Patent Publication Number: US-2023147944-A1

Title: Pusher lift cart

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Pat. Application No. 63/277,904 filed with the United States Patent and Trademark Office on Nov. 10, 2021, the entire contents of which is herein incorporated by reference. 
    
    
     BACKGROUND 
     1. Field 
     Example embodiments relate to a pusher lift cart and methods of using the same. 
     2. Description of the Related Art 
     Pusher lift carts are well known in the art and are used to move a variety of items. Quite often the lift carts use a scissors jack type of apparatus to move a cart bed upwards and downwards. Other lift carts use actuators, for example, pneumatic, electric, or hydraulic cylinders to lift the cart bed upwards and downwards. 
     SUMMARY 
     The inventor notes movement of axles can be quite difficult using conventional lift carts. Thus, in order to improve over the prior art, the inventor invented a new type of pusher lift cart having, amongst other things, a profile allowing axles be supported near the ground on which the pusher lift cart rests. An example of the pusher lift cart includes one or more actuators allowing an axle to be raised and lowered. In one nonlimiting example embodiment, a pusher lift cart includes two actuators allowing ends of the axle to be moved upwards and downwards. The two actuators may be operated independently of one another allowing the axle to be tilted, if so desired. In another embodiment the actuators are moved in a synchronous manner so that ends of the axle may be raised and/or lowered at the same time and at the same rate. 
     Disclosed is a pusher lift cart comprising a pusher lift cart main frame having first a first end and a second end, a first top section at the first end, a second top section at the second end, a first interfacing member on the first top section, a second interfacing member on the second top section, and an axle support section between the first top section and the second top section. The pusher lift car further includes a first pusher lift cart sub frame at the first end of the pusher lift cart main frame, the first pusher lift cart subframe having a first complementary interfacing member telescopingly engaged with the first interfacing member, and a second pusher lift cart sub frame at the second end of the pusher lift cart main frame, the second pusher lift car subframe having a second complementary interfacing member telescopingly engaged with the second interfacing member. The pusher lift car further includes a first actuator connected to the first top section and the first pusher lift cart subframe and a second actuator connected to the second top section and the second pusher lift cart subframe, wherein the first end and the second end of the pusher lift cart main frame are moved upwards and downwards by the first and second actuators. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Example embodiments are described in detail below with reference to the attached drawing figures, wherein: 
         FIG.  1    is a perspective view of a pusher lift cart in accordance with an example embodiment; 
         FIG.  2    is a top view of the pusher lift cart in accordance with an example embodiment; 
         FIG.  3    is a front view of the pusher lift cart in accordance with an example embodiment; 
         FIG.  4    is a section view of the pusher lift cart in accordance with an example embodiment; 
         FIG.  5    is an end view of the pusher lift cart in accordance with an example embodiment; 
         FIG.  6    is an exploded view of the pusher lift cart in accordance with an example embodiment; 
         FIG.  7    is a perspective view of a pusher lift cart main frame in accordance with an example embodiment; 
         FIG.  8    is a top view of the pusher lift cart main frame in accordance with an example embodiment; 
         FIG.  9    is a front view of the pusher lift cart main frame in accordance with an example embodiment; 
         FIG.  10    is a section view of the pusher lift cart main frame in accordance with an example embodiment; 
         FIG.  11    is a bottom view of the pusher lift cart main frame in accordance with an example embodiment; 
         FIG.  12    is a bottom/closeup view of the pusher lift cart main frame in accordance with an example embodiment; 
         FIG.  13    is a perspective view of a pusher lift cart subframe in accordance with an example embodiment; 
         FIG.  14    is a top view of the pusher lift cart subframe in accordance with an example embodiment; 
         FIG.  15    is a front view of the pusher lift cart subframe in accordance with an example embodiment; 
         FIG.  16    is a bottom view of the pusher lift cart subframe in accordance with an example embodiment; 
         FIG.  17    is a side view of the pusher lift cart subframe in accordance with an example embodiment; 
         FIG.  18    is a perspective view of a pusher cradle insert in accordance with an example embodiment; 
         FIG.  19    is a perspective view of a lower backer plate in accordance with an example embodiment; 
         FIG.  20    is a perspective view of an actuator mounting ear in accordance with an example embodiment; 
         FIG.  21    is a perspective view of a subframe tow plate in accordance with an example embodiment; 
         FIG.  22    is a view of a pusher lift cart supporting an axle in accordance with an example embodiment; and 
         FIG.  23    is a view is a view of a pusher lift cart supporting an axle in accordance with an example embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments are not intended to limit the disclosure since the disclosure may be embodied in different forms. Rather, example embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. In the drawings, the sizes of components may be exaggerated for clarity. 
     In this application, when a first element is described as being “on” or “connected to” a second element, the first element may be directly on or directly connected to the second element or may be on or connected to an intervening element that may be present between the first element and the second element. When a first element is described as being “directly on” or “directly connected to” a second element, there are no intervening elements. In this application, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     In this application, spatially relative terms merely describe one element’s relationship to another. The spatially relative terms are intended to encompass different orientations of the structure. For example, if a first element of a structure is described as being “above” a second element, the term “above” is not meant to limit the disclosure since, if the structure is turned over, the first element would be “beneath” the second element. As such, use of the term “above” is intended to encompass the terms “above” and “below”. The structure may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. 
     Example embodiments are illustrated by way of ideal schematic views. However, example embodiments are not intended to be limited by the ideal schematic views since example embodiments may be modified in accordance with manufacturing technologies and/or tolerances. 
       FIG.  1    is a view of a pusher lift cart  1000  in accordance with an example embodiment. The pusher lift cart  1000  of this example embodiment includes a pusher lift cart main frame  100  supported by a pair of pusher cart subframes  200 . The pusher cart subframes  200  include actuators  300  configured to move ends of the pusher lift cart main frame  100 . In one nonlimiting example embodiment the actuators  300  may be powered by a power source  400 . For example, the actuators  300  may be, but are not required to be, electrically powered linear actuators and the power source  400  may be a battery, for example, a 12 VDC battery. In  FIG.  1   , the subframes  200  are supported by one or more castor wheels  600 , however, other types of supports are envisioned. For example, rather than castor wheels  600 , the subframes  200  may be supported by skids or tractors. In example embodiments, the pusher lift cart  1000  may include one or more cradle inserts  500  to support an axle. The cradle inserts  500  may be part of, or associated with, the pusher lift cart main frame  100 . 
       FIGS.  2 - 6    show various views of the pusher lift cart  1000 . For example,  FIG.  2    is a top view of the pusher lift cart  1000 ,  FIG.  3    is a front view of the pusher lift cart  1000 ,  FIG.  4    is a section view of the pusher lift cart  1000  taken through section line 4-4 of  FIG.  3   ,  FIG.  5    is an end view of the pusher lift cart  1000 , and  FIG.  6    is an exploded view of the pusher lift cart  1000 . Because these views are self-explanatory, a detailed description thereof is omitted for the sake of brevity. Hereinafter a description of the various components of the pusher lift cart  1000  are described. 
       FIG.  7    is a view of the pusher lift cart main frame  100 . In the nonlimiting example of  FIG.  7   , the pusher lift cart main frame  100  has a first end  110  and a second end  120  with an axle support section  130  between the first end  110  and the second end  120 . As shown in at least  FIG.  7   , the axle support section  130  may have one or more cradle side plates  136  and  138  which may be configured to receive a cradle inserts  500 . The cradle inserts  500 , as will be explained, may support an axle. 
     In example embodiment, the first end  110  of the pusher lift cart main frame  100  may have a transition section and a top section  140 . Similarly, the second end  120  of the pusher lift cart main frame  100  may also have a transition section and a top section  150 . The transition section at the first end  110  of the pusher lift cart main frame  100  is shown as being comprised of a first straight vertical member  147  and a second straight vertical member  148 , however, this example is merely for the purpose of illustration and not meant to limit the invention. For example, the transition section may be comprised of straight inclined members or curved members instead. Similarly, the transition section at the second end  120  of the pusher lift cart main frame  100  may also be comprised a first straight vertical member  157  and a second straight vertical member  158 , however, this example is also merely for the purpose of illustration and not meant to limit the invention. For example, this transition section may be comprised of straight inclined members or curved members instead. 
     Referring again to  FIG.  7   , the top section  140  may include interfacing members  112  which may be configured to interface with complementary interfacing members  212  of the pusher lift cart subframe  200 . For example, in one nonlimiting embodiment, the interfacing members  112  and the complementary interfacing members  212  may resemble tubes or cylinders which engage each other in a telescoping manner. For example, the interfacing members  112  may resemble hollow cylinders and the complementary interfacing members  212  may resemble cylindrical tubes or posts insertable into the interfacing members  112 . In the alternative, the interfacing members  112  may resemble cylinders and the complementary interfacing members  212  may resemble hollow cylindrical tubes into which the interfacing members  112  may insert. Of course, the interfacing members  112  and complementary interfacing members  212  are not required to be cylindrical, for example, in another embodiment they may resemble square or rectangular tubes that engage each other in a telescoping manner. 
     The above teachings may also be pertinent to second end  120  of the pusher lift car main frame  100 . For example, the top section  150  may include interfacing members  122  which may be configured to interface with complementary interfacing members  212  of another pusher lift cart subframe  200 . For example, in one nonlimiting embodiment, the interfacing members  122  and the complementary interfacing members  212  may resemble tubes or cylinders which engage each other in a telescoping manner. For example, the interfacing members  122  may resemble a hollow cylinder and the complementary interfacing members  212  may resemble cylindrical tubes insertable into the interfacing members  122 . In the alternative, the interfacing members  122  may resemble cylinders and the complementary interfacing members  212  may resemble hollow cylindrical tubes into which the interfacing members  122  may insert. Of course, the interfacing members  122  and complementary interfacing members  212  are not required to be cylindrical, for example, in another embodiment they may resemble square or rectangular tubes that engage each other in a telescoping manner. 
     In example embodiments the top sections  140  and  150  may take several forms. In the example shown in the figures, the top sections  140  and  150  are shown as comprised of tube steel. For example, the first top section  140  is comprise of three pieces of tube steel  142 ,  144  and  146  welded together to form a solid section. Similarly, top section  150  may also be formed from three pieces of tube steel  152 ,  154 , and  156  welded together to form a solid section. However, it is understood this aspect of example embodiments is for purposes of illustration only. For example, rather than forming the top sections  140  and  150  from three pieces of tube steel, a molding or bending process may be employed to produce a section highly similar to the illustrated top sections  140  and  150  comprised of welded together tube steel members. 
     In example embodiments, the pusher lift cart main frame  100  may also include backer plates  160  and  162 . The backer plates may resemble rectangular plates welded to the transition sections (for example, transition members  147 ,  148 ,  157  and  158 ). The backer plates  160  and  162  increase may increase the strength of the pusher lift cart main frame  100  as well as provide stiffness to add stability to the pusher cart main frame  100 . 
     In example embodiments, the axle support section  130  may be configured to support an axle. In the nonlimiting example embodiment of at least  FIG.  7   , the axle support section  130  may be comprised of a first structural member  132  and a second structural member  134  spaced apart from one another. In the figures the first and second structural members  132  and  134  are illustrated as being comprised of tube steel, however, other types of structural members, for example, W-shapes, H-shapes, or I-shapes are contemplated. In the nonlimiting example of  FIG.  7   , the first structural member  132  may include a pair of cradle side plates  136  and  138  to accommodate the cradle inserts  500 . Though only two cradle side plates  136  and  138  are shown, it is understood there may be more than two. Further, in another embodiment, each of the first and second structural members  132  and  134  include cradle side plates configured to receive a cradle insert  500 . 
     In example embodiments the pusher lift cart main frame  100  is shown as being largely constructed as being made from tube steel. For example, each of members  132 ,  147 ,  142 ,  144 ,  146 ,  148 ,  134 ,  157 ,  152 ,  154 ,  156 , and  158  may be 4×2×¼ tube steel members welded together to form a substantially unitary whole. However, the tube steel size may be different depending on required strength. In addition, rather than using tube steel, other shapes may be used. For example, rather than fabricating members  132 ,  147 ,  142 ,  144 ,  146 ,  148 ,  134 ,  157 ,  152 ,  154 ,  156 , and  158  from 4×2×¼ tube steel, W-shapes, H-shapes, I-shapes, or even C-shapes may be used. 
     In example embodiments the top section  140  may include a pair of ears  149  on an underside thereof. Similarly, top section  150  may also include a pair of ears  159  on an underside thereof. The ears  149  and  159  (see  FIG.  20    for a close-up view of an ear) may facilitate a connection for the actuators  300  to the pusher lift cart main frame  100 . 
     As one skilled in the art will appreciate, the profile of the pusher lift cart main frame  100  has the axle support section  130  at a lower elevation than top sections  140  and  150 . As will be explained shortly, this arrangement will help facilitate keeping the axle support section  130  relatively close to the ground making it relatively easy to place an axle on the cradle inserts  500  (see  FIG.  1   ). 
       FIGS.  13 - 17    illustrate an example of a pusher lift cart subframe  200 . The pusher lift cart subframe  200  may serve several functions. For example, it may provide a support for the power source  400  as well as a support for the actuator  300 . To this end, the pusher lift cart subframe  200  may include a power source side plate  240  which may support the power source  400 . In the nonlimiting example of  FIGS.  13 - 17    the power source side plate  240  may be supported by a pusher lift cart subframe base member  214 . The base member  214  may, in one embodiment, be made from a structural member, for example, tube steel, but may also be made from some other type of structural member, for example, an I, W, H, or C shaped member. So far as supporting the actuator  300 , the base member  214  may include a pair of ears  250  (a close up shown in  FIG.  20   ) which may facilitate a pin type connection for the actuator  300 . 
     As shown in  FIGS.  13 - 17   , the example pusher lift cart subframe  200  includes the previously described complementary interfacing members  212  which may interface with the interfacing members  112  and/or  122 . In the nonlimiting example of  FIGS.  13 - 17   , the complementary interfacing members  212  are supported on a base member  214 . 
     The sides of the base member  214  of the pusher lift cart subframe  200 , in one embodiment, include transition members  222  and  224  which connect the base member  214  to upper members  218  and  220 . The upper members  218  and  220  may be made from tube steel, as shown in the figures, or some other type of structural member, for example, an I, W, H, or C shaped member, and the upper members  218  and  220  may include connections  219  and  221  to connect castor wheels  600  to the pusher lift cart subframe  200 . For example, the connections  219  and  221  may be quick change bolt castor plates. 
     As shown in the figures, the base member  214  may be on a lower elevation that the upper members  218  and  220 . This may allow the pusher lift cart main frame  100  to be moved closer to the ground than if the complementary interfacing members  212  were mounted on a structure having the same elevation as the upper members  218  and  220 . 
     In example embodiments the pusher lift cart sub frame  200  may include a tow plate  230  which may interface with a forklift, tow motor, or other industrial device. For example, the tow plate  230  may include a hole  232  through which a pin may connect the tow plate  230  to the forklift, tow motor, or other industrial device. 
     Referring back to  FIG.  1    and  FIG.  6   , when assembled the actuators  300  have one end connected to the base members  214  of the pusher lift cart subassemblies  200  via the ears  250  and another end connected to the pusher lift cart main frame  100  via the ears  149  and  159 . In addition, the pusher lift cart main frame  100  and the pusher lift cart sub frames  200  are sliding connected to one another via the interfacing members  112 ,  122  and complementary interfacing members  212 . When the actuators  300  are extended the interfacing members  112  and  122  slide along the complementary interfacing members  212  and the pusher lift cart main frame  100  moves upwards. When the actuators  300  are retracted the interfacing members  112  and  122  slide along the complementary interfacing members  212  and the pusher lift cart main frame  100  moves downwards. Because the actuators  300  may be operated independently, one end of the pusher lift cart main frame  100  may be moved upwards while the other end of the pusher lift cart main frame  100  may be moved downwards. In another situation, one end of the pusher lift cart main frame  100  may be moved upwards while the other end of the pusher lift cart main frame  100  does not move at all. In yet another situation, one end of the pusher lift cart main frame  100  may be moved upwards at a different rate than the other end of the pusher lift cart main frame  100 . Of course, each of the actuators  300  may be controlled so that each end of the pusher lift cart main frame  100  raises and lowers at the same time. 
     Due to the profiles associated with the pusher lift cart main frame  100  and the pusher lift cart subframes  200  the axle support section can be moved very near, if not on, the ground. For example, the axle support section may be moved onto the ground, within about one inch of the ground, within about two inches above the ground, etc. Such an arrangement makes it relatively easy to move an axle on the cradles  500  of the pusher lift cart  1000 . 
       FIGS.  22  and  23    illustrate the pusher lift cart  1000  with an axle  700  supported thereon. In  FIG.  22   , the actuators  300  of the subframes  200  are somewhat retracted which allows the main frame  100  to be in a relatively low position. However, in example embodiments, when the actuators  300  extend, the main frame  100  is lifted upwards as shown in  FIG.  23    allowing the axle  700  to be properly installed in a machine. 
     The subject matter of example embodiments, as disclosed herein, is described with specificity to meet statutory requirements. However, the description itself is not intended to limit the scope of this patent. Rather, the inventors have contemplated that the claimed subject matter might also be embodied in other ways, to include different features or combinations of features similar to the ones described in this document, in conjunction with other technologies.