Air bag device for vehicle

The present invention relates to a vehicle airbag device, and more particularly to a vehicle airbag device that expands and deploys an airbag by a rotating fan.

In recent years, airbag devices have become widespread in automobiles such as passenger cars. The airbag device expands and deploys the airbag in the event of a vehicle collision to alleviate the impact on occupants and pedestrians and protect them. Since it is necessary to expand and deploy the airbag instantly, an inflator type airbag device that explodes explosives is generally adopted.

By the way, since the inflator type airbag device explodes the explosive as described above, it is difficult to use it repeatedly once it is operated. Therefore, when the airbag expands and expands, it is necessary to replace the entire airbag device even if the vehicle body is not significantly damaged.

On the other hand, Patent Document 1 discloses a technique of an airbag that repeatedly expands and contracts. According to this technique, air is sent to and exhausted from the airbag by using an electric fan that can rotate in the forward and reverse directions. However, this technique inflates the airbag in advance when the occupant gets on board, and does not inflate and deploy the airbag in the event of a collision.

<patcit num="1"><text>Jitsukaisho 55-1457948</text></patcit>

<p> Here, it is considered that if the airbag is expanded and deployed at the time of a collision by using an electric fan instead of the inflator type, the airbag device can be used repeatedly. For that purpose, it is necessary to increase the ventilation capacity of the electric fan so that the airbag expands and expands sufficiently instantly. However, it is difficult to sharply increase the rotation speed of the electric fan due to the inertial resistance of the rotating portion of the electric fan. Therefore, it is difficult to sufficiently expand and deploy the airbag in a short time only by using the electric fan as it is.</p><p> Therefore, an object of the present invention is to provide a vehicle airbag device that can expand and deploy an airbag in a short time and can be used repeatedly.</p>

<p> In order to achieve the above object, the vehicle airbag device of the present invention includes an airbag that expands and deploys at the time of a collision or collision prediction, and a rotating fan that supplies air to the airbag to expand and deploy the airbag. It is characterized by having a rotation driving means for rotating a rotary fan and a rotation speed increasing means for increasing the rotation speed of the rotary fan by operating for a predetermined time from the start of operation of the rotary driving means.</p><p> According to the vehicle airbag device of the present invention configured in this way, the rotational speed of the rotating fan is accelerated for a predetermined time from the start of expansion and deployment of the airbag by the rotational acceleration means, so that the airbag is expanded in a short time. Can be deployed. Further, in the present invention, since the airbag is expanded and deployed by using a rotating fan, the airbag device can be used repeatedly unlike the inflator type that explodes the explosive. The once expanded and expanded airbag may be pushed by hand to contract it, but it can be easily exhausted by rotating the rotating fan in the reverse direction.</p><p> Further, in the present invention, preferably, the rotation speed increasing means increases the rotation speed of the rotating fan so that the rotation speed of the rotating fan reaches a rotation speed exceeding the rotation speed at the time of steady rotation by the rotation driving means. It is composed of. As a result, the airbag can be expanded and deployed in a shorter time.</p><p> Further, in the present invention, preferably, the rotation speed increasing means is a mechanical rotation speed increasing means for mechanically increasing the rotation speed of the rotating fan.</p><p> Further, in the present invention, preferably, the mechanical rotation speed increasing means includes a spring shaft capable of transmitting power to the fan shaft of the rotating fan, and a mainspring spring wound around the spring shaft. As a result, in addition to the power generated by the rotary drive means, the power generated by the spring can be applied to the rotary fan.</p><p> Further, in the present invention, preferably, the mechanical rotation speed increasing speed means further has a clutch mechanism for connecting the spring shaft and the fan shaft, and the clutch mechanism is after a predetermined time has elapsed from the start of operation of the rotation driving means. Separate the spring shaft and fan shaft. By providing the clutch mechanism in this way, the power of the mainspring spring can be selectively applied to the rotating fan for a predetermined time. As a result, the clutch mechanism can be disengaged before the mainspring spring wound around the spring shaft is released and the rotational force of the spring shaft is reduced. As a result, it is possible to prevent the unwound spring from hindering the rotation of the rotating fan.</p><p> Further, in the present invention, preferably, the rotation driving means rotates the spring shaft in the reverse direction after the airbag expands and expands, and rewinds the mainspring spring around the spring shaft. As a result, the unwound spring can be easily rewound. Therefore, the airbag device can be easily and repeatedly used.</p><p> Further, in the present invention, preferably, the rotation driving means is an electric motor, and the rotation speed increasing means is an electric rotation speed increasing means for electrically increasing the rotation speed of the electric motor.</p><p> Further, in the present invention, preferably, the electric rotation speed increasing means causes the electric motor to have an overvoltage and / or an overvoltage exceeding the rated voltage and / or the rated current of the electric motor for a predetermined time from the start of expansion and deployment of the airbag. This is a power supply unit that applies current. As a result, the rotational force of the electric motor can be temporarily increased, and the rotation speed of the rotating fan can be rapidly increased. If a voltage or current exceeding the rating is continuously applied to the electric motor, it is generally expected that the electric motor will generate heat and the electric motor will break down. However, in the present invention, since the time for applying a voltage or the like exceeding the rating to the electric motor is short, the risk of failure of the electric motor is low.</p>

<p> As described above, according to the vehicle airbag device of the present invention, the airbag can be expanded and deployed in a short time and can be used repeatedly.</p>

Hereinafter, the first embodiment of the vehicle airbag device of the present invention will be described with reference to the accompanying drawings. First, FIG. 1 shows an arrangement example of various vehicle airbag devices mounted on a passenger car. FIG. 1 shows an example in which a driver's seat airbag device 100, a passenger seat airbag device 100a, a window airbag device 100b, and a bumper airbag device 100c are mounted on a passenger car. Each airbag device is composed of airbags 1, 1a, 1b and 1c, and actuating parts 10, 10a, 10b and 10c that expand and deploy each of the airbags at the time of collision or collision prediction, respectively. In FIG. 1, each of the driver airbag 1, passenger airbag 1a, window airbag 1b, and bumper airbag 1c is shown by virtual lines in an expanded and expanded state.

Further, in the example shown in FIG. 1, the collision detection unit 7 is arranged inside the central portion of the instrument panel 103, and the collision prediction unit 8 is arranged at the central portion of the front end of the vehicle body 105 of the passenger car. The collision detection unit 7 is, for example, an acceleration sensor, and the collision prediction unit 8 is, for example, a radar or an infrared sensor, and any suitable conventional technology can be used.

Next, the configuration of the vehicle airbag device of the present embodiment will be described with reference to FIG. Here, among the vehicle airbags shown in FIG. 1, the driver airbag device 100 will be described as a representative. The configurations of the operating portions 10a, 10b and 10c of the vehicle airbags 100a, 100b and 100c shown in FIG. 1 are also the same as the configurations of the operating portions 10 of the driver airbag device 100.

As shown in FIG. 2, the airbag device 100 of the present embodiment includes an airbag 1 and an operating unit 10, and the operating unit 10 supplies air to the airbag 1 in order to expand and deploy the airbag 1. It has a rotary fan 2 for rotating, an electric motor (blower fan motor) 3 for rotating the rotary fan 2, and a mechanical rotation speed increasing unit 4.

The operation of the electric motor 3 and the mechanical rotation speed increasing unit 4 is controlled by the CPU 6. When the collision detection unit 7 or the collision prediction unit 8 detects or predicts a collision, the CPU 6 operates the electric motor 3 and operates the mechanical rotation speed increasing unit 4 for a predetermined time from the start of operation of the electric motor 3. Let me. The power of the electric motor 3 is transmitted to the fan shout 20 via the motor shaft 30 and the gear mechanism 5, and rotates the rotary fan 2. Further, the mechanical rotation speed increasing unit 4 operates for a predetermined time from the start of operation of the electric motor 3 to mechanically increase the rotation speed of the rotating fan 2.

Subsequently, the configuration of the mechanical rotation speed increasing unit 4 will be described with reference to FIG. As shown in FIG. 3, the mechanical rotation speed increasing unit 4 includes a spring shaft 40 capable of transmitting power to the fan shaft 20 of the rotating fan 2 and a spring 41 spring having one end wound around the spring shaft 40. Have. The other end of the spring is fixed to the case 44 shown by the virtual line in FIG.

Further, the mechanical rotation speed increasing speed portion 4 further includes a clutch mechanism 42 for connecting the spring shaft 40 and the fan shaft 20, and a lock mechanism 43 for locking the spring shaft 40. The clutch mechanism 42 is an electromagnetic clutch mechanism having a built-in electromagnetic coil, and the connection and disconnection are controlled by the CPU 6. Further, the lock mechanism 43 is composed of a pin inserted into a hole opened perpendicular to the axis of the spring shaft 40 and an electromagnetic solenoid that moves the pin back and forth. The electromagnetic solenoid is fixed to the case 44. Then, the locking and unlocking of the locking mechanism 43 is controlled by the CPU 6.

Next, the operation of the operating unit 10 will be described with reference to FIG. The upper part of FIG. 4 is a time chart of the operation of the electric motor, the middle part is a time chart of the operation of the clutch mechanism, and the lower part is a time chart of the lock mechanism. First, in the initial state, no voltage is applied to the electric motor 3, the clutch mechanism 42 is in the separated state, and the lock mechanism 43 is in the locked state.

Then, at time t0, when the collision detection unit 7 detects a collision or the collision prediction unit 8 predicts a collision, the CPU 6 applies a positive voltage to the electric motor 3 to apply a positive voltage to the motor shaft 30 of the electric motor 3. Is rotated forward in the direction of arrow A in FIG. The power of the electric motor 3 is transmitted from the motor shaft 30 to the fan shaft 20 via the gear mechanism 5 to rotate the rotary fan 2. The voltage applied to the electric motor 3 at this time is preferably, for example, the rated voltage of the electric motor 3.

At the same time, at time t0, the CPU 6 moves the locking pin to the electromagnetic solenoid of the locking mechanism 43 to release the locking mechanism 43. As a result, the mainspring 41 is released, and the spring shaft 40 rotates forward in the direction of arrow B in FIG. At this time, since the clutch mechanism 42 is in the connected state, the power of the mainspring 41 is transmitted from the spring shaft 40 to the fan shaft 20 via the clutch mechanism 42.

Here, the graph of FIG. 5 schematically shows the state of the time change of the rotation speed of the rotating fan 2. The horizontal axis of the graph in FIG. 5 represents time, and the vertical axis represents the rotation speed of the rotating fan 2. Then, in the graph of FIG. 5, the time change of the rotation speed of the rotary fan 2 in the case of the present embodiment is schematically shown by the curve I, and at the same time, the time of the rotation speed of the rotary fan 2 in the case of only the electric motor 3 is shown. The change is schematically shown by the broken line II.

In the present embodiment, as described above, immediately after the start of operation of the electric motor 3, in addition to the power from the electric motor 3, the power from the mainspring 41 is transmitted to the fan shaft 20. Therefore, as shown by the curve I, the rotation speed of the rotating fan 2 increases sharply as compared with the rotation speed of the electric motor 3 alone shown by the broken line II, and the rotation speed of the rotating fan 2 at the steady rotation speed of the electric motor 3 alone. Reach the number of revolutions exceeding. Therefore, air can be supplied to the airbag with a large air volume immediately after the operation of the electric motor 3 is started. As a result, the airbag can be expanded and deployed in a short time.

Subsequently, the CPU 6 sets the clutch mechanism 42 into the separated state from the time t0 to the time t1 after the lapse of the predetermined time Δt. As a result, the power from the mainspring 41 is not transmitted to the rotary fan 2. This is to prevent the mainspring 41 from hindering the rotation of the rotary fan 2 because the rotational force of the mainspring 41 decreases with time. Here, the predetermined time Δt depends on the mechanical characteristics of the electric motor, but as an example, in the case of an electric motor for a bumper airbag, it is, for example, 1 second.

After time t1, the rotary fan 2 rotates only by the power of the electric motor 3. Therefore, as shown in the curve I of FIG. 5, the rotation speed of the rotating fan 2 decreases from the peak rotation speed to reach the rotation speed in the steady state.

Subsequently, at time t2, the CPU 6 sets the voltage applied to the electric motor 3 to 0. As a result, the rotation of the rotary fan 2 is stopped. The duration of operation of the electric motor 3 is preferably adjusted according to, for example, the physique of the occupant.

Further, at time t3 after a predetermined time has elapsed after the passenger car has stopped, the CPU 6 applies a negative voltage to the electric motor 3 this time to rotate the motor shaft 30 of the electric motor 3 with the arrow C in FIG. Reverse rotation in the direction of. The power of the electric motor 3 is transmitted from the motor shaft 30 to the fan shaft 20 via the gear mechanism 5, and causes the rotating fan 2 to rotate in the reverse direction. As a result, the air in the expanded airbag 1 is exhausted.

At the same time, at time t3, the CPU 6 connects the clutch mechanism 42. As a result, the rotation of the fan shaft 20 is transmitted to the spring shaft 40, and the spring shaft 40 rotates in the reverse direction in the direction of arrow D in FIG. As a result, the mainspring 41 is wound around the spring shaft 40 again.

Subsequently, at time t4, the CPU 6 puts the clutch mechanism 42 into the separated state again, and at the same time, puts the lock mechanism 43 into the locked state again.

Further, at time t5 after the airbag 1 is sufficiently exhausted, the CPU 6 sets the voltage applied to the electric motor 3 to 0 and stops the rotation of the electric motor 3. After that, the CPU 6 reconnects the clutch mechanism 42. As a result, the electric motor, the clutch mechanism 42, and the lock mechanism 43 are in the same state as the initial state, and the airbag device is prepared to be used repeatedly.

Next, a second embodiment of the vehicle airbag device of the present invention will be described. First, the configuration of the vehicle airbag device of the second embodiment will be described with reference to FIG. As shown in FIG. 6, the vehicle airbag device of the second embodiment supplies air to the airbag 1 that expands and expands at the time of collision or collision prediction, and to expand and deploy the airbag 1. The rotating fan 2 and the DC electric motor 3 that rotates the rotating fan 2 and the electric motor 3 operate for a predetermined time from the start of operation to electrically increase the rotation speed of the rotating fan 2. It is composed of a power supply unit 9.

Next, the operation of the vehicle airbag device of the present embodiment will be described with reference to the time chart of FIG. First, in the initial state, no voltage is applied to the electric motor 3, and the electric motor 3 is stopped.

Then, at time t0, when the collision detection unit 7 detects a collision or the collision prediction unit 8 predicts a collision, the CPU 6 informs the power supply unit 9 of a short predetermined time of less than 1 second from the start of expansion and deployment of the airbag. An overvoltage exceeding the rated voltage of the electric motor 3 is applied to the electric motor 3 for a time Δt. Here, the predetermined time Δt depends on the electrical characteristics of the electric motor, but as an example, in the case of an electric motor for a bumper airbag, it is, for example, about 0.5 seconds. Further, here, for example, an overvoltage of 18V, which is 1.5 times the rated voltage of 12V, is applied. In this embodiment, an example in which an overvoltage is applied will be described, but the same applies to the case where an overcurrent is applied.

As described above, when the overvoltage is applied to the electric motor 3 for a short time, the rotation speed of the rotating fan 2 rapidly increases and the rated voltage is applied to the electric motor 3 as in the first embodiment described above. It reaches a rotation speed that exceeds the rotation speed at the time of steady rotation. Therefore, air can be supplied to the airbag with a large air volume immediately after the operation of the electric motor 3 is started. As a result, the airbag can be expanded and deployed in a short time.

Subsequently, at time t1 after a predetermined time Δt has elapsed from time t0, the voltage applied by the power supply unit 9 to the electric motor 3 is reduced to the rated voltage by the CPU 6. This is to prevent the power supply motor 3 from being damaged by the overcurrent.

After time t1, the rotary fan 2 rotates only by the power of the electric motor 3. Therefore, as shown in the curve I of FIG. 5, the rotation speed of the rotating fan 2 decreases from the peak rotation speed to reach the rotation speed in the steady state.

Subsequently, at time t2, the CPU 6 sets the voltage applied to the electric motor 3 to 0. As a result, the rotation of the rotary fan 2 is stopped. Further, at a time t3 after a predetermined time has elapsed after the passenger car has stopped, the CPU 6 applies a negative voltage to the electric motor 3 this time to rotate the rotating fan 2 in the reverse direction. As a result, the air in the expanded airbag 1 is exhausted.

Subsequently, at time t4 after the airbag 1 is sufficiently exhausted, the CPU 6 sets the voltage applied to the electric motor 3 to 0 and stops the rotation of the electric motor 3. This prepares the airbag device for repeated use.

In each of the above-described embodiments, an example in which the present invention is configured under specific conditions has been described, but the present invention can be modified and combined in various ways, and the present invention is not limited thereto. For example, in the above-described embodiment, all of the various airbag devices shown in FIG. 1 are based on the present invention. However, for example, when a plurality of airbag devices are mounted on a vehicle, any of the airbag devices is used. Is according to the present invention, and the remaining airbag device may be a conventional inflator type.

Further, one operating device may be connected to a plurality of airbags via piping, and air may be supplied to the plurality of airbags by one rotating fan. Further, the application of the vehicle airbag device of the present invention is not limited to the arrangement of the airbags shown in FIG. 1, and can be applied to, for example, an airbag arranged at an arbitrary position such as a side airbag. .. Further, in the above-described embodiment, an example in which an electric motor is used as the rotary drive means has been described, but in the present invention, the rotary drive means is not limited to the DC electric motor.

<figref num="1">It is the schematic which shows the arrangement example of the vehicle airbag device mounted on the passenger car.</figref><figref num="2">It is the schematic which shows the structure of the vehicle airbag apparatus of 1st Embodiment.</figref><figref num="3">It is a perspective view which shows the structure of the operating part of the vehicle airbag device of 1st Embodiment.</figref><figref num="4">It is a time chart for demonstrating the operation of the vehicle airbag apparatus of 1st Embodiment.</figref><figref num="5">It is a graph which shows typically the time change of the rotation speed of the rotary fan by the vehicle airbag device of 1st Embodiment.</figref><figref num="6">It is the schematic which shows the structure of the vehicle airbag apparatus of the 2nd Embodiment.</figref><figref num="7">It is a time chart for demonstrating the operation of the vehicle airbag apparatus of the 2nd Embodiment.</figref>

Code description

1, 1a, 1b, 1c Airbag 2 Rotating fan 3 Electric motor 4 Mechanical rotation increasing part 5 Gear mechanism 6 CPU 7 Collision detection part 8 Collision prediction part 9 Power supply part 10, 10a, 10b, 10c Acting part 20 Motor rotation Shaft 30 Fan shaft 40 Spring shaft 41 Zenmai spring 42 Clutch mechanism 43 Lock mechanism 100, 100a, 100b, 100c Airbag device 101 Steering 102 Instrument panel 103 Driver seat 104 Passenger seat 105 Body