JP2011025782A - Active headrest - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an active headrest unlocking a lock mechanism by a small operation load even in a structure in which the lock mechanism is unlocked when a rear end collision occurs on a vehicle, an energizing force of an extension spring is applied accompanying the unlocking, a link mechanism acts, and a support member thereby pops out relative to a base member and receives the back of a head of an occupant. <P>SOLUTION: The active head rest 3 includes the lock mechanism R retaining the support member 24 in a state before popping out relative to the base member 20 resisting the energizing force of the extension spring 60. The lock mechanism R is composed of two link bars 70, 72. When the rear end collision occurs on the vehicle, the two link bars 70, 72 turn over from a generally dog leg shape resisting the energizing force of the extension spring 60 by an inertia force applied accompanying the rear end collision, thereafter move to a generally reverse dog leg shape by the energizing force of the extension spring 60, and thereby the lock mechanism R is switched from a locked state to an unlocked state. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an active headrest. More specifically, when a rear collision occurs in a vehicle, the lock mechanism is unlocked, and the urging force of a tension spring acts along with the lock release, so that the link mechanism operates. The present invention relates to an active headrest in which a support member jumps out of a base member and receives an occupant's rear head.

  2. Description of the Related Art Conventionally, when a rear collision occurs in a vehicle, a headrest that so-called an active headrest, in which a support member jumps out of a base member and receives an occupant's rear head, is already known. Here, in Patent Document 1 below, when a rear collision occurs in the vehicle, the lock mechanism is unlocked, and the urging force of the tension spring acts along with the lock release, so that the link mechanism operates to support the support. A headrest having a structure in which a member (a movable part on the front side of the headrest) protrudes from a base member (a fixed part on the rear side of the headrest) to receive the occupant's rear head is disclosed. As a result, the occupant's back head can be instantly received by the support member, so that even if a rear collision occurs in the vehicle, the occupant can be prevented from whipping, and the safety of the occupant can be improved.

JP 2002-142910 A

  However, in the above-described technology, the lock mechanism is unlocked by operating the release lever against the urging force of the tension spring by a trigger device that generates an operation load. When the release lever is operated, the direction in which the operation load from the trigger device acts is substantially opposite to the direction in which the biasing force of the tension spring acts on the release lever, so the operation load from the trigger device is gradually increased. As a result, a trigger device having a large capacity has been required.

  An object of the present invention is to solve such problems. The purpose of the present invention is to release the lock mechanism when a rear collision occurs in the vehicle, and the urging force of the tension spring acts upon the lock release. By providing an active headrest that can unlock the lock mechanism with a small operation load even when the link mechanism is activated and the support member jumps out of the base member and receives the rear head of the occupant. is there.

The present invention is for achieving the above object, and is configured as follows.
According to the first aspect of the present invention, there is provided a base member assembled on the seat back side, a support member assembled to the base member via a link mechanism, and the support member against the biasing force of the tension spring. And a lock mechanism that holds the member in a normal state before it jumps out.When a rear collision occurs in the vehicle, the lock mechanism is unlocked, and the urging force of the tension spring acts as the lock is released. An active headrest that activates the link mechanism and the support member jumps out of the base member to receive the rear head of the occupant. The lock mechanism includes a first link bar and a second link bar. The base end of the first link rod is pivotally attached to the base member side to which one end of the tension spring is hooked, and the base end of the second link rod is the other end of the tension spring. The ends of the first link bar and the second link bar are pivotally attached to each other, and at least one of the link bars is attached to at least one of the link bars. When the front ends interfere with each other, a stopper is provided to hold the support member in a normal state before it jumps out of the base member against the urging force of the tension spring. The lock mechanism is locked by the two link rods being held in a generally square shape by the stopper while resisting the urging force of the tension spring. As a result of the inertial load acting on the two link rods, the two link rods turn over from the substantially square shape against the urging force of the tension spring, and eventually become almost inverted by the urging force of the tension spring. By operating The lock mechanism is characterized in that it switched from the locked state to the unlocked state.
According to this configuration, the lock mechanism can be unlocked by turning over both link bars by the inertial load acting on both link bars when a rear collision occurs in the vehicle. At this time, the direction of the inertial load acting on both link rods (front to rear direction) and the direction in which the urging force of the tension spring acts on the second link rod (from bottom to top) are substantially intersected. Without requiring an inertia load, the lock mechanism can be unlocked by turning over both link rods. Therefore, as explained in the prior art, there is no need to gradually increase the operation load from the trigger device (in the embodiment, the inertial load acting on both link bars 70 and 72 is gradually increased). The lock mechanism can be unlocked with a small inertia load.

Further, the invention according to claim 2 is the active headrest according to claim 1, wherein at least one of the tip ends of the two link rods has both link rods when a rear collision occurs in the vehicle. A weight is provided to increase the acting inertia load.
According to this configuration, it is possible to increase the inertial load acting on both link rods when a rear collision occurs in the vehicle. Therefore, even if the inertial load acting on both link rods is small, the lock mechanism can be reliably unlocked.

The invention according to claim 3 is the active headrest according to any one of claims 1 to 2, wherein the support member has two links when a rear collision occurs in the vehicle, An urging means is provided that operates in a direction to turn over against the urging force of the tension spring from a substantially square shape.
According to this configuration, since the urging means is provided, when a rear collision occurs in the vehicle, the two link rods are operated from a substantially square shape in a direction to turn over against the urging force of the tension spring. be able to. Therefore, even if the inertia load acting on both link rods is small, the lock mechanism can be unlocked more reliably.

FIG. 1 is an exploded perspective view of an active headrest according to an embodiment of the present invention. FIG. 2 is a schematic side view of the active headrest shown in FIG. 1 in the assembled state, and shows a normal state before a rear collision occurs in the vehicle. FIG. 3 shows a state in which a rear collision has occurred in the vehicle from the state shown in FIG. 2 and the lock mechanism has started to unlock. FIG. 4 shows a state where both link rods of the lock mechanism are turned over from the state shown in FIG. FIG. 5 shows a state in which the unlocking of the lock mechanism is completed and the support member is popped out from the state shown in FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to FIGS. In each of the above-described drawings, in order to show the inside of the active headrest 3 in an easy-to-understand manner, the cushion structure and the skin structure are omitted, and only the internal frame structure is shown. In the following description, “up”, “down”, “front”, “back”, “left”, and “right” refer to the directions of “up”, “down”, “front”, “back”, “left”, and “right” described in the above-described drawings. The direction of up, down, front, back, left and right is shown.

  First, the structure of the active headrest 3 according to the embodiment of the present invention will be described with reference to FIGS. The active headrest 3 is mainly composed of a base member 20 assembled to a seat back (not shown) via a pair of left and right stays 22 and 22 (not shown in FIG. 1), and a three-bar link to the base member 20 A support member 24 assembled via the mechanism L, and a lock that holds the support member 24 in a normal state that is substantially integral with the base member 20 against the urging force of the pair of left and right first tension springs 60, 60. And mechanism R. Below, the detailed structure of the support member 24 and the lock mechanism R is demonstrated among these structural members.

  First, the support member 24 will be described. This support member 24 is a substantially cover-like member formed so as to be able to receive the rear head of the passenger. The support member 24 is assembled to the front side of the base member 20 via the three-bar linkage mechanism L as described above. Here, the three-joint link mechanism L will be described in detail. The three-joint link mechanism L includes a connecting arm 30 formed in a thick plate shape and ribs 24 a and 24 a formed on the left and right of the rear surface of the support member 24. Has been.

  Both sides in the width direction on one end side (upper side in FIG. 1) of the connecting arm 30 are pivotally connected to the upper sides of ribs 21 and 21 formed on the left and right sides of the base member 20 via pins P1, respectively. On the contrary, both sides in the width direction on the other end side (the lower side in FIG. 1) of the connecting arm 30 are pivotally attached to the upper sides of the left and right ribs 24a, 24a of the support member 24 via pins P2. ing.

  Further, a pin P3 is fixed to the lower side of the ribs 24a of the support member 24 so as to bridge the left and right sides. At this time, the pin P3 is fixed in a state of being inserted into the long holes 20a and 20a formed in both the ribs 21 of the base member 20. Further, the pair of left and right first tension springs 60, 60 described above are hooked between the pin P1 and the pin P3, respectively.

  Thereby, when the pin P3 is moved from the lower end side of both the long holes 20a toward the upper end side by the urging force of the two tension springs 60, the three-joint link mechanism L is operated to move the support member 24 from the normal state. It is possible to switch to a protruding state that protrudes from the base member 20. In this protruding state, the support member 24 has a structure capable of receiving the occupant's rear head. The three-bar linkage mechanism L is configured in this way.

  As shown in FIG. 2, when the support member 24 is in the normal state, the surface of the connecting arm 30 facing the base member 20 (the rear surface of the connecting arm 30 in FIG. 2) is ratchet in the width direction. 40 is integrally formed. The ratchet 40 is formed with three steps 42a, 42b, and 42c along the outer peripheral surface 42 thereof. On the other hand, a stopper 50 that can be engaged with these three steps 42a, 42b, and 42c is pivotally attached to the base member 20 via a pin P4.

  A hook 54 is formed on the lower surface of the stopper 50. A second tension spring 58 is latched between the hook 54 and the arm 20 c formed on the base member 20. Thereby, the front-end | tip 52 of the stopper 50 can be hold | maintained in the state pressed on the outer peripheral surface 42 of the ratchet 40. FIG.

  A solenoid 80 is provided on the rear surface of the support member 24. The solenoid 80 is electrically connected to an ECU (not shown) that detects that a rear collision has occurred in the vehicle. When the solenoid 80 receives a signal indicating the occurrence of a rear collision from the ECU, the iron core 82 protrudes rearward from the inside thereof with its own excitation. The solenoid 80 is provided such that when the support member 24 is in a normal state, the protruding iron core 82 can press the tips of both link bars 70 and 72. The solenoid 80 corresponds to “biasing means” described in the claims.

  Next, the lock mechanism R will be described. The lock mechanism R is composed of a first link bar 70 and a second link bar 72. The base end of the first link rod 70 is pivotally attached to the pin P1. On the other hand, the base end of the second link rod 72 is also pivotally attached to the pin P3. The tip ends of both link bars 70 and 72 are pivoted to each other via a pin P5.

  A stopper 72 a is formed at the tip of the second link bar 72. The stopper 72a is a member for causing the link rods 70 and 72 to play the role of rods against the pins P1 and P3. Accordingly, both link bars 70 and 72 can be held in a substantially square shape against the urging force of the first tension spring 60, so that the pin P3 is positioned slightly before the lower ends in both the long holes 20a. (See FIG. 2).

  A weight 74 is provided at the tip of the second link bar 72. Thereby, the inertial load which acts on both the link rods 70 and 72 when the rear collision occurs in the vehicle can be increased.

  Subsequently, the operation of the active headrest 3 having the above-described configuration will be described with reference to FIGS. First, an operation in which the support member 24 switches from the normal state to the protruding state will be described. As described above, the normal state is a state in which the support member 24 is held so as to be substantially integrated with the base member 20 (see FIG. 2). This holding is performed by holding both link bars 70 and 72 in a substantially square shape against the urging force of the first tension spring 60 in the lock mechanism R described above. This holding corresponds to the locked state of the lock mechanism R.

  When a rear collision occurs in the vehicle from this normal state, the lock mechanism R is unlocked. This unlocking is performed by an inertial load acting on both link rods 70 and 72 when a rear collision occurs in the vehicle. When this inertial load is applied, the link rods 70 and 72 turn over from the substantially square shape against the urging force of the first tension spring 60 (the pin P5 connects the pin P1 and the pin P3). Both link rods 70 and 72 operate so as to cross the line).

  At this time, as already described, the inertial load acting on both link bars 70, 72 is increased by the weight 74, so that the turnover operation of both link bars 70, 72 can be assisted. At this time, as already described, since the iron core 82 of the solenoid 80 presses the tip ends of both link bars 70 and 72, this also assists the turnover operation of both link bars 70 and 72. Yes (see FIG. 3). With this turnover, the pin P3 moves from a position slightly before the lower end in both the long holes 20a to the lower end (see FIG. 4).

  Eventually, when the turnover is completed, both link bars 70 and 72 are actuated into a substantially inverted letter shape by the urging force of the first tension spring 60. At this time, the pin P3 moves from the lower end to the upper end in both the long holes 20a (see FIG. 5). Thereby, since the support member 24 switches to the protruding state with respect to the base member 20 by the operation of the three-link mechanism L, the occupant's rear head can be instantaneously received by the protruding support member 24. Therefore, even if a rear collision occurs in the vehicle, it is possible to prevent the occupant from becoming whipping, and to increase the safety of the occupant. When the lock mechanism R is unlocked in this way, the support member 24 can be switched from the normal state to the protruding state.

  Next, the operation of returning the protruding support member 24 to the normal state will be described. First, while pushing the base end 56 of the stopper 50 in the direction opposite to the direction in which the biasing force of the second tension spring 58 acts, the engagement state between the tip 52 of the stopper 50 and the steps 42a, 42b, 42c of the ratchet 40 is canceled. Let In this canceled state, the support member 24 is pushed back, and both link bars 70 and 72 are operated so as to be the reverse of the above-described operation.

  Then, the link rods 70 and 72 are returned to a substantially square shape, so that the lock mechanism R is also returned to the locked state, and the support member 24 is also returned to the normal state. In this way, the support member 24 can be returned from the protruding state to the normal state.

  The active headrest 3 according to the embodiment of the present invention is configured as described above. According to this configuration, the lock mechanism R can be unlocked by turning over both link bars 70 and 72 by the inertial load acting on both link bars 70 and 72 when a rear collision occurs in the vehicle. At this time, the direction of the inertial load acting on the link rods 70 and 72 (front to rear direction) and the direction in which the urging force of the tension springs 60 acts on the second link rod 72 (downward to upward) are determined. Since they substantially intersect, the lock mechanism R can be unlocked by turning over both link bars 70 and 72 without requiring a large inertia load. Therefore, as explained in the prior art, there is no need to gradually increase the operation load from the trigger device (in the embodiment, the inertial load acting on both link bars 70 and 72 is gradually increased). The lock mechanism R can be unlocked with a small inertia load.

  Further, according to this configuration, since the weight 74 is provided, it is possible to increase the inertial load acting on both the link rods 70 and 72 when a rear collision occurs in the vehicle. Therefore, even if the inertial load acting on both link bars 70 and 72 is small, the lock mechanism R can be unlocked reliably.

  Further, according to this configuration, since the solenoid 80 is provided, when a rear collision occurs in the vehicle, the link rods 70 and 72 are made to resist the urging force of the first tension spring 60 from the substantially square shape. Can be operated in the direction of turning over. Therefore, even if the inertial load acting on both link rods 70 and 72 is small, the lock mechanism R can be unlocked more reliably.

The contents described above are only related to one embodiment of the present invention, and do not mean that the present invention is limited to the above contents.
In the embodiment, the configuration in which the stopper 72a and the weight 74 are provided at the tip of the second link rod 72 has been described as an example. However, the present invention is not limited to this. For example, a stopper and a weight may be provided at the tip of the first link rod 70.

3 Active headrest 20 Base member 24 Bearing member 60 First tension spring (tensile spring)
70 First link bar 72 Second link bar 72a Stopper 74 Weight L Three-bar link mechanism (link mechanism)
R lock mechanism

Claims (3)

A base member assembled on the seat back side, a support member assembled to the base member via a link mechanism, and the support member in a normal state before jumping out of the base member against the biasing force of the tension spring The lock mechanism is unlocked when a rear collision occurs in the vehicle, and the urging force of the tension spring acts along with the lock release, so that the link mechanism operates and the support member An active headrest that jumps out of the base member and receives the back of the occupant,
The lock mechanism is composed of a first link bar and a second link bar,
The base end of the first link rod is pivotally attached to the base member side to which one end of the tension spring is latched,
The base end of the second link rod is pivotally attached to the support member side to which the other end of the tension spring is latched,
Both ends of the first link bar and the second link bar are pivotally attached to each other,
At least one of the link rods has a stopper that holds the support member in a normal state before it jumps out of the base member against the urging force of the tension spring because the distal ends of the link rods interfere with each other. Provided,
The lock mechanism is in a locked state because the two link rods are held in a generally square shape by the stopper against the urging force of the tension spring at the normal time before the rear collision occurs in the vehicle. ,
When a rear collision occurs in the vehicle, the two link rods turn over against the urging force of the tension spring from a substantially square shape due to the inertial load acting along with the collision, and eventually the tension spring An active headrest characterized in that the lock mechanism is switched from a locked state to an unlocked state by operating in an approximately reverse shape by an urging force. The active headrest according to claim 1,
An active headrest characterized in that at least one of the tip ends of the two link rods is provided with a weight for increasing an inertial load acting on both link rods when a rear collision occurs in the vehicle. The active headrest according to any one of claims 1 and 2,
The support member is provided with an urging means for operating the two links in a direction to turn over against the urging force of the tension spring from a substantially square shape when a rear collision occurs in the vehicle. Active headrest featuring

Images