JP4211468B2 - Vehicle seat - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle seat, and more particularly to a vehicle seat equipped with a motor-driven (power type) reclining device.
[0002]
[Prior art]
As a vehicle seat provided with a motor-driven reclining device, for example, there is a technique disclosed in Patent Document 1. In this technology, when the vehicle is driven while the passenger seat back is tilted backward, the motor of the reclining device is automatically driven and controlled, and the seat back can be forcibly returned to the standing state.
[0003]
[Patent Document 1]
Japanese Utility Model Publication No. 5-65659
[Problems to be solved by the invention]
However, since the seat back is returned by the motor of the reclining device, its operating speed is the same as that during normal reclining operation. When this technology is employed to return the seat back that is tilted backward to the normal standing position, for example, in the event of a rear collision of the vehicle, the operating speed of the seat back is considerably slower than the actual required value. Therefore, there is a delay in the timing of supporting the seated person's body by the seat back. In addition, an active headrest or the like having a function of supporting the seated person's head by instantaneously moving the headrest forward and upward at the time of a rear collision of the vehicle may not function normally.
The present invention is intended to solve the conventional problem. Even when the seat back is tilted backward, when the vehicle receives an impact load from the rear, the seat back is instantly supported by the seat back. Is the purpose.
[0005]
[Means for Solving the Problems]
The present invention is for achieving the above object, and is configured as follows.
The invention according to claim 1 is a vehicle seat provided with a motor-driven reclining device, and when receiving an impact load from the rear of the vehicle, the seat back is tilted backward from the normal standing position. In such a state, the reclining device is operated by driving means different from the motor, and the seat back is returned to the normal standing position faster than in the case of driving control of the motor.
The driving means includes a gas generator that instantaneously generates gas when receiving an impact load from the rear of the vehicle, and a turbine that converts fluid energy of the gas generated by the gas generator into mechanical energy. . The reclining device is operated by the driving force of the turbine. Further, the clutch provided in the rotation transmission path from the motor to the reclining device is set based on the pressure of the gas generated by the gas generator .
According to this configuration, when the vehicle receives an impact load from the rear as in a rear collision, the seat back can be quickly returned to the normal standing position. For this reason, a seated person's body can be instantaneously supported by a seat back. Further, since the seat back returns to the normal standing position, the active headrest can be normally operated.
[0006]
Moreover, the seat back can be returned to the normal standing position more quickly by using the gas (gas) instantaneously generated by a gas generator such as an inflator as the driving means.
In addition, as a form of the turbine, there is a rotary type that converts fluid energy such as gas into a rotational force, or a direct acting type that converts fluid energy into a reciprocating force.
[0007]
In addition, by disengaging the clutch provided in the rotation transmission path from the motor to the reclining device, it eliminates the resistance of the motor to the operation of the reclining device when the seat back is returned to the normal standing position by the driving means. it can.
[0008]
The invention according to claim 2 is the vehicle seat according to claim 1 , wherein the turbine converts the fluid energy of the gas generated by the gas generator into rotational force, and The gear that receives the rotational force and transmits the rotational force to the reclining device generates a thrust force along with the rotation, and is configured to disengage the clutch by the thrust force.
As described above, the gear for transmitting the rotational force from the turbine of the driving means to the reclining device also has a function for disengaging the clutch. Therefore, it is easy to set the timing for disengaging the clutch and the reclining. The device periphery can be made compact.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
FIG. 1 is a side view showing an appearance of a vehicle seat. FIG. 2 is an enlarged cross-sectional view in the direction of arrow AA in FIG. 3 is a cross-sectional view in the direction of arrow BB in FIG. As shown in FIG. 1, the configuration of the seat 10 is roughly divided into a seat cushion 11, a seat back 12, and a headrest 13. The lower arm 11b fixed to the rear end of the cushion frame 11a in the seat cushion 11 and the upper arm 12b fixed to the lower end of the back frame 12a in the seat back 12 are coupled by a motor-driven reclining device 20. . By the operation of the reclining device 20, the seat back 12 rotates in the front-rear direction with respect to the seat cushion 11. Thereby, the tilt angle of the seat back 12 is adjusted.
[0011]
The reclining device 20 is of a circular type and includes a drive shaft 21 at the center thereof. The drive shaft 21 includes a reduction gear 22 on the shaft (FIG. 2). The drive shaft 21 is rotationally controlled through the reduction gear 22, whereby the reclining device 20 is operated, and the upper arm 12 b is rotated around the axis of the drive shaft 21 with respect to the lower arm 11 b.
[0012]
A motor 23 (FIG. 2), which is a drive source of the reclining device 20, can rotate the motor shaft 24 in both forward and reverse directions. The rotation of the motor shaft 24 is transmitted to the worm gear 27 through the clutch 26. The rotation of the worm gear 27 is transmitted to the reduction gear 22 of the drive shaft 21 through an intermediate gear (not shown). The motor shaft 24, the clutch 26, and the worm gear 27 are accommodated in a gear housing 25 provided integrally with the motor 23 side. A first gear 37 and a second gear 38 that are always meshed with each other are located in the gear housing 25. Helical gears are used for both the gears 37 and 38, and a thrust force is generated at the time of mutual meshing rotation.
[0013]
The second gear 38 is supported on the shaft portion 27 a of the worm gear 27 and constitutes one element for constituting the clutch 26. That is, the cross-sectional shape of the shaft portion 27a is rectangular (FIG. 3), and the second gear 38 can be transmitted to the shaft portion 27a so as to be able to transmit rotation and can be moved along the axis. Moreover, the second gear 38 is always urged upward by the spring 26a shown in FIG. 2, and the clutch 26 is kept in the connected state in the state of FIG.
[0014]
A drive means 30 different from the motor 23 is provided at a location adjacent to the gear housing 25 of the motor 23. An inflator 31 and a turbine 32 are used for the driving means 30. The inflator 31 generates gas (nitrogen gas) by instantaneously burning the gas generating agent enclosed therein by an ignition device. The inflator 31 corresponds to a gas generator for generating gas (gas) instantaneously in the present invention.
[0015]
The turbine 32 is of a type in which a pair of rotors 34 rotate within the housing 33 (FIG. 3). Both rotors 34 rotate when the gas generated in the inflator 31 is sent into the housing 33. In other words, the turbine 32 is a rotary type, and converts the fluid energy of the gas from the inflator 31 into rotational mechanical energy. Therefore, the gas generator is not limited to the inflator 31 but may be an air cylinder or the like that can send compressed air into the housing 33 of the turbine 32.
[0016]
Synchronous gears 36 that mesh with each other and rotate synchronously are fixed on individual shafts 35 of both rotors 34. A first gear 37 is coaxially fixed to one of the two synchronous gears 36. Therefore, the rotation of the rotor 34 is transmitted to the first gear 37 and the second gear 38 through the synchronous gear 36.
[0017]
FIG. 4 is a side view schematically showing a state of sitting on the seat 10. Now, it is assumed that the seat 10 tilts the seat back 12 backward from the normal standing position as shown in FIG. In this state, when the vehicle receives an impact load of a certain level or more due to a rear collision or the like, an ignition device of the inflator 31 is actuated by an electric signal from an impact detection sensor (not shown) to instantaneously generate gas. This gas causes the rotor 34 of the turbine 32 to rotate with the synchronous gear 36, and the rotation is transmitted to the worm gear 27 through the meshing rotation of the first gear 37 and the second gear 38.
[0018]
Further, the meshing rotation of the gears 37 and 38 at this time generates a thrust force as already described, and the second gear 38 moves downward in FIG. 2 against the elastic force of the spring 26a. As a result, the clutch 26 is disconnected and the motor shaft 24 and the worm gear 27 are disconnected from each other. Therefore, the rotational force by the driving means 30 is transmitted from the worm gear 27 to the reclining device 20 through the reduction gear 22 without receiving rotational resistance from the motor 23. By the operation of the reclining device 20, the seat back 12 can be quickly returned to the normal standing position as shown in FIG. 4B, and the seated person's body can be supported.
In addition, when the impact load is received, the seat back 12 is quickly returned to the normal standing position, so that the airbag operation is not limited to the rear collision of the vehicle, the airbag is activated at the time of the collision, the seat belt is restrained at the time of the front collision, etc. It is possible to effectively perform the safety function.
[0019]
As a means for stopping the seat back 12 at the position shown in FIG. 4B, the reclining device 20 may be stopped when the seat back 12 is in contact with the back of the seat occupant and receives a load. As other means for stopping the seat back 12 at the normal standing position, a lock mechanism or sensor detection is used. The lock mechanism is a means for mechanically locking the operation of the reclining device 20 when the seat back 12 is in a normal standing position. The sensor detection is a means for detecting the rotational position of the seat back 12 or the reclining device 20 and stopping the operation of the reclining device 20 by the driving means 30. When the seat back 12 is in a normal standing position or a tilted position close to the normal standing position, it is electrically controlled so that the ignition device of the inflator 31 does not work even when the vehicle receives an impact load due to a rear collision. Yes.
[0020]
The ignition device of the inflator 31 may react with an electrical signal from the pre-crash sensor before receiving an impact in addition to an electrical signal from the impact detection sensor when the vehicle receives an impact load. It is also possible to install a plurality of inflators 31 in the driving means 30 and change the number of inflators 31 that generate gas according to the tilt angle of the seat back 12 in the state shown in FIG. It is. That is, when the tilt angle of the seat back 12 is large, gas is generated from all the inflators 31 and the driving force of the driving means 30 is strengthened. On the other hand, when the tilt angle of the seat back 12 is small, the number of inflators 31 that generate gas is reduced and the driving force of the driving means 30 is also reduced.
[0021]
The clutch 26 provided between the motor shaft 24 and the worm gear 27 can be blocked by a gas pressure generated from the inflator 31 through a wire cable or a link mechanism. In this case, the rotation of the synchronous gear 36 in the turbine 32 can be directly transmitted to the reduction gear 22. When the clutch 26 is disengaged, the motor-driven reclining device 20 is in a free state in which the lock is released. Therefore, in this case, it is possible to use a spring force acting so as to always return the seat back 12 to the standing position instead of the driving means 30 by the inflator 31 and the turbine 32. However, if there is no such request and the resistance of the motor 23 can be ignored, the clutch 26 may be eliminated.
[Brief description of the drawings]
FIG. 1 is a side view showing the appearance of a vehicle seat. FIG. 2 is an enlarged sectional view in the direction of arrow AA in FIG. 1. FIG. 3 is a sectional view in the direction of arrow BB in FIG. Side view schematically showing the state of the material 【Explanation of symbols】
10 seat 12 seat back 20 reclining device 23 motor 30 driving means 31 inflator (gas generator)
32 Turbine

Claims (2)

A vehicle seat equipped with a motor-driven reclining device, and when the seat back is tilted backward from the normal standing position when receiving an impact load from the rear of the vehicle, the reclining device is Is operated by another drive means, and is configured to return the seat back to the normal standing position faster than in the case of the motor drive control, and when the drive means receives an impact load from the rear of the vehicle, A gas generator for generating gas and a turbine for converting fluid energy of the gas generated by the gas generator into mechanical energy, and configured to operate the reclining device by the driving force of the turbine to generate gas Based on the pressure of the gas generated by the compressor, the clutch provided in the rotation transmission path from the motor to the reclining device is disconnected. The vehicle seat, which is set to so that. The vehicle seat according to claim 1, wherein the turbine is of a type that converts the fluid energy of the gas generated by the gas generator into a rotational force, and receives the rotational force of the turbine to the reclining device. A vehicle seat configured such that a transmission gear generates a thrust force as the gear rotates, and the clutch is disconnected by the thrust force .

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