Patent Publication Number: US-2003222449-A1

Title: Frame of an electric cart

Description:
BACKGROUND OF THE INVENTION  
       [0001] The present invention relates to an electric cart, and more particularly an electric cart, of which the frame is constructed such that the rear wheels will vibrate within reduced range when the cart is moving along an uneven ground.  
       [0002] Referring to FIGS. 4 and 5, a frame of a conventional electric cart includes a front part  10 , and a rear part  20 . The front part  10  has a base, a seat support rod  101 , two bent support rods  104 , and a head tube  105 ; the bent support rods  104  are fixed to the front of the base; the head tube  105  is fixedly connected to the bent rods  104  at a lower end, and connected to a handle bar of the cart at an upper end; front wheels  106  are fitted to two sides of the front end of the base; the scat support rod  101  sticks upright form an rear end of the base with bent supplement rods  1011  helping same secured in position that are connected to lateral sides of the rod  101  as well as edges of the base. A seat  105  is connected to the upper end of the support rod  101 . The front part  10  further has a pair of holed pivotal portions  103  at two lateral sides of the rear portion of the base. The rear part  20  has rear wheels  201  fitted to two lateral sides of a rear portion of a base  203  thereof, each of the wheels  201  is provided with a shock absorber  202 . The rear part  20  is fitted to the front part  10  with an upper front portion being fixed to the rod  101 , and with a front portion of the base  203  being pivoted to the pivotal portions  103 . Thus, referring to FIG. 6, the shock absorber  202  can help reduce discomfort of the rider when the cart is ridden along an uneven ground.  
       [0003] However, the cart is found to have disadvantages as followings:  
       [0004] 1. Because the pivotal portions  103  are formed at the rear end of the front part  10  exactly beside the seat support rod  101 , the distance H 1  from the pivotal portions  103  to the hubs of the corresponding wheels  211  is relatively short. Consequently, when one rides the cart on an uneven ground, the rear wheels  201  are prone to vibrate up and down for such a long distance that the rider would feel very uncomfortable.  
       [0005] 2. The head tube  105  is only held in position with two rods  104 , therefore the position thereof is prone to change when it hits objects, causing injure of the rider. And, the bent support rods  104  are in no position to protect the lower portions of the legs of the rider due to the position and shape thereof.  
       [0006] 3. The seat support rod  101  is provided with the supplement rods  1011  that can only prevent it from moving sideways, therefore it is not held in position ideally, i.e. at all of the sides.  
       SUMMARY OF THE INVENTION  
       [0007] Therefore, it is a main object of the present invention to provide an electric cart, which is constructed such that the rear wheels will vibrate within relatively small range when the cart is moving along an uneven ground.  
       [0008] It is another object of the present invention to provide an electric cart, which has a front section capable of protecting the lower portions of the rider&#39;s legs if the cart collides with other objects.  
       [0009] It is yet another object of the present invention to provide an electric cart, which is constructed such that a support rod for the seat is held in position with increased firmness. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0010] The present invention will be better understood by reference to the accompanying drawings, wherein:  
     [0011]FIG. 1 is an exploded perspective view of the frame of the electric cart according to the present invention.  
     [0012]FIG. 2 is a side view of the frame of the electric cart according to the present invention.  
     [0013]FIG. 3 is a side view of the frame of the electric cart of the present invention being moved along an uneven ground.  
     [0014]FIG. 4 is a perspective view of the frame of the conventional electric cart in the Background.  
     [0015]FIG. 5 is a side view of the frame of the conventional electric cart.  
     [0016]FIG. 6 is a side view of the frame of the conventional electric cart being moved along an uneven ground. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0017] Referring to FIGS. 1 and 2, a frame of an electric cart according to the present invention includes a front part  1 , and a rear part  2 .  
     [0018] The front part  1  has a base, a head tube  12 , a seat support rod  14 , and a securing combination, which includes an inverted U shaped member  19 , a T shaped member  18 , two tilted support rods  100 , and a tilted tube  17 . The base of the front part  1  has holed pivotal members  16  at intermediate portions of the lateral sides thereof. Front wheels  11  are fitted to front portions of lateral sides of the base. The seat support rod  14  is fixedly connected to the middle of the rear end of the base at a lower end.  
     [0019] The inverted U shaped member  19  is connected to the base at lower ends. The T shaped member  18  is connected to the base at a lower end, and are joined to a middle of the inverted member  19 , and a rear side of the seat rod  14  at two ends of an upper section thereof. The tilted rods  100  are connected to the inverted U shaped member  19 , and the base at two ends thereof. The tilted tube  17  is joined to a front side of the scat rod  14 , and the base at two ends thereof. Thus, the seat support rod  14  can be firmly held in position with the securing combination counteracting external force of all directions against the same.  
     [0020] Furthermore, a pair of bent supplement rods  13  are connected to the front portion of the base at two ends, and are connected to a respective one of the lateral sides of the head tube  12  at intermediate portions thereof such that the head tube  12  can be secured in position with increased firmness, and the front part  1  is strengthened. And, intermediate sections of the bent supplement rods  13  are formed with an increased height so as to be a protection against collision for lower portions of the rider&#39;s legs.  
     [0021] Rear wheels  21  are fitted to rear end portions of two lateral rods  22  of the rear part, and shock absorbers  24  are connected to the rear part  2  at lower ends thereof. The rear part  2  is connected to the front part  1  with the front ends of the lateral rods  22  being pivoted to the pivotal members  16 , and with upper ends of the shock absorbers  24  being connected to the securing combination. Sleeves  23  are fitted to the joints between the pivotal members  16  and the front ends of the lateral rods  22  of the rear part  2  such that the joints are strengthened, and noise of the lateral rods  22  pivoting on the pivotal members  16  can be reduced. In addition, the lateral rods  23 , and the pivotal members  16  are more hard-wearing due to the sleeves  23 .  
     [0022] Referring to FIG. 3, when the cart of the present invention, and the conventional cart in the Background are moved along an uneven ground, the rear part  2  will vibrate within a smaller range than that 20 of the conventional cart because the distance H 2  from the pivotal members  16  to the hubs of the corresponding wheels  21  is longer than that H 1  of the conventional cart. Therefore, the change of position of the pivotal members  16  in relation to the seat rod  14  helps reduce the range within which the rear part  2  will vibrate when the cart moves along an uneven surface.  
     [0023] From the above description, it can be seen that the cart frame of the present invention has advantages as followings:  
     [0024] 1. The rear part will vibrate within relatively small range when the cart is moving along an uneven ground, thus not causing discomfort of the rider.  
     [0025] 2. The front section of the frame is strengthened, and can protect the lower portions of the rider&#39;s legs if the cart collides with an object.  
     [0026] 3. The seat support rod is held in position with increased firmness.