model maker manufactures a mold production master model. In this case, based on the two-dimensional drawing that has been approved by the vehicle manufacturer in step S45, a mold production master model having a seat pad shape is manufactured by manually cutting hard urethane foam. However, in this mold production master model, when a soft urethane molded product is actually manufactured in the mold, a slight amount of shrinkage when removed from the mold and an amount of shrinkage when the mold itself is manufactured are added. Therefore, it is slightly larger than the actual approved seat pad shape (about 10
05-1100 / 1000).

Next, in step S49, the mold manufacturing master model is inspected by the urethane molded product maker, and if approved by the urethane molded product maker, the process proceeds to step S50, and if not approved, the process returns to step S48 and is corrected again. A master model is produced. In step S50, a mold is manufactured from the master model.

Then, the urethane molded article maker purchases the mold from a mold trader and injects a foaming material into the mold in step S51 to produce a soft urethane molded article (seat pad). In step S52, the car maker, the ass maker, and the urethane molded product maker check the shape and the like of the soft urethane molded product (seat pad) for the first time at this stage, that is, check whether the shape is actually put on the frame or covered with the skin, Check the seating comfort, etc., or check the fit by fitting the armrest into the recess provided in the back part of the back seat. If the approval of the car maker is not obtained, the mold is directly cut or piled if the scale of the change is small, and if the scale is large, the process returns to step S43, and the same as described above in order to newly manufacture the mold. Are repeated.

If the customer's approval is obtained in step S52, the process shifts to mass production through each performance / quality examination step in step S53, and the development is completed. If approval is not obtained at this performance / quality examination stage, repair of the mold is performed in the same procedure as described above, but it is unlikely that step S52 will normally be cleared only once, and it will be large or small until approval is obtained. A total of more than 20 renovations have been made, with an average duration of more than 30 days.

[0017]

As described above, in the development of a soft urethane molded product, it is most important that the soft urethane molded product cannot be actually put on a frame or the like and confirmed unless it goes to step S52. Is a disadvantage.
It is because the master model obtained in the conventional step S48 is a cut product of hard urethane foam, and because of the added shrinkage, it is made slightly larger than the actual urethane molded product, and the shape confirmation, etc. Because it is not possible to do

Second, the design is changed each time a problem is found in the confirmation process, and the mold is modified each time to meet the problem, so that the development period until the mass production system is extended becomes longer. In addition, there is a problem that it takes enormous labor and outsourcing costs.

The present invention has been made in view of the above-mentioned circumstances, and a method for shortening the development period of a soft urethane molded product capable of shortening the development period of a flexible urethane molded product and greatly reducing costs and labor. The purpose is to provide.

[0020]

In order to achieve the above object, the present invention shortens the development period of a flexible urethane molded product by the following procedure.

According to the invention corresponding to claim 1, NC data for controlling the NC processing machine is created based on the three-dimensional design data, and the NC processing machine controlled based on the created NC data creates the NC data. It is characterized in that the work material is cut.

According to a second aspect of the present invention, there is provided a step of creating NC data for controlling an NC processing machine based on three-dimensional design data, and control is performed based on the NC data created in this step. Using a soft urethane foam as a processing material with an NC processing machine and cutting it to produce a model for checking the shape, etc., and adding the three-dimensional shrinkage of the mold and urethane molded product to the three-dimensional design data Creating and modifying the NC data of the model for confirming the shape etc. based on this data, and as a processing material by the NC machine based on the NC data modified or recreated in this step. Cutting the hard urethane foam or wood or resin material to produce a mold working master model; and And a step of fabricating a mold for producing a flexible polyurethane molded article from the fabricated mold making master model by-up, urethane foam foaming material is poured into a mold fabricated by this step,
It is characterized by producing a soft urethane molded product.

According to a third aspect of the present invention, there is provided a step of creating three-dimensional tree data based on three-dimensional design data, a step of creating NC data based on the three-dimensional tree data, Cutting a wooden or resin material as a processing material by using an NC processing machine controlled based on the NC data created in the above step to produce a wooden mold, and softer than the wooden mold produced by this step. Producing a mold for producing a urethane molded product, and injecting a urethane foam foam material into the mold produced by this step to produce a soft urethane molded product.

According to a fourth aspect of the present invention, there is provided a method of creating data in which three-dimensional shrinkage of a urethane molded product is added to three-dimensional design data, and creating three-dimensional mold data based on the data. N based on 3D mold data
A step of creating C data, and using a metal material or a resin material as a working material by an NC processing machine controlled based on the NC data created in this step, and directly cutting the same to form a soft urethane molded product And a step of manufacturing a mold for manufacturing the mold. The step of injecting a urethane foam foaming material into the mold manufactured in this step to manufacture a soft urethane molded product.

According to a fifth aspect of the present invention, NC data for controlling an NC processing machine is created based on three-dimensional design data, and NC data controlled based on the NC data is generated.
It is characterized in that a soft urethane foam is used as a processing material by a processing machine, and at least this is cut using an up-cut method to produce a model for confirming the shape and the like.

[0026]

Embodiments of the present invention will be described below with reference to the drawings.

First, a recently developed NC processing machine used in the embodiment of the present invention will be described.

This NC processing machine has an aerostatic spindle device, and can cut various hard to soft working materials by numerical control. The cutting tools include a ball end mill and a flat end mill which are conventionally known. , A milling cutter or the like can be used.

The cutting tool is attached to the tip of the spindle supported by the aerostatic spindle device of the NC machine body (not shown). When cutting a hard work material, a cutting tool suitable for the work material may be selected, and when cutting a soft urethane foam, it is desirable to select the following cutting tool.

As shown in FIG. 4, as a cutting tool suitable for cutting soft urethane foam, a rake angle α on the negative side inclined to the rotation direction delay side from a line Q connecting the cutting edge O and the tool center P as shown in FIG.
It is preferable to use a sharp-edged cutting tool having the following.

The pedestal on which the work material of the NC machine is mounted is movable in the X-axis and Y-axis directions, and the cutting tool is driven at a high speed by an aerostatic spindle device while being driven in numerical values in the Z-axis direction. The cutting is controlled.

Here, as an example of the cutting of soft urethane foam by the NC machine equipped with the aerostatic spindle device as described above, NC data when using a ball end mill having a negative rake angle α are listed below. It is as follows.

Rotational speed of ball end mill: 30,000 rpm (peripheral speed of cutting edge: 800 m / min) Size of ball end mill: 10φ (6φ for finishing) Cutting method: Up-cut method Cutting speed: Pedestal (moves in XY directions) = 8 m / min Blade (moves in the Z direction) = 8 m / min However, when cutting a curved surface as a shape, the speed is adjusted to adjust the shape so that the shape comes out.

The cutting speed of the pedestal and the cutting tool is 0.8 m / min during finishing: 10 m / min (speed when moving to the next point where urethane is cut) NC data when cutting such soft urethane Based on the set conditions, the NC spindle machine with an aerostatic spindle machine drives the spindle at a high speed at a cutting edge peripheral speed of 800 m / min or more, and a soft urethane foam is formed by an up-cut method using a cutting tool having a negative rake angle. By cutting, it is possible to cut the flexible urethane foam into a desired shape very smoothly. In this case, sharp cutting can be performed satisfactorily without a large cutting resistance reaching the soft urethane foam and without significantly elastically deforming the cut portion of the cutting blade.

FIG. 5 is an explanatory view showing a cutting method of an up-cut method using a cutting tool of the processing machine.

The cutting by the above-mentioned up-cut method is an upward cutting as shown in FIG. 5, in which a cut is made as shown by a broken line m, and the thickness of the chip gradually increases from 0. Unlike the down-cut method, the cutting blade does not bite into the outer surface n of the flexible urethane foam F in the cutting direction.

On the other hand, if air can be blown to the cutting portion, the cutting chips can be blown off and the cutting portion can be cooled. Thereby, even if the processing is performed for a long time, there is no fear of fire even with flammable soft urethane foam, and the cutting processing can be performed.

If the soft urethane foam used for cutting has a hardness of 25 N (about 2.5 kg / 100 cm ² ) or more, the density and mechanical strength hardly affect the cutting, and it is very good. Since a model for confirming the shape and the like of the cutting surface can be obtained, by selecting a soft urethane foam having physical properties closest to the customer's request, it is possible to confirm substantially the same sitting comfort in addition to the shape. Furthermore, in the case of a sample for simply confirming only the shape, if a material having a higher density and a smaller cell is selected, a urethane processed product having a more beautiful cut surface can be obtained.

It should be noted that NC when cutting soft urethane foam
Under the data setting conditions, the up-cut method with a good surface finish was used as the cutting method. However, when it is desired to operate the NC processing machine efficiently and reduce the time, both the up-cut and the down-cut can be used. .

Next, an embodiment of a method for shortening the development period of a urethane molded product using the above-described NC processing machine will be described.

FIG. 1 is a flow chart showing a procedure according to the first embodiment of the present invention.

In FIG. 1, first, in step S1, complete data of a seat pad is received from a customer, for example, an automobile manufacturer, and in step S2, the contents of the complete data are confirmed. The three-dimensional pad data is created by subtracting the thickness of the frame or the amount of the frame, or adding the crushing allowance at the time of assembly.

In step S4, if approval is obtained from the customer, here, the car maker, the flow proceeds to step S5, and if not, the flow returns to step S3 to correct or change the three-dimensional pad data.

When the customer's approval is obtained for the three-dimensional pad data in step S4, the process proceeds to step S4.
In step 5, NC data for operating the NC processing machine is created. Here, the data which becomes the command of the cutting in the NC processing machine, that is, the setting data such as the pad shape, the moving / cutting speed, the shape of the blade, the size, the number of revolutions, the cutting method, the diameter φ of the blade, and the like described above are created. It is set in a numerical controller (not shown) of the NC processing machine.

Next, in step S6, step S5
The NC processing machine is operated based on the NC data created in the above, and a soft urethane foam closest to the physical properties of the soft urethane molded product required by the customer is cut to produce a model for confirming the shape and the like.

In step S7, if the customer's approval has been obtained for the shape confirmation model manufactured in step S6, the process proceeds to step S8. If the approval is not obtained, the process returns to step S5, and an NC (not shown) The NC data of the processing machine is corrected or changed again, and a model for confirming the shape and the like is manufactured in step S6 as described above.
In this case, the customer confirms the fit of the model for checking the shape and the like by actually placing the model on the frame.

As described above, it is of greatest significance to be able to obtain a model for confirming a shape or the like having the same size and feel as an actual molded product without using a mold, without having to manufacture a mold. It is possible to obtain a model for confirming the shape of the soft urethane foam without manufacturing a mold simply by repeating the creation of pad data, the change of NC data, and the cutting by the NC processing machine as many times as necessary.

When the customer's approval is obtained in step S7 in this way, in order to actually manufacture the mold in step S8, it is anticipated that the shrinkage ratio of the mold and the urethane molded product are matched. Then, three-dimensional additional shrinkage data is created so that the pad becomes approximately 1010/1000 to 1050/1000 times.

In step S9, the NC of the model for confirming the shape etc. which has been approved based on the three-dimensional additional contraction rate data
The data is corrected as described above, and this N
Based on the C data, a hard urethane foam, wood, or resin material is cut by an NC processing machine to produce a mold production master model, and then, in step S11, a mold is produced from this mold production master model. I do.

In step S9, if the correction is so large that it is better to re-create the data than the correction, the data may be re-created.

Thereafter, a foaming raw material of a soft urethane foam is injected and foamed into this mold to start mass production of a soft urethane molded product. At this time, if it is necessary to make more than one mold, a wooden mold is manufactured from the master model, and a mold is manufactured from the wooden mold.

As described above, in the first embodiment of the present invention, when the customer's approval is obtained for the three-dimensional pad data in step S4, based on the three-dimensional pad data in step S5. Since the NC data is created, and the soft urethane foam is directly cut by the NC processing machine at step S6 based on the NC data to produce a model for confirming the shape and the like, a polyurethane molded product is produced as in the prior art. Each time there is a design change, the mold is renovated,
It is not necessary to repeat the procedure of injecting the foaming raw material of the soft urethane foam into the mold each time to make a prototype and confirm it, that is, steps S45 and S46 shown in FIG.
Approximately 20 days related to Step S52 are not required, so that the period of trial production of the urethane molded product can be significantly reduced, and the labor and cost can be greatly reduced.

In particular, in the present embodiment, when the approval of the customer cannot be obtained for the model for confirming the shape and the like manufactured by directly cutting the soft urethane foam by the NC machine, the NC data is corrected or Since it is only necessary to make a change and cut the soft urethane foam again to produce a model for checking the shape and the like, even a large-scale change can be easily dealt with without changing the mold.

FIG. 2 is a flowchart showing a procedure according to the second embodiment of the present invention.

In FIG. 2, when a multi-sided mold is required, such as for mass production determination, three-dimensional tree pattern data is created from three-dimensional pad data in step S13.

Further, in step S14, NC data for controlling the NC processing machine is created based on the tree shape data, and the NC data is set in a numerical control device of the NC processing machine (not shown). Based on the NC data, an NC machine cuts the resin material to directly produce a wooden mold.

Then, in step S16, the mold is transferred to a mold maker. In step S17, the mold maker manufactures a mold from the mold.

As described above, in the second embodiment, after creating three-dimensional tree pattern data, NC processing data is created based on the tree pattern data, and the tree pattern is directly produced by the NC processing machine. Since this wooden mold was handed over to the mold maker, the production of the mold production master model could be omitted, and the first
In addition to the functions and effects of the embodiment, it is possible to reduce the number of days and costs for manufacturing the mold.

FIG. 3 is a flowchart showing a procedure according to the third embodiment of the present invention.

In FIG. 3, after creating pad data in which only the three-dimensional pad shrinkage rate is added to the urethane molded product data in step S8a, three-dimensional mold data is created in step S18.

Further, in step S19, NC data for controlling the NC processing machine is created based on the mold data, and the NC data is set in a numerical control device of the NC processing machine (not shown). Based on the NC data, a die is manufactured by directly cutting an aluminum material by an NC processing machine.

As described above, in the third embodiment, after creating three-dimensional mold data, NC machining data is created based on the mold data, and the mold is manufactured directly by the NC machine. Therefore, the production of the master model for producing the mold can be omitted, and the number of days until the production of the mold can be reduced in addition to the operation and effect of the first embodiment.

Incidentally, the first to third embodiments described above.
In the embodiments of the present invention, what is called a mold refers to a mold obtained by cutting with an NC machine into which a foaming material is injected, and an aluminum mold or a casting mold.

[0064]

As described above, according to the present invention, it is possible to provide a method for shortening the development period of a soft urethane molded product capable of shortening the development period of the flexible urethane molded product and greatly reducing the cost and labor. .

[Brief description of the drawings]

FIG. 1 is a flow chart of a procedure showing a first embodiment for explaining a method for shortening a development period of a soft urethane molded product according to the present invention.

FIG. 2 is a flowchart of a procedure showing a second embodiment for describing a method for shortening the development period of a soft urethane molded product according to the present invention.

FIG. 3 is a flow chart of a procedure showing a third embodiment for explaining a method for shortening a development period of a soft urethane molded product according to the present invention.

FIG. 4 is a diagram showing a cutting edge portion of a cutting tool of the NC processing machine used in the present invention.

FIG. 5 is an explanatory view showing a cutting method of an up-cut method using a rotary tool of the NC processing machine.

FIG. 6 is a diagram showing a flow of a procedure from trial production of a conventional urethane molded product to mass production.

[Explanation of symbols]

 S1: Complete data receiving step from customer S2: Complete data content confirmation step S3: Three-dimensional pad data creation step S4: Customer confirmation step S5: NC data creation step S6: Shape confirmation model creation step S7: Customer Prior confirmation step S8: Three-dimensional shrinkage ratio additional data creation step S9: NC data correction step S10: Mold production master model production step S11 Wood mold production step from master model S12: Mold production step from wooden mold

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) B29K 105: 04 B29K 105: 04 B29L 31:58 B29L 31:58 (72) Inventor Isao Kawasaki 328 Shimokosaka, Kawagoe-shi, Saitama -2 F-term in Toyo Quality One Kawagoe Factory (reference) 4F202 AA31 AG20 CA01 CB01 CD04 CD18 CD28 5B046 AA05 BA08 EA10 5H269 AB05 AB19 AB37 BB01 FF06

Claims (5)

[Claims] An NC data for controlling an NC processing machine is created based on three-dimensional design data, and a machining material is cut by an NC machining machine controlled based on the created NC data. A method for shortening the development period of the characteristic soft urethane molded product. 2. creating NC data for controlling the NC processing machine based on the three-dimensional design data;
A step of using a soft urethane foam as a processing material and cutting the same to produce a model for confirming the shape and the like by using an NC processing machine controlled based on the NC data created in this step; The 3D shrinkage ratio of the mold and urethane molded product is added to the data, and based on this data, the N for the model for confirming the shape etc.
Modifying or recreating the C data, and NC based on the NC data modified or recreated in this step.
Using a hard urethane foam or wood or resin material as a processing material by a processing machine to cut the same to produce a mold production master model, and a softer urethane than the mold production master model produced by this step. Manufacturing a mold for manufacturing a molded article, and injecting a urethane foam foaming material into the mold manufactured by this step to manufacture a soft urethane molded article, How to shorten the development period. 3. A step of creating three-dimensional tree data based on three-dimensional design data, a step of creating NC data based on the three-dimensional tree data, and a step of creating NC data based on the three-dimensional tree data. Using a wood or resin material as a processing material by an NC processing machine controlled on the basis of this to cut a wood pattern, and to manufacture a soft urethane molded product from the wood pattern manufactured by this step. A method for shortening the development period of a soft urethane molded product, comprising: injecting a urethane foam foaming material into the mold produced by this step to produce a soft urethane molded product. 4. A three-dimensional design data containing a urethane molded product 3
Creating data to which a three-dimensional shrinkage rate is added, and creating three-dimensional mold data based on the data;
Creating NC data based on the three-dimensional mold data, and directly using a metal material or a resin material as a processing material by an NC processing machine controlled based on the NC data created in this step. Manufacturing a mold for producing a soft urethane molded product by cutting, and injecting a urethane foam foaming material into the mold produced by this step to produce a soft urethane molded product. To shorten the development period of flexible urethane molded products. 5. Creating NC data for controlling an NC processing machine based on three-dimensional design data, and using a soft urethane foam as a processing material by the NC processing machine controlled based on the NC data. A method for shortening the development period of a soft urethane molded product, characterized in that at least this is cut using an up-cut method to produce a model for confirming a shape and the like.