Patent Publication Number: US-2018049556-A1

Title: Low Bed Structure for Car

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a bed and, more particularly, to a low bed structure for a car. 
     2. Description of the Related Art 
     A conventional low bed structure for a car in accordance with the prior art shown in  FIG. 1  comprises an actuator  50  having two ends connected with a fixed rack  10  and a movable rack  20  respectively. The actuator  50  includes a cylinder  52  and a push rod  54  retractably mounted on the cylinder  52 . The cylinder  52  of the actuator  50  is secured on the movable rack  20 . The push rod  54  of the actuator  50  is pivotally mounted on a protruding ear  100  of the fixed rack  10 . In operation, when the push rod  54  of the actuator  50  extends outward from the cylinder  52  of the actuator  50 , the actuator  50  pushes the movable rack  20  upward, with the protruding ear  100  functioning as a fulcrum, so that the movable rack  20  is driven by the actuator  50  to swing upward relative to the fixed rack  10 . On the contrary, when the push rod  54  of the actuator  50  retracts into the cylinder  52  of the actuator  50 , the actuator  50  pulls the movable rack  20  downward, so that the movable rack  20  is driven by the actuator  50  to swing downward relative to the fixed rack  10 . However, the actuator  50  is arranged on and will move with the movable rack  20 , so that the actuator  50  easily sways or vibrates due to its heavy weight, thereby affecting operation of the actuator  50  and movement of the movable rack  20 . In addition, the actuator  50  is easily worn out or inoperative due to frequent vibration during a long-term utilization, thereby decreasing the lifetime of the actuator  50 . 
     BRIEF SUMMARY OF THE INVENTION 
     In accordance with the present invention, there is provided a low bed structure for a car comprising an inner frame, a bed board and a lifting device. The inner frame supports the bed board. The bed board is mounted on the inner frame to cover the inner frame. The inner frame has a top bracket. The lifting device is mounted on the top bracket of the inner frame and includes a motor mounted on a center of the top bracket, a retractable rod connected with the motor, and a linking piece having a first end connected with the retractable rod and a second end connected with a substantially H-shaped support rack. In practice, the motor is operated to move the retractable rod which drives the H-shaped support rack to produce an angle variation of the H-shaped support rack so as to lift or lower the bed board. 
     According to the primary advantage of the present invention, the motor is mounted on the top bracket of the inner frame and will not swing with the bed board so that the motor is operated solidly and stably and will not be vibrated, thereby preventing the motor from being worn out due to frequent sway or vibration, so as to enhance the lifetime of the motor. 
     Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
         FIG. 1  is a perspective view of a conventional low bed structure for a car in accordance with the prior art. 
         FIG. 2  is a perspective view of a low bed structure for a car in accordance with the preferred embodiment of the present invention. 
         FIG. 3  is a perspective view of a bed board of the low bed structure for a car in accordance with the preferred embodiment of the present invention. 
         FIG. 4  is a perspective view showing the low bed structure being pivoted upward. 
         FIG. 5  is a side cross-sectional view of the low bed structure for a car as shown in  FIG. 4 . 
         FIG. 6  is a schematic operational view of the low bed structure for a car as shown in  FIG. 5 , showing the low bed structure being pivoted downward. 
         FIG. 7  is a schematic operational view of the low bed structure for a car as shown in  FIG. 6 , showing the low bed structure being pivoted downward. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings and initially to  FIGS. 2 and 3 , a low bed structure for a car in accordance with the preferred embodiment of the present invention comprises an inner frame  21 , a bed board  22  and a lifting device  23 . The inner frame  21  supports the bed board  22 . The bed board  22  is mounted on the inner frame  21  to cover the inner frame  21 . The inner frame  21  has a top bracket  211 . The lifting device  23  is mounted on the top bracket  211  of the inner frame  21  and includes a motor  231  mounted on a center of the top bracket  211 , a retractable rod  232  connected with the motor  231 , and a linking piece  233  having a first end connected with the retractable rod  232  and a second end connected with a substantially H-shaped support rack  234 . 
     In practice, the motor  231  is operated to move the retractable rod  232  which drives and changes an angle of the H-shaped support rack  234  to produce an angle variation of the H-shaped support rack  234  so as to lift or lower the bed board  22 . In such a manner, the motor  231  is mounted on the top bracket  211  of the inner frame  21  and will not move with the bed board  22  so that the motor  231  is operated solidly and stably and will not be vibrated so as to enhance the lifetime of the motor  231 . 
     In the preferred embodiment of the present invention, the lifting device  23  is arranged on a front portion  221  of the bed board  22  to lift or lower the front portion  221  of the bed board  22 . The front portion  221  of the bed board  22  can swing upward and downward. Thus, the motor  231  is mounted on the top bracket  211  of the inner frame  21  and will not move with the front portion  221  of the bed board  22 . 
     When in use, the low bed structure is placed in a car, and a mattress is placed on the low bed structure, so that the height of the low bed structure has to be reduced to prevent the low bed structure from taking up too much space of the car. In general, the bed board  22  is placed on the bottom of the interior of the car, and the lifting device  23  is used to lift or lower the front portion  221  of the bed board  22  so as to adjust the inclined angle of the front portion  221  of the bed board  22 . 
     In operation, referring to  FIGS. 4-6  with reference to  FIGS. 1-3 , the retractable rod  232  extends from the motor  231  of the lifting device  23  to function as the fulcrum of the pivoting action of the front portion  221  of the bed board  22 . When the retractable rod  232  is pushed forward by the motor  231 , the linking piece  233  is pivoted to drive and change the angle of the H-shaped support rack  234  so as to gradually lift the front portion  221  of the bed board  22  as shown in  FIG. 5 . On the contrary, when the retractable rod  232  is pulled backward by the motor  231 , the linking piece  233  is pivoted reversely to drive and change the angle of the H-shaped support rack  234  so as to gradually lower the front portion  221  of the bed board  22  as shown in  FIG. 6 . 
     As shown in  FIG. 7 , when the front portion  221  of the bed board  22  approaches a flat state, the retractable rod  232  still has a determined angle, so that the front portion  221  of the bed board  22  cannot be arranged in a flat manner completely. Thus, the front portion  221  of the bed board  22  is provided with a receiving hole  2211  to allow passage of the retractable rod  232 , so that the front portion  221  of the bed board  22  is disposed at a flat state completely without having to increase the thickness of the bed board  22 . 
     In another embodiment of the present invention, the lifting device  23  is arranged on a rear portion of the bed board  22  to lift or lower the rear portion of the bed board  22 . The rear portion of the bed board  22  can swing upward and downward. Thus, the motor  231  is mounted on the top bracket  211  of the inner frame  21  and will not move with the rear portion of the bed board  22 . In such a manner, the lifting device  23  is used to lift or lower the rear portion of the bed board  22  so as to adjust the inclined angle of the rear portion of the bed board  22 . 
     Accordingly, the motor  231  is mounted on the top bracket  211  of the inner frame  21  and will not swing with the bed board  22  so that the motor  231  is operated solidly and stably and will not be vibrated, thereby preventing the motor  231  from being worn out due to frequent sway or vibration, so as to enhance the lifetime of the motor  231 . In addition, the bed board  22  has a reduced thickness to save the inner space of the car. 
     Although the invention has been explained in relation to its preferred embodiment(s) as mentioned above, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the present invention. It is, therefore, contemplated that the appended claim or claims will cover such modifications and variations that fall within the true scope of the invention.