Abstract:
The mechatronic vehicle safety seat described transforms the geometry of the bottom frame and backrest frame associated with a head restraint when a collision is imminent. On a signal from a pre-crash detection device, or a manual or verbal indication, an energized solenoid instantly releases the forces of torsion springs and triggers the seat bottom and backrest for concurrent movement in sufficient time to mitigate excessive accelerations, loads and moments of forces acting upon seated occupants in response to impact modes. The distorted geometry of the bottom frame and backrest with head restraint enhances the safety performance of the seat belt and reduces the aggressiveness of airbags.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to the field of vehicle seats, and more particularly to driver and front passenger seats configured for minimizing collision injuries to vehicle occupants. 
       BACKGROUND OF THE INVENTION 
       [0002]    A number of practices and apparatuses have been devised to provide a vehicle seat for absorbing different forces, shocks, and vibrations commonly encountered in vehicular collisions. Several related patents are briefly described below. 
         [0000]    U.S. Pat. No. Re. 35,572 issued on Jul. 29, 1997 to Lloyd et al. discloses a seat assembly for a motor vehicle that includes an air suspension system for isolating the occupant of the seat from shock, vibration and inertial forces directed along both vertical and horizontal axes. A base plate is mounted to the floor of the vehicle and supports first and second pairs of sleeve bearings on opposed sides of a box-like housing. The housing is attached to a pair of guide rods, which cooperate with the sleeve bearings to provide fore and aft movement of the housing. Springs operating in cooperation with a first horizontally disposed air bag serve to dampen out inertial forces to the vehicle seat. The seat itself is supported on a vertically oriented air spring and a plurality of hydraulic vibration dampeners that tend to cushion vertically directed forces acting upon the seat and its occupant.
 
U.S. Pat. No. 2,227,717 issued on Jan. 7, 1941 to Jones relates to structure for mounting a chair to the body of an airplane. The structure is designed to move the chair forward and upward in the event of collision, whereby the person occupying the chair will be tossed in a curved path and thus relieved substantially from shock caused by the collision forces.
 
U.S. Pat. No. 3,081,059 issued on Mar. 12, 1963 to Hastings et al. is drawn to a seat base having an inverted cone secured to the underside of the seat. The front legs of the seat are pivotally mounted to the floor of the vehicle. A single rear leg telescopes against the action of a spring.
 
U.S. Pat. No. 4,275,914 issued on Jun. 30, 1981 to Holweg et al., discloses an arresting device in a longitudinally adjustable guide rail assembly for motor vehicle seats. The device includes a shaft rotatably supported in a stationary bearing plate and driven by a stationary electromotor. The driving pinion of the electromotor is in mesh with an intermediate gear, which is supported for joint rotation on the shaft. A coupling disk is supported for joint rotation on the shaft and for axial displacement between the bearing plate and the face of an intermediate gear.
 
U.S. Pat. No. 5,292,179 issued on Mar. 8, 1994 to Forget, discloses a fixed plate supporting a vehicle seat that is secured to longitudinal adjusting slides. The fixed plate supports a rotary intermediate plate via a first ball bearing and a cover rigidly connected to the fixed plate and supported at the rotary intermediate plate via a second ball bearing.
 
U.S. Pat. No. 5,344,204 issued on Sep. 6, 1994 to Liu, discloses a safe driver seat unit that includes a seat supported on two rails by four ball bearings mounted in the seat legs, and an arrangement wherein an electromagnetic controller locks the seat in normal position. In a collision, sensors will turn on power to unlock the seat so that springs may move the seat backwardly.
 
U.S. Pat. No. 5,605,372 issued on Feb. 25, 1997 to Al-Abdullateef, discloses an automotive safety seat that reduces g-loads imparted to an occupant during a collision by absorbing some of the energy of impact. Kinetic energy is converted to potential energy with the elevation of the seat and its occupant and the compression of springs.
 
U.S. Pat. No. 5,743,591 issued on Apr. 28, 1998 to Tame, discloses a vehicle seat, which includes a seat cushion assembly and a hydraulic actuator. A first mounting assembly is constructed and arranged to mount the seat cushion assembly on a vehicle floor, and a second mounting assembly is provided which is constructed and arranged to mount a seat back assembly on the seat cushion assembly.
 
U.S. Pat. No. 6,851,747 issued on Feb. 8, 2005 to the present inventor teaches a collapsible vehicle safety seat supported on a pivotable linkage. On vehicle impact or a signal indicating imminent impact, the linkage releases to drop the vehicle seat and the occupant to an angled position, reducing movement due to high deceleration forces.
 
German Patent No. 2,112,443 published Sep. 23, 1971, discloses a vehicle passenger safety system which has seat belt anchorages and/or the seat rear anchorage points attached through energy absorbing components so that each passenger describes a predetermined path within the compartment with an increasing braking force until suitable padding brings the passenger to a safe stop.
 
German Patent No. 2,060,951 published Jun. 22, 1972, discloses a car seat that is mounted on a spring-loaded support to absorb impact forces. The support is braced by either mechanical springs or hydraulic shock absorbers, and converts impact forces into a smooth recoil to protect the occupants in the event of a collision.
 
Great Britain U.S. Pat. No. 2,087,226A published May 26, 1982, discloses a shock absorbing seat that is formed by two connected portions. The shorter rear portion is a flat metal sheet bent upwardly at the back and riveted to the rear cross-member of a tubular support frame. The front portion includes a metal sheet, which is “waisted” in plan view and curved upwardly from the rear in side elevation to a smoothly curved peak from which it is bent downwardly as a flat vertical panel. The panel is riveted along its lower edge to the front cross-member of the support frame.
 
         [0003]    None of the above noted inventions and patents discloses a mechatronic vehicle safety seat, taken either singly or in combination, as described and claimed below. 
       SUMMARY OF THE INVENTION 
       [0004]    The mechatronic vehicle safety seat, called hereafter a vehicle safety seat, comprises an active bottom frame and backrest associated with a head restraint configured for concurrent movement when a collision is imminent. The vehicle safety seat adopts the latest pre-crash sensing technology (e.g. a radar sensor in the millimeter wave length range) for transmitting a command signal via an electronic control unit to a rotary solenoid. The energized rotary solenoid instantly releases forces of a first pair of torsion springs triggering a pair of movable shafts for releasing forces of a second pair of torsion springs to transform a quasi-hexahedron cuboid configuration to a quasi-pentahedron cuboid seat bottom frame and its supporting legs. The front and rear supported legs have upper and lower ends. The upper ends of the front legs are pivotally mounted to a front section of the seat bottom frame. The lower ends of the front legs are affixed in a conventional manner to the upper member of the seat height adjustment mechanism. The upper ends of the rear legs are pivotally connected to the rear section of the seat bottom frame. The lower ends of the rear legs are mounted pivotally to a slider positioned to interact with the upper member of the seat height adjustment mechanism, acting as sliding rails. When the actuator is energized, a pair of second torsion springs are released to move the seat rear legs from a vertical to a horizontal position and the seat bottom frame from the normal substantially horizontal orientation to a deployed angular orientation. 
         [0005]    A rigid bar at the rear of the seat support frame controls a set of third torsion springs interacting with the backrest frame and upper unit seat back recliner. The vertically positioned linkages connect the legs of the third torsion springs with the legs of a hinge for predetermined distortion of the backrest frame and the head restraint from a first to a second position. The top of the backrest frame has an open member positioned on the left side of the head restraints for uniform interaction between the backrest frame and the seat belt before, during and after a collision. The rear sections of the seat bottom frame and the lower edge of the backrest frame have a perimeter hidden inside of the seat cushion during normal driving conditions and exposed when the vehicle safety seat bottom frame and backrest frame are transformed to the second position. 
         [0006]    The invention described below provides improved elements and arrangements thereof in an apparatus for the purposes described which are dependable, flexible in movement, and fully effective in accomplishing their intended purposes. 
       OBJECTS OF THE INVENTION 
       [0007]    It is a principal object of the invention to provide a vehicle safety seat that utilizes the latest pre-crash detection technology to take corrective action to reconfigure the bottom frame geometry in sufficient time to mitigate excessive accelerations, loads and moments of force acting upon seated occupants in response to the impact. 
         [0008]    It is another principal object of the invention to provide a vehicle safety seat having an active backrest frame associated with a head restraint to interact with a seat recliner for instantly translating from a first configuration during normal car driving conditions to a second configuration when a collision is imminent. 
         [0009]    These and other objects of the invention will become readily apparent upon further review of the following specification, drawings and claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    Similar reference characters denote corresponding features consistently throughout the attached drawings. 
           [0011]      FIG. 1  is a side elevation view of the seat bottom frame supported having front pivoting legs and rear sliding legs in its normal configuration, according to the preferred embodiment of the present invention. 
           [0012]      FIG. 2  is a side elevation view of the seat bottom of  FIG. 1  supported in angular orientation by front pivoting legs and rear sliding legs in the deployed configuration. 
           [0013]      FIG. 3  is a side partial sectional view of the backrest frame with various interacting components in the normal configuration according to the preferred embodiment of the present invention. 
           [0014]      FIG. 4  is a side partial sectional view of a backrest frame of  FIG. 3  with various interacting components in the deployed configuration. 
           [0015]      FIG. 5  is a top sectional view of the seat bottom of  FIG. 1  including a rotary solenoid and schematic diagram showing the general relationship of the various components in the normal configuration. 
           [0016]      FIG. 6  is a top sectional view of  FIG. 5  showing the general relationship of the various components in the deployed configuration. 
           [0017]      FIG. 7  shows two graphs comparing head acceleration of a dummy occupying a vehicle safety seat versus a dummy in a stock seat from frontal sled test. 
           [0018]      FIG. 8  shows two graphs comparing moments of force acting on the left upper tibia of a dummy occupying a vehicle safety seat versus a dummy in a stock seat from frontal sled test. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0019]      FIG. 1  illustrates the general relation of various components of the vehicle safety seat in rest position during normal driving conditions according to the present invention. A seat bottom frame  10  is supported by a pair of front legs  110  and a pair of rear legs  40  (only one front leg and one rear leg seen). Seat bottom frame  10  is formed with three sections: frontal  10   a , middle  10   b  and rear  10   c  to maximize safety, comfort and ergonomics during normal driving conditions as well as when seat bottom  10  is transformed to a geometric supportive configuration when a collision is imminent. The essential function of frontal section  10   a  of seat bottom frame  10  is to protect occupant&#39;s legs, being one of the most frequently injured body parts due to a vehicle collision. The basic function of middle section  10   b  of seat bottom frame  10  is immobilizing occupants pelvis to alleviate kinematics of critical regions of an occupant&#39;s body. Rear section  10   c  of seat bottom frame  10  has a rigid bar  11  positioned horizontally and oriented perpendicular to the vehicle centerline (not shown). Rigid bar  11  is solely responsible for retaining a third torsion spring  32  (see  FIG. 3 ). The upper end of front leg  110  is pivotally connected to seat bottom frame frontal section  10   a  by pivot  90 . The lower end of front leg  110  is affixed to the front member of the seat height adjustment mechanism  110   a  most likely by means of a rivet. The upper end of rear leg  40  is pivotally attached to seat bottom frame rear section  10   c  by pivot  121 . The lower end of rear leg  40  is pivotally attached to slider  41  by pivot  42 . Slider  41  is held during normal driving by movable shaft  44  to serve as a latch. Biasing means, e.g. a second torsion spring  120 , is mounted between a rear section of seat bottom frame  10  and the upper end of rear leg  40 . Alternate biasing means, such as a tension/extension spring, is considered to be within the scope of the invention. Second torsion spring  120  is mounted to seat bottom  10  under tension in a manner to cause rear leg  40 , when slider  41  is released, to pivot in the direction indicated by arrow A, as described below. The upper member  60  of the seat height adjustment mechanism performs additionally as a sliding rail that uses a brass sleeve as an antifriction bearing surface. Sliding rail  60  is horizontally connected to front member  110   a  and rear member  110   b  of the height adjustment mechanism. The lower member  61  of the seat height adjustment mechanism is connected to a seat longitudinal adjustment mechanism (not shown). 
         [0020]      FIG. 2  illustrates the general configuration of the vehicle safety seat of  FIG. 1  in its deployed position when a collision is imminent, according to the present invention. The energized solenoid, as described below in relation to  FIG. 6 , has triggered the first torsion springs  48  (see  FIG. 5 ) for retraction of a latch  44  from slider  41 . After slider  41  has been released, a second torsion spring  120  pushes slider  41  over sliding rails  60  in association with rear legs  40 . The configuration of seat bottom frame  10  is transformed from a substantially horizontal orientation to a second angled position in sufficient time prior to an impact to mitigate accelerations, loads and moments of forces to a seated occupant. 
         [0021]      FIG. 3  illustrates the general configuration of the vehicle safety seat backrest portion in rest position during normal driving conditions, according to the present invention. The backrest frame  20  has a head restraint (not shown) mounted thereto, and a seat recliner  30 , a third torsion spring  32  held in tension by rigid bar  11 . A hinge  31  supports a rigid linkage  25  that is controlled by second torsion spring  32 . Latch  44  restrains slider  41  against the force of second torsion spring  120 . Rigid bar  11  holds the leg of second torsion spring  32  in tension condition. The normal location of backrest frame  20  is controlled by rigid linkage  25 , shown in the normal driving position. Rigid linkage  25  connects pivot  32   b  of second torsion spring  32  with pivot end  31   b  of hinge  31 . Pivot ends  31   b  and  32   b  are each pivotally assembled to backrest frame  20 . Third torsion spring  32  and hinge  31  are attached to seat recliner  30  by at least two corresponding points, upper point  31   a  and lower point  32   a . A pair of external stoppers  33   b  are mounted to seat recliner  30  for cushioning deployment of backrest frame  20  to the position seen in  FIG. 4 . Rigid linkage  25  is contained within a housing to isolate the movable assembly from a cushion of the backrest. 
         [0022]      FIG. 4  illustrates the vehicle safety seat according to the present invention as shown in  FIG. 3  in deployed position when a collision is imminent. Backrest frame  20 , third torsion springs  32 , rigid bar  11  fixedly connected to seat bottom frame  10 , hinge  31  and linkage  25  are instantly deployed from first to second position by second torsion spring  120  when latch  44  (see  FIG. 3 ) is retracted. The seat bottom frame  10  with rigid bar  11  are deployed to the orientation of  FIG. 4 , instantly releasing third torsion spring  32 . The vertically positioned rigid linkage  25  is forced down, moving backrest frame  20  rearward, as driven through corresponding upper pivot  31   b  and lower pivot  32   b . Third torsion spring  32  interacts with rigid linkage  25  for synchronizing backrest frame  20  relative to the stable position of seat recliner  30 . Two external stoppers  33   a  and  33   b  limit and cushion backrest frame  20  during transition from the first to the second position. The new orientation of seat bottom frame  10  along with the deployed position of backrest frame  20  and the connected head restraint (not shown) creates an additional suspension system for occupants, maintaining their optimum posture to withstand collision impact forces. Seat recliner  30  remains in its initial position before, during and after geometric transformation of the seat. 
         [0023]      FIG. 5  illustrates the general relationship of various components of the vehicle safety seat during normal driving conditions. A controllable release device, for example rotary solenoid  100 , is assembled through mounting studs (not shown) to horizontally positioned plate  80 . Plate  80  is connected to both sides of rear members of the seat height adjustment mechanism. Bar  101  interacts with a pair of first torsion springs  48 , affixed to respective links  48   a  and  48   b , to control the position of latch  44  through raised pins  49  pressed into links  48   a  and  48   b . Both first torsion springs  48  are held in the initial position by bar  101 , maintaining latch  44  in the extended position, thus latch slider  41  in the first position during normal driving conditions. First torsion springs  48  are mounted in tension to apply clockwise (right hand) force for rotating links  48   a  and  48   b  in the direction indicated by arrows C when released by bar  101  being rotated in the direction indicated by arrows B. The rotary motions of links  48   a  and  48   b  are converted to linear motion of latch  44 . The latches  44  are enclosed in channels  45  that are affixed to plate  80 . Channel  45  has a metal bearing sleeve to minimize surface friction between the interacting components. Slider rails  60  each have an antifriction surface  46  at the respective rear end for reducing the deployment time of latch  44 . The leads  102  connect electronic control unit ECU  50 , having a power supply  71 , e.g. 12V DC. A pre-collision detection system PDS device  72  (most likely radar in the millimeter wave length range) is provided to initiate the actions of the mechatronic vehicle safety seat when a collision is imminent. The electrical circuit also contains a transducer such as microphone  74  or an ergonomically placed pushbutton  73  to generate a command signal to ECU  50  for instantly energizing rotary solenoid  100 . The electrical circuit further has a manual return switch  75  to activate rotary solenoid  100  through a counter clockwise rotation and return links  48   a  and  48   b  to their initial zero degree position after a collision as indicated by arrow D. 
         [0024]      FIG. 6  illustrates the general relationship of the various components of the vehicle safety seat of  FIG. 5  in deployed condition when an impact is imminent. When the electronic control unit ECU  50  receives a signal from pre-crash detection system PDS  72 , a command signal is transmitted for energizing rotary solenoid  100  as illustrated. The angle and direction of rotation of bar  101  are predeterminated to release the forces of first torsion springs  48 . The first torsion springs  48  have links  48   a  and  48   b  controlled by a pin  49  raised from latch  44 . Raised pin  49  is affixed to each latch  44  and engages each respective link  48   a  and  48   b . The first torsion springs  48  convert the rotary motion of links  48   a  and  48   b  into linear motion to pull out latch  44  from sliders  41  (see  FIG. 5 ) to immediately release the forces of second torsion springs  120  (see  FIGS. 1-4 ). A sleeve  46  is provided in sliding rails  60  to enable latch  44  to minimize friction forces between two interacting parts. When latch  44  releases slider  41 , the rear slidable legs  40  (see  FIG. 2 ) change their initial vertical orientation to a horizontal orientation. Rotary solenoid  100  is allowed to rotate counter clockwise (left hand) to return to the de-energized position after a collision and reposition latch  44  into sliders  41  with rear legs  40  returned to their initial vertical orientation. 
         [0025]    As contemplated in related patents of the present inventor, an air bag incorporated with a seat belt (not shown) is designed to deploy toward the vehicle dashboard instead of toward the occupant. 
         [0026]      FIG. 7  and  FIG. 8  illustrate comparative graphs from a frontal sled test with pitch, where the pulse corridor is 16-18 G-s and the overall velocity change is 35 mph, and two identical dummies, i.e. 50 th  percentile adult male ATD were calibrated by accelerometers and load cells. The dummy occupying the safety seat experienced a safer, i.e. smaller and slower, reaction to the impact than the dummy in the stock seat.  FIG. 7  charts show that maximum head acceleration of the dummy in the safety seat was 32 G-s at 160 ms and 0 G-s at 240 ms, compared to the maximum head acceleration of the dummy occupying the stock seat which was 60 G-s at 120 ms and remained at 32 G-s at 240 ms.  FIG. 8  demonstrates the maximum moment of forces applied to the left upper tibia of the dummy in the safety seat which was 1358 in-lbs at 208 ms, compared to the maximum moment of forces acting on the left lower tibia of the dummy occupying the stock seat which was 3536 in-lbs at 120 ms and increased to exceed full scale. The mechatronic seat utilizes gravitational-inertial forces and the seat belt acts vertically to constrain occupants in sufficient time into a new geometric seat configuration, offering a safer position in anticipation of a collision, regardless of vehicle design specifications, seating environments, occupant&#39;s stature and initial position at the time of impact. Data demonstrated that the dummy occupying the safety seat of the present invention was subjected to considerably less accelerations, loads and moments of forces to all regions of the body than the dummy in the stock seat, especially the head and legs identified as the two most commonly injured body parts. 
         [0027]    The forces of the second synchronized torsion springs instantly distort angles and faces of a quasi-hexahedron cuboid seat bottom frame and pairs of front and rear supporting legs to a quasi-pentahedron cuboid that offers occupants an additional protective suspension system. Altering the seat bottom frame from a first to a second position releases the third torsion springs for instantly translating the geometric configuration of the backrest frame and head restraint from the first to the second position. The vehicle safety seat utilizes most effectively the occupant&#39;s natural reflex based on the human muscular reflex system for maintaining the optimal body position to withstand collision impact forces. Test results demonstrated that the vehicle safety seat improves the safety performance of seat belts by reducing loads applied to the occupant&#39;s shoulder and torso. This active seat function also reduces the aggressiveness of air bags. Importantly, the vehicle safety seat enhances protection of occupants seated in lightweight, fuel-efficient vehicles by diminishing the effect of a collision with a heavier and stiffer vehicle. 
         [0028]    The present invention is in no way restricted to the specific disclosure of the specification and drawings, but also encompasses any variations and modifications within the scope of the appended claims.