Abstract:
External inflatable safety bags are provided in this system which is adaptable for a variety of conveyances. A sensing means determines the speed and distance between the conveyance and an obstacle or another conveyance for selectively providing a warning signal to the driver to avoid a collision or to deploy the safety bags automatically when collision is imminent. The safety bags provide impact absorption as well as aerodynamic breaking of the speed of the conveyance.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a method and system for protecting the passengers and the conveyance in a collision or crash, and more particularly it relates to an external air bags system which may be deployed automatically or manually for saving the lives of the passengers in an accident. 
     Safety air bags are provided in automobiles, which would deploy within the cabin of the automobile in an accident for preventing injury to the passengers. Commonly, the safety air bags are installed at the steering wheel and/or the dash board, and they would be activated automatically in the accident to provide an impact cushion for the passengers in the front seats in the automobile. There are serious problems associated with the use of such safety air bags. The most severe problem is the tremendous force upon their deployment that they exert on the body and particularly the head of the passengers. Such force per se may cause fatal injury to the passengers, especially for passengers having a small stature or for children. Furthermore, such frontal air bags provide no protection to the passengers in the event of a side collision. 
     Furthermore, the body front structure of modern automobiles is designed to collapse under the impact force in a head on accident so as to allow some distance of deceleration for reducing the impact to the passengers. However, such measure for softening the impact has only a meager effect in many cases where heavy metal objects like the engine of the automobile is pushed backwards towards the occupants, the result is often deadly. Even when there is no injury to the occupants, the cost for repairing the damage to the automobile is very high and it is ever increasing. Also, additional costs are incurred when police and the ambulance are required to attend to the accident, and when hospitalization is required for the injured. For the above reasons, the automobile insurance cost is extremely high. 
     It is impractical to provide individual safety bags for all the passengers in a multipassengers conveyance, such as a train or bus, since the cost of installing an air bag for every seat in such vehicle is prohibitive and impractical. 
     In the crash of a public aircraft, there is always a considerable amount of injury or fatality suffered by a large number of passengers. The injury and fatality are caused by the enormous force the aircraft striking the ground or water, which completely destroys its structure. Similarly, boats, hovercraft and submarines may also involved in a crash with for example other boats, submarines, or with the dock or obstacles under the water. 
     Attempts have been made to provide external air bags on aircrafts to lessen the impact force with the ground in an accident. U.S. Pat. No. 5,259,574 to L. Carrot and U.S. Pat. No. 5,992,794 to I. Rotman et al show the provision of such external inflatable air bags at the underside of a helicopter. Also, in U.S. Pat. No. 5,765,778 to A. Otsuka, a plurality of external inflatable air bags are provided at the underside of an airplane for the same purposes. However, the air bags therein do not provide any deceleration of the descending speed of the aircraft. They merely provide cushioning of the impact at the end of the fall of the aircraft when it strikes the ground. Moreover, there is no protection provided to the front end of the aircraft, which usually sustains the heaviest damage in a frontal crash. 
     Also, in U.S. Pat. Nos. 5,646,613 and 5,959,552 both to Cho, U.S. Pat. No. 3,822,076 to Mercier et al, U.S. Pat. No. 5,725,265 to Baber, and U.S. Pat. No. 3,708,194 to Amit, external inflatable air bags are provided for an automobile to cushion the impact force in an accident. However, none the air bags shown in these patents provides a deceleration means to reduce the speed of the vehicle or any means which can capture an approaching vehicle in a head on crash situation. Also, none of these patents shows a safe and effective method of detecting the speed of an approaching object. The laser, maser, or radar system for such detection shown in these patents could cause injury to the eyes of a person when such detecting light beam is reflected from a polished surface such as the bumper of a vehicle. 
     For boats, hovercrafts, submarines and other water crafts normally a reverse thrust is used by reversing the rotation of the propellers to brake their forward movement. However, the braking action is slow due to the inertia of the craft in the forward direction. In order to avoid collision in an accident, an effective means must be provided to terminate their forward movement promptly and instantly. 
     SUMMARY OF THE INVENTION 
     It is a prime object of the present invention to provide an external safety inflatable air bags system which upon its activation provides an aerodynamic braking to reduce greatly the forward speed of a conveyance and also to provide a cushion to absorb the impact force in the collision. 
     It is another object of the present invention to provide an effective detection means for determining the approaching speed of another conveyance or object in a potential collision so as to produce a warning signal or signals to the operator of the conveyance to invoke an evasive action or to actuate the safety external inflatable air bags system at a predetermined time to save the lives of the occupants as well as the prevent detrimental destruction of the conveyance. 
     It is another object of the present invention to provide a control system which automatically activates the safety external inflatable air bags system when the other conveyance or object is approaching in a very high speed beyond the allowable time to issue a warning signal to the operator. 
     It is another object of the present invention to provide a safety external inflatable air bags system which greatly minimizes the damage to a conveyance in a collision. 
     It is yet another object of the present invention to provide a safety external inflatable air bags system which provides a floatation means for a conveyance when it crashes in water. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects and advantages of the present invention will become apparent from the following description of the preferred embodiments thereof in connection with the accompanying drawings in which 
     FIG. 1 is a schematic side elevation view showing the provision of a safety inflatable external air bags at the front of an automobile according to the present invention. 
     FIG. 2 is a top elevation view showing the mounting of sensors on an automobile for detecting the speed of an approaching automobile for selectively providing a warning signal to the driver of the danger of a collision or to deploy the safety air bag automatically when collision with the other automobile. 
     FIG. 3 is a side elevation view showing the construction of the sensor. 
     FIG. 4 is a graph showing the intensity of light of the image of an object appearing at the transducer in sensor. 
     FIG. 5 is an exemplary electrical circuit coupled to the transducer for selective providing the warning signal to the driver of the automobile of an impending collision, or deploying the safety air bag automatically when collision is imminent. 
     FIG. 6 is a top elevation view of the provision of a plurality of sensors on a boat for detecting potential collision of the boat with other objects. 
     FIG. 7 is a top elevation view showing the location of the safety inflatable air bags on the boat. 
     FIG. 8 is a side elevation view of FIG.  7 . 
     FIG. 9 is a top elevation view showing the provision of safety inflatable air bag on a hovercraft. 
     FIG. 10 is a side elevation view showing the provision of safety inflatable air bag on a helicopter according to the present invention. 
     FIG. 11 is a perspective side elevation view showing the provision of external safety inflatable air bags on an air plane according to the present invention. 
     FIG. 12 is a front elevation view of FIG.  11 . 
     FIG. 13 is a top elevation view of FIG.  11 . 
     FIG. 14 is a side elevation view showing the provision of the external safety inflatable air bag for a motorcycle according to the present invention. 
     FIG. 15 is a top elevation view of FIG.  14 . 
     FIG. 16 is a perspective side elevation view showing the provision of external safety inflatable air bags for a snowmobile according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     With reference to the drawings, an automobile  10  is provided with an inflatable external air bag  11  which has a relatively large size after in has been inflated in an accident so as to provide a cushion means to absorb the impact force of the automobile  10  with an oncoming automobile  12 . The front of the air bag  11 , depending on the speed of its expansion, forms an effective resistive wall to the air in front to provide an additional aerodynamic breaking for the automobile  10  to slow down its forward motion. The size of the air bag  11  is almost equal to the size of the vehicle  10 , and it has a rear compartment  1 A and a front compartment  11 B. The large size of the air bag  11  also provides a greater aerodynamic drag on the automobile  10 . The top front portion  11 C of the front compartment  11 B projects forward and is intended to capture the oncoming automobile  12 , and its bottom portion  11 D also extends outwardly forward and is intended to slide under the front of the oncoming automobile  12  to lift the latter off the ground. A plurality of openings  13  having similar or various different sizes are formed in the rear compartment  11 A in order to maintain the pressure of the bag  11  at a selected level such that the bag  11  would not exert a rebounding force to both automobiles  10  and  12  in the collision. The openings  13  are positioned in such a way as to afford maximum aerodynamic breaking depending on the size and weight of the automobile  10 . The front surface of the front compartment  11 E is ruffled with a plurality of depressions  14  so as to provide a maximum drag to the automobile  10  upon the bag&#39;s inflation. The bag  11  may additionally be weighted such that it would stay close to the ground upon its inflation to ensure that it would not rise above the automobiles  10  and  12 . The bag  11  is made of a fire retardant material to eliminate its contribution to the fire hazard to the automobiles in collision and it would act as a blanket to extinguish the fire if a fire occurs. Furthermore, the bag  11  may be made of a transparent material so that the vision of the operators of the automobiles  10  and  12  would not be blocked by the inflated bag. 
     Sensors  15 ,  16 ,  17  and  18  are provided in the automobile  10  to determine the approaching speed of the oncoming automobile  12  for the actuation of the air bag  11  when a collision is imminent. The sensors  15  and  16  detect the speed of the oncoming automobile entering the border of the dangerous distance for actuating an alarm circuit to provide an early warning signal to the driver of the automobile  10 . An alarm sound signal together and/or flashing warning light will be actuated to indicate the danger. At this stage, the driver of automobile  10  has the time to decide whether to take suitable evasive action such as turning away from the collision course, or to deploy the inflatable air bag  11  immediately. Sensors  17  and  18  provides the final detection of the imminent collision for deploying the inflatable air bag  11  automatically immediately. 
     As best shown in FIG. 2 the sensors  15  and  17  are mounted on the left side on the dashboard of the automobile  10  while the sensors  16  and  18  are mounted on the right side thereof The early warning sensors  15  and  16  detect the light source emitted by the oncoming automobile in relatively longer sensing conical areas  19  and  20 , while the final warning sensors  17  and  18  detect the light source emitted by the oncoming automobile in the relatively shorter sensing conical areas  21  and  22 . 
     The sensors  15  through  18  are generally constructed as best shown in FIG.  3 . Each sensor has an elongated housing  23  with a concave reflective mirror  24  adjustably mounted at its rear end with a threaded mounting ring. The mounting ring is fixedly secured to the housing  23  by a set screw  25 . The position of the reflective mirror  24  may be adjusted by loosening the set screw  25  and turning the mounting ring to move the mirror  24  back or forth to a selected position and then tightening the set screw  25  to secure it in place. A transparent disc  26  is fixedly mounted in the housing  23  at the focus of the reflective mirror  24  at which a brightest image of an object reflected from the mirror  24  is located. The object is schematically indicated by a light source  27 . A light image transducer  28  is mounted at the center of the transparent disc  26 . The reflective mirror  24  has a focal point  29 , and the point  30  is the center of curvature of the mirror  24 . The focal point  29  is located at approximately halfway between the mirror  24  and its center of curvature  30 . The position of the reflective mirror  24  is preadjusted such that the light source  27  at a predetermined distance would have the brightest image at the center of the transparent disc  26  at which the light image transducer  28  is located. The predetermined distance is the farthest point of the dangerous distance at which the oncoming automobile is located away from the automobile  10 . An electrical signal generated by the light image transducer  28  is sent to the electronic warning circuit by lead wires  31  to provide the warning alarm signal or to deploy the air bag  11  automatically. A light filter  32  is provided at the front end of the sensor. The light filter  32  reduces any ambient light interference in order to obtain a clear light image of the headlight or taillight of the oncoming automobile in the sensor. Since all automobiles nowadays are provided with daylight running headlights and will also soon be provided with all time running taillights, the sensors of the present invention are effective for detecting the possibility of a collision with an approaching vehicle without the use of harmful laser lights as in the prior art devices. 
     The relationship between the component parts of the sensor and the distance to the oncoming automobile is expressed by the following formula: 
     
       
         1/d+1/q=2/r 
       
     
     in which d is the distance between the reflective mirror to the oncoming automobile; 
     q is the distance between the transparent disc and the reflective mirror; and 
     r is the distance between the reflective mirror and its center point of curvature. 
     The intensity of the light image of the headlight or taillight of the oncoming automobile versus its speed or time as detected by the sensors is best shown in the graph of FIG. 4 in which the curve FAST indicates the approaching speed of the other automobile being fast, and the curve SLOW indicates the approaching speed of the other automobile being slow. When the approaching automobile is beyond the farthest point of the dangerous distance the intensity of the image is low. The intensity peaks when the other automobile is at the predetermined farthest point, and the intensity again diminishes as the other automobile approaching closer. The voltage output of the light transducer  28  is amplified and the amplified signal is sampled at a very high rate. Each of the sample is addressed by the time in nanoseconds or microseconds and the sampled output voltage is converted to a digital value by an analog to digital converter. The digital value may be stored in a memory of a microcomputer. When the stored digital value of any sample is greater than a predetermined value representing the peak value generated by the image of the colliding object. This peak value is selected as well as the value which is lower by a fixed level of approximately 70% both before and after the peak value. The time difference between these two lower levels is a measure of the speed of the approaching automobile. 
     FIG. 5 shows an exemplary electrical circuit operative for determing the speed of the approaching automobile. The circuit is actuated when the ignition switch  33  of the automobile  10  is switched on so that the voltage from the battery  34  is applied to a regulator  35 . The output of the regulator  35  is divided by the resistors  36  and  37  together with an op-amp  38  to provide an output middle voltage for operating subsequent op-amps. The output voltage of the regulator  35  is connected to the common ground through a capacitor  39  while the output middle voltage of the op-amp  38  is also connected to the common ground through a capacitor  40 . A resistor  41  is connected in series to the light transducer  31  which may be in form of a photo diode which generates an output electrical signal relative to the light intensity of the light image of the oncoming automobile in the sensors  15  through  18 . When the photo diode  31  is illuminated by the light from the oncoming automobile as represented by the light  27  in FIG. 3, the output electrical signal of the photo diode  31  goes higher. Thus, when the rate of rise and fall of the light on the photo diode  31  is higher, it would indicate a faster approaching object. The output electrical signal thus generated is amplified by an second op amp  42  by connecting to the negative input terminal of the latter through a series connected capacitor  43  and resistor  44 . A feedback resistor  45  controls the gain of the output signal of the op amp  42 . The output middle voltage of the op amp  38  is connected to the positive input terminal of the second op amp  42  to operate the latter. The output of the second op amp  42  is then passed through a plurality of high pass filters, and since an alarm is required at specific high speed, any signal corresponding to the lower speed can be virtually eliminated. Each high pass filter consists of a capacitor  46  connected directly to receive the output voltage from the second op amp  42  and to direct the same to the junction between a capacitor  47  and a resistor  48 . The other end of the resistor  48  is connected to the output terminal of an op amp  49 . The other end of the capacitor  47  is connected to the positive input terminal of the op amp  49  and also to a resistor  50 . The other end of the resistor  50  is connected to the output middle voltage of the op amp  38 . The output of the op amp  49  is connected to its negative input terminal. The values of these components are chosen to provide a very sharp cut off of the frequency. A plurality of such high pass filter may be provided as shown by the dotted lines. These high pass filters have a nominal gain of unity thus further amplification may be required for their output. The amplification is provided by a plurality of amplifiers which may have a similar construction. The negative input terminal of the first stage amplifier  51  is connected to the output of the high pass filters through series connected capacitor  52  and resistor  53 . A potentiometer  54  provides the feedback resistance to the amplifier  51 . The positive input terminal of the amplifier  51  is connected to the output middle voltage of the op amp  38 . The subsequent similar amplifiers are shown in dotted lines. After the amplification, the amplified output voltage is further applied to the positive input terminal of a amplifier  55  via a resistor  56 . The amplifier  55  serves as a Schmidt trigger. The ratio of the positive feedback resistor  57  and the resistor  56  determines the hysteresis of the Schmidt trigger. The switching voltage of the Schmidt trigger can be set by the voltage on the negative input terminal of the amplifier  55  by adjusting a potentiometer  58  which derives its voltage from the output voltage of the regulator  35  via a resistor  59 . The output of the Schmidt trigger is applied to a CMOS OR circuit  60 . As soon as the high speed is detected, there is an output of high voltage signal at the output of the amplifier  55  which goes high resulting the output of the OR circuit  60  to go high. The output of the OR circuit  60  remains high until it is discharged by a capacitor  61  and resistor  62  to the ground. The discharging period is chosen to be longer enough to allow sufficient time for the operator of the automobile  10  to respond to the warning signal of the approaching automobile or object at a high speed so that the operator may either take evasive action to change its course to avoid the collision or to deploy the inflatable air bag  11  immediately. As long as the output voltage of the OR circuit  60  is high, it would activate a first oscillator comprising of two invertors  62  and  63  of a hex invertor CMOS and the resistor  64  and the timing capacitor  65 . When the output voltage from the OR circuit  60  is low, the diode conducts and inhibits the oscillator. A second oscillator consisting of two series connected CMOS hex invertors  66  and  67  is caused to oscillate by a diode  68  when the output voltage from the first oscillator is high. A resistor  69  and a capacitor  70  connected to the second oscillator are chosen to have a higher period so as to enable the generation of a beeping warning alarm signal by a buzzer  71 . The output of the second oscillator is applied to the buzzer  71  through two invertors  72  and  73  connected in parallel and serving as a buffer. The buzzer  71  may be provided by a piezoelectric crystal. In order to also provide an alarm warning light, a transistor  74  is connected to the output of the second oscillator. The transistor  74  turns on a high efficiency light emitting diode  75  via a resistor  76  to provide a flashing warning light signal. 
     The sensors of the present invention may also be provided on a water craft for detecting any danger of its collision with other objects or other water crafts. As shown in FIG. 6, five sensors  77 ,  78 ,  79 ,  80  and  81  are provided one at the bow and two at both the starboard and port sides of the water craft  82 . The bow sensor  77  would activate a front double compartment inflatable air bag  83  upon detecting the approach of a colliding object therewith. The side sensors  80  and  81  on the starboard side would activate the double compartment inflatable air bags  84  and  85  respectively on the starboard side of the water craft, while the side sensors  78  and  79  would activate the double compartment inflatable air bags  86  and  87  located on the port side of the water craft. The double compartment inflatable air bags  83  through  87  are similar to air bag  11  for the automobile  10  except with the portion having openings therein located at the front therein so as to eliminate bounce upon impact. The front surface of the inflatable air bags  83  through  87  are all ruffled to provide aerodynamic breaking, and they are located on a horizontal line between the center of gravity and the center of buoyancy of the water craft  82  such that they would not topple the water craft  82  upon their deployment. They will provide an instant braking as well as shift of the direction of motion of the water craft when selected ones of them are deployed to avoid collision or for the purpose of emergency navigation. 
     Similarly, double compartment safety inflatable air bags  88 ,  89 ,  90  and  91  may be deployed on the four sides of a hovercraft  92  for the same purposes as best shown in FIG.  9 . 
     As shown in FIG. 10, similar safety inflatable air bags  93 ,  94  and  95  may be provided at the underside of a helicopter  96 . The openings  97  formed in the outer air bag  95  provide the aerodynamic breaking as well as reducing the bounce when the helicopter crashes onto the ground. The large inner air bags  93  and  94  provide the required buoyancy to maintain the helicopter afloat when it falls into water. The air bags are deployed manually by the pilot, since for a helicopter there is a sufficient time to deploy the air bags before it falls to the ground or water. 
     A plurality of inflatable air bags  98 ,  99 ,  100 ,  101   102  and  103  may be provided on an air plane  104  for the same purposes. Similar to that for a helicopter, the air bags may be deployed manually by the pilot. The air bag  98  located at the front end of the air plane  104  substantially wraps over the entire front end to reduce its destruction when the air plane crashes head on against a mountain side. The air bags  99  through  102  located on the two sides of the air plane  104  act as parachutes to slow down the speed of descend as well as a dragging means to reduce the forward motion of the air plane. The double compartment air bag  103  at the underside of the air plane  104  also reduces the speed descend of the air plane. It provides the cushioning means to absorb the impact when the air plane crashes onto the ground, and it also provides the floating means to maintain the air plane afloat when it falls onto water until rescue arrives. The air bags are so positioned so that they exert very low stress to the structure of the air plane upon their deployment. 
     The safety air bag system of the present invention may be provided on a motorcycle  105  as best shown in FIGS. 14 and 15. A single large air bag  106  having a plurality of pressure release openings  107  may be provided. The air bag  106  also has a wrap around shape upon its deployment so that it extends entirely over the top, front and two sides of the motorcycle  105  to provide full protection of the rider  108  and any passenger thereon. Sensors similar to those for an automobile may be provided to deploy the air bag  106  automatically. 
     Similar safety air bag system may be provided on a snowmobile  109  as shown in FIG.  16 . The front air bag  110  may be a double compartment air bag or a single air bag with a plurality of air releasing openings as for the motorcycle. An additional, air bag may be provided at the underside of the snowmobile  109  to provide the floating means to maintain it afloat when the snowmobile  109  falls into water. 
     Although preferred embodiments of the present invention have been described here in detail, those skilled in the art will recognize that various substitutions and modifications which may be made to the specific structures and methods of fabrication without departing from the scope and spirit of the invention as recited in the appended claims.