JP6044480B2 - Vehicle seat - Google Patents

Description

  The present invention relates to a vehicle seat having a function of reducing vibration generated in a seat frame due to vibration from a vehicle body side.

Vibration is generated in a vehicle seat provided on a vehicle such as a vehicle due to factors such as engine vibration. In order to maintain a more comfortable seating state for the occupant, it is desirable to further reduce the vibration of the vehicle seat on which the occupant is seated.
Therefore, the conventional technique described in Patent Document 1 discloses a vehicle seat that can absorb and reduce vibration generated in the vehicle seat by using a dynamic damper.

JP 2010-95054 A

In the prior art described in Patent Document 1, the vibration transmitted from the vehicle body to the vehicle seat is transmitted to the dynamic damper to resonate, thereby converting the vibration of the vehicle seat into the vibration of the dynamic damper. Absorbs vibrations.
The dynamic damper is composed of a seat pad and a mass sandwiched between the seat pads, and the addition of this mass causes an increase in seat weight.
The present invention was devised in view of such points, and it is an object of the present invention to provide a vehicle seat that can reduce vibration generated in a seat frame due to vibration from the vehicle body side while suppressing an increase in seat weight as much as possible. To do.

According to a first aspect of the present invention, a seat back frame of a vehicle seat is divided into upper and lower parts to form an upper member and a lower member, and the upper member is coupled to the lower member by a hinge shaft so as to be rotatable in the front-rear direction. In addition, an elastic means for urging to maintain the seat back frame shape in a normal posture state when the passenger is seated is provided between the upper member and the lower member.
According to the first invention, the seat back frame is divided into two and elastically supported, whereby the rigidity of the seat back frame can be lowered, and the resonance frequency of the seat back frame is lowered accordingly. As a result, the vibration frequency of the vibration transmitted from the engine in the idling state is separated from the resonance frequency of the seat back frame, and the vibration of the seat back when the vehicle is stopped can be reduced to improve the sitting comfort. At this time, no addition of mass or the like is necessary, so that an increase in sheet weight can be suppressed as much as possible.

According to a second aspect of the present invention, in the vehicle seat according to the first aspect of the present invention, when an excessive impact load is applied to the seat back frame, stopper means for restricting rotational deformation of the upper member relative to the lower member is provided. It is provided between the upper member and the lower member.
According to the second aspect of the invention, in addition to the effects of the first aspect of the invention, when an excessive impact load is applied to the seat due to a vehicle collision or the like, the back frame is prevented from being greatly deformed.

According to a third aspect of the present invention, in the vehicle seat according to the second aspect, the elastic means and the stopper means are elastic members that support the upper member and the lower member at positions different from the hinge shaft. It is the elastic member and the shaft in the interposed shaft.
According to the third aspect of the present invention, the upper member and the lower member are coupled by a shaft through a hinge shaft that can be rotated in the front-rear direction and an elastic member that is supported at a position different from the hinge shaft. Is concise.

According to a fourth aspect of the present invention, in the vehicle seat according to the third aspect, the elastic member is a rubber bush and the shaft is a bolt.
According to the fourth invention, in addition to the effects of the third invention, the seat back frame can be assembled by a simple method in which a bolt is passed through a hole provided in the upper member and the lower member via a rubber bush and fixed with a nut. it can.

1 is a perspective view of a first embodiment of the present invention. It is a side view of the principal part of the said embodiment. It is sectional drawing cut | disconnected and shown by the III-III line of FIG. It is a side view of the principal part of 2nd Embodiment. It is sectional drawing cut | disconnected and shown by the VV line | wire of FIG. It is a graph explaining the fall of the vibration magnification of the seat back in the composition of an embodiment.

1 to 3 show a first embodiment of the present invention.
In FIG. 1, the outer shape of the vehicle seat 10 is indicated by a two-dot chain line. The seat 10 includes a seat cushion 20 on which an occupant sits, a seat back 30 that serves as a back of the occupant, and a headrest 40 (see FIG. 2) that supports the occupant's head. The seat back 30 is connected to a rear end portion of the seat cushion 20, and an angle formed with respect to the seat back 30 can be adjusted by a recliner (not shown) provided in the connecting portion.
The seat back 30 includes a metal seat back frame 31 having a substantially rectangular frame shape when viewed from the front as shown by a solid line in FIG. Further, the seat back 30 includes a pad material that is a cushion material covering the seat back frame 31 and a skin material that covers the pad material as members that form an outer shape (indicated by a two-dot chain line in FIG. 1) including a backrest surface. Have. A headrest 40 that supports the back of the seated person is attached to the upper portion of the seat back 30.

The seat back frame 31 includes an upper frame 32 and a lower frame 33. The upper frame 32 and the lower frame 33 correspond to an “upper member” and a “lower member” recited in the claims.
The upper frame 32 includes a pair of upper side frames 32a and an upper upper frame 32b. The upper side frame 32a is a plate-like member disposed in the vertical direction on the left and right sides, and ribs (standing walls) directed toward the inner side of the seat are provided at front and rear ends. The upper upper frame 32b is a member obtained by bending a pipe having a circular cross section into a substantially U-shape, and is arranged so as to connect the upper ends of the pair of upper side frames. The upper upper frame 32b is provided with a pair of headrest support brackets 32d for attaching the reinforcing member 32c and the headrest 40.
The lower frame 33 includes a pair of lower side frames 33a and a lower under frame 33b. The lower side frame 33a is a plate-like member disposed in the vertical direction on the left and right sides, and ribs (standing walls) directed toward the inner side of the seat are provided at the front and rear ends. The lower under frame 33b is a long plate-shaped member, and is disposed so as to connect the lower rear ribs of the left and right lower side frames 33a.

A coupling structure of the upper frame 32 and the lower frame 33 will be described with reference to FIGS. Since the left and right have the same structure, the left frame will be described.
An extending portion 32 a 1 is provided at the lower portion of the pair of upper side frames 32 a of the upper frame 32. The extended portion 32a1 is a portion for overlapping the extended portion 33a1 provided on the lower side frame 33a of the lower frame 33 to couple them together. A rib (standing wall) directed toward the inner side of the sheet is not provided at the end of the extended portion 32a1. A bolt 32 is inserted into the extended portion 32 a 1 through a rubber bush 47 and a hole 32 a 2 for inserting a bolt 34 that couples the upper side frame 32 a to the lower side frame 33 a so as to be rotatable in the front-rear direction. A hole 32a3 is opened. The diameter of the hole is approximately equal to the diameter of the bolt 34 at the hole 32 a 2 and approximately equal to the diameter of the rubber bush 47 through which the bolt 32 passes the hole 32 a 3. As for the arrangement of the holes, the hole 32a2 is provided below the hole 32a3.
An extending portion 33 a 1 is provided on the upper portion of the pair of lower side frames 33 a of the lower frame 33. The extended portion 33a1 is a portion for overlapping the extended portion 32a1 provided at the lower part of the upper side frame 32a of the upper frame 32 to couple them together. A rib (standing wall) directed inward of the sheet is not provided at the end of the extended portion 33a1. Bolts 44 a are inserted into the extending portions 33 a 1 through holes 33 a 2 for inserting bolts 34 that couple the upper side frame 32 a to the lower side frame 33 a so as to be pivotable in the front-rear direction, and rubber bushes 47. A hole 33a3 is opened. The diameter of the hole is substantially the same as the diameter of the rubber bush 47 through which the hole 33a2 is substantially equal to the diameter of the bolt 34 and the hole 33a3 is passed through the bolt 44. As for the arrangement of the holes, the hole 33a2 is provided below the hole 33a3.
The holes 32a2 and 32a3 of the upper side frame 32a have the same diameter as the holes 33a2 and 33a3 of the lower side frame 33a, respectively, and the pitch of the holes 32a2 and 32a3 is the same as the pitch of the holes 33a2 and 33a3. Further, when the extended portion 32a1 of the upper side frame 32a and the extended portion 33a1 of the lower side frame 33a are overlapped to make the holes 32a2 and 33a2 and the holes 32a3 and 33a3 coincide with each other, the upper frame 32 and the lower frame 33 Each hole position is set so that the form is in the normal posture state when the occupant is seated.
The extending portion 33a1 of the lower side frame 33a is disposed outside the extending portion 32a1 of the upper side frame 32a so that the holes are aligned with each other, and the bolt 34 is inserted into the hole 32a2 and the hole 33a2 from one side via the washer 36. And is fastened with a nut 35 via a washer 36 on the opposite side. The bolt 34 corresponds to a “hinge shaft” recited in the claims. Further, the rubber bush 47 is inserted into the hole 32a3 and the hole 33a3, and the bolt 44 is inserted from one side through the washer 46, and is fastened by the nut 45 through the washer 46 on the opposite side. The rubber bush 47 corresponds to “elastic means” described in the claims, and the bolt 44 corresponds to “stopper means” described in the claims.

The embodiment configured as described above has the following operational effects.
In general, a vehicle floor panel resonates at a specific frequency with an idling engine, and this vibration is applied to the seat through a seat cushion frame fixed to the floor panel regardless of whether an occupant is seated on the seat. It is also transmitted to the back frame 31. The resonance frequency of the seat back frame 31 increases as the rigidity thereof increases. As shown in FIG. 6, the closer the resonance frequency is to the resonance point of the floor panel, the more the vibration level of the floor panel is amplified and the vibration starts. In the diagram shown in FIG. 6, assuming that the resonance frequency of the floor panel at the time of general engine idling is f1, the resonance frequency in the case of the conventional seat back frame indicated by the broken line is substantially the same position as the above f1. Vibration is most amplified and transmitted to the seat back frame. On the other hand, in the present embodiment, the seat back frame 31 is divided into two parts, an upper frame 32 and a lower frame 33, which are hingedly coupled by a bolt 34 so as to be rotatable, and at a different position via a rubber bush 47. Are connected by bolts 44. As a result, the upper frame 32 and the lower frame 33 are maintained in shape by the elasticity of the rubber bush 47, and the rigidity of the seat back frame 31 in the front-rear direction is weakened. From this, the resonance frequency is lowered as shown by the solid line in FIG. 6, and the vibration magnification of the seat back frame 31 can be lowered from the conventional point a to point b. As a result, it is possible to improve seating comfort by reducing the vibration of the seat back that occurs during engine idling. Further, even if an excessive impact load is applied to the seat back frame 31 due to a vehicle collision or the like, and the rubber bush 47 exceeds the elastic limit, the metal bolt 44 passes through the center portion. Therefore, the seat back frame 31 is not excessively deformed as compared with the conventional seat back frame.

4 and 5 show a second embodiment of the present invention. Regarding the same configuration as that of the first embodiment, the same reference numerals are given to the drawings, and the description thereof is omitted.
The coupling structure of the upper frame 32 and the lower frame 33 is as follows. The extended portion 32a1 of the upper side frame 32a has a hole 32a2 for inserting a bolt 34 for coupling the upper side frame 32a to the lower side frame 33a so as to be rotatable in the front-rear direction, and one end of a coil spring 137. A hole 32a4 for inserting and fixing the pin 138 to be locked is opened. The diameter of the hole is such that the hole 32a2 is approximately equal to the diameter of the bolt 34, and the hole 32a4 is slightly smaller than the diameter of the pin 138 and can be held unrotatable when the pin 138 is driven. As for the arrangement of the holes, the hole 32a2 is provided below the hole 32a4.
The extending portion 33a1 of the lower side frame 33a has a hole 33a2 for inserting a bolt 34 for connecting the upper side frame 32a to the lower side frame 33a so as to be pivotable in the front-rear direction, and an upper side thereof as will be described later. In addition, an arc-shaped elongated hole 33a5 that allows the upper side frame 32a to move in the front-rear direction with respect to the lower side frame 33a through the pin 138 is opened. Further, a hole 33a4 for inserting and fixing a pin 139 for locking the other end of the coil spring 137 is formed in the center of the arcuate hole 33a5 below the hole 33a2 and the lower side frame 33a on the extension line of the hole 33a2. It is dawned. The diameter of the hole is such that the hole 33a2 is substantially equal to the diameter of the bolt 34, and the hole 33a4 is slightly smaller than the diameter of the pin 139 and can be held unrotatable when the pin 139 is driven.
When the extending portion 32a1 of the upper side frame 32a and the extending portion 33a1 of the lower side frame 33a are overlapped to align the center of the hole 32a2, the hole 33a2, the hole 32a4, and the arc-shaped long hole 33a5, Each hole position is set so that the form of the lower frame 33 is in a normal posture state when the occupant is seated.
The coil spring 137 is made of metal, and both ends of the coil spring 137 extend substantially on the same line. Further, a pin 138 is held in the hole 32a4 of the upper side frame 32a, and a pin 139 is held in the hole 33a4 of the lower side frame 33a in a non-rotatable manner. In this state, the upper side frame 32a and the lower side frame 33a are arranged so as to be in the normal posture when the occupant is seated, and the bolts 34 are inserted into the holes 32a2 and 33a2 through the washers 36 from one side. The other side is fastened with a nut 35 via a washer 36. Further, the center of the coil portion of the coil spring 137 is aligned with the center of the bolt 34, one end thereof is locked to the pin 138, and the other end is fixed to the pin 139.

  In the second embodiment as described above, similarly to the first embodiment, the shape of the upper frame 32 and the lower frame 33 is maintained by the elasticity of the coil spring 137, and the rigidity in the front-rear direction of the seat back frame 31 is weakened. It has a structure. From this, the resonance frequency is lowered as shown by the solid line in FIG. 6, and the vibration magnification of the seat back frame 31 can be lowered from the conventional point a to point b. As a result, it is possible to improve seating comfort by reducing the vibration of the seat back that occurs during engine idling. Further, even when an excessive impact load is applied to the seatback frame 31 due to a vehicle collision or the like, the pin 138 fixed to the upper side frame 32a also has an arc-like length of the lower side frame 33a even when the coil spring 137 tries to deform greatly. Since it is stopped at the end of the hole 33a5, the seat back frame 31 is not deformed excessively as compared with the conventional seat back frame.

As mentioned above, although specific embodiment was described, this invention is not limited to those structures, A various change, addition, and deletion are possible in the range which does not change the summary of this invention. For example,
1. In the first embodiment, the position of the shaft via the rubber bush with respect to the hinge shaft may be either up or down. Further, although bolts and nuts are used as the shafts, a method may be adopted in which a pin fixed to either the upper side frame or the lower side frame and a hole provided in another member are passed.
2. In the second embodiment, the position of the pin 138, the arc-shaped long hole 33a5, and the pin 139 with respect to the hinge shaft may be any of up / down and front / back as long as they can be arranged. Further, a leaf spring can be used instead of the coil spring.

DESCRIPTION OF SYMBOLS 10 Vehicle seat 20 Seat cushion 30 Seat back 31 Seat back frame 32 Upper frame 32a Upper side frame 32a1 Extension part 32a2 Hole 32a3 Hole 33 Lower frame 33a Lower side frame 33a1 Extension part 33a2 Hole 33a3 Hole 33a4 Hole 33a5 Arc-shaped Long hole 34 bolt (hinge shaft)
35 Nut 36 Washer 44 Bolt (stopper means)
45 Nut 46 Washer 47 Rubber bush (elastic means)

Claims (2)

A seat back frame of a vehicle seat is divided into an upper member and a lower member by dividing the seat back frame into upper and lower members, and the upper member is coupled to the lower member by a hinge shaft so as to be pivotable in the front-rear direction, and in a normal posture when seated on an occupant Elastic means for biasing the seat back frame shape to maintain the state is provided between the upper member and the lower member ;
Furthermore, when an excessive impact load is applied to the seat back frame, a stopper means is provided between the upper member and the lower member for limiting rotational deformation of the upper member with respect to the lower member,
The elastic means and the stopper means are the elastic member and the shaft in a shaft through an elastic member that supports the upper member and the lower member at a position different from the hinge shaft. Sheet. In claim 1,
  The vehicle seat according to claim 1, wherein the elastic member is a rubber bush and the shaft is a bolt.

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