Patent Publication Number: US-2005133288-A1

Title: Motor vehicle with a shock-absorbing device for supporting a seat on a vehicle body

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      This invention relates to a motor vehicle that is suitable for a disabled driver, and more particularly to a motor vehicle that includes a shock-absorbing device for supporting a seat on a vehicle body.  
      2. Description of the Related Art  
      Although a conventional motor vehicle designed for a disabled driver is provided with some shock-absorbing devices between a vehicle frame and the wheels, a seat of the conventional motor vehicle can still be subjected to a relatively large shock, thereby resulting in discomfort of the disabled driver.  
     SUMMARY OF THE INVENTION  
      The object of this invention is to provide a motor vehicle that includes a shock-absorbing device for supporting a seat on a vehicle body.  
      According to this invention, a motor vehicle includes a wheeled vehicle body, a driving device for driving the vehicle body to move on the ground, a seat, and a shock-absorbing device for supporting the seat on the vehicle body. The shock-absorbing device includes a vertical mounting tube fixed on the vehicle body, and a damping unit disposed between the mounting tube and the seat such that the seat can move vertically on the mounting tube and such that the damping unit can retard vertical movement of the seat relative to the mounting tube. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      These and other features and advantages of this invention will become apparent in the following detailed description of a preferred embodiment of this invention, with reference to the accompanying drawings, in which:  
       FIG. 1  is a partly exploded perspective view of the preferred embodiment of a motor vehicle according to this invention;  
       FIG. 2  is an exploded perspective view of the preferred embodiment;  
       FIG. 3  is a longitudinal sectional view of the preferred embodiment;  
       FIG. 4  is a fragmentary sectional view of the preferred embodiment taken along Line IV-IV in  FIG. 3 ; and  
       FIG. 5  is a longitudinal sectional view of the preferred embodiment, illustrating how a seat is moved relative to a vehicle body when the vehicle body is subjected to a shock. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      Referring to  FIG. 1 , the preferred embodiment of a motor vehicle according to this invention is shown to include a wheeled vehicle body  1 , a driving device  2 , a seat  3 , and a shock-absorbing device  4 .  
      The vehicle body  1  includes a vehicle frame  11  and a plurality of wheels  12  mounted rotatably on the vehicle frame  11 .  
      The driving device  2  is mounted on the vehicle frame  11  in a known manner so as to drive the vehicle body  1  to move on the ground.  
      The seat  3  is supported on the vehicle frame  11  by the shock-absorbing device  4 .  
      Referring to  FIGS. 2, 3 , and  4 , the shock-absorbing device  4  includes a vertical mounting tube  5  made of metal and fixed on the vehicle frame  11 , and a damping unit  6  that is disposed between the mounting tube  5  and the seat  3  such that the seat  3  can move vertically on the mounting tube  5  and such that the damping unit  6  can retard vertical movement of the seat  3  relative to the mounting tube  5 . The damping unit  6  includes a lower bushing  61 , a vertical outer tube  62 , a spring  63 , an upper bushing  64 , a vertical inner tube  65 , a vertical central rod  66 , a locking member  67 , and a dust-protective sleeve  68 . The inner and outer tubes  65 ,  62  are made of metal.  
      The outer tube  62  is disposed within the mounting tube  5 , and includes a horizontal plate  621  and a tube body  622 . The horizontal plate  621  is disposed in and is formed integrally with the tube body  622 . Each of the mounting tube  5  and the outer tube  62  has a lower end  51 ,  623  that is formed with two holes (H 1 ). A horizontal positioning bolt  627  extends through the holes (H 1 ) in the mounting tube  5  and the outer tube  62 , and engages a nut  628  so as to fix the outer tube  62  within the mounting tube  5 .  
      The lower bushing  61  is made of a plastic material, and includes a tubular portion  611  and a flange  612  extending radially and outwardly from an upper end of the tubular portion  611 . The tubular portion  611  is disposed between an upper end of the mounting tube  5  and the outer tube  62  so as to provide a stable joint between the mounting tube  5  and the outer tube  62  and so as to eliminate noise resulting from contact between the mounting tube  5  and the outer tube  62 . The flange  612  abuts against an upper end surface of the mounting tube  5 .  
      The inner tube  65  is disposed vertically and movably within and projects upwardly from the outer tube  62 , and includes a horizontal plate  651  and a tube body  652  that has an upper end  653  connected fixedly to the seat  3 . The horizontal plates  651 ,  621  of the inner and outer tubes  65 ,  62  define cooperatively a spring-receiving chamber (c) (see  FIG. 3 ) therebetween.  
      The spring  63  is configured as a coiled compression spring, is disposed within the spring-receiving chamber (c), and has a lower end  631  pressing against the horizontal plate  621  of the outer tube  62 , and an upper end  632  pressing against the horizontal plate  651  of the inner tube  65 .  
      The upper bushing  64  is made of rubber, and includes a tubular portion  641  disposed between an upper end of the outer tube  65  and the inner tube  62 , a flange  642  extending radially and outwardly from an upper end of the tubular portion  641  and abutting against an upper end surface of the outer tube  62 , an octagonal outer surface  643  engaging an octagonal inner surface  626  of the outer tube  62 , and an octagonal inner surface  644  engaging an octagonal outer surface  655  of a lower end portion of the inner tube  65 . That is, the upper bushing  64  is formed with a central bore having a non-circular cross-section. The inner tube  65  is received fittingly within the upper bushing  64  so as to prevent rotation of the inner tube  65  relative to the upper bushing  64 .  
      Because the lower bushing  61  is disposed between the mounting tube  5  and the outer tube  62  and because the upper bushing  64  is disposed between the inner and outer tubes  65 ,  62 , the manufacturing precision requirement of the mounting tube  5  and the inner and outer tubes  65 ,  62  can be reduced.  
      The locking member  67  is used to lock the upper bushing  64  on an upper end portion of the outer tube  62 , is configured as a C-shaped clamp, and includes a C-shaped retaining ring  671  sleeved around the upper end portion of the outer tube  62  and having two terminal ends, each of which is formed with a hole (H 2 ), a bolt  672  extending through the holes (H 2 ) in the terminal ends of the C-shaped retaining ring  671 , and a nut  673  engaging the bolt  672 . The upper end portion of the outer tube  62  is formed with an open-ended slot  624  therethrough so as to permit the outer tube  62  to be sleeved around the upper bushing  64  in a tight fit manner.  
      The central rod  66  extends through the coiled compression spring  63 , and has an upper end  661  that extends through a central hole  654  in the horizontal plate  651  of the inner tube  65 , and an externally threaded lower end  664  engaging a threaded hole  625  in the horizontal plate  621  of the outer tube  62  so as to be fastened to the outer tube  62 . The upper end  661  of the central rod  66  is formed with a flange unit that is biased by the coiled compression spring  63  to abut against a top surface of the horizontal plate  651  of the inner tube  65 . The flange unit includes a flange  662  extending radially and outwardly from the central rod  66 , and a rubber washer  663  that is sleeved around the central rod  66  under the flange  662  and that is clamped between the flange  662  and the horizontal plate  651  of the inner tube  65  by virtue of the biasing action of the coiled compression spring  63 . As such, the inner tube  65  is biased by the coiled compression spring  63  to move upwardly relative to the outer tube  62  to a predetermined position as shown in  FIG. 3 .  
      The dust-protective sleeve  68  is sleeved around the outer tube  62 , and has a lower end abutting against the upper bushing  64 .  
      Referring to  FIG. 5 , when the vehicle body  1  is subjected to a shock, the central rod  66  moves upwardly relative to the inner tube  65  so that the spring  63  is compressed.  
      With this invention thus explained, it is apparent that numerous modifications and variations can be made without departing from the scope and spirit of this invention. It is therefore intended that this invention be limited only as indicated by the appended claims.