WO2019107148A1

WO2019107148A1 - Method for manufacturing sheet pad

Info

Publication number: WO2019107148A1
Application number: PCT/JP2018/042077
Authority: WO
Inventors: 泰輔米澤; 佳之高橋; 由紀子津川
Original assignee: 株式会社ブリヂストン
Priority date: 2017-11-30
Filing date: 2018-11-14
Publication date: 2019-06-06
Also published as: JPWO2019107148A1

Abstract

The present invention provides a method for manufacturing a sheet pad, wherein the method is characterized in that: a recessed part 9 is provided in an upper die 6; an embedding body 3 is temporarily held in the recessed part 9 and thereby positioned and disposed above an intended embedding position by a prescribed amount; foam molding is performed, during which the embedded body is pushed downward by foaming gas that has infiltrated between the embedded body and the inner surface of the recessed part, and the embedded body is moved to the intended embedding position; and a sheet pad in which the embedding body has been integrated in a prescribed position through embedding is obtained. Obtained thereby is a sheet pad having a visually attractive molded surface devoid of any level differences in the interface between a body 1 of the sheet pad and the embedded body 3.

Description

Seat pad manufacturing method

The present invention relates to a method of manufacturing a seat pad used for a vehicle seat or the like, and more specifically, a seed in which the embedded body is embedded and integrated in a main body by setting the embedded body in a mold and performing foam molding. It relates to a manufacturing method for obtaining a pad.

Conventionally, soft or semi-rigid polyurethane foam is suitably used as a seat pad for a vehicle, and the hardness is intended to reduce support stability, safety and comfort, and driver's fatigue. The embedded body is embedded in the seat pad main body in order to adjust the deflection characteristics, the vibration absorbability and the like.

For example, in JP-A-2006-14829 (Patent Document 1) and JP-A-2007-6911 (Patent Document 2), for example, as shown in FIG. There has been proposed a seat pad in which a filling body (embedding body) 3 formed of a foam of relatively high hardness is embedded in the back side of the lower buttocks 2 of the pad body 1 to adjust the above various characteristics. In this case, the insertion body (embedding body) 3 is provided with a recess 4 on the back side of the bottom lower portion 2 of the seat pad main body 1, and a foam member of relatively high hardness separately foam-formed in the recess 4 A method is adopted in which the embedded body 3 is fitted in and adhesively fixed with an adhesive. As prior art documents other than the above-mentioned patent documents 1 and 2, the following

patent documents

3 and 4 are mentioned.

JP, 2006-14829, A Japanese Patent Application Publication No. 2007-6911 WO 2017/018526 JP, 2014-61073, A

In the above-mentioned conventional seat pad, after the foam body of the seat pad body and the embedment body are separately formed separately, the embedded body is fitted in the recess provided in the seat pad body, and the step of bonding the body is necessary. This can be cumbersome and can also increase manufacturing costs.

Therefore, in order to omit the fitting / adhesion step of the above-mentioned embedded body, the embedded body which has been foam-formed in advance is charged into a mold and the sheet pad main body is foam-formed, thereby directly forming the sheet pad during foam molding. It is conceivable to obtain a seat pad in which the embedded body is embedded and integrated in the main body.

That is, as shown in FIG. 5, when the seat pad is foam-formed using a mold provided with the lower mold 5 for forming the seating surface side (surface side) and the upper mold 6 for forming the back surface side, As shown in FIG. 4 (A), the above-mentioned embedded body 3 made of foam molded in advance is set in the upper mold 6, and the raw foam material 8 is injected from the nozzle 7 to the lower mold 5 side. As shown in FIG. 5 (B), the two

molds

5 and 6 are joined, and the embedded body 3 is clamped in a predetermined position in the mold cavity, and the foam raw material 8 is A method of foaming and curing may be considered, whereby it is possible to obtain a seed pad in which the embedding body 3 is embedded and integrated on the back side of the bottom lower portion 2 of the seat pad main body 1 as in FIG. 4 above. It is possible to reduce the manufacturing cost effectively by omitting the fitting / bonding process of the body.

However, in this method, when the foam material is expanded and expanded to fill the cavity of the mold, it is difficult to hold the embedded body 3 at a predetermined position in the design in a predetermined state, for example, as shown in FIG. As shown in FIG. 2, a step 13 is formed at the boundary between the seat pad body 1 and the embedded body 3. In this case, the pad thickness of the lower buttock 2 in which the embedded body 3 is disposed may be reduced, and the design performance may not be obtained.

The present invention has been made in view of such circumstances, and the embedded body is set in a mold, and the foam raw material is injected into the mold to foam-mold, thereby embedding the above-described embedded in a predetermined portion of the seat pad main body. In the case of obtaining a seat pad in which the body is integrally embedded, it is possible to efficiently manufacture a seat pad as designed by preventing as much as possible a step in the boundary between the seat pad body and the embedded body. It is an object of the present invention to provide a method of manufacturing a seat pad that can be used.

The inventors of the present invention conducted extensive studies to achieve the above object, and as a result, when the embedded body is set in the upper mold and the seat pad main body is foam-formed, it occurs at the boundary portion between the seat pad main body and the embedded body. It was found that the step was generated when the foam gas entered between the embedded body and the inner surface of the upper mold during foam molding and pushed down the embedded body. Therefore, as a result of further investigation, it is assumed that a recess is provided at the location where the upper mold is to be placed and the buried body is temporarily fixed to the recess to be set and pressed downward by the pressure of the foaming gas in advance. By disposing the embedded body above the design embedded position, gas generated at the time of foam generation intrudes between the recess and the embedded body and pushes down the embedded body to a predetermined position in the design. The embedded body can be embedded and integrated, and the sheet pad can be reliably manufactured without any step at the boundary between the embedded body and the sheet pad main body, and the conventional insertion / adhesion process can be omitted to improve the production efficiency. It is found that the present invention can be accomplished.

Accordingly, the present invention provides the following method for producing a seat pad.
[1] The embedded body is set in the upper mold of the mold divided into at least upper and lower parts, and the foam raw material is injected into the mold and foam-formed, whereby the embedded body is embedded integrally in a predetermined location of the seat pad body. In a seat pad manufacturing method for obtaining a hardened seat pad,
The upper mold is provided with a recessed portion for temporarily fixing the embedded body, and the embedded body is set by temporarily fixing the embedded body in the recessed portion, and the embedded body is disposed above the designed embedded position by a predetermined amount. After the foam raw material injected into the mold foams and expands and the foam molded body reaches the embedded body, the embedded body is pushed down by the foaming gas which has entered between the inner surface of the recess and the embedded body. A method of manufacturing a seat pad, wherein the seat body is moved to a design embedded position, and the embedded body is embedded and integrated at a predetermined position.
[2] The method for manufacturing a seat pad according to [1], wherein the embedded body is made of a foam foam-formed in advance, and the elastic property of a predetermined portion of the seat pad is adjusted.
[3] The depth of the recess provided in the upper mold is 1 to 3 mm, and the embedded body is set in a state of being temporarily fixed to 1 to 3 mm above the design embedded position [1] [2] The manufacturing method of the seat pad.
[4] The sheet according to any one of [1] to [3], wherein at least a portion of the embedded body to be inserted into the recess is set larger than the recess and the embedded body is temporarily compressed in the compressed state. Pad manufacturing method.
[5] The method for producing a seat pad according to any one of [1] to [4], wherein the seat pad main body and the embedded body are polyurethane foam.
[6] The method for manufacturing a seat pad according to any one of [1] to [5], wherein the buried site of the buried body is the back surface of the lower end of the seat pad body.

[7] The method for manufacturing a seat pad according to any one of [1] to [6], wherein the recess is shaped along the upper surface shape of the embedded body.

According to the manufacturing method of the present invention, by setting the embedded body in the mold and foaming the seat pad body, the seat pad can be efficiently obtained by omitting the fitting / adhesion step of the embedded body. In addition, a high quality seat pad can be reliably obtained without causing a step at the boundary between the seat pad main body and the embedded body.

In the manufacturing method of this invention, it is a fragmentary sectional view which shows the upper type | mold and embedding body when setting an embedding body to a metal mold | die. In the manufacturing method of this invention, it is a fragmentary sectional view which shows the state which set the embedding body to the upper mold | type of a metal mold | die. In the manufacturing method of this invention, it is a fragmentary sectional view which shows the relationship between the upper mold | type of a metal mold | die at the time of foam-molding a sheet | seat pad main body, and an embedding | burying body. The sheet pad which has a structure which embed | buried the embedding | burying body in a sheet | seat pad main body is shown, (A) is a top view, (B) is sectional drawing in alignment with BB of (A). It is a schematic sectional drawing explaining the procedure at the time of setting the embedding | burying body in a metal mold, and foaming-forming a sheet | seat pad main body, (A) shows the state at the time of inject | pouring the foaming raw material before clamping. ) Shows the state after clamping. FIG. 10 is a partial schematic cross-sectional view showing a seat pad foam-formed by a conventional method.

Hereinafter, the method for manufacturing the seat pad of the present invention will be more specifically described with reference to the drawings.

In the method of manufacturing the seat pad according to the present invention, the embedded body 3 is set in the upper mold 6 of the mold and the lower mold 5 side of the mold is the same as the method shown in FIGS. 5 (A) and 5 (B). Then, the foam material 8 is injected into the mold, the mold is clamped, and the foam material 8 is foamed and cured to form the sheet pad body, thereby forming the sheet pad body 1 in the same manner as shown in FIGS. 4 (A) and 4 (B). The embedded body 3 is integrated to obtain a seat pad. In this case, although not particularly limited, the embedded body 3 is integrally embedded, for example, on the back side of the lower end portion 2 of the seat pad main body 1, and the support stability, safety and comfort, the driver Hardness, deflection characteristics, vibration absorption, etc. can be adjusted to reduce fatigue.

The mold includes an upper mold in which the embedded body 3 is set and the back side of the sheet pad is formed, and a lower mold in which the foam material 8 is injected and the seat surface side (surface side) of the sheet pad is formed. And one which is divided into at least upper and lower parts. In this case, the upper and lower molds are not necessarily limited to two divided molds, and the upper and lower molds may be divided into upper and lower molds in some cases. It may be three or more parts having.

The buried body 3 is set in the upper mold 6 of the mold. In this case, according to the present invention, as shown in FIG. 1, a recess 9 is formed at the position of the embedded body of the upper mold 6 along the shape of the embedded body 3, and the embedded body 3 is temporarily fixed in the recess 9. And set. In this case, the line indicated by the alternate long and short dash line 10 in FIG. 1 corresponds to the back surface of the designed seat pad, and as shown in FIG. 2, the embedded body 3 temporarily fixed to the upper die 6 is a single point. It will be in the state located only for the depth h (refer FIG. 1) of the recessed part 9 rather than the design embedding position shown by the chain line 11 by the depth h (refer FIG. 1). In addition, temporary fixing to the said recessed part 9 of the said embedding | burying body 3 can be performed, for example using a suitable pin, a clip, etc.

In this state, similarly to FIGS. 5A and 5B, the foam material 8 is injected from the nozzle 7 to the lower mold 5 side and clamped, and the foam material 8 is foamed and cured to form the sheet pad body 1. Foam molding. At this time, the gas generated along with the bubbling is exhausted through a groove (not shown) provided in the joint portion PL between the upper mold 6 and the lower mold 5, and at that time, the exhaust rate of the gas It is set so as to be maintained at a predetermined foaming pressure. Then, when the foam molding reaches the embedded body 3 and further reaches above the joint portion PL, the foaming gas intrudes between the inner surface of the recess 9 provided in the upper mold 6 and the embedded body 3, as shown in FIG. As shown in FIG. 4, the pressure pushes down the embedded body 3 downward, and the embedded body 3 is moved to the designed embedded position and embedded and integrated in the foam-hardened seat pad body 1. Thereby, a beautiful molding surface without a level difference is obtained at the boundary between the seat pad main body 1 and the embedded body 3.

The depth h (see FIG. 1) of the recess 9 is compared according to empirical rules at the foaming molding site according to the foaming raw material, the foaming ratio, the foaming conditions, the shape of the sheet pad main body 1, the size of the embedded body 3, etc. It can be set as appropriate. Although the depth h of the recess 9 may be appropriately set according to the empirical rule of the site as described above, the depth h is usually about 1 to 3 mm. It is disposed upward by a fixed amount (depth h of the recess 9). The thickness of the embedded body 3 is not particularly limited, but can be 20 to 40% with respect to the seat pad main body 1.

Here, although not particularly limited, it is preferable to use the embedded body 3 in which at least a portion inserted into the recess 9 is set larger than the recess 9, and at least inserted into the recess 9. It is preferable that the compressed portion be temporarily fixed to the recess. Thereby, the buried body 3 can be temporarily fixed more stably. In this case, although not particularly limited, it is preferable to set the width of the embedded body 3 and at least the front and rear, right and left portions of the part inserted into the recess 9 to be larger by 1 to 2 mm than the recess 9 respectively.

The foam forming the seat pad body 1 is not particularly limited, but polyurethane foam is preferably used. Moreover, although there is no restriction | limiting in the material of the said embedding | burying body 3, Usually, the foam foam-formed beforehand is used, In particular, a polyurethane foam is used preferably.

Here, in particular, when the embedded body 3 is embedded on the back surface side of the bottom lower portion 2 of the seat pad main body 1 to adjust the hardness, deflection characteristics, vibration absorbability, and the like of the bottom lower portion 2, it is not particularly limited. However, it is preferable that the seat pad main body 1 forming the seat surface be a soft foam having a relatively low density, and the embedding body 3 be a foam harder than the seat pad main body 1. Although not particularly limited, the polyurethane foam forming the seat pad body 1 and the embedded body 3 has an overall density of 35 to 80 kg / m ³ , particularly 45 to 70 kg / m ³ , and a 25% hardness of 10 to 50 It can be 35 kgf / φ200, in particular 15 to 30 kgf / φ200, and the hardness can be adjusted within this range.

In the present invention, the shape, configuration and the like of the mold and the sheet pad obtained in the method of manufacturing a seat pad are not limited to those shown in FIGS. 1 to 5 and are within the scope of the present invention. Can be changed and adjusted as appropriate.

Hereinafter, an example is shown and an effect of the present invention is shown more concretely.
[Examples 1 and 2, Comparative Example and Reference Example]
Using a mold divided into upper and lower molds, a recess having the depth shown in Table 1 is provided in the upper mold, and a buried body made of a polyurethane foam molded body is temporarily fixed and set in the recess, The foam raw material of the following composition is inject | poured, and a sheet | seat pad is shape | molded on the following conditions. In this case, the width in the front, rear, left, and right of the embedded body is set to be larger than that of the recess by 2 mm, and the embedded body is temporarily fixed to the recess in a compressed state.

With respect to each sheet pad obtained, the boundary between the sheet pad body and the embedded body was examined, and the presence or absence of a level difference was evaluated according to the following criteria. That is, in consideration of the practical influence on the performance of the seat pad, if the step is 2 mm or less, it can be substantially "no step", and when it is evaluated as such, it is as shown in Table 1.

As shown in Table 1, a recess is provided in the upper mold, and the embedded body is temporarily fixed in this recess to foam the sheet pad, which effectively produces a level difference at the boundary between the sheet pad main body and the embedded body. It is understood that it is preventing.

DESCRIPTION OF SYMBOLS 1 Seat pad main body 2 Bottom lower part 3 Buried body 4 Recess 5 formed on back of seat pad main body 5 Lower mold 6 Upper mold 7 Nozzle 8 Foam raw material 9 Concave 10 formed in upper mold A line coinciding with the back surface of the designed seat pad 11 Designing buried position PL Mold joint h Depth of recess

Claims

A sheet in which the embedded body is embedded and integrated in a predetermined location of the seat pad main body by setting the embedded body in the upper mold of the mold divided into at least upper and lower parts, injecting the foam raw material into the mold and foaming. In a method of manufacturing a seat pad to obtain a pad,
The upper mold is provided with a recessed portion for temporarily fixing the embedded body, and the embedded body is set by temporarily fixing the embedded body in the recessed portion, and the embedded body is disposed above the designed embedded position by a predetermined amount. After the foam raw material injected into the mold foams and expands and the foam molded body reaches the embedded body, the embedded body is pushed down by the foaming gas which has entered between the inner surface of the recess and the embedded body. A method of manufacturing a seat pad, wherein the seat body is moved to a design embedded position, and the embedded body is embedded and integrated at a predetermined position.
The method for manufacturing a seat pad according to claim 1, wherein the embedded body is made of a foam foam-formed in advance, and the elastic property of a predetermined portion of the seat pad is adjusted.
The depth of the recessed part provided in the said upper mold | type is 1-3 mm, The said embedding | flush-mounting body is set in the state temporarily clamped 1-3 mm above the embedding position on design. Method of manufacturing seat pad.
The sheet pad according to any one of claims 1 to 3, wherein at least a portion of the embedded body to be inserted into the recessed portion is set larger than the recessed portion, and the embedded body is temporarily fixed to the recessed portion in a compressed state. Manufacturing method.
The method for producing a seat pad according to any one of claims 1 to 4, wherein the seat pad main body and the embedding body are polyurethane foam.
The method for manufacturing a seat pad according to any one of claims 1 to 5, wherein the buried portion of the buried body is the back surface of the lower end of the seat pad body.
The method for manufacturing a seat pad according to any one of claims 1 to 6, wherein the recess has a shape along the upper surface shape of the embedded body.