JP5424398B2 - Seat structure - Google Patents

Description

  The present invention relates to a seat structure, and more particularly, to a seat structure suitable as a seat for a transportation device such as an automobile, an aircraft, and a train.

  For example, in a seat structure for an automobile, the upper body of a seated person is positioned rearward relative to the seat back as a mechanism for reducing neck damage (whipping) due to a sudden backward tilt of the head during a rear-end collision. A so-called active headrest mechanism is known that uses a moving force to move the headrest forward and upward to quickly support the neck. For example, in Patent Documents 1 and 2, a pressure receiving member is provided near the lower portion of the headrest, and when the pressure receiving member is pressed by receiving a force from a seated person at the time of a collision, the headrest moves relatively forward. It has become.

  However, the basic structure shown in Patent Documents 1 and 2 is that a back frame is provided with an S-shaped spring, and a cushion material such as a urethane material is supported by the S-shaped spring. Therefore, in the case of an active headrest mechanism, it is necessary to provide the pressure receiving member and the like in addition to the S-shaped spring, which makes the structure complicated, increases the weight, and increases the cost.

  In view of the above points, Patent Document 3 proposes a structure in which a surface spring structure for supporting a cushion material for a seat back is coupled to a back frame using a plurality of connection wires. According to this structure, when a predetermined load or more is input to the seat back due to a rear-end collision or the like, one of the plurality of connecting wires is disconnected, so that the amount of movement of the face spring structure to the rear increases, thereby Even when the headrest is fixed, the time until the head contacts the headrest is shortened.

JP-A-11-268565 JP 2001-58533 A JP 2009-107571 A JP 2003-182427 A

  According to Patent Document 3, the structure is simplified compared to Patent Documents 1 and 2 in that a special mechanism for moving the headrest forward is not required. However, Patent Document 3 also discloses that a surface spring structure for supporting a cushion material such as a urethane material is required, and that the structure is complicated and the structure is heavy in the first place. It is no different from the two ones. Moreover, in patent document 3, while supporting a surface spring structure, when a force beyond a predetermined | prescribed force worked, the connection wire with which a connection with a back frame is cancelled must be newly provided, and normal urethane material is used. It can be said that the frame structure is more complicated than the seat structure used as a cushioning material.

  On the other hand, in order to reduce the weight of the seat structure, the present applicant has conventionally proposed a seat structure in which a tension structure provided with a three-dimensional solid knitted fabric or a two-dimensional net material on a back frame is used as a cushion material. (See Patent Document 4). In Patent Document 4, when a predetermined load or more is applied to the cushion material stretched on the back frame due to a rear-end collision or the like, the side frame falls down, thereby reducing the tension of the cushion material and effectively applying the impact. It has a structure that can be attenuated. According to this, since it is not necessary to provide the face spring structure as in Patent Documents 1 to 3, the impact can be attenuated by receiving the human body with a simple configuration. In addition, there is an energy absorption effect due to the inward deformation of the side frame.

  In order to attenuate the impact more effectively by receiving a load greater than a predetermined value at the time of the rear-end collision, it is desirable to cause the human body to intrude more quickly in a range surrounded by the back frame. Thereby, even if the headrest does not move forward, the head is supported by the headrest more quickly. However, in the back frame shown in Patent Document 4, the side frame, the lower frame, and the upper frame are integrated by welding or caulking. The cushion material provided as a tension structure moves relative to the depth direction when a load is applied, and at the same time, the frame deforms, and the cushion material attenuates the impact while receiving the human body again. In order to achieve this, it is desirable to provide a mechanism that serves as a trigger that facilitates deformation of the frame during the rear-end collision.

  Patent Document 4 is a dummy model ("" BioRID-II ", weight approximately 78 kg, spinal column structure: 7 cervical vertebrae, 12 thoracic vertebrae, 5 lumbar vertebrae) corresponding to a 50% tile of an American adult male. In some cases, the lateral frame portion constituting the upper frame is arranged at a position corresponding to the vicinity of the shoulder ridge, but not only that, but also at a position below the lateral frame portion and corresponding to the vicinity of the chest. A reinforcing frame is provided which extends in the lateral direction. For this reason, when the human body is pressed against the seat back during a rear-end collision, the human body comes into contact with the reinforcement frame, preventing relative movement in the depth direction of the back frame, and also causing a difficulty in causing deformation of each frame. It was.

  The present invention has been made in view of the above, and is a seat structure including a seat back provided with a cushion material stretched on a back frame, and when a predetermined load or more is input to the seat back, Provided is a seat structure capable of promptly deforming, reducing the tension of a cushioning material, moving a human body relatively quickly in the depth direction of a back frame, and performing head support by a headrest more quickly than before. This is the issue.

  In order to solve the above problems, the seat structure of the present invention is a seat structure in which a cushion material is stretched on a back frame, and the back frame has a plate-like member having a predetermined width and length. The plate-like member is provided with a pair of side frames provided so that the width direction thereof is substantially along the front-rear direction, and each end is connected to each front edge upper end of the pair of side frames. A first upper frame; a second upper frame provided with each end connected to upper ends of the rear edges of the pair of side frames; and a lower frame connecting the lower ends of the pair of side frames. A headrest support portion that is bent upward is formed in either the first upper frame or the second upper frame, and in the vicinity of the base end portion of the headrest support portion, the first The upper frame and the second upper frame are connected to each other by a connecting member having an elastic member, and between the pair of side frames and from the connecting position by the elastic member in the vicinity of the base end portion of the headrest support portion. The frame is not arranged until the frame, and is characterized by an indentation space in which the back of the occupant is indented together with the cushion material when subjected to a predetermined impact or more.

The seat structure of the present invention is a seat structure in which a cushion material is stretched on a back frame, and the back frame is formed of a plate-like member having a predetermined width and length, A pair of side frames provided so that the width direction of the plate member is substantially along the front-rear direction, and a first upper frame provided by connecting each end to the upper end of each front edge of the pair of side frames; Each of the pair of side frames includes a second upper frame that is connected to each upper end of each rear edge, and a lower frame that connects the lower ends of the pair of side frames. Either one of the upper frame and the second upper frame is formed with a headrest support portion that is bent upward, and in the vicinity of a base end portion of the headrest support portion, the first upper frame and 2 The upper frames are connected to each other, and at this connection position, at least one of the first upper frame and the second upper frame has a portion having a different rigidity in the same cross section, and between the pair of side frames. In addition, no frame is arranged between the connection position in the vicinity of the base end portion of the headrest support portion and the lower frame, and the occupant's back is indented together with the cushion material when an impact of a predetermined level or more is applied. It is characterized by an intrusive space.

  The first upper frame includes a horizontal frame portion extending substantially horizontally, and a vertical frame extending downward from each end portion of the horizontal frame portion and coupled to each front edge upper end portion of the pair of side frames. A headrest support portion bent in a substantially inverted U shape at a substantially central portion of the lateral frame portion, and the second upper frame is a lateral frame extending substantially horizontally. And a vertical frame portion that extends downward from each end portion of the lateral frame portion and is connected to each upper end portion of the rear edges of the pair of side frames, and in the first upper frame, It is preferable that a portion of the lateral frame portion adjacent to the base end portion of the headrest support portion is connected to the lateral frame portion of the second upper frame.

  The distance between the pair of side frames is at least 350 mm at the narrowest portion, and the narrower distance between the vertical frame parts in the first upper frame and the vertical frame parts in the second upper frame is the smallest. The narrowest portion is at least 300 mm, and the lower frame includes a horizontal frame portion positioned below one of the horizontal frame portion of the first upper frame and the horizontal frame portion of the second upper frame, and the lower frame. The spacing is preferably at least 500 mm.

  It is preferable that portions having different rigidity in the same cross section set in at least one of the first upper frame and the second upper frame are set by changing heat treatment conditions.

  Further, the first upper frame and the second upper frame are welded, and the welded portion is a portion having low rigidity in the same cross section set in at least one of the first upper frame and the second upper frame. It is preferable that

The seat structure of the present invention is a seat structure in which a cushion material is stretched on a back frame, and the back frame is formed of a plate-like member having a predetermined width and length, A pair of side frames provided so that the width direction of the plate member is substantially along the front-rear direction, and a first upper frame provided by connecting each end to the upper end of each front edge of the pair of side frames; Each of the pair of side frames includes a second upper frame that is connected to each upper end of each rear edge, and a lower frame that connects the lower ends of the pair of side frames. The upper frame includes a horizontal frame portion that extends substantially horizontally, and a vertical frame portion that extends downward from each end portion of the horizontal frame portion and is coupled to the front edge upper ends of the pair of side frames. The second upper frame includes a pair of oblique sides bent obliquely upward and inward from the upper ends of the rear edges of the side frames, respectively, and upward from the inner ends of the pair of oblique sides. A headrest support portion having a pair of substantially vertical frame portions that are bent to each other but not connected to each other, and near a base end portion of the pair of substantially vertical frame portions constituting the headrest support portion The first upper frame and the second upper frame are connected to each other by a connecting member having an elastic member.

The seat structure of the present invention is a seat structure in which a cushion material is stretched on a back frame, and the back frame is formed of a plate-like member having a predetermined width and length, A pair of side frames provided so that the width direction of the plate member is substantially along the front-rear direction, and a first upper frame provided by connecting each end to the upper end of each front edge of the pair of side frames; Each of the pair of side frames includes a second upper frame that is connected to each upper end of each rear edge, and a lower frame that connects the lower ends of the pair of side frames. The upper frame includes a horizontal frame portion that extends substantially horizontally, and a vertical frame portion that extends downward from each end portion of the horizontal frame portion and is coupled to the front edge upper ends of the pair of side frames. The second upper frame includes a pair of oblique sides bent obliquely upward and inward from the upper ends of the rear edges of the side frames, respectively, and upward from the inner ends of the pair of oblique sides. A headrest support portion having a pair of substantially vertical frame portions that are bent to each other but not connected to each other, and near a base end portion of the pair of substantially vertical frame portions constituting the headrest support portion The first upper frame and the second upper frame are connected to each other, and at this connection position, at least one of the first upper frame and the second upper frame has a portion having different rigidity in the same cross section. It is characterized by that.

  The distance between the pair of side frames is at least 350 mm at the narrowest portion, and the distance between the vertical frame portions in the first upper frame is at least 300 mm at the narrowest portion, The distance between the direction frame portion and the lower frame is preferably at least 500 mm.

  The distance between the boundary of one oblique side and the substantially vertical frame part and the boundary of the other oblique side and the substantially vertical frame part in the second upper frame is set to be in a range of 160 to 190 mm. preferable.

  It comprises two pipe parts formed from synthetic resin and a connecting part spanned between the pipe parts and formed from synthetic resin or fabric, and the two pipe parts constitute the headrest support part It is preferable to have a cushioning member mounting member for a headrest that is fitted and disposed in the substantially vertical frame portion.

  It is preferable that portions having different rigidity in the same cross section set in at least one of the first upper frame and the second upper frame are set by changing heat treatment conditions.

  Further, the first upper frame and the second upper frame are welded, and the welded portion is a portion having low rigidity in the same cross section set in at least one of the first upper frame and the second upper frame. It is preferable that

  According to the present invention, in the vicinity of the base end portion of the headrest support portion, the first upper frame and the second upper frame are connected to each other by the connecting member provided with the elastic member. For this reason, at the time of rear-end collision, when a force greater than a predetermined force is applied in the direction of pushing in the cushion material stretched on the seat back, the first upper frame and the second upper frame are connected via an elastic member. As a result, the connecting force between the first upper frame and the second upper frame is quickly reduced. When the coupling force between the first upper frame and the second upper frame is reduced, the force for supporting the load is also reduced, so that the inwardly-turning deformation of the side frame caused by the pressing of the cushion material is performed more quickly. As a result, since the human body can move backward more quickly, the time until the head comes into contact with the headrest is shortened, the headrest is quickly supported by the headrest, and neck damage (whipping) is reduced. be able to. In addition, according to the present invention, it is not necessary to use a face spring structure to elastically support the cushion material, so that the structure is simpler and an extremely lightweight seat structure can be manufactured.

  Further, at least one of the first upper frame and the second upper frame may have a portion having different rigidity in the same cross section at the connection position of the first upper frame and the second upper frame. Also in this case, when an impact is input, it is easy to bend because there is a difference in rigidity, and a portion having low rigidity in the same cross section, that is, a portion having a low yield point and a large elongation is likely to be deformed. The connection between the two is easily released, and the same effect as described above is produced.

  The present invention is also configured such that the frame is not disposed between the connection position in the vicinity of the base end portion of the headrest support portion and the lower frame, so that the human body (back) can receive a shock when receiving a predetermined impact or more. Can be easily invaded with the cushioning material. That is, if there is any reinforcement frame at a position corresponding to the vicinity of the chest of the occupant, the reinforcement frame prevents the upper body from invading, and it takes more time for the head to contact the headrest. End up. Therefore, in this way, the connection position by the elastic member in the vicinity of the proximal end portion of the headrest support portion (that is, a dummy model (“BioRID-II” corresponding to a 50% American adult male tile, weight of about 78 kg, spine structure: cervical spine) It is preferable that there is a large indentation space where no reinforcing frame exists from the position corresponding to the vicinity of the shoulder ridges of 7 pieces, 12 thoracic vertebrae, and 5 lumbar vertebrae) to the lower frame.

  In addition, the second upper frame includes a pair of oblique sides bent obliquely upward and inward from the respective rear edge upper end portions of the side frames, and is bent upward from the inner ends of the pair of oblique sides. On the other hand, it can also be set as the structure which has a headrest support part which has a pair of substantially vertical frame part which is not mutually connected. In this case, the hypotenuse part exists at a position corresponding to the vicinity of the chest of the human body, but since the substantially vertical frame parts constituting the headrest support part are not connected to each other, the rigidity is low and the human body is invaded. However, even if it comes into contact with this hypotenuse, a large reaction force that rebounds the human body does not occur. However, when a force that pushes the oblique side portion is applied, the portion of the connecting member via the elastic member serves as a fulcrum, and the substantially vertical frame portion moves forward and approaches the head. As a result, as in the above-described aspect, the human body is pushed in quickly, and the head is quickly brought into contact with the headrest, so that neck damage can be reduced more effectively. In this case, the oblique side portion of the second upper frame constituting a part of the back frame functions as a point of action, and is composed of a member separate from the member constituting the back frame like the conventional active headrest mechanism. Since the pressure receiving member is not provided, the structure is simple and can contribute to weight reduction.

FIG. 1 is a perspective view illustrating a frame of a seat structure according to a first embodiment of the present invention as viewed from the front side. FIG. 2 is a perspective view showing the frame of the seat structure according to the first embodiment as seen from the back side. FIG. 3A is a front view showing the frame of the seat structure according to the first embodiment, and FIG. 3B is a right side view showing the frame of the seat structure according to the first embodiment. FIG. 3C is a rear view showing the frame of the seat structure according to the first embodiment. 4A is a plan view showing a part of the frame of the seat structure according to the first embodiment, and FIG. 4B is a front view thereof, for explaining the connecting member. FIG. 4C is a cross-sectional view taken along the line BB in FIG. 4B, and FIG. 4D is a diagram illustrating the relationship between the elastic member constituting the connecting member and the metal fitting. FIG. 5 is a rear view of a state in which a dummy model is seated on the frame of the seat structure according to the first embodiment. FIG. 6 is a side view of a state in which a dummy model is seated on the frame of the seat structure according to the first embodiment. FIG. 7 is a view for explaining a mode in which a rubber string member is hung around the boundary between the headrest forming portion and the back cushion portion, (a) is a view showing an appearance, and (b) is (a) (C) is a figure which shows the state before pulling a rubber string member, (d) is a figure which shows the state which pulled the rubber string member. FIG. 8 is a view for explaining the appearance of a state in which a rubber string member is hung around the boundary between the headrest forming portion and the back cushion portion, and (a) shows a state before the rubber string member is pulled. It is a figure, (b) is a figure which shows the state which pulled the rubber string member. FIG. 9 is a perspective view of the seat structure frame according to the second embodiment of the present invention as seen from the front side. FIG. 10 is a front view showing a frame of a seat structure according to the second embodiment of the present invention. Fig.11 (a) is the side view which showed the principal part of the flame | frame of the seat structure based on the 2nd Embodiment of this invention, FIG.11 (b) is a front view. FIG. 12 is a rear view of a state in which a dummy model is seated on the frame of the seat structure according to the second embodiment. FIG. 13 is a diagram for explaining a configuration of a headrest according to the second embodiment. FIG. 14: is the perspective view seen from the front side which showed the flame | frame of the seat structure which concerns on the 3rd Embodiment of this invention. Fig.15 (a) is the front view which showed the frame of the seat structure based on the 3rd Embodiment of this invention, FIG.15 (b) is the BB sectional drawing of Fig.15 (a). FIG. 16 is an exploded view showing the first and second upper frames, the headrest support portion, the connecting member and the like in the seat structure according to the third embodiment of the present invention. FIG. 17 is a diagram for explaining the operation of the seat structure according to the third embodiment of the present invention. FIG. 18: is the perspective view seen from the front side which showed the flame | frame of the seat structure which concerns on the 4th Embodiment of this invention. FIG. 19A is a front view showing a frame of a seat structure according to the fourth embodiment of the present invention, and FIG. 19B is a cross-sectional view taken along line AA of FIG. FIG. 20 is an exploded view showing the first and second upper frames, the headrest support portion, the connecting member and the like in the seat structure according to the fourth embodiment of the present invention. FIG. 21 is a diagram for explaining the operation of the seat structure according to the fourth embodiment of the present invention. FIG. 22 is a perspective view showing an essential part of an application example of the seat structure according to the fourth embodiment of the present invention. FIG. 23 is a front view showing a frame of a seat structure of a comparative example used in the experiment. FIG. 24 (a) shows a schematic diagram when the pipe material is heated by a heating jig, and FIG. 24 (b) shows the pipe material feed temperature, current, water flow rate, and arrival at the time of heating. It is the figure which showed the result measured by changing various settings, such as temperature.

  Hereinafter, the present invention will be described in more detail based on the embodiments shown in the drawings. First, based on FIGS. 1-8, the seat structure 1 for motor vehicles based on the 1st Embodiment of this invention is demonstrated. As shown in these drawings, the seat structure 1 according to this embodiment includes a cushion frame 10 constituting a seat cushion and a back frame 20 constituting a seat back.

  The cushion frame 10 includes a pair of side frames 11 and 12 arranged at a predetermined interval, and a front edge frame 13 arranged on the front edge side of the side frames 11 and 12.

  The back frame 20 includes a pair of side frames 21 and 22 disposed at a predetermined interval, a first upper frame 23 and a second upper frame 24 disposed between the upper portions of the side frames 21 and 22, and the side frames And a lower frame 25 disposed between the lower portions of the frames 21 and 22. And the lower part of the side frames 21 and 22 of the back frame 20 is connected to the rear part of the side frames 11 and 12 of the cushion frame 10 via the reclining adjuster 40, and the back frame 20 can tilt back and forth with respect to the cushion frame 10. Provided.

  Each of the side frames 21 and 22 of the back frame 20 is formed of a plate-like member having a predetermined width, and the width direction thereof is arranged in a direction substantially along the front-rear direction. More precisely, the side frames 21 and 22 are not parallel to each other, and are arranged in such a direction that the front edge side opens slightly outward from the rear edge side (see FIG. 3A). As shown in FIG. 3B, when viewed from the side, the front edge side has a bulge that bulges forward, but the rear edge side has a substantially straight shape.

  The first upper frame 23 is connected to the horizontal frame portion 23a extending substantially horizontally and the upper ends of the front edges of the pair of side frames 21 and 22 extending downward from the ends of the horizontal frame portion 23a. And a vertical frame portion 23b. And the headrest support part 23c bent by the substantially reverse U shape is integrally formed in the approximate center part of the horizontal direction frame part 23a. Accordingly, there are two lateral frame portions 23a of the first upper frame 23 with the headrest support portion 23c interposed therebetween.

  The second upper frame 24 is connected to the lateral frame portion 24a extending substantially horizontally and the rear edge upper end portions of the pair of side frames 21 and 22 extending downward from the respective end portions of the lateral frame portion 24a. And a vertical frame portion 24b.

  As shown in FIGS. 4A to 4D, the two horizontal frame portions 23a of the first upper frame 23 and the horizontal frame portion 24a of the second upper frame 24 are made of a metal fitting 26a and rubber or synthetic material. It is connected by a connecting member 26 provided with an elastic member 26b made of resin. That is, the horizontal frame portion 24a of the second upper frame 24 is placed along the horizontal frame portion 23a located in the vicinity of the base end portion of the headrest support portion 23c in the first upper frame 23, and the metal fitting 26a is wound around them together. In this case, they are connected by caulking with elastic members 26b interposed between the lateral frame portions 23a, 24a and the metal fittings 26a.

  With such a configuration, the caulking of the metal fitting 26a is easily released due to the elasticity of the elastic member 26b when a predetermined force or more is input. That is, although the metal fitting 26a is wound around each of the lateral frame portions 23a and 24a, the overlapping portion is easier to open than the case where the elastic member 26b is not caulked. When the caulking is opened, the reaction force from the first upper frame 23 and the second upper frame 24 to the human body becomes lower than when both are united by the connecting member 26 and exceeds a predetermined value input by a rear-end collision or the like. Increases the ability to attenuate the load. The elastic member 26b also has a function of preventing noise from being generated during normal use between the two lateral frame portions 23a of the first upper frame 23 and the lateral frame portion 24a of the second upper frame 24. Fulfill.

  In addition, it is preferable that at least one of the first upper frame 23 and the second upper frame 24 is configured by a frame having a portion having different rigidity in the same cross section. For example, it is preferable to use a frame in which at least about 3/4 of the same cross section has a tensile strength exceeding 1100 MPa and the remaining about 1/4 has a tensile strength of 1100 MPa or less. A frame having such a stiffness difference is likely to bend, and a portion having a low rigidity in the same cross section, that is, a portion having a low yield point and a large elongation is more likely to be deformed and caulking is easily released. On the other hand, a highly rigid portion is difficult to deform and its deformation behavior is easy to control. Therefore, when such a rigidity difference is given, a low-rigidity part is positioned on the inner portion where the first upper frame 23 and the second upper frame 24 face each other, and a high-rigidity part is positioned on the outer side. It is preferable. In addition, in this way, it is also possible to place a portion having low rigidity on the inner side and further weld both parts partially. By welding, it is possible to give a necessary feeling of rigidity during normal use, and also helps to prevent abnormal noise.

  Here, in the present embodiment, the rear edge lower end portion of the side frames 21 and 22 is located between the side frames 21 and 22 from the connecting position of the connecting member 26 that connects the first upper frame 23 and the second upper frame 24. An intrusion space 27 in which no other frame is disposed is between the lower frame 25 spanned between them. That is, in this invagination space 27, the dummy frame (“BioRID-II” having a weight of about 78 kg is used in which each of the lateral frame portions 23a, 24a, where the connecting member 26 is disposed, corresponds to a 50% tile of an American adult male. , Spinal column structure: 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae (hereinafter referred to as “dummy model” all refer to this “BioRID-II”), which corresponds to directly below the headrest support 23c. It is provided at a position corresponding to the vicinity of the shoulder crest, and no frame is disposed below it until reaching the upper edge of the lower frame 25 (see FIG. 5). In this case, the back located below the shoulder of the human body is easy to enter the intrusion space 27 (displaced from “before the collision” to “after the collision” shown in FIG. 6). Intrusion space 2 In order to easily incline the back, the width of the indentation space 27 (interval between the side frames 21 and 22) is substantially the same as the width of the dummy model from the chest to the abdomen, but larger than that. It is preferable that

  Therefore, the distance between the side frames 21 and 22 is preferably at least 350 mm at the narrowest portion (the distance indicated by the symbol c in FIG. 3C). Further, the narrower distance between the longitudinal frame parts 23b and 23b in the first upper frame 23 and the longitudinal frame parts 24b and 24b in the second upper frame 24 located at the part corresponding to the vicinity of the shoulder ridges from the chest. (In this embodiment, since the front edge side between the side frames 21 and 22 is wider than the rear edge side, the space between the vertical frame portions 24b and 24b in the second upper frame 24 is the narrowest part (see FIG. 3 (c), which is at least 300 mm, and is either one of the lateral frame portion 23a of the first upper frame 23 and the lateral frame portion 24a of the second upper frame 24. Lateral frame portions 23a, 24a located below (in this embodiment, both are at the same position, and the connecting member 26 is at the height thereof. Is preferably set to) the spacing between the lower frame 25 intervals indicated by symbol a in (FIG. 3 (c)) is at least 500 mm.

  A cushion material 30 is stretched on the side frames 21 and 22 and the first and second upper frames 23 and 24 of the back frame 20 and provided as a tension structure. As the cushion material 30, the present applicant has disclosed a three-dimensional solid knitted fabric, a two-dimensional fabric, a three-dimensional solid knitted fabric or a two-dimensional fabric laminated with a thin urethane material disclosed in Japanese Patent Application Laid-Open No. 2003-182427. Alternatively, a laminate of a plurality of these can be used, but it is preferable to include a three-dimensional solid knitted fabric that is excellent in vibration absorption function even if it is thin.

  As shown in FIG. 7, the cushion material 30 includes a base net 31 and a skin net 32. As shown in FIG. 7B, the base net 31 and the skin net 32 are formed in a bag shape in which a portion covering the back frame 20 and a portion covering the headrest support portion 23c are stitched together. Has been. First, the base net 31 is put on the headrest 23 c and the back frame 20. Next, the skin net 32 is covered, and both are joined via the surface fastener 33. In addition, as for the skin net 32 shown in FIG. 7, the front side which contacts a person is comprised from the three-dimensional solid knitted fabric 32a, and the back side is comprised from the two-dimensional fabric 32b, and both are formed in the bag shape integrally. As shown in FIGS. 7C and 7D, a rubber string member 324 is hung and squeezed around the boundary between the headrest forming portion 322 and the back cushion portion 323 in the skin net 32. By pulling the rubber string member 324, the state shown in FIG. 8A is changed to the state shown in FIG. 8B, and the skin net 32 is in a bag shape, but the headrest forming portion 322 and the back cushion portion 323 are interposed. There is an advantage that a clear division is formed, and the headrest and the seat back portion can be seen as separate bodies in appearance.

  According to the present embodiment, when a predetermined impact or more is received by the rear-end collision, the occupant's human body is displaced in a direction in which the cushion material 30 stretched on the back frame 20 is pushed. At this time, since the frame is not disposed in the intrusion space 27 surrounded by the side frames 21 and 22, the first and second upper frames 23 and 24, and the lower frame 25, a force to push the occupant's human body is generated. When the tension of the cushion material 30 is exceeded, the cushion material 30 is supported by the cushion material 30 and is invaginated into the indentation space 27 (see FIG. 8). Further, the force for pushing the cushion material 30 is consumed as the force for releasing the caulking of the metal fitting 26a by the elasticity of the elastic member 26b constituting the connecting member 26, and the energy is absorbed. And the connection force by the connection member 26 falls, and the reaction force from the 1st upper frame 23 and the 2nd upper frame 24 to a human body becomes low. As the cushion material 30 is further pushed in, the front edge side of the side frames 21 and 22 is deformed so as to fall inward, and further absorption of energy is performed, while the human body is further invaginated into the indentation space 27, and the impact force Will be attenuated. Such a behavior occurs at the time of rear-end collision. In this embodiment, except for the cushion material 30 that supports the human body, there is no frame in the intrusion space 27, and the first and second upper portions are interposed via the elastic member 26b. Since the frames 23 and 24 are connected to each other, the structure is likely to be deformed. Therefore, the behavior described above is performed much more rapidly than in the past. As a result, although the headrest 35 supported by the headrest support portion 23c does not protrude forward, the head is quickly brought into contact with and supported by the headrest 35. Thereby, damage to the neck due to a sudden backward tilt of the head can be suppressed.

  Further, in the present embodiment, the cushion material 30 is formed in a bag shape as described above and covers the back frame 20. Accordingly, when the frame is deformed by receiving an impact, the cushion material 30 is pressed by the human body and is pushed into the intrusion space 27, and the cushion material 30 rises along the deformed frame. . For this reason, the impact energy is also absorbed by the frictional force between the cushion material 30 and the frame.

  9 to 13 are views showing a seat structure according to the second embodiment of the present invention. In the present embodiment, the arrangement form of the first upper frame 230 and the second upper frame 240 is different from that of the above embodiment, but other configurations are the same as those of the above embodiment.

  That is, the first upper frame 230 of the present embodiment includes a horizontal frame portion 230a that extends substantially horizontally, and front edges of the pair of side frames 21 and 22 that extend downward from each end portion of the horizontal frame portion 230a. It is the structure which has the vertical direction frame part 230b each connected with the upper end part. The second upper frame 240 includes a pair of oblique sides 240c that are bent obliquely upward and inward from the rear edge upper ends of the side frames 21 and 22, respectively, and upward from the inner ends of the pair of oblique sides 240c. The headrest supporting portion 240e has a pair of substantially vertical frame portions 240d that are bent but not connected to each other. Similar to the above embodiment, the metal fitting 26a and the elastic member are elastically formed at the intersection of the first upper frame 230 and the second upper frame 240, which are in the vicinity of the base ends of the pair of substantially vertical frame portions 240d and 240d constituting the headrest support portion 240e. Both are connected by the connection member 26 provided with the member 26b.

  Also in the present embodiment, since the metal fitting 26a is caulked around the first upper frame 230 and the second upper frame 240 via the elastic member 26b, similarly to the above-described embodiment, a predetermined amount or more is obtained. When an impact is applied, the caulking is released and the impact energy is absorbed by the elastic movement of the elastic member 26b. As the caulking is released, the connecting force between the first upper frame 230 and the second upper frame 240 decreases, and the back frame 20 is more easily deformed than when both are integrated.

  In this state, when the human body enters the indentation space 27 so as to push in the cushion material, the hypotenuse part 240c of the second upper frame 240 is positioned at a height corresponding to the vicinity of the chest (FIG. 12). (See the figure on which the dummy model is seated), which is a resistance that prevents the intrusion of the human body. However, in the present embodiment, since the coupling force between the first upper frame 230 and the second upper frame 240 is rapidly reduced in this way, the resistance force due to the oblique side portion 240c is reduced accordingly. Further, in the present embodiment, the headrest support portion 240e is formed by a pair of substantially vertical frame portions 240d and 240d integrally provided from the oblique side portion 240c of the second upper frame 240, and the substantially vertical frame portions 240d and 240d. However, unlike the above embodiment, they are not connected. Therefore, this configuration also functions to reduce the resistance of the oblique side portion 240c.

  As a result, as in the above-described embodiment, the frame is quickly deformed when receiving an impact of a predetermined level or more, whereby energy is absorbed and the human body is quickly pushed into the intrusion space 27. This increases the amount of movement of the chest and shoulders. As a result, the head is quickly brought into contact with and supported by the headrest, and damage to the neck can be suppressed.

  In addition, as described above, the oblique side portion 240c of the second upper frame 240 is positioned at a height corresponding to the vicinity of the chest portion. Therefore, when the human body is depressed, the oblique side portion 240c is pressed. As described above, the hypotenuse portion 240c does not generate a large reaction force that rebounds the human body even when pressed in this way. However, when the hypotenuse portion 240c is pressed, the headrest is centered around the connecting member 26 portion. The substantially vertical frame portion 240d constituting the support portion 240e is tilted relatively forward. That is, in the present embodiment, when the human body is pushed into the intrusion space 27 due to an impact of a predetermined level or more, the headrest support portion 240e (substantially vertical frame portions 240d and 240d) tilts forward in this way. The headrest supported by the headrest support portion 240e can be brought into contact with and supported by the head more quickly. Therefore, the distance between the boundary of one oblique side 240c and the substantially vertical frame part 240d and the boundary of the other oblique side 240c and the substantially vertical frame part 240d (interval indicated by symbol e in FIG. 10) so that it can be pressed by a human body. Is preferably set in a range of 160 to 190 mm.

  Here, when the substantially vertical frame parts 240d and 240d which comprise the headrest support part 240e are not connected, it lacks in the point of the support force requested | required of a headrest at normal time. However, if the metal substantially vertical frame portions 240d and 240d are directly connected to each other by the metal member, the rigidity becomes too high, and the resistance of the hypotenuse portion 240c when subjected to an impact of a predetermined level or more is increased. Therefore, it is preferable that the substantially vertical frame portions 240d and 240d are connected to each other by the cushion material attaching member 280 formed from the synthetic resin shown in FIG. The cushion material attaching member 280 includes two pipe portions 281 and 281 and connecting portions 282 and 283 spanned between the pipe portions 281 and 281. The two pipe portions 281 and 281 are used by being fitted to the substantially vertical frame portions 240d and 240d. According to this configuration, the substantially vertical frame portions 240d and 240d are connected to each other by the connecting portions 282 and 283. However, since they are made of synthetic resin, the metal substantially vertical frame portions 240d and 240d are directly connected to the metal. The rigidity can be made lower than that in the case where the members are connected to each other, and the resistance force of the hypotenuse portion 240c can be prevented from becoming too high when an impact of a predetermined level or more is applied. The connecting portions 282 and 283 can be made of a cloth (such as canvas) instead of a synthetic resin.

  In this embodiment as well, in order to make it easier for the human body to enter the invagination space 27, the distance between the pair of side frames 21 and 22 is at least 350 mm at the narrowest part, as in the above embodiment. 1 The distance between the vertical frame parts 230b, 230b in the upper frame 230 is at least 300 mm at the narrowest part, and the distance between the horizontal frame part 230a of the first upper frame 230 and the lower frame 25 is at least 500 mm. Is preferred.

  Further, in each of the above-described embodiments, the first upper frames 23 and 230 and the second upper frames 24 and 240 are connected by the connecting member 26 including the elastic member 26b and the metal fitting 26a. This is a structure in which the elastic force of the elastic member 26b is used to quickly reduce the coupling force between the two so that the human body can be quickly inserted into the intrusion space 27. It is. However, the connecting portion is not limited to the connecting means using the elastic member 26b as long as the connecting force between the two is quickly reduced by the input of impact energy. Specifically, as mentioned in the description of the first embodiment, at least one of the first upper frames 23 and 230 and the second upper frames 24 and 240 has a rigidity difference in the same cross section. Both can be connected by welding using a frame. In this case, you may use together the connection member 26 provided with the elastic member 26b. Examples of the method of imparting the difference in rigidity include a method using heat treatment and a method using different plate thicknesses.

  When the method by heat treatment is adopted, the heating time by the heating jig is partially changed in the frame (pipe material) to be processed, or the cooling time is partially changed, so that a highly rigid part can be obtained. Low sites can be formed. FIG. 24A shows a schematic diagram in the case where the pipe material is heated by a heating jig, and the heating jig is provided with two heating portions separated by 180 degrees. FIG. 24B shows the results of measurement with various settings such as the pipe material feed temperature, current, water flow rate, and reached temperature at the time of heating. As a result, No. in FIG. In the sample of No. 6, the hardness (HR15-N) is about 80 (corresponding to a tensile strength of about 1200 MPa) at three points A to C of the pipe material, and the hardness is about 75 (about a tensile strength of about DMP). It can be seen that this corresponds to 950 MPa). This is controlled so that cooling water is applied to point D during heating, and it can be seen that different rigidity can be set in the same cross section of one pipe material by performing such heat treatment. It was.

  Further, as an example of using a different plate thickness, for example, in the first embodiment shown in FIG. 1, the plate thickness of the second upper frame 24 is made thinner than the plate thickness of the first upper frame 23. Examples of welding can be given. As a result, when the impact energy is input, the second upper frame 24 having a smaller plate thickness is deformed more than the first upper frame 23 and tends to move away from the first upper frame 23, resulting in a decrease in connection force due to welding. It becomes easy to do.

  14 to 17 are views showing a seat structure according to a third embodiment of the present invention. In the present embodiment, both the first upper frame 2301 and the second upper frame 2401 are formed in a substantially U shape, and the horizontal frame portions 2301a and 2401a are the same as those in the first embodiment. It is connected by a connecting member 26 having an elastic member 26b. Specifically, the first upper frame 2301 and the second upper frame 2401 are arranged so as to be adjacent to each other in the vertical direction, a substantially U-shaped elastic member 26b is applied to the front side of the both, and the elasticity is further increased. The first upper frame 2301 and the second upper frame 2401 including the member 26b are connected by a metal fitting 26a so as to wrap. Since both the first upper frame 2301 and the second upper frame 2401 are formed in a substantially U shape, a large indentation space 27 is formed in the back frame 20 as in the first embodiment.

  A substantially tubular headrest pole holder 250 is attached to the front surface of the metal fitting 26a of the connecting member 26 by welding. In each headrest pole holder 250, a vertical portion 260a of a substantially U-shaped headrest support portion 260 is inserted and arranged. A lower end portion 260 b of the vertical portion 260 a is provided so as to protrude below the headrest pole holder 250.

  Also in the present embodiment, when an impact greater than a predetermined value is input, the first upper frame 2301 and the second upper frame 2401 are connected by the connecting member 26 having the elastic member 26b. The second upper frame 2401 is relatively easy to move, and the first upper frame 2301 and the second upper frame 2401 are easily deformed. For this reason, the human body quickly enters the intrusion space 27. When the human body further enters the intrusion space 27, the lower end portion 260b of the vertical portion 260a is pushed in as shown in FIG. As a result, the upper end 260c of the headrest support 260 protrudes forward and approaches the head. As a result, the headrest quickly contacts the head.

  18 to 21 are views showing the fourth embodiment, and a headrest pole holder 250 is disposed between the first upper frame 2301 and the second upper frame 2401. Specifically, the headrest pole holder 250 is fixed to the second upper frame 2401 by welding, and the bracket 26a is attached via the elastic member 26b constituting the connecting member 26 so as to surround the first upper frame 2301. The metal fitting 26a is fixed to the headrest pole holder 250.

  Even in such a configuration, the first upper frame 2301 connected via the elastic member 26b is relatively moved with respect to the headrest pole holder 250 when subjected to an impact of a predetermined level or more, as described above. It is easy to move, and the first upper frame 2301 and the second upper frame 2401 are easily deformed. Then, as shown in FIG. 21, when the human body enters the intrusion space 27 and pushes the lower end portion 260b of the vertical portion 260a, the upper end portion 260c protrudes relatively forward. Immediately contact the part. Further, since the joint between the headrest pole holder 250 and the first upper frame 2301 and the second upper frame 2401 is further released, the first upper frame 2301 and the second upper frame are interposed via the headrest pole holder 250 and the connecting member 26. Compared with the rigidity when the frame 2401 is integrated, the rigidity is lowered, the deformation becomes easier, and the impact energy is absorbed.

  In the fourth embodiment, since the metal fitting 26a of the connecting member 26 is merely joined to the headrest pole holder 250, as shown in FIG. A reinforcing connecting member 270 that directly connects the frame 2301 and the second upper frame 2401 may be provided.

  Here, in the case of the third embodiment and the fourth embodiment, the lower end portion 260b of the vertical portion 260a of the headrest support portion 260 causes the headrest pole holder 250 (the first upper frame 2301 and the second Escape backward with the upper frame 2401) as the center. For this reason, the shoulder portion of the human body easily enters the back frame 20.

  On the other hand, as shown in FIGS. 17 and 21, when the lower end portion 260b of the headrest support portion 260 is displaced rearward, the upper end portion 260c is relatively inclined forward. An upper frame 2301 and a second upper frame 2401 are spanned between the side frames 21 and 22 to form a beam. Therefore, a spring feeling due to the deflection of the first upper frame 2301 and the second upper frame 2401 as a beam is given. Moreover, an appropriate spring feeling is provided by adjustment with a part with high rigidity and a low part partially by the above-mentioned heat processing. In addition to the structural damping due to the deformation of each frame described above, the impact is also reduced by such an elastic action. Due to both the elastic action and the damping action, the upper end portion 260c of the headrest support portion 260 is not simply tilted forward, but after being tilted forward and in contact with the head, the state of being in contact with the head is maintained. While maintaining, it will be displaced backward with the deformation of each frame, so the function of suppressing neck damage is high.

(Experimental example)
A whiplash test was performed in which a dummy model was seated on the seat of the test example and the seat of the comparative example. The sheet of the test example is a sheet according to the second embodiment illustrated in FIGS. 9 to 13. As shown in FIG. 23, the sheet of the comparative example is a frame in which substantially vertical frame portions in the sheet of the second embodiment are connected to each other, that is, one second upper frame 240 without being divided in the middle. This is a sheet (comparative example) in which a substantially U-shaped headrest support portion 245 is formed by processing a metal frame. A whiplash test was performed with a dummy model seated on the seats of the test example and the comparative example. The seats of the test example and the comparative example are all the same except for the headrest support portion. As a dummy model, “BioRID-II” (weight of about 78 kg, spine structure: 7 cervical vertebrae, 12 thoracic vertebrae, and 5 lumbar vertebrae) was used.

  The test is based on the JCAP (car assessment) rear impact neck protection performance test, the neck injury index (Neck Injury Criterion) representing the rapidness of head backward movement, after the head contacts the headrest The neck load / moment was measured as an injury index to evaluate from the maximum to the maximum bend, and scored using a score conversion function.

  As a result, the sheet of the test example was 8.1 points and the sheet of the comparative example was 6.8 points, and the test sheet showed a better value. When comparing the shoulder approach amount of the dummy model, the test example sheet has a larger shoulder approach amount than the comparative example sheet, and the chest acceleration is smaller in the test example sheet and larger in the comparative example sheet. It was. From this, the configuration like the seat of the test example in which the human body quickly invades rather than the configuration with a high reaction force like the seat of the comparative example in which the headrest support portion is integrated in a substantially U shape, It can be said that the effect of reducing neck damage (whipping) is high.

DESCRIPTION OF SYMBOLS 1 Seat structure 10 Cushion frame 20 Back frame 21,22 Side frame 23,230,2301 1st upper frame 24,240,2401 2nd upper frame 25 Lower frame 26 Connection member 27 Intrusion space 280 Cushion material attachment member 30 Cushion material 31 Base net 32 Skin 34 Rubber string member 35 Headrest

Claims (13)

A seat structure in which a cushion material is stretched on the back frame,
The back frame is
A pair of side frames formed from a plate-like member having a predetermined width and length, and provided so that the width direction of the plate-like member is substantially along the front-rear direction;
A first upper frame provided with each end connected to an upper end of each front edge of the pair of side frames;
A second upper frame provided with each end connected to the upper end of each rear edge of the pair of side frames;
A lower frame connecting the lower ends of the pair of side frames,
In either the first upper frame or the second upper frame, a headrest support portion formed by bending upward is formed,
In the vicinity of the base end portion of the headrest support portion, the first upper frame and the second upper frame are connected by a connecting member having an elastic member,
Between the pair of side frames and between the connection position by the elastic member in the vicinity of the base end of the headrest support portion and the lower frame, there is no frame, and when a shock exceeding a predetermined level is received A seat structure in which the back of the occupant is an indentation space that indents together with the cushion material. A seat structure in which a cushion material is stretched on the back frame,
The back frame is
A pair of side frames formed from a plate-like member having a predetermined width and length, and provided so that the width direction of the plate-like member is substantially along the front-rear direction;
A first upper frame provided with each end connected to an upper end of each front edge of the pair of side frames;
A second upper frame provided with each end connected to the upper end of each rear edge of the pair of side frames;
A lower frame connecting the lower ends of the pair of side frames,
In either the first upper frame or the second upper frame, a headrest support portion formed by bending upward is formed,
The first upper frame and the second upper frame are connected to each other in the vicinity of the base end portion of the headrest support portion, and at least one of the first upper frame and the second upper frame is within the same cross section at this connection position. It has parts with different rigidity,
Between the pair of side frames, between the connection position in the vicinity of the base end of the headrest support portion and the lower frame, no frame is arranged, and when the vehicle receives an impact of a predetermined level or more, A seat structure characterized in that the back is an indentation space that indents together with the cushion material. The first upper frame includes a horizontal frame portion extending substantially horizontally, and a vertical frame extending downward from each end portion of the horizontal frame portion and coupled to each front edge upper end portion of the pair of side frames. A headrest support portion that is bent in a substantially inverted U shape at a substantially central portion of the lateral frame portion,
The second upper frame includes a horizontal frame portion extending substantially horizontally, and a vertical frame extending downward from each end portion of the horizontal frame portion and coupled to upper end portions of the rear edges of the pair of side frames. And a structure having
The part adjacent to the base end part of the said headrest support part among the horizontal direction frame parts in the said 1st upper frame, and the horizontal direction frame part of the said 2nd upper frame are connected. Seat structure.   The distance between the pair of side frames is at least 350 mm at the narrowest portion, and the narrower distance between the vertical frame parts in the first upper frame and the vertical frame parts in the second upper frame is the smallest. The narrowest portion is at least 300 mm, and the lower frame includes a horizontal frame portion positioned below one of the horizontal frame portion of the first upper frame and the horizontal frame portion of the second upper frame, and the lower frame. The seat structure according to any one of claims 1 to 3, wherein the distance is at least 500 mm.   3. The seat structure according to claim 2, wherein portions having different rigidity in the same cross section set in at least one of the first upper frame and the second upper frame are set by changing heat treatment conditions.   Further, the first upper frame and the second upper frame are welded, and the welded portion is a portion having low rigidity in the same cross section set in at least one of the first upper frame and the second upper frame. The seat structure according to claim 5. A seat structure in which a cushion material is stretched on the back frame,
The back frame is
A pair of side frames formed from a plate-like member having a predetermined width and length, and provided so that the width direction of the plate-like member is substantially along the front-rear direction;
A first upper frame provided with each end connected to an upper end of each front edge of the pair of side frames;
A second upper frame provided with each end connected to the upper end of each rear edge of the pair of side frames;
A lower frame connecting the lower ends of the pair of side frames,
The first upper frame includes a horizontal frame portion extending substantially horizontally, and a vertical frame extending downward from each end portion of the horizontal frame portion and coupled to each front edge upper end portion of the pair of side frames. And a structure having
The second upper frame includes a pair of oblique sides bent obliquely upward and inward from the respective rear edge upper ends of the side frames, and is bent upward from the inner ends of the pair of oblique sides. On the other hand, it is a structure having a headrest support portion having a pair of substantially vertical frame portions that are not connected to each other,
A seat characterized in that the first upper frame and the second upper frame are connected to each other by a connecting member having an elastic member in the vicinity of a base end portion of a pair of substantially vertical frame portions constituting the headrest support portion. Construction. A seat structure in which a cushion material is stretched on the back frame,
The back frame is
A pair of side frames formed from a plate-like member having a predetermined width and length, and provided so that the width direction of the plate-like member is substantially along the front-rear direction;
A first upper frame provided with each end connected to an upper end of each front edge of the pair of side frames;
A second upper frame provided with each end connected to the upper end of each rear edge of the pair of side frames;
A lower frame connecting the lower ends of the pair of side frames,
The first upper frame includes a horizontal frame portion extending substantially horizontally, and a vertical frame extending downward from each end portion of the horizontal frame portion and coupled to each front edge upper end portion of the pair of side frames. And a structure having
The second upper frame includes a pair of oblique sides bent obliquely upward and inward from the respective rear edge upper ends of the side frames, and is bent upward from the inner ends of the pair of oblique sides. On the other hand, it is a structure having a headrest support portion having a pair of substantially vertical frame portions that are not connected to each other,
The first upper frame and the second upper frame are connected to each other in the vicinity of the base end portions of the pair of substantially vertical frame portions constituting the headrest support portion, and at the connection position, the first upper frame and the second upper frame are connected. A seat structure characterized in that at least one of the frames has a portion having different rigidity in the same cross section.   The distance between the pair of side frames is at least 350 mm at the narrowest portion, and the distance between the vertical frame portions in the first upper frame is at least 300 mm at the narrowest portion, The seat structure according to claim 7 or 8, wherein a distance between the direction frame portion and the lower frame is at least 500 mm.   The distance between the boundary of one oblique side and the substantially vertical frame part and the boundary of the other oblique side and the substantially vertical frame part in the second upper frame is set to be in a range of 160 to 190 mm. The seat structure according to any one of 7 to 9.   It comprises two pipe parts formed from synthetic resin and a connecting part spanned between the pipe parts and formed from synthetic resin or fabric, and the two pipe parts constitute the headrest support part The seat structure according to any one of claims 7 to 10, further comprising a cushion material mounting member for a headrest that is fitted and disposed in a substantially vertical frame portion.   The seat structure according to claim 8, wherein portions having different rigidity in the same cross section set in at least one of the first upper frame and the second upper frame are set by changing heat treatment conditions.   Further, the first upper frame and the second upper frame are welded, and the welded portion is a portion having low rigidity in the same cross section set in at least one of the first upper frame and the second upper frame. The seat structure according to claim 12.

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