JP4277637B2 - Headrest device - Google Patents

Description

  The present invention relates to a headrest device that is provided in a vehicle seat and functions to well protect the occupant's neck when the occupant receives a large impact force from the rear to the front of the vehicle.

  In the headrest device that functions to protect the passenger's neck when the vehicle is struck rearward, the headrest body is removed from the gap between the headrest body and the passenger's head using the force that the passenger is strongly pressed against the seat back. There is something to move. In such a headrest device, an operating plate that is moved by the pressing force of the upper body of the occupant is disposed in the seat back, and a lower end portion of a stay that supports the headrest is connected to the operating plate, and an intermediate portion of the stay is further connected to the seat back. It is configured so that it can be rotated. When the operation plate moves to the rear of the seat when the vehicle is bumped, the headrest body protrudes forward of the seat and operates to reduce the distance between the head of the occupant and the headrest body. On the other hand, the operation plate is arranged in a predetermined position away from a member that supports the occupant so that the operation plate does not move during normal use of the seat (see, for example, Patent Document 1). ).

Further, in other methods, during normal use, a position adjustment mechanism that allows the position of the headrest body to be arbitrarily adjusted in the front-rear direction of the seat by an occupant's operation, and further an acceleration that can detect an excessive forward impact applied to the vehicle The detection mechanism is provided in the headrest body. When the acceleration detection mechanism detects an impact acceleration of a predetermined value or more, the lock mechanism of the position adjustment mechanism is automatically released, the headrest body is pushed forward by a spring force, and the pushed position can be maintained. In some cases, the distance between the head of the occupant and the headrest body can be reduced (see, for example, Patent Document 2).
JP 2000-21157 A JP 2000-342379 A

  However, in the conventional technique such as Patent Document 1 described above, since the operation plate is arranged away from the member that supports the occupant in the seat back, there is a delay in the timing at which the headrest body starts moving. In addition, the movement distance of the operating plate is shortened by the distance away, and it is difficult to secure a sufficient movement distance of the headrest body.

  On the other hand, in the conventional technique such as Patent Document 2, since the acceleration detection mechanism is disposed in the headrest body, the impact is transmitted to the acceleration detection mechanism via the seat back. When the rear-end collision occurs, the seat back is also bent, so that the detection of the acceleration detection mechanism is delayed, and the detection accuracy is also lowered. For this reason, in order to obtain a reliable operation, an expensive control device is required, which is expensive.

  In order to solve these problems of the prior art, an object of the present invention is to realize a headrest device that includes an acceleration detection mechanism with a small detection delay and can secure a sufficient amount of movement of the headrest body.

To solve the problems described above, technical first means taken in the present invention supports a headless body portion which is arranged above the seat back of the seat, the headrest body to the seat back stay And when a predetermined load is input from the front surface of the seat back in a state in which a predetermined acceleration or more is applied to the seat in the forward direction, the head support portion constituting the headrest body is placed in front of the seat. In the headrest device configured to expand to the normal position, the head support portion biased in the expansion direction is locked in the normal use position before the expansion, thereby holding the head support portion in the normal use position. on the other hand, a locking mechanism for deploying the head support portion when the locking state is released, swingably rotated in the longitudinal direction of the seat back該Shi Is pivotally supported in the-back, a movement detecting mechanism having a plurality of ratchet teeth to the pitch circle centered on the pivot center to the pivot support base end, the rear when a predetermined acceleration or more forward-facing to the seat back is applied And an acceleration detection mechanism having a ratchet tooth that meshes with the ratchet tooth of the movement detection mechanism when pivotally rotated in the seat back so as to swing freely.
The movement detecting mechanism and the acceleration detecting mechanism operate in cooperation with each other in a meshed state between the ratchet teeth, thereby releasing the locking state of the locking mechanism and deploying the head support portion . That is.

  According to the first aspect of the present invention, the delay in detection and operation can be reduced by accommodating the acceleration detection mechanism and the seated person movement detection mechanism in the seat back, and by operating in conjunction with each other, Malfunction can be avoided.

  The linkage between the acceleration detection mechanism and the seated person movement detection mechanism is achieved by a mechanical method using an engagement member, and can be made inexpensive.

  First, the 1st Example of the headrest apparatus 10 concerning this invention is described using FIGS.

  FIG. 1 shows a seat back 1 of a seat (not shown) provided with a headrest device 10 according to the present invention. In the seat back 1 shown in FIG. 1, only the frame 40 is shown, and illustration of a spring body, a cushion body, and a skin member provided with an actual seat is omitted.

  The frame 40 is a frame having a substantially rectangular shape. The side frames 42 and 43 on both sides, the upper frame 41 on the upper side, and the lower frame 46 on the lower side are assembled and assembled together. Further, a pair of stay holders 44 are fixedly attached to the central portion of the upper frame 41 so as to extend vertically in parallel.

  The headrest device 10 includes a headrest body 20 and a pair of stays 51 extending downward from the lower side of the headrest body 20. The stay 51 is inserted into a guide hole (not shown) provided at the center of a guide member 44 a that is inserted and fixed to the stay holder 44, and the headrest body 20 is supported by the seat back 1. Yes. The guide member 44a has a known configuration that engages with a notch (not shown) provided in the stay 51 to adjust and hold the headrest body 20 at a predetermined height.

  A guide rail 45 is fixedly attached to the upper frame 41 located between the two stay holders 44, and the guide rail 45 extends downward and is disposed within a substantially rectangular shape of the frame 40. And the trigger mechanism 7 mentioned later is attached to the guide rail 45 so that an up-down movement is possible. The trigger mechanism 7 controls the deployment operation of the headrest body 20.

  Next, the configuration of the headrest body 20 will be described with reference to FIGS.

  FIG. 2 shows a normal use state of the headrest body 20, and FIG. 4 shows a developed state in which the head support portion 25 of the headrest body 20 protrudes forward of the seat.

  One base bracket 24 is fixed in the headrest body 20 so as to connect the upper ends of both of the pair of stays 51 that support the headrest body 20 above the seat back 1. The base bracket 24 is a member that ensures the strength of the headrest body 20. A base portion 22, which is a component on the rear side of the headrest body 20, is fixedly attached to the base bracket 24 via a reinforcing body 23. In addition, the head support portion 25 which is a front part is attached to the base bracket 24 via a link mechanism 30.

  The link mechanism 30 is composed of a pair and is disposed on the left and right sides of the base bracket 24. Further, the link mechanism 30 includes a link 31 and a link 32, and the link 31 and the link 32 are coupled to each other by a shaft 33 at a substantially central portion thereof. The upper end of the link 32 is coupled to the base bracket 24 by a rotary shaft 35, and the lower end of the link 31 is slidably attached to a long hole 24a formed in the base bracket 24 so as to extend in the vertical direction. Yes.

  On the other hand, the head support portion 25 includes a support plate 27 disposed inside the headrest body 20, a cushion body 25a disposed to cover the front surface of the support plate 27, and a skin body 25b that further covers the cushion body 25a. The The upper and lower portions of the support plate 27 are provided with flange portions 27a and 27b formed so as to protrude rearward. The upper end of the link 31 is slidably attached to the elongated hole 27c formed in the upper flange portion 27a so as to extend in the vertical direction by the rotary shaft 34. The lower end of the link 32 is rotatably connected to the lower flange portion 27b by a rotary shaft 36.

  As can be seen from the above configuration, the link mechanism 30 constitutes a so-called X link mechanism. Each rotating shaft 34, 35, 36, 37 is configured to extend horizontally in the headrest body 20 so as to connect the link mechanisms 30 on both sides to ensure the rigidity of the link mechanism 30. As shown in FIGS. 6 and 7, a spring 79 is provided between the rotary shafts 34, 36 at the substantially central portion in the length direction of each rotary shaft 34, 35, 36, 37. 37 is attached between the springs 37. The springs 78 and 79 are tension springs, and exert an acting force so as to always open the X link mechanism, that is, to bring the link mechanism 30 into a deployed state. As shown in FIG. 4, the link mechanism 30 has a characteristic as an X link mechanism, and can deploy and operate so that the head support portion 25 protrudes forward while maintaining a substantially parallel posture with respect to the base bracket 24. It can be configured.

  As further shown in FIG. 2, one side of the two stays 51 is used to change from the normal use state of FIG. 2 to the expanded state in which the head support portion 25 shown in FIG. A locking mechanism 50 is provided. The locking mechanism 50 includes an operating wire 52 that is inserted into the hollow portion of the stay 51 and extends. The operating wire 52 includes spherical locking portions 52 a and 52 b at both ends, and the locking portion 52 a at the upper end is coupled to the shaft end portion of the rotating shaft 37. On the other hand, the lower end locking portion 52 b is coupled to the hook 53. 2 and 3, the hook 53 is disposed through a hollow locking sleeve 54 attached to the lower end of the stay 51, and a protrusion 53a formed on the hook 53 is formed at the end thereof. It has a configuration that can be caught. When the hook 53 is hooked on the locking sleeve 54, the operating wire 52 can pull the rotating shaft 37 against the acting force of the springs 78 and 79, and can hold the link mechanism 30 in the normal use state of FIG. ing.

As shown in FIGS. 1 and 8 to 11, the headrest device 10 is provided with a trigger mechanism 7 in the seatback 1 that can release the hooking and locking of the locking sleeve 54 and the hook 53. Yes. The trigger mechanism 7 is attached to a slider 55 that is slidable and vertically movable with respect to a guide rail 45 fixedly attached to the upper frame 41. The slider 55 has a hole 55a into which the guide rail 45 is inserted and a hole 55c into which the stay 51 is inserted. When the stay 51 is inserted and assembled into the hole 55c, the hook 55b provided at the upper end of the hole 55c fits into the notch 51b formed on the outer periphery of the stay 51, and the slider 55 and the stay 51 become one body. The guide rail 45 can be moved. The lower end of the guide rail 45 defines a range of downward movement of the slider 55 to which the stopper 47 is attached.

  A shaft portion 56 extending horizontally in the sheet width direction is formed on the slider 55, and a detection arm 60 (movement detection mechanism) is rotatably attached to the shaft portion 56. The detection arm 60 has an extension 61b that extends in the vertical direction of the seat back 1, and a detection rod 61 that is formed to have a detection end 61a that is bent at the lower end of the extension 61b and extends in the width direction of the seat back 1. The detection rod 61 is composed of an arm base 62 that is coupled to the detection rod 61 and pivotally supported by a shaft portion 56 so that the detection rod 61 swings in the front-rear direction of the seat back 1. The arm base portion 62 has a hole 62b into which the upper end portion of the detection rod 61 is inserted, a shaft hole 62c into which the shaft portion 56 is inserted, and a ratchet tooth including a plurality of teeth with the center of the shaft hole 62c as the center of the pitch circle. 62a is formed. Further, a coil-shaped spring 63 is attached so that one end 63a is engaged with a groove 56a formed in the shaft portion 56, and the other end 63b is engaged with the arm base 62, and the detection end 61a is always attached. It arrange | positions so that it may be extruded to the front direction of the seat back 1. FIG.

  Further, like the detection arm 60, an acceleration detection mechanism 70 that swings in the front-rear direction of the seat back 1 is attached to the slider 55. The acceleration detection mechanism 70 has a configuration in which a weight 75 is rotatably attached to the frame 75 by a pin shaft 73 in the frame 75. A shaft hole 71b into which the pin shaft 73 is inserted is formed in the upper portion of the weight 71, and a ratchet tooth 71a comprising a plurality of teeth with the center of the shaft hole 71b as the center of the pitch circle is formed on the lower end surface. . Further, a spring 72 is attached between the weight 71 and the frame body 75 and urges the weight 71 to rotate forward so as to abut against a wall portion 77 formed on the frame body 75. As will be described later, when a predetermined acceleration or more in the forward direction acts on the seat back 1, the weight 71 swings and rotates backward against the biasing force of the spring 72, and the ratchet teeth 71a and the detection arm 60 are moved. The ratchet teeth 62a provided can be engaged with each other.

  On the other hand, a spring 57 is also attached between the frame body 75 and the slider 55 to urge the frame body 75 to rotate forward. The spring 57 is a tension spring whose both ends are locked to a pin 56 b formed in the slider 55 and a hole 75 b provided in the frame body 75.

  As shown in FIGS. 6 and 7, a deployment position holding mechanism 80 is provided in the headrest body 20. The unfolded position holding mechanism 80 maintains the unfolded state when the headrest body 20 changes from the normal use state illustrated in FIG. 6 to the unfolded state illustrated in FIG. 7, and reinforces the base portion 22 of the headrest body 20. A pole 81 is rotatably attached to the body 23 with a pin 81b. A slide link 82 is attached to the rotary shaft 37 located below and behind the link mechanism 30. A long hole 82a is formed in the slide link 82, and a guide guide pin 83 fixed to the reinforcing body 23 is attached to the long hole 82a.

  In the process of transition to the unfolded state shown in FIG. 7, the rotating shaft 37 moves upward together with the slide link 82 along the long hole 23 a formed in the reinforcing body 23. At this time, since the slide link 82 is guided by the elongated hole 82a extending vertically and the guide pin 83, the slide link 82 is configured to move upward while maintaining the posture extending vertically.

  On the end face of the slide link 82 facing the pole 81, latch teeth 82b made of a plurality of teeth are formed. Further, a tooth 81a that can mesh with the latch tooth 82b is formed at one end of the pole 81, and the pole 81 is rotated so that the tooth 81a meshes with the latch tooth 82b when the unfolded state shown in FIG. A biasing spring 84 is attached between the reinforcing body 23 and the spring 84. By engaging the teeth 81a of the pole 81 with the latch teeth 82b, the link mechanism 30 is maintained in the expanded state even when a large load acts on the head support portion 24.

  Next, the unfolding operation of the headrest device 1 configured as described above will be described in detail with reference to FIGS. 9, 10, and 11.

  FIG. 9 shows a state of the trigger mechanism 7 when the occupant is seated on the seat and performing normal use. In this state, the ratchet teeth 71a of the weight 71 are separated from the ratchet teeth 62a of the detection arm 60. Then, when a cushion body and a suspension spring (not shown) provided in the seat back 1 are bent due to a change in the load applied to the passenger's seat back 1 due to acceleration / deceleration of the vehicle while the occupant is seated, the spring The detection arm 60 supported by 63 is merely swung in the C direction around the shaft portion 56, and the deployment operation of the headrest device 1 is not activated.

  Next, FIG. 10 shows a state of the trigger mechanism 7 when a large impact load is applied from the rear to the front of the vehicle. The vehicle is accelerated forward (leftward in FIG. 10), and the seat fixed to the vehicle floor (not shown) is also pushed forward together with the vehicle. As a result, an inertia force more than a predetermined value acts on the weight 71, the spring 72 (FIG. 8) bends, and the weight 71 rotates counterclockwise in FIG. It rotates until it abuts against the wall 76 provided on the frame 75, and is in a state of meshing with the ratchet teeth 71a and the ratchet teeth 62a.

  At this time, the detection arm 60 is supported by the spring 63, and the frame body 75 is supported by the spring 57, and does not rotate.

  Furthermore, the upper body of the passenger seated on the seat is pressed against the seat back 1 by the vehicle moving forward due to the impact load. As shown in FIG. 11, the detection arm 60 rotates in the direction D shown in the figure by the pressing force of the back of the occupant. By this rotation operation, the weight 71 is in contact with the wall portion 76, so that the frame body 75 rotates integrally with the detection arm 60. A protrusion 78 is provided in a lower portion of the frame body 75. In the process of rotating the frame body 75 from the state of FIG. 10 to the state of FIG. 11, the protrusion 78 has a slit 54b provided in the locking sleeve 54. As a result, it comes into contact with the hook 53 locked to the locking sleeve 54. As a result, the catch of the protrusion 53a of the hook 53 with the locking sleeve 54 is released. When the hook 53 is released, the link mechanism 30 operates so that the X link is opened by the acting force of the springs 78 and 79, and the head support 27 is deployed at a high speed at the position shown in FIG. When the deployment is completed, the deployment position is held by the action of the deployment position holding mechanism 80.

  Next, a trigger mechanism 107 according to a second embodiment of the present invention will be described with reference to FIGS. In the drawing of the second embodiment, the same reference numerals as those in the first embodiment denote the same components.

  A fuse pin 153 having the shape shown in FIG. 14 is coupled to the lower end of the working wire 52. The fuse pin 153 includes a guide portion 153d having a size that fits in the hollow stay 51 at the upper end portion, and has a shape in which the flange portion 153b is engaged with the lower end of the guide portion 153d. A groove 153c is formed in a joint portion between the guide portion 153d and the flange portion 153b, and the diameter of the guide portion 153d is reduced. The outer diameter of the flange portion 153 b is larger than the inner diameter of the stay 51, and the flange portion 153 b is in contact with the lower end of the stay 51 so that the operating wire 52 can be held and placed. A grip portion 153a is formed at the lower end portion of the fuse pin 153 so as to be connected to the flange portion 153b.

  A frame body 175 corresponding to the frame body 75 of the first embodiment is swingably attached to the slider 55. A weight 71 that is urged clockwise in FIG. 12 by a spring (corresponding to the spring 72 shown in FIG. 8) is attached to the frame 175 so as to be swingable. The frame 175 is integrally formed with a hold portion 175a, and the grip portion 153a of the fuse pin 153 is fitted into the hold portion 175a.

  In such a trigger mechanism 107, the detection arm 60 freely swings about the shaft portion 56 during normal use of the seat. On the other hand, if a large impact load in the forward direction acts on the vehicle and the detection arm 60 rotates rearward by the occupant's pressing force with the ratchet teeth 71a and the ratchet teeth 62a engaged as shown in FIG. 153 is cut by a groove 153c. As a result, the catch with the stay 51 at the lower end of the operating wire 52 is released, and the head support 27 is deployed at a high speed at the position shown in FIG.

It is a perspective view which shows the structure of the seat back of a sheet | seat provided with the headrest apparatus which concerns on the 1st example of this invention. It is sectional drawing of the AA part in FIG. 1, and shows a headrest main body when it exists in a normal use state. FIG. 3 is an enlarged view of a lower end portion of the stay shown in FIG. 2. It is sectional drawing of the AA part in FIG. 1, and shows a headrest main body when it exists in an unfolded state. FIG. 5 is an enlarged view of a lower end portion of the stay shown in FIG. 4. It is sectional drawing of the BB part in FIG. 1, and shows a headrest main body when it exists in a normal use state. It is sectional drawing of the BB part in FIG. 1, and shows a headrest main body when it exists in an unfolded state. It is a disassembled perspective view of the trigger mechanism with which the headrest device concerning the present invention is equipped. It is a side view which shows when the headrest apparatus of the trigger mechanism with which the headrest apparatus which concerns on this invention is equipped is in a normal use state. It is a side view which shows a trigger mechanism when an impact acts from the vehicle rear to the front. It is a side view showing a trigger mechanism when an impact acts from the rear to the front of the vehicle and the occupant is pressed against the seat back. It is a side view which shows when the headrest apparatus of the trigger mechanism with which the headrest apparatus which concerns on 2nd Example of this invention is equipped is in a normal use state. It is a side view which shows a trigger mechanism when an impact acts from the vehicle rear to the front. It is a side view of the fuse pin utilized for the headrest device concerning the 2nd example of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Seat back 10 Headrest apparatus 20 Headrest main body 25 Head support part 51 Stay 60 Movement detection mechanism (detection arm)
70 Acceleration detection mechanism

Claims (1)

A headless main body disposed above the seat back of the seat ;
A stay that supports the headrest body on the seat back, and when a predetermined load is input from the front surface of the seat back in a state where a predetermined acceleration or more is applied to the seat in a forward direction, the headrest body In the headrest device configured to expand the head support portion constituting the front of the seat,
When the head support portion biased in the deployment direction is locked at the normal use position before deployment, the head support portion is held at the normal use position, while the locked state is released. A locking mechanism for deploying the head support,
A movement detection mechanism pivotally supported in the seat back so as to be swingable and rotatable in the front-rear direction of the seat back, and having a plurality of ratchet teeth having a pivot center as a center of the pitch circle at the pivot base end;
The ratchet of the movement detection mechanism is pivotally supported in the seat back so as to swing and rotate rearward when an acceleration greater than a predetermined value is applied to the seat back. An acceleration detection mechanism having ratchet teeth that mesh with the teeth,
A headrest device in which the movement detection mechanism and the acceleration detection mechanism operate in cooperation in a meshed state between the ratchet teeth, thereby releasing the locking state of the locking mechanism and deploying the head support portion .

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