JPH11348629A - Urethane pad for seat - Google Patents

Abstract

(57) [Summary] [Problem] To provide a urethane pad for a sheet capable of improving both the softness of the pad surface and the springiness and vibration isolation of the seat, even if the same urethane compounding formulation is used. thing. SOLUTION: A vertical and horizontal slit 12 having a predetermined depth is provided in the center (main part) surface of a seat part of a polyurethane foam seat pad material 11. The slit 12 is formed by making a cut on the surface with a blade after the urethane pad foaming, or by providing a slit in the foaming mold itself.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a urethane pad for a sheet.

[0002]

2. Description of the Related Art As a conventional urethane pad for a sheet, a spring body is generally attached below a pad. However, such a urethane pad is not provided with a separate spring body, and is directly provided on a metal panel. The structure of the placing is also used.

[0003]

However, such a conventional urethane pad for a sheet has the following problems. (1) In order to change the spring feeling and the improvement in vibration isolation without changing the characteristics of a metal spring or the like, it is common to change the urethane compounding formula or density to form urethane pads having different characteristics. For this reason, it is necessary to prepare many urethane compounding formulations in order to meet many requirements. (2) When the pad hardness is increased to improve the feeling of spring, the softness felt when the pad surface is pressed by hand or at the beginning of sitting (hereinafter referred to as the soft feeling of the pad surface) is lost. It is difficult to satisfy the characteristics.

The present invention has been made in view of such a conventional problem. Even when the same urethane compounding formulation is used, the soft feeling of the pad surface is improved, and the feeling of spring and vibration isolation of the seat are improved. An object of the present invention is to provide a urethane pad for a sheet that can be improved and improved.

[0005]

According to the first aspect of the present invention, there is provided a polyurethane foam seat pad having a pad surface less than 100 mm in contact with an occupant. A plurality of slits are provided at intervals.

According to a second aspect of the present invention, in the polyurethane foam seat pad, an in-plane compressive stress is generated on the pad surface in contact with an occupant when no load is applied. Things.

According to a third aspect of the present invention, in the urethane pad for a sheet according to the second aspect, the compressive stress in the in-plane direction is such that the auxiliary material embedded in the pad surface is moved in the in-plane direction. The forcible displacement is caused by the forced displacement.

According to a fourth aspect of the present invention, in the urethane pad for a sheet according to the second aspect, the compressive stress in the in-plane direction is such that the urethane pad has a width or a length larger than that of the urethane pad. This is characterized in that it is generated by setting a short frame.

According to a fifth aspect of the present invention, in the urethane pad for a sheet according to the second aspect of the present invention, the compressive stress in the in-plane direction is reduced by connecting the urethane pad formed in a convex shape in advance to the frame. When the pad is set inside, the back surface of the pad is pulled toward the frame, and the AS
This is characterized in that it is generated by forming the SY shape.

According to a sixth aspect of the present invention, in the urethane sheet for a sheet according to the fifth aspect of the present invention, the pad back surface is pulled toward the frame, and the pad back surface and the frame receiving the pad are also provided. Preferably, the spring body attached to the frame is adhered.

According to a seventh aspect of the present invention, in the urethane sheet for a sheet according to the fifth aspect, the auxiliary material embedded in the back surface of the pad is used as a method of pulling the back surface of the pad toward the frame. And the frame for receiving the pad or the spring body attached to the frame.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the urethane pad for a sheet according to the present invention will be described below in detail with reference to the accompanying drawings. (First Embodiment) FIGS. 1 to 5 show a urethane pad for a sheet according to a first embodiment of the present invention.
FIG. 1 is a diagram showing the configuration of the first embodiment, in which (a)
Is a plan view, (b) is a sectional view taken along line AA in (a),
(C) is a BB sectional view in (a). FIG. 2 is a stress-strain diagram of a general flexible polyurethane foam, FIG. 3 is an explanatory diagram of an operation, and FIG. 4 is a diagram showing a deflection characteristic under partial load and results of sensory evaluation in the first embodiment.
FIG. 5 is a load-deflection diagram of the load applied by the φ200 disk loader in the first embodiment.

First, the structure will be described. As shown in FIG. 1, a urethane pad for a seat according to the first embodiment is provided on a surface (center portion) of a seat portion of a polyurethane foam seat pad material 11 at a predetermined position. Vertical and horizontal slits 12 having a depth are provided. The slit 12 can be formed by making a cut on the surface with a blade after the urethane pad foaming, or by providing a slit in the foaming mold itself.

Next, the operation of the first embodiment will be described. When a load element smaller than the area is pushed into the surface of the urethane pad material, the pad material is compressed in the direction in which the load element is pushed in, and a reaction force is generated. In the near portion, the material is stretched, and a tensile force is generated to push back the load element.

FIG. 2 shows a stress-strain diagram of a general flexible polyurethane foam. The longitudinal modulus of elasticity in the tensile direction is 10 in the case of the compressive direction near the strain of 0.1 to 0.5.
Since it is about twice as large, the rigidity of the surface becomes large. This is remarkable when a part of a wide pad surface is pressed, and when the width of the load element and the pad surface does not change so much, the influence as the surface rigidity is small.

In the case of the first embodiment, since the slit 12 is provided on the surface of the pad material 11, a tensile force generated on the surface of the pad material around the load element does not occur beyond the slit at a position shallower than the slit. Therefore, the reaction force generated in the load element is weaker than when there is no slit (see FIG. 3). For this reason, an excellent "soft feeling on the pad surface" can be obtained in a state where a partial load is applied, for example, when the pad surface is pressed by hand or the vicinity of the ischial tubercle contacts partially at the beginning of the sitting operation.

On the other hand, when a load is applied to a wide area that is full of the main portion of the pad, such as when the occupant is completely seated, the effect of the decrease in surface rigidity does not appear, and the same flexural characteristics as when there is no slit. Is shown. Also, even when a load is applied to an area slightly smaller than the area of the main part, the slit of the pad material is provided only to a certain depth from the surface, so when the displacement amount increases, it will be similar to a normal pad material. A tensile force is also generated, so that the pads other than those directly under the load element also bear the load.

As described above, even if the slits 12 are provided on the surface of the pad material 11, the feeling of resilience in the seated state, the total amount of deflection, the characteristics with the bottom, etc. can be made equal to those without the slits. It is possible to achieve both the softness of the surface and the characteristics such as the total amount of deflection.

FIG. 4 shows the results of a soft sensory evaluation of the pad surface using a method of estimating the amount of deflection and the magnitude under a load of 60 N with a φ50 mm loader having a small load area with and without a slit, and FIG. Wide φ200mm
2 shows a load-deflection curve by the load element of FIG.

The provision of the slits increases the amount of deflection when the load area is small and increases the soft feeling, while the data shows that there is no change in the characteristics when a load is applied over a wide area. I understand.

When the interval between the slits is 100 mm, there is no change in the soft feeling on the pad surface.
Setting it to mm improved the softness of the surface. Therefore, it is understood that the slit interval needs to be less than 100 mm.

On the other hand, the depth of the slit is 5 mm to 10 m.
m increases the softness of the surface, but if this slit penetrates to the back of the pad, that is, if the urethane pad blocks become completely independent, only the part that touches the occupant's body when sitting As a result, the deflection characteristics with respect to the load are changed as compared with the case where the pad is integrated, and the original purpose cannot be achieved.

A structure in which a slit is provided on the pad surface is also found in a wire pulling portion for drawing in the skin as disclosed in, for example, Japanese Patent Application Laid-Open No. 9-37886. Since the interval is too wide, it does not contribute to improving the soft feeling of the pad surface.

(Second Embodiment) FIGS. 6A and 6B are views showing a urethane pad for a sheet according to a second embodiment of the present invention, wherein FIG. 6A is a plan view and FIG. A-
It is A sectional drawing. In the second embodiment, in the polyurethane foam seat pad material 21, both ends of two left and right pull wires 23 embedded inside the pad material on both sides of the seat main portion for attaching the seat skin are formed in a string shape. (Preload cable) 24 to draw and fix to the center of the seat main part.

As a result, since a compressive stress in the left-right direction is generated on the surface of the pad material 21, even if the seat surface is partially pressed, a tensile force is hardly generated on the surface of the pad material 21 and the soft feeling of the pad surface is improved. However, when a load is applied over a wide area, the same characteristics as those when there is no initial compressive stress in the left-right direction are obtained.

(Third Embodiment) FIGS. 7 and 8 show a urethane pad for a sheet according to a third embodiment of the present invention. FIGS. 7A and 7B are diagrams showing the configuration of the third embodiment, in which FIG. 7A is a plan view, and FIG.
It is sectional drawing. FIG. 8 is a diagram for explaining an assembling method according to the third embodiment.

In the third embodiment, the width of the cushion pan supporting the pad material 31 is set to be smaller than the width of the upper portion of the pad material 31, and as shown in FIG. By pressing and setting the pad material 31 into the pad 35, a compressive stress in the lateral direction is generated on the surface of the pad material 31, thereby improving the soft feeling of the pad surface.

(Fourth Embodiment) FIGS. 9 to 10 are views showing a urethane pad for a sheet according to a fourth embodiment of the present invention. FIGS. 9A and 9B are diagrams showing a configuration of the fourth embodiment, wherein FIG. 9A is a plan view, and FIG.
FIG. 3B is a cross-sectional view, and FIG. 3C is a cross-sectional view along AA in FIG. FIG. 10 is a diagram for explaining an assembling method according to the fourth embodiment.

In the fourth embodiment, as shown in FIG.
The pad material 41 whose front and back surfaces are formed into a curved surface so that the central portion has a convex shape is connected to the cushion pan frame 45 using a pull wire 46 provided on the back surface as shown in FIG. By bonding the back surface of the pad material 41 and the cushion pan frame 45 to form a normal ASSY shape with a flat surface, an initial compressive load in the lateral direction is generated on the surface of the pad material 41, and the soft feeling of the pad surface is reduced. It is to improve. Also, in the case of a sheet having a metal spring under the pad material, by connecting the metal material spring to the back surface of the pad material, a normal ASS
A Y-shape is also possible.

As a prior art, Japanese Patent Application Laid-Open No. 8-989
There is a convex pad material as disclosed in Japanese Patent Publication No. 66-66. However, if the pull wire near the pad surface or the pull wire of the skin material is pulled as in this prior art,
Since the initial compressive stress in the vertical direction is generated and the soft feeling of the pad surface as the object of the present invention cannot be obtained, by pulling the pad back surface or its vicinity as in the fourth embodiment. It is necessary to generate an initial compressive load in the lateral direction.

[0031]

According to the present invention, since the present invention has the above-mentioned characteristics, even if the same urethane compounding formulation is used,
The effect of improving the softness of the pad surface and improving the springiness and vibration isolation of the seat can be achieved. In the present invention, the cushion pad has been mainly described, but the present invention can be easily applied to other pads such as a back pad and a headrest pad.

[Brief description of the drawings]

FIG. 1 is a view showing a configuration of a urethane pad for a sheet according to a first embodiment of the present invention, wherein (a) is a plan view,
(B) is an AA sectional view in (a), (c) is (a)
It is BB sectional drawing in.

FIG. 2 is a stress-strain diagram of a general flexible polyurethane foam.

FIG. 3 is a diagram for explaining the operation of the first embodiment.

FIG. 4 is a diagram showing a deflection characteristic under a partial load and results of a sensory evaluation in the first embodiment.

FIG. 5 is a load-deflection diagram of a φ200 disk loader according to the first embodiment.

FIG. 6 is a diagram showing a configuration of a second embodiment,
(A) is a top view, (b) is an AA sectional view in (a).

FIG. 7 is a diagram showing a configuration of a third embodiment,
(A) is a top view, (b) is an AA sectional view in (a).

FIG. 8 is a view for explaining an assembling method according to a third embodiment;

FIG. 9 is a diagram showing a configuration of a fourth embodiment,
(A) is a plan view, (b) is a BB sectional view in (a), and (c) is an AA sectional view in (a).

FIG. 10 is a view for explaining an assembling method according to a fourth embodiment;

[Explanation of symbols]

 11, 21, 31, 41 Urethane pad material 12 Slit 23 Skin pull wire 24 Preload cable 35, 45 Cushion pan frame 46 Pad back wire

Claims (7)

[Claims] 1. A urethane pad for a seat, wherein a plurality of slits are provided at intervals of less than 100 mm on a surface of a pad made of a polyurethane foam, which is in contact with an occupant. 2. A urethane pad for a seat, wherein a compressive stress in an in-plane direction is generated on a pad surface in contact with an occupant when no load is applied, in a polyurethane foam seat pad. 3. The urethane pad for a sheet according to claim 2, wherein the in-plane compressive stress is generated by forcibly displacing a sub-material embedded in the pad surface in the in-plane direction. Urethane pad for seats characterized by the following. 4. The urethane pad for a sheet according to claim 2, wherein the in-plane compressive stress is generated by setting the urethane pad on a frame having a shorter width or length. A urethane pad for a sheet, comprising: 5. The urethane pad for a sheet according to claim 2, wherein the compressive stress in the in-plane direction is such that when the urethane pad formed in a convex shape in advance is set in the frame, the back surface of the pad is formed. A urethane pad for a sheet, which is generated by being pulled toward the frame side to form an ASSY shape with a flat surface. 6. The urethane sheet for a sheet according to claim 5, wherein a method of pulling the back surface of the pad toward the frame is performed by:
A urethane pad for a sheet, wherein the back surface of the pad is adhered to the frame receiving the pad or a spring body attached to the frame. 7. The urethane pad for a sheet according to claim 5, wherein the back surface of the pad is pulled toward the frame.
A urethane pad for a sheet, wherein the auxiliary material embedded in the back surface of the pad is connected to the frame for receiving the pad or the spring body attached to the frame.