JP6090002B2 - Vehicle seat - Google Patents

Description

  The present invention relates to a vehicle seat including a seat back that supports a back of a seated person and a headrest that supports a head.

  A separate headrest used for a general vehicle seat is attached to the seat back via a rod-like stay that protrudes from the headrest. When the height of the headrest can be adjusted, a generally cylindrical headrest support made of resin for inserting the stay is further used. A metal cylindrical attachment member called a support bracket is welded to the frame of the seat back, and the headrest support is inserted into the bracket. A seat having such a bracket and a headrest support is disclosed in, for example, Patent Document 1 below.

  In the technique of this document, a bracket having a certain length in the vertical direction is welded to the seat back frame at two positions on the upper and lower sides, thereby increasing the range of the joint and increasing the rigidity. As a result, when the vehicle receives a rear-end collision, the headrest of the seated person can be reliably received by the headrest, thereby preventing the occurrence of whipping.

JP-A-11-216037

  Generally, the floor panel vibrates at a specific frequency due to the engine when the vehicle is running or idling. This vibration is also transmitted to the headrest via a seat frame attached to the floor panel. The natural frequency at which the headrest particularly easily vibrates with respect to the seat back frame increases as the rigidity of the coupling portion of the bracket to the seat back frame increases. Therefore, when the above technique is used, there is a problem that the natural frequency of the headrest reaches the vicinity of the frequency of the floor panel, and the headrest tends to resonate with the floor panel, thereby amplifying the vibration.

  In order to reduce the resonance level of the headrest, it is conceivable to lower the rigidity of the coupling portion of the bracket. However, if the rearward rigidity is weak, the joint part will bend to the inertial force of the seated person's head or headrest when receiving a rear-end collision, and the headrest cannot be reliably supported by the headrest. On the other hand, if the rigidity of the front is weak, for example, when a seat occupant of the rear seat grabs or leans on the headrest of the front seat and a load is applied, the joint portion is permanently deformed and the headrest orientation changes. The quality of the sheet is impaired.

  On the contrary, the natural frequency of the headrest can be lowered by increasing the mass of the headrest. However, this increases the mass of the sheet and the manufacturing cost, which is not a preferable means.

  The present invention has been made in view of such problems, and the problem to be solved by the present invention is a headrest that is not excessively inclined with respect to the force applied in the front-rear direction while suppressing resonance. There is.

  The vehicle seat obtained from one aspect of the present invention is provided with an upper frame member and a lower frame member that extend in parallel with the width direction of the seat back as a skeleton of the seat back. A longitudinally extending attachment member for attaching the headrest to the seat back intersects in front of the upper frame member and is joined to the lower frame member, but not directly to the upper frame member. When the rearward force is applied to the headrest, the upper frame member receives the attachment member on the front surface so that the headrest is prevented from tilting backward.

  Since the headrest attachment member is not coupled to the upper frame member in this manner, the rigidity of the coupling portion is lowered, and the natural frequency of the headrest can be lowered. Therefore, vibration can be suppressed if the natural frequency is sufficiently lower than the peak of the amplification factor of resonance. On the other hand, since the upper frame member constituting the seat back frame receives the attachment member on the front surface, the seated person can be reliably supported when the vehicle receives a rear collision.

  In addition, the attachment member and the upper frame member are restrained by a band made of a belt or a string, and when a forward force is applied to the headrest, the headrest is restricted from being tilted forward by the tension of the band. Yes.

  As described above, since the band is provided as a means for restricting the attachment member from tilting forward, it is possible to suppress deformation of the joint portion of the attachment member when the occupant applies a large load to the headrest.

  As one aspect, the band has loops at both ends, the second loop is passed through the first loop, the upper frame member passes through a third loop formed by an intermediate parallel portion, It is preferable that the mounting member is in a state of passing through the loop 2. The loops at both ends can be easily formed by narrowing the loop by, for example, using a closed ring-shaped band and pulling the opposite sides. Since the middle parallel part is wrapped around the upper frame, it is firmly restrained. Since the root of the second loop is narrowed by the first loop, the ring is tightened and the restraining force on the bracket is also increased.

  As another aspect, it is preferable that the first loop is disposed downward between the upper frame member and the attachment member, and the second loop is passed from below the upper frame member to the first loop. . According to this, the second loop 62 passed through the bracket 36 is held on the lower side compared to the case of the upside down direction, and it is difficult to come out of the bracket 36.

It is a perspective view which shows the sheet | seat as one aspect of this invention. It is a perspective view from the diagonal front which shows the state which restrained the headrest bracket and the upper frame with the band. It is a perspective view from the slanting bottom which shows the state which restrained the headrest bracket and the upper frame with the band. It is a side view from the left which shows the state which restrained the headrest bracket and the upper frame with the band. It is a graph explaining the effect by lowering the natural frequency of a headrest. It is a graph explaining the relationship between the force applied to the headrest and the displacement. It is the perspective view from the back which shows the state which restrained the headrest bracket and the upper frame with the band by another method. It is a figure which shows the example of the band which has a loop in both ends beforehand.

  Hereinafter, various aspects of the present invention will be described with reference to the drawings. In FIG. 1, the outer shape of the sheet 10 according to one embodiment of the present invention is indicated by a chain line. The seat 10 includes a seat cushion 20 on which an occupant sits, and a seat back 30 that supports the back of the seated person is connected to an end of the seat cushion 20. A headrest 40 (see FIG. 7) that supports the head is mounted on the seat back. The seat back 30 is provided with a metal seat back frame 31 (hereinafter referred to as a frame) as shown by a solid line in FIG. 1 as a skeleton, and the frame 31 is covered with a cushioning pad material and has an outer shape including a backrest surface. Form. The frame 31 and the pad material are covered with a skin material for providing touch and design. The seat 10 according to the aspect of the present invention is particularly effective when installed in an automobile, but can also be used in general vehicles such as railway vehicles.

  In addition, the front-rear direction regarding the seat 10 used in the following description is determined with the side where the seat back 30 is connected to the seat cushion 20 as the rear, and the direction in which the seat 10 is installed with respect to the traveling direction of the vehicle Is not limited. However, in the discussion regarding the direction of the force received when the vehicle receives a rear-end collision, it is assumed that the seat 10 is installed toward the front of the vehicle.

[Frame structure]
The frame 31 is provided with upper and lower frame members extending in parallel with at least the width direction of the seat back 30 at the upper part. Such a frame 31 includes, as an example, a generally rectangular frame structure disposed on the outer periphery of the seat back, and a reinforcing member 35 spanned between the side portions 32b in parallel with the upper side portion 32a. be able to.

  As an example, the frame structure described above can be configured by integrally joining the upper frame 32, the left and right side frames 33, and the under frame 34 to each other by welding. The side frame 33 is a vertically long plate-like member and constitutes a side part 32b of the frame structure. The upper frame 32 is a pipe material having a circular cross section and is bent in a generally U shape, and constitutes from the upper side part 32a of the frame structure to the upper part of the left and right side parts 32b. The upper frame 32 is welded so as to connect the upper ends of the left and right side frames 33. The under frame 34 is a plate-like long member that constitutes the lower side of the frame structure and is welded to the inner surfaces of the lower portions of the left and right side frames 33.

[Headrest mounting structure]
As shown in FIG. 7, the headrest 40 includes a stay 41 made of a metal rod extending downward. For example, the headrest 40 is attached to the frame 31 via a headrest stay 41, a resin headrest support 37 (hereinafter referred to as a support), and a metal support bracket 36 (hereinafter referred to as a bracket). The bracket 36 is a cylindrical member having a certain length in length so that the support 37 can be inserted from above. The bracket 36 is disposed across the front of the upper frame 32 and is coupled to the reinforcing member 35 at the lower part. A support 37 having a generally columnar (for example, cylindrical) outer shape can be inserted into the bracket 36, while a through hole into which the stay 41 of the headrest 40 can be inserted is provided at the center. The support 37 and the stay 41 are provided with known means for adjusting the position of the headrest 40 to a desired height, and a plurality of positions with respect to the support 37 in a state where the stay 41 is inserted into the through hole of the support 37. It can be locked with.

[Measures against headrest vibration]
When a force in the front-rear direction is applied to the headrest 40, the bracket 36 into which the stay 41 and the support 37 are inserted is considered to be hardly deformed, so that the coupling portion (including the reinforcing member 35) to the frame 31 is slightly. Therefore, the headrest 40 is tilted according to the magnitude and direction of the force. Thus, the behavior when a force of a certain level is applied to the headrest 40 can be considered by a model in which the headrest 40 is elastically supported with respect to the frame 31.

  The higher the rigidity of the coupling portion, the greater the natural frequency when the headrest 40 vibrates with respect to the frame 31. As shown in FIG. 5, the closer the frequency is to the frequency f1 of the floor panel, the greater the amplification factor of the vibration level when the headrest 40 resonates with the floor panel. If the bracket 36 is coupled to both the upper frame 32 and the reinforcing member 35, the peak value of the amplification factor may increase and reach f1 as shown by the broken line. On the other hand, when the bracket 36 is substantially supported only by the reinforcing member 35 as described above, since the rigidity of the coupling portion is weak, the peak value is lower than f1 as shown by the solid line, and the amplification is performed. The rate can be lowered from the conventional point a to point b. As a result, the degree of resonance of the headrest 40 that can occur during traveling of the vehicle or the like is suppressed.

[Backward tilt restriction]
When a large rearward force is applied to the headrest 40, the bracket 36 tilts rearward and hits the upper frame 32. That is, the upper frame 32 disposed behind the bracket 36 functions as a means for restricting the bracket 36 from tilting backward. Therefore, when the vehicle is subjected to a rear-end collision and a rearward impact force is applied to the headrest 40 due to the inertial force of the seated person's head, the upper frame 32 receives the upper part 36a of the bracket 36 to ensure the seated person's head. Can be supported. In particular, since the bracket 36 is not coupled to the upper frame 32, it is not necessary to partially collapse the pipe shape of the upper frame 32 to provide a plane for welding. Therefore, even if the upper frame 32 receives a strong force from the bracket 36 when the rearward collision occurs, the headrest 40 exhibits a good support performance due to the bending strength inherent in the pipe shape.

[Forward tilt regulation]
As shown in FIGS. 2 and 7, the seat 10 according to the embodiment of the present invention has a bracket 36 and an upper frame 32 as means for restricting the bracket 36 from tilting forward when a forward force is applied to the headrest 40. Bands 60 and 260 for restraining (binding) are provided. When a forward force is applied to the headrest 40, the bracket 36 is prevented from being tilted forward by the tension of the bands 60 and 260.

If such a restricting means is not provided, when a large forward force F acts on the headrest 40 as shown in FIG. 6, the joint to the frame is greatly plastically deformed as shown by the broken line graph. If regulation is started when the bracket 36 is tilted forward by a certain amount s ₂ or more as shown by the solid line graph, the direction of the headrest 40 will change greatly even if a large load F is applied, and it will become unusable. Will disappear. Further, as described above, since the rigidity of the joint portion of the headrest 40 to the frame 31 is reduced, it is not preferable to constrain the band tightly. As shown in FIG. 7, even if the band is not sandwiched between the bracket 36 and the upper frame 32, the band is designed to have a sufficient restraining force so as not to interfere with minute vibrations so that a gap is formed. It is good to do.

  The band is made of a material such as a belt or a string having a flexibility that can be wound around or hooked to the bracket 36 or the upper frame 32. The belt and the strap constituting the band are preferably made of a material having a tensile strength, and specifically, a cloth such as a woven fabric is preferably used. However, other materials such as leather can be used depending on circumstances. As the woven fabric, it is particularly preferable to use a polyester fiber woven fabric having a high tensile strength, which is also used for a seat belt.

  It may be fixed by simply wrapping around the bracket 36 and the upper frame 32 using a band made of a single belt or string, and connecting both ends, but in the following, as shown in FIG. 3 and FIG. An example in which closed annular bands 60 and 260 are used will be described. The closed annular band 260 can be manufactured by simply joining the ends of a single belt or string. If it is a belt, it is easy to connect by sewing as shown by a thick broken line in FIG. In some cases, a similar ring-shaped band can be obtained by cutting a tubular fabric woven from the beginning to the endless width using a bag weaving technique.

  To bind as shown in FIG. 2 using the closed ring-shaped band 60, first, the opposite side of the ring-shaped band 60 is drawn to narrow the ring, and loops 61 and 62 (folded) are formed at both ends. Next, hold both loops 61 and 62 with their respective hands, wind the intermediate parallel portion around the upper frame 32 about a half turn, and then completely connect the other (second) loop 62 to one (first) loop 61. Pass through. Thereby, as shown in FIGS. 2 and 3, the upper frame 32 passes through the third loop 63 formed by the intermediate parallel portion. Finally, the second loop 62 is hung on the bracket 36. Since an intermediate parallel portion is wound around the upper frame 32, the upper frame 32 is firmly restrained. Since the root of the second loop 62 is narrowed by the first loop 61, the ring is tightened and the restraining force on the bracket 36 is also increased.

  Depending on which loop is passed through which loop in the second step above, two binding states can be obtained. Here, when the parallel part is wound from behind the upper frame 32, it is preferable to pass the (second) loop 62 coming from below through the (first) loop 61 coming from above. Accordingly, as shown in FIG. 4, one (first) loop 61 faces downward between the upper frame 32 and the bracket 36, and the other (second) loop 62 extends from the bottom of the upper frame 32 to the first loop 61. 1 is passed through the loop 61. By intentionally selecting this between the two bound states, the (second) loop 62 passed through the bracket 36 can be held on the lower side, and can be made difficult to come off from the bracket 36. Therefore, even if the operator accidentally touches the band 60 in the process of attaching the pad material in the stage before attaching the support 37 (see FIG. 7), it is difficult to come off. In addition, since the (first) loop 61 exists between the bracket 36 and the upper frame 32, both members made of metal are less likely to be in direct contact with each other, and harsh metal sounds due to vibration are less likely to occur. Become. If the vibration can be absorbed by the buffering action of the band 60, it is expected that the amplification factor will be further smaller than the point b in FIG.

  To bind as shown in FIG. 7 using the closed ring-shaped band 260, the ring-shaped band 260 is first hung on the bracket 36 and lowered to a position lower than the upper frame member. Next, one part of the band 260 is pulled back by hand to narrow the ring, and the intermediate parallel part is turned upward from the rear side of the upper frame member. As a result, loops 261 and 262 are formed at both ends, and the bracket 36 passes through one (first) loop 261. Finally, the other (second) loop 262 held by hand is hung on the bracket 36. As a result, the upper frame 32 passes through the third loop 263 formed by the intermediate parallel portion.

  This second method (FIG. 7) is simpler than the first method (FIG. 2) and can be operated with one hand. However, as shown in FIG. 7, if the operator accidentally touches the band 260 before attaching the support 37 (shown by a two-dot chain line), the loop (262) hung on the upper side is likely to come off. Further, since the bracket 36 and the upper frame 32 can be in direct contact with each other, sound or vibration may be absorbed by providing a cushioning material made of felt or rubber on the surface of any member as described above.

  In addition, this invention is not limited to the aspect demonstrated above, In other various aspects, it can implement. For example, if it is not necessary to make the height of the headrest adjustable, the headrest mounting member in the present invention may be constituted by only the stay 41, for example, and the stay 41 may be directly welded to the reinforcing member 35 and coupled. Good.

  Instead of the closed ring-shaped band used above, a band 360 having loops 361 and 362 at both ends in advance may be used as shown in FIG. Such a band 360 can be manufactured, for example, by folding and sewing each end of one belt. The third loop described above is mainly created by the middle single portion 363.

DESCRIPTION OF SYMBOLS 10 Seat 30 Seat back 31 Seat back frame 32 Upper frame 35 Reinforcement member 36 Bracket 37 Headrest support 40 Headrest 41 Headrest stay 60 Bands 61, 62, 63 Loop

Claims (2)

A vehicle seat comprising a seat back that supports the back of a seated person and a headrest that supports the head,
An upper frame member and a lower frame member extending in parallel with the width direction of the seat back are provided as a skeleton of the seat back,
A longitudinally extending attachment member for attaching the headrest to the seat back intersects in front of the upper frame member and is coupled to the lower frame member, but not directly coupled to the upper frame member. When the rearward force is applied to the upper frame member, the upper frame member receives the attachment member on the front surface so that the headrest is tilted backwards,
The attachment member and the upper frame member are restrained by a band made of a belt or a string, and when a forward force is applied to the headrest, the headrest is restricted from being tilted forward by the tension of the band ,
The band has loops at both ends, the second loop is passed through the first loop, the upper frame member passes through the third loop formed by the middle portion, and the attachment member is passed through the second loop. A vehicle seat characterized by having passed through . The vehicle seat according to claim 1 ,
A vehicle seat characterized in that a first loop is disposed downwardly between the upper frame member and the attachment member, and a second loop is passed from below the upper frame member to the first loop. .

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