JPH0612690Y2 - Vehicle seat - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a vehicle seat, and more particularly to a soft-hard two-layer structure seat.

[Prior Art] Conventionally, vehicle seats have been studied from the viewpoint of ergonomics, and comfortable seats have been studied from various directions. As a result, it has become clear that it is necessary to consider static characteristics (size of seat, final stable posture, body pressure distribution, etc.) and dynamic characteristics against vibration and acceleration during running. Conventional sheets have been manufactured by comprehensively considering these factors.

[Problems to be solved by the invention] By the way, the body pressure distribution among the static characteristics mentioned above refers to the pressure distribution on the contact surface between the human body and the seat, but in order to be an ideal seat, It is necessary that the body pressure in the case of ideal distribution be adapted to the distribution and capable of receiving a load. However, it cannot be said that the conventional sheet is formed correspondingly to the ideal body pressure distribution, and from this viewpoint, a sufficient sheet has not yet been developed.

Further, the seat needs to have a seat surface shape so that a final stable posture (finally stable posture when properly seated) can be obtained in a seated state. But,
The amount of subsidence of the seat surface is different in proportion to the above body pressure distribution. For example, the amount of subsidence is large at the ischial tuberosity and the like, and conversely, the amount of subsidence is small on the side of the thigh. Therefore, when determining the seat surface shape in the unloaded state (non-seated state), the design must be made in consideration of the distribution of such changes in the depression, which is extremely difficult.

In view of these problems of the related art, the present invention aims to provide a vehicular seat that realizes a comfortable sitting comfort and that can easily set the seat surface shape by finely responding to the seat pressure distribution.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a seat cushion or a cushion pad in a seat back,
In a vehicle seat having a two-layer structure of a soft layer on the front side and a hard layer on the inner side, an ideal body pressure distribution for the seat cushion or the seat back is obtained by determining the ratio of the thickness of the hard layer in the cushion pad. It is configured to increase or decrease in proportion to the isobaric line.

[Effect] According to the present invention, a hard layer is thickly formed in a portion corresponding to a place where body pressure is high, such as an ischial tuberosity, and conversely, a portion corresponding to a place where body pressure is low, such as a thigh side. The hard layer has a surface shape proportional to the isobar of the body pressure distribution. Therefore, the seat can receive an ideal pressure corresponding to the body pressure distribution applied thereto.

Embodiments Embodiments embodying the present invention will be described in detail below with reference to the drawings.

The example shown in each drawing is an example in which the present invention is applied to a seat cushion 1 in an automobile seat.

As shown in FIGS. 3 and 4, the seat cushion 1 has a cushion pad 2 having a hard two-layer structure, and a soft layer 2a is arranged on the front surface side and a hard layer 2b is arranged on the seat frame side (not shown). It has been done. Both layers 2
The a and 2b are integrally molded with a commonly used urethane foam, separately molded into a predetermined shape, and then bonded by bonding with an adhesive.

For the cushion pad 2, it is possible to use a resin foam other than urethane, a mat-like cushion body in which natural / synthetic fibers are bound with a resin, or a combination thereof. As for the method of laminating both the hard and soft layers 2a and 2b, one may be molded first, this may be set in a molding die, and the other may be molded as it is.

Now, FIG. 1 shows the isobars according to the ideal seat pressure distribution in the seat cushion 1. According to this, as shown by the arrow A in the figure, the pressure center of the seat cushion 1 is located at a site corresponding to the ischial tuberosity that can withstand a strong pressure. That is, the left and right positions of the central portion of the seating main portion 1a are the pressure centers. Then, the seat pressure decreases toward both side holders 1b side with these two points as vertices, and also decreases toward the front part of the seating main portion 1a as indicated by arrow B in the figure. This is a part corresponding to the thigh lateral surface that cannot withstand strong pressure.

In this example, the surface shape is formed so that the hard layer 2b of the cushion pad 2 has a protrusion amount proportional to the seat pressure isobaric line shown in FIG. That is, as shown in FIG. 2 and FIG. 3, the hard layer 2b is formed at the most protruding position at the above-mentioned two locations corresponding to the ischial tuberosity, and the height is continuously reduced from this point to the seating main portion 1a. In the part corresponding to the thigh lateral surface in, the front part is inclined upward and becomes thinner as it goes forward.

On the other hand, the soft layer 2a has a thickness distribution opposite to that of the hard layer 2b, so that the amount of depression in the seating main portion 1a is made uniform over the entire area. Then, the surface shape of the seat cushion is set so as to obtain the above-mentioned curve of the final stable posture when the seat cushion is depressed. By setting in this way, the seat surface shape when not seated can be easily set by adding a predetermined amount of depression to the seat surface shape.

The seat cushion 1 of this example is configured as described above, and since the thickness of the hard layer 2b is changed in proportion to the isobar of the ideal seat pressure distribution, a large seat pressure such as that of the ischial tubercle is obtained. The seat-side receiving pressure is high in the area where the pressure is applied, and conversely, the receiving pressure is low in areas such as the thigh side where only a small seat pressure acts. Therefore, an ideal pressure distribution can be obtained over the entire seat cushion 1.

Further, since the thickness ratio of the soft and hard layers 2a and 2b is also increased / decreased in proportion to the seat pressure distribution, the amount of depression at the time of sitting can be made substantially uniform. Therefore, the change in the seat surface shape before and after seating is small, and therefore the seat surface shape before seating may be set according to the final stable posture curve in the seated state, which facilitates the design.

Further, even when the seat pressure is high, the subsidence is restricted by the hard layer 2b, and the total amount of the subsidence is small. Therefore, there is a margin in the cushion stroke, and the dynamic characteristics with respect to vibration during traveling are improved. The riding comfort is improved.

Although the seat cushion is shown and described in this example, it may be applied to a seat back.

[Effects of the Invention] The effects of the present invention are as follows.

Since the body pressure distribution can be adjusted to an ideal state, the sitting comfort of the seat is significantly improved.

Since the surface shape of the seat before and after seating is made uniform over the entire area, it becomes easy to design the seat surface shape in the free state.

Since the cushion stroke has a margin, it also has excellent dynamic characteristics, and from this aspect it can be expected to improve riding comfort.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a seat pressure distribution curve, FIG. 2 is a perspective view showing a seat cushion, and FIG. 3 is III-I in FIG.
A sectional view taken along the line II and FIG. 4 are sectional views taken along the line IV-IV. 1 ... Seat cushion 2a ... Soft layer 2b ... Hard layer

Claims (1)

[Scope of utility model registration request] 1. A vehicle seat in which a cushion pad in a seat cushion or a seat back has a two-layer structure of a soft layer on the front surface side and a hard layer on the inner side. A vehicle seat, wherein a ratio is increased or decreased in proportion to an isobar of an ideal body pressure distribution for the seat cushion or the seat back.