Abstract:
A foldable rollator includes: a main support frame including two spaced-apart front support rods; a rear support frame including two spaced-apart rear support rods pivotally coupled to the front support rods, respectively; 
     a plurality of wheels respectively installed on the main support frame and the rear support rods for rolling on the ground; an intermediate support frame coupled to the main support frame and the rear support frame, including a front support sub-frame pivotally coupled between the front support rods and a rear support sub-frame pivotally coupled between the rear support rods, the front and rear support sub-frames being further pivotally coupled to an axle; a seat unit disposed atop the intermediate support frame; and a backrest unit pivotally coupled to the axle.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority of Taiwanese Application No.100216985, filed on Sep. 9, 2011. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates to a wheeled ambulatory support, more particularly to a foldable rollator. 
         [0004]    2. Description of the Related Art 
         [0005]    A rollator is a type of walking aid for the elderly or patients suffering from conditions that hinder walking and functions by reducing the burden carried by the user&#39;s lower limbs. Generally, the rollator includes a pair of front support frames, two hand grips attached to the pair of the front support frames, respectively, a pair of rear support frames angularly and pivotally coupled to the front support frames, respectively, two transverse links with one attached between the two front support frames and the other attached between the two rear support frames, and four wheels, each of which is attached to a ground-attaching end of each of the front support frames and the rear support frames. 
         [0006]    Frequently, a rollator also includes two folding mechanisms. Each folding mechanism is disposed underneath a corresponding pivotal connection and includes two pivotally connected shafts connected to the respective front support frame and the corresponding one of the rear support frames coupled thereto, respectively. When the rollator is unfolded, the two shafts of each folding mechanism forma line. When the rollator is folded, the shafts of each folding mechanism are pivoted toward one another, causing the front support frames and the rear support frames connected thereto to pivot together until the rollator is at the folded position. 
         [0007]    However, because the primary users of rollators are the elderly and patients suffering from conditions that hinder mobility, this type of folding mechanism is burdensome because it requires the user to bend at the waist to effectively use the folding mechanism. In addition, this type of mechanism could cause injuries if fingers are caught in the folding mechanism. 
       SUMMARY OF THE INVENTION 
       [0008]    Therefore, the object of the present invention is to provide a foldable rollator that allows the elderly and patients suffering from conditions that hinder mobility to easily fold the rollator. 
         [0009]    Accordingly, a foldable rollator of the present invention comprises a main support frame, a rear support frame, a plurality of wheels, an intermediate support frame, a seat unit, and a backrest unit. 
         [0010]    The main support frame includes two spaced-apart front support rods, each of the front support rods having a top end and a bottom end opposite to the top end and a hand grip attached to the top end and extending therefrom. 
         [0011]    The rear support frame includes two spaced-apart rear support rods pivotally coupled to the front support rods. Each of the rear support rods has a top end and a bottom end opposite to the top end. The plurality of wheels are respectively installed on the main support frame and the bottom ends of the rear support rods for rolling on the ground. 
         [0012]    An intermediate support frame is coupled to the main support frame and the rear support frame below the pivotal connection therebetween and includes a front support sub-frame pivotally coupled between the front support rods and a rear support sub-frame pivotally coupled between the rear support rods. The front support sub-frame and the rear support sub-frame are further pivotally coupled to a transverse axle. The seat unit is disposed atop the intermediate support frame. The backrest unit is pivotally coupled to the transverse axle. 
         [0013]    In a use state of the rollator, the front support frame and the rear support frame are level, and in a non-use state of the rollator, the transverse axle is pulled upwards, causing the front support frame and the rear support frame to pivot towards each other, thus bringing the front support rods and the rear support rods together to move to the folded position. 
         [0014]    The effect of this invention resides in use of the pivot connection between the intermediate support frame and the connected backrest unit to simplify the folding process to a single step involving pulling upwards on the backrest unit. Not only does this eliminate the need to bend at the waist, which can be an arduous task for the ill and elderly, and decrease the amount of effort required to fold the rollator, it also eliminates the risk of injuring one&#39;s fingers during the folding process. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment with reference to the accompanying drawings, of which: 
           [0016]      FIG. 1  is a perspective view of the preferred embodiment of a foldable rollator according to the present invention at an unfolded position; 
           [0017]      FIG. 2  is a partially exploded perspective view to illustrate the detailed structure of the preferred embodiment of  FIG. 1 ; 
           [0018]      FIG. 3  is a perspective view to illustrate the preferred embodiment of  FIG. 1  at a folded position; 
           [0019]      FIG. 4  is an exploded perspective view to illustrate a hanging ring unit of the preferred embodiment of  FIG. 1 ; and 
           [0020]      FIG. 5  is a perspective view to illustrate a cup holder unit of the preferred embodiment of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0021]    With reference to  FIGS. 1 and 2 , the preferred embodiment of the foldable rollator of the present invention includes a main support frame  1 , a rear support frame  2 , an intermediate support frame  3 , a seat unit  5 , a backrest unit  6 , two front wheels  71 , and two rear wheels  72 . 
         [0022]    The main support frame  1  of the foldable rollator of this embodiment is a U-shaped body and includes: two spaced-apart front support rods  11 , each front support rod  11  having a top end  111 , a bottom end  112  opposite to the top end  111 , and a hand grip  13  attached to the top end  111  and extending therefrom; a connector beam  12  connecting the bottom ends  112  of the front support rods  11 ; and a pair of cover bodies  14 , each of which encapsulates the connection between each front support rod  11  and the corresponding hand grip  13  attached thereto. The rear support frame  2  includes a pair of rear support rods  21 . Each of the rear support rods  21  includes a top end  211  and a bottom end  212  opposite to the top end  211 . The top ends  211  of the rear support rods  21  are pivotally coupled to the front support rods  11  near their middle, respectively. The front wheels  71  are spaced-apart attached to the connector beam  12  of the main support frame  1  and the rear wheels  72  are attached to the bottom ends  212  of the rear support rods  21 , respectively. 
         [0023]    The intermediate support frame  3  is mounted under the pivotal connections between the front support rods  11  and the rear support rods  21 . The intermediate support frame  3  includes a front support sub-frame  31  and a rear support sub-frame  32 . The front support sub-frame  31  includes a front transverse link  311  pivotally coupled between the two front support rods  11  below the pivotal connection between the main support frame  1  and the rear support frame  2 , and also a pair of spaced-apart front pivot spokes  312  extending from the front transverse link  311  to define free end portions, respectively . The rear support sub-frame  32  includes a rear transverse link  321  pivotally coupled between the two rear support rods  21  below the pivotal connection between the main support frame  1  and the rear support frame  2 , and also a pair of spaced-apart rear pivot spokes  322  extending from the rear transverse link  321  to have free end portions, respectively. The free end portions of each front pivot spoke  312  and the corresponding one of the rear pivot spokes  322  are pivotally coupled to a transverse axle  4 . 
         [0024]    The seat unit  5  is a rigid structure disposed atop the intermediate support frame  3  and includes a seat body  51  having two positioning notches  52  dented from a top surface of the seat body  51 . In this embodiment, the seat body  51  is fixed to the rear pivot spokes  322  of the rear support sub-frame  32  using screws so that only the rear portion of the seat body  51  is fixed. Alternatively, the seat body  51  may be fixed to the front pivot spokes  312  of the front support sub-frame  31  so that only the front portion of the seat body  51  is fixed. The seat body  51  of this embodiment also includes a hatch  510  such that the user could lift the hatch  510  to gain access to a basket (not shown) placed underneath the intermediate support frame  3 . The positioning notches  52  form 45° angles with the normal line of the top e surface of the seat body  51  and extend along the transverse axle  4  through the sides of the seat body  51 . 
         [0025]    The backrest unit  6  includes a deep-U-shaped backrest frame  61  and a shallow-U-shaped positioning brace  62 . The backrest frame  61  has two arms pivotally coupled to the transverse axle  4  and a free opening end defined by the two arms, sharing the transverse axle  4  with the front support sub-frame  31  and the rear support sub-frame  32 . The positioning brace  62  has two arms pivotally coupled to the backrest frame  61  and defining a free opening end. The free opening ends of the backrest frame  61  and the positioning brace  62  face each at the unfolded position. 
         [0026]    In an unfolded state of the preferred embodiment, the front support sub-frame  31  and the rear support sub-frame  32  of the intermediate support frame  3  are level and mutually limit their positions. There is no fixed mechanism for limiting their positions. The seat unit  5  is levelly situated atop the intermediate support frame  3  and the positioning brace  62  engages the positioning notch  52  such that the backrest frame  61  is slanted upwards towards the hand grips  13 . In addition, when the user of the rollator becomes fatigued, he/she may sit on the seat unit  5  and lean against the backrest frame  61  to recuperate. 
         [0027]    With reference to  FIGS. 1 and 3 , in the embodiment, the rollator may be folded merely by holding onto the backrest frame  61  and pulling upwards such that the positioning brace  62  disengages the positioning notch  52 . As the backrest frame  61  is pulled upwards, because the backrest frame  61  is pivotally connected to the transverse axle  4 , the transverse axle  4  will be pulled upwards by the backrest frame  61 . Similarly, because the front support sub-frame  31  and the rear support sub-frame  32  are pivotally connected to the transverse axle  4 , they too will follow the transverse axle  4  upwards and thus form an angle therebetween. As the transverse axle  4  moves upwards, the angle between the front support sub-frame  31  and the rear support sub-frame  32  will diminish, thereby bringing the front support rods  11  and the rear support rods  21  together. Additionally, because only the rear end of the seat  51  is secured to the intermediate support frame  3 , the unsecured front portion of the seat  51  will separate from the front support sub-frame  31  and the seat  51  will tilt to remain parallel with the rear support sub-frame  32 . At this time, releasing the backrest frame  61  allows the backrest frame  61  and the positioning brace  62  to hang downwards. Further pushing the front support rods  11  and the rear support rods  21  together results in the folded state. 
         [0028]    With reference to the folded rollator in  FIG. 3 , unfolding the rollator involves a mere reversal of the steps above. Lifting the backrest frame  61  allows the front wheels  71  and the rear wheels  72  to roll apart and leveling the seat unit  5  such that the positioning brace  62  engages the positioning notch  52  will bring the rollator into the unfolded state as shown in  FIG. 1 . 
         [0029]    Referring to  FIGS. 1 ,  4  and  5 , the rollator further comprises two umbrella support devices  8  respectively disposed at two opposite outer sides of the main support frame  11 . Each umbrella support device  8  includes two spaced-apart hanging ring units  81 . 
         [0030]    Each of the hanging ring units  81  has a connecting rod  82  connected to the corresponding one of the front support rods  11  of the main support frame  1 , a hanging ring  83  connected for 360 degree rotation to the connecting rod  82 , and a limiting body  84 . In this embodiment, the connecting rod  82  is a steel wire. The hanging ring  83  includes a ring body  831 , a tubular body  832  extending radially from an outer surface of the ring body  831 , and a passage hole  833  extending through the ring body  831  and the tubular body  832 . The connecting rod  82  has one end configured as a hook to hang fixedly to the respective front support rod  11  of the main support frame  1 , and the other end extending through the passage hole  833  and formed with an external thread  821 . The limiting body  84  in this embodiment is configured as a ball having an outer diameter larger than an inner diameter of the passage hole  833 , and has an internal thread  841  engaged to the external thread  821  of the connecting rod  41  to prevent the connecting rod  82  from escaping from the hanging ring  83 . In this embodiment, the ring body  831  and the tubular body  832  of the hanging ring  83  are slightly resilient, and the passage hole  833  has a hole diameter slightly smaller than an outer diameter of the connecting rod  82 . As such, the connecting rod  82  extends through the passage hole  833  in a tight-fitting manner. Even though the hanging ring  83  can be rotated 360 degrees about the connecting rod  82 , the connecting rod  82  cannot easily slide relative to the hanging ring  83 . 
         [0031]    When the user needs to place an umbrella or a stick, the two connecting rods  82  are disposed at the same angle relative to the front support rod  11 , respectively and the two hanging rings  83  are rotated to corresponding angle, the umbrella or the stick can then be extended into the two hanging rings  83 . In this embodiment, the ball-shaped limiting body  84  can prevent sharp portion of the connecting rods  82  from scratching the user&#39;s hand or the surface of the umbrella or the stick. When there is no need to place the umbrella or the stick on the rollator, the connecting rods  82  and the hanging rings  63  can be rotated such that the entire hanging ring units  81  abut against the main support frame  1 . 
         [0032]    If a smaller rod-shaped object, such as an umbrella, a stick, etc., is to be placed on the rollator, each hanging ring  83  can be rotated close to the connecting rod  82  so as to move the limiting body  84  from one end of the ring body  831  that is proximate to the tubular body  832  to the other end of the ring body  831  that is distal from the tubular body  832 , thereby dividing a space defined by the ring body  831  into two. At this time, a smaller umbrella or stick may be inserted into one of the spaces in the ring body  831  without falling off. 
         [0033]    Referring to  FIGS. 1 and 5 , furthermore, in order to facilitate the user to place stably a beverage bottle or can on the rollator during pushing, each cover body  14  includes at least one positioning stud  141  projecting from an outer surface thereof. The rollator further comprises a cup holder  9  that is hung movably to the positioning stud  141 . The cup holder  9  includes a cup holder body  91  defining a bottle accommodation space, and a hanging portion  92  formed on the cup holder body  91 . In this embodiment, the hanging portion  92  is configured as a through hole that extends through one side of the cup holder body  91  and that has a size conforming with that of the positioning stud  141 . As such, the cup holder  9  of a single specification can be placed on a left side or a right side of the main support frame  1  according to the user&#39;s requirement. 
         [0034]    To sum up, this invention uses the pivot connection between the intermediate support frame  3  and the connected backrest unit  6  to simplify the folding process to a single step involving pulling upwards on the backrest unit  6 . Not only does this eliminate the need to bend at the waist, which can be an arduous task for the ill and elderly, and decrease the amount of effort required to fold the rollator, it also eliminates the risk of injuring one&#39;s fingers during the folding process. 
         [0035]    While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.