Abstract: A pipeline includes a pipeline body in which fluid flows and a throttle formed at a specific position of the pipeline body as a flow passage sectional shape of the pipeline body is changed from that of a remaining portion of the pipeline body. The specific position at which the throttle is provided is a position in the pipeline body and corresponds to a position that serves as an abdominal part of the pipeline in a vibration mode where a resonance frequency is the closest to a pulsation frequency of pressure pulsation caused by the fluid.

Abstract: A pipeline includes a pipeline body in which fluid flows and a throttle formed at a specific position of the pipeline body as a flow passage sectional shape of the pipeline body is changed from that of a remaining portion of the pipeline body. The specific position at which the throttle is provided is a position in the pipeline body and corresponds to a position that serves as an abdominal part of the pipeline in a vibration mode where a resonance frequency is the closest to a pulsation frequency of pressure pulsation caused by the fluid.

Abstract: A vehicle seat capable, with a simple, lightweight structure, of improving a whiplash moderation effect from a head rest. In the vehicle seat (10), when there is an impact at a rear face of the vehicle, a support frame (50) that is fixed to a reclining rod (46) separately from a seatback frame (32) supports the waist area of a seat occupant from the vehicle rearward side. Thus, a load from the seat occupant that is inputted to the seatback frame (32) is reduced. Therefore, a displacement amount (deformation amount) of the seatback frame (32) to the vehicle rearward side may be suppressed. Thus, a duration until the head area of the seat occupant abuts against a headrest (16) may be shortened. Moreover, the support frame (32) that only supports the waist area of the seat occupant need only be fixed to the reclining rod (46). Therefore, a simple, lightweight structure may be formed.

Abstract: A vehicle seat (10) is equipped with a seat frame composed of a sub-frame (16) and a rod (30) provided between certain regions of the sub-frame. The rod is equipped with a minor vibration damping portion (34) that maintains rigidity of the seat frame when the seat frame is displaced by a large amount and suppresses an increase in rigidity of the seat frame when the seat frame is displaced by a small amount to reduce the level of minor vibrations in the vehicle seat.

Abstract: A headrest with a function of a dynamic damper that damps vibrations of a vehicle seat, and provide the headrest with an impact absorbing function with respect to a head portion of a seated vehicle occupant. A stay of a headrest is held at a seat back, and a cover, that covers at least a portion of the stay, is supported at the stay so as to be swingable in a seat front-rear direction around a seat transverse direction. Due to a torsion coil spring (an elastic member) elastically deforming when the cover swings, restoring force in a direction opposing a swinging direction of the cover is generated. Further, displacement other than in the swinging direction is suppressed by a suppressing portion that is provided between the stay and the cover.

Abstract: A vehicle seat configured in such a manner that vibration occurring in the seat body can be suppressed without adding a special device such as a dynamic damper. A vehicle seat is configured in such a manner that an upper rail (26) connected to the seat body is slidably supported by a lower rail (28), which is affixed to the vehicle body side, through a pair of slide guides (42, 44) disposed next to each other in the front-rear direction of the seat. The distance (L) between the slide guides (42, 44) is set to be less than the half of the maximum slide amount (S) of the upper rail (26) relative to the lower rail (28). As a result of the configuration, the rigidity of support of the seat body by the vehicle body is reduced to reduce the resonance frequency of the seat body in the front-rear direction. This enables the resonance frequency of the seat body in the front-rear direction to be shifted from the resonance frequency of the vehicle body when the engine of the vehicle is idling.

Abstract: A headrest can be rotated with respect to a seatback, and support strength in a vertical direction of the headrest can be improved. In a vehicular seat, lower side curved surfaces of headrest supports, to which leg portions of a headrest are coupled, slide on lower ends of support brackets and upper side curved surfaces of the headrest supports slide on upper ends of the support brackets, whereby rotation of the headrest supports about an axis along a horizontal direction of a seatback with respect to the support brackets is guided. Further, the lower side curved surfaces touch the lower ends of the support brackets and the upper side curved surfaces touch the upper ends of the support brackets, whereby movement of the headrest supports in a vertical direction of the seatback with respect to the support brackets is suppressed.

Abstract: A headrest with a function of a dynamic damper that damps vibrations of a vehicle seat, and provide the headrest with an impact absorbing function with respect to a head portion of a seated vehicle occupant. A stay of a headrest is held at a seat back, and a cover, that covers at least a portion of the stay, is supported at the stay so as to be swingable in a seat front-rear direction around a seat transverse direction. Due to a torsion coil spring (an elastic member) elastically deforming when the cover swings, restoring force in a direction opposing a swinging direction of the cover is generated. Further, displacement other than in the swinging direction is suppressed by a suppressing portion that is provided between the stay and the cover.

Abstract: A vehicular seat capable of effectively mitigating lateral direction vibrations is provided. In the present vehicular seat (10), a pair of leg portions (32A) of a headrest frame (32) are coupled to a seatback frame (20) to be relatively turnable about a longitudinal direction axis of a seatback (18). Joint portions 32C are provided between the pair of leg portions (32A) and a middle portion (32B) of the headrest frame (32). Thus, the headrest (14) is made turnable to left and right with respect to the seatback (18). Furthermore, the headrest (14) is urged toward a middle position of the range of turning with respect to the seatback (18) by rubber members that are provided between a headrest support (24) and a support bracket (20C). Thus, when lateral direction vibrations are applied to the present vehicular seat (10), the headrest (14) functions as a dynamic damper.

Abstract: A vehicle seat configured in such a manner that vibration occurring in the seat body can be suppressed without adding a special device such as a dynamic damper. A vehicle seat is configured in such a manner that an upper rail (26) connected to the seat body is slidably supported by a lower rail (28), which is affixed to the vehicle body side, through a pair of slide guides (42, 44) disposed next to each other in the front-rear direction of the seat. The distance (L) between the slide guides (42, 44) is set to be less than the half of the maximum slide amount (S) of the upper rail (26) relative to the lower rail (28). As a result of the configuration, the rigidity of support of the seat body by the vehicle body is reduced to reduce the resonance frequency of the seat body in the front-rear direction. This enables the resonance frequency of the seat body in the front-rear direction to be shifted from the resonance frequency of the vehicle body when the engine of the vehicle is idling.

Abstract: A headrest can be rotated with respect to a seatback, and support strength in a vertical direction of the headrest can be improved. In a vehicular seat, lower side curved surfaces of headrest supports, to which leg portions of a headrest are coupled, slide on lower ends of support brackets and upper side curved surfaces of the headrest supports slide on upper ends of the support brackets, whereby rotation of the headrest supports about an axis along a horizontal direction of a seatback with respect to the support brackets is guided. Further, the lower side curved surfaces touch the lower ends of the support brackets and the upper side curved surfaces touch the upper ends of the support brackets, whereby movement of the headrest supports in a vertical direction of the seatback respect to the support brackets is suppressed.

Abstract: A vehicular seat capable of effectively mitigating lateral direction vibrations is provided. In the present vehicular seat (10), a pair of leg portions (32A) of a headrest frame (32) are coupled to a seatback frame (20) to be relatively turnable about a longitudinal direction axis of a seatback (18). Joint portions 32C are provided between the pair of leg portions (32A) and a middle portion (32B) of the headrest frame (32). Thus, the headrest (14) is made turnable to left and right with respect to the seatback (18). Furthermore, the headrest (14) is urged toward a middle position of the range of turning with respect to the seatback (18) by rubber members that are provided between a headrest support (24) and a support bracket (20C). Thus, when lateral direction vibrations are applied to the present vehicular seat (10), the headrest (14) functions as a dynamic damper.

Abstract: A vehicle seat capable, with a simple, lightweight structure, of improving a whiplash moderation effect from a head rest. In the vehicle seat (10), when there is an impact at a rear face of the vehicle, a support frame (50) that is fixed to a reclining rod (46) separately from a seatback frame (32) supports the waist area of a seat occupant from the vehicle rearward side. Thus, a load from the seat occupant that is inputted to the seatback frame (32) is reduced. Therefore, a displacement amount (deformation amount) of the seatback frame (32) to the vehicle rearward side may be suppressed. Thus, a duration until the head area of the seat occupant abuts against a headrest (16) may be shortened. Moreover, the support frame (32) that only supports the waist area of the seat occupant need only be fixed to the reclining rod (46). Therefore, a simple, lightweight structure may be formed.

Abstract: A vehicle seat (10) is equipped with a seat frame composed of a sub-frame (16) and a rod (30) provided between certain regions of the sub-frame. The rod is equipped with a minor vibration damping portion (34) that maintains rigidity of the seat frame when the seat frame is displaced by a large amount and suppresses an increase in rigidity of the seat frame when the seat frame is displaced by a small amount to reduce the level of minor vibrations in the vehicle seat.