Patent Publication Number: US-2021163274-A1

Title: Lifting device

Description:
FIELD OF THE INVENTION 
     The present invention generally relates to a device for lifting and moving heavy objects such as vehicles, cargo and equipment placed on a platform while maintaining the platform and the objects in a level position. 
     BACKGROUND OF THE INVENTION 
     Forklifts are commonly used to pick up and transport pallets with cargo loads stacked onto them. The forklifts are typically equipped with two parallel arms configured to slide under the pallet and with a hydraulic or electrical lift configured to raise the arms and the pallet. One disadvantage of forklifts is the lack of versatility as they are not configured to pick up and haul vehicles that are disposed on platforms, such as snow blowers, cars or tractors. It would, thus be desirable to provide a lift that could be used for lifting and transporting cargo having a wide spectrum of shapes, weights and sizes. It is important that the cargo be kept in a level position or slightly tilted backward so as not to create a hazard of the cargo falling as it is being transported. It would also be desirable that the cargo carrying platforms be configured to tether onto and to untether from the pickup and transporting vehicle safely and expeditiously. 
     SUMMARY OF THE PRESENT INVENTION 
     In one aspect of the present invention, a lifting device comprises: a support structure; a first lower horizontal arm pivotally attached at a first end to the support structure; a second lower horizontal arm pivotally attached at a first end to the support structure, the second lower horizontal arm being disposed in substantially the same horizontal plane as the first lower horizontal arm; a first upper horizontal arm pivotally attached at a first end to the support structure, the first upper horizontal arm being disposed above the first lower horizontal arm; a second upper horizontal arm pivotally attached at a first end to the support structure, the second upper horizontal arm being disposed above the second lower horizontal arm and being disposed in substantially the same horizontal plane as the first upper horizontal arm; a first vertical arm having at least one portion disposed perpendicularly with the first lower horizontal arm and at least one portion disposed perpendicularly with the first upper horizontal arm, the first vertical arm being pivotally attached at a first end to about a midpoint of the first lower horizontal arm; a second vertical arm having at least one portion disposed perpendicularly with the second lower horizontal arm and at least one portion disposed in perpendicular with the second upper horizontal arm, the second vertical arm being pivotally attached at a first end to about a midpoint of the first lower horizontal arm; a shaft having a first end attached to a second end of the first vertical arm, the shaft having a second end attached to a second end of the second vertical arm; and a lifting mechanism engaged with the shaft, the lifting mechanism adapted for exerting an upward pulling force on the shaft. 
     These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of the lifting device according to a first embodiment of the present invention. 
         FIG. 2  is a front view of the lifting device according to a first embodiment of the present invention. 
         FIG. 3  is a side perspective view of the lifting device according to a first embodiment of the present invention. 
         FIG. 4  illustrates a side view of the lifting device according to a second embodiment of the present invention. 
         FIG. 5  illustrates a front view of the lifting device according to a second embodiment of the present invention. 
         FIG. 6  is a side perspective view of the lifting device according to a second embodiment of the present invention. 
         FIG. 7  is a side view of a coupling component for attaching a forklift or a platform to the lifting device. 
         FIG. 8  portrays a component of the lifting device. 
         FIGS. 9A to 9D  represent various views and configurations of a first embodiment of a load carrying assembly that attaches to the lifting device. 
         FIGS. 10A and 10B  show a second embodiment of a load carrying assembly that attaches to the lifting device. 
         FIG. 11  shows the first embodiment of the load carrying assembly in position for attaching to the lifting device. 
         FIG. 12  illustrates the second embodiment of the load carrying assembly in position for attaching to the lifting device. 
         FIG. 13  illustrates the load carrying assembly of the first embodiment combined with the lifting device in a first configuration. 
         FIG. 14  illustrates the load carrying assembly of the second embodiment combined with the lifting device in a first configuration. 
         FIG. 15  depicts the load carrying assembly of the first embodiment combined with the lifting device in a second configuration. 
         FIG. 16  depicts the load carrying assembly of the first embodiment combined with the lifting device in a third configuration. 
         FIG. 17  portrays the load carrying assembly of the second embodiment combined with the lifting device in a second configuration. 
         FIG. 18  portrays the load carrying assembly of the second embodiment combined with the lifting device in a third configuration. 
         FIG. 19  illustrates the embodiment of the load carrying assembly described in  FIG. 12  combined with the lifting device in a fourth configuration. 
         FIG. 20  illustrates the embodiment of the load carrying assembly described in  FIG. 12  combined with the lifting device in a fifth configuration. 
         FIG. 21  represents the embodiment of the load carrying assembly described in  FIG. 12  combined with the lifting device in a sixth configuration. 
         FIG. 22  shows the load carrying assembly described in  FIG. 12  being detached from the lifting device. 
         FIG. 23  is a side perspective view of the lifting device according to a third embodiment of the present invention. 
         FIG. 24  is a side perspective view of the lifting device according to a fourth embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention. 
     It is the object of the present invention to provide a lifting device adapted for attaching to a platform configured for lifting and carrying heavy loads including, but not limited to, cargo and vehicles, and for lifting and transporting the platform such that the platform is maintained in a level position to minimize the risk of load droppage off the platform. It is also the object of the present invention to provide a lifting device configured to tether onto and untether off various load carrying platforms quickly and efficiently. 
       FIGS. 1-24  illustrate the embodiments of the lifting device  10  of the present invention. The lifting device  10  contains two lower horizontal arms  17 A and  17 B disposed substantially in parallel and in the same horizontal plane to one another. The lifting device  10  also comprises two horizontal upper arms  19 A and  19 B disposed substantially in parallel to one another and in about the same horizontal plane. 
     Upper horizontal arms  19 A and  19 B are disposed in a horizontal plane that is above that of horizontal arms  17 A and  17 B and located in vertical planes that are between the vertical planes of horizontal arms  17 A and  17 B. 
     One end of each of horizontal arms  17 A,  17 B,  19 A and  19 B is attached to a part of the lifting device  10  support structure  14 . The attachment may be done by pins inserted into holes drilled into the arms and in the support structure and reinforced by bolts. 
     The lower arms  17 A and  17 B are pivotally attached to support members  36 A and  36 B by pins  18 A and  18 B respectively and the upper arms  19 A and  19 B are pivotally attached to the support structure  14  respectively by pins  41 A and  41 B (not shown). 
     Vertical arms  16 A and  16 B are attached to and configured for lifting the horizontal arms  17 A and  17 B. Each of the vertical arms  16 A and  16 B contains a top portion  16 AT and  16 BT respectively that are disposed substantially vertically, a middle portion  16 AM and  16 BM angled at about 45 degrees toward horizontal arms  17 A and  17 B and a bottom substantially vertical portion  16 AB and  16 BB as shown in  FIG. 2 . A shaft  26  connects the top portions of the vertical arms  16 AT and  16 BT while the bottom vertical portions  16 AB and  16 BB of vertical arms  16 A and  16 B are pivotally attached to about a middle of each lower horizontal arm  17 A and  17 B by pins  24 A and  24 B respectively that are reinforced by bolts. 
     A lifting mechanism is engaged with the shaft  26  such that exerting an upward pull on the shaft  26  results in an upward movement of the vertical arms  16 A and  16 B and upward pivoting of the lower horizontal arms  17 A and  17 B. The lifting mechanism may be powered in several ways. 
     A cable  13  wound onto shaft  26  is actuated by winch  12  that is disposed on base  45  of the supporting structure  14  of the lifting device  70  as shown in  FIG. 24 . 
     The winch  12  actuating the cable  13  is installed on a vehicle and the lifting device  10  is attached to the vehicle.  FIG. 3  illustrates an attachment embodiment of the lifting device  10  to the vehicle. Tube  15  on the lifting device  10  is configured for inserting into tube  11  located on the vehicle and attached by a bolted pin passed through holes  25 A and  25 B in tube  11  and holes  27 A and  27 B (not shown) in tube  15 . 
     A piston  46  operated hydraulically or electrically is installed on the support structure of the lifting device  60  as shown in  FIG. 23 . 
     The forward ends of the horizontal arms  17 A,  17 B,  19 A and  19 B are adapted for attaching to a load carrying assembly  20  such as a platform of fork lift. In one embodiment portrayed in  FIGS. 9A-9D , the load carrying assembly  20  comprises a vertical support  42 , a platform  31 , and upper extensions  23 A and  23 B and lower extensions  23 C and  23 D attached to the vertical support  42 . Each extension  23 A,  23 B,  23 C and  23 D of the load carrying assembly  20  contains a center hole. The platform  31  may contain a cargo or be utilized as a forklift for picking up a pallet  37  on forks  43  that carries a load  38 . 
     In another load carrying assembly embodiment  30 , a containment member  44  is attached to the vertical support  42 . Coupling member  28 , to which an upper extensions  35 A and  35 B (not shown) and lower extension  35 C and  35 D (also not shown) are attached, is wedged inside the containment member  44 . The placement of the extensions  35 A,  35 B,  35 C and  35 C is similar to that illustrated in  FIGS. 10A-10B . Each extension  35 A,  35 B,  35 C and  35 C contains a center hole. 
     The attachment of load carrying assembly  20  to the lifting device  10  is made by: (i) lining up the holes  21 A and  21 B of the lifting device  10  upper arms  19 A and  19 B with the holes of extensions  23 A and  23 B respectively, (ii) lining up the holes  22 A and  22 B of the lifting device  10  lower arms  17 A and  17 B with the holes of extensions  23 C and  23 D respectively, and (iii) inserting bolted pins  39  through all the lined up holes to lock the attachment of the load carrying assembly  20  to the lifting device  10 . The combined load carrying assembly  20  and lifting device  40  is shown in various configurations in  FIGS. 13, 15 and 16 . 
     The attachment of load carrying assembly  30  to the lifting device  10  is made by: (i) lining up the holes  21 A and  21 B of the lifting device  10  upper arms  19 A and  19 B with the holes of extensions  35 A and  35 B on the coupling member  28  respectively, (ii) lining up the holes  22 A and  22 B of the lifting device  10  lower arms  17 A and  17 B with the holes of extensions  35 C and  35 D respectively, and (iii) inserting bolted pins  39  through all the lined up holes to lock the attachment of the load carrying assembly  30  to the lifting device  10 . The combined load carrying assembly  30  and lifting device  50  is shown in various configurations in  FIGS. 14, 17 and 18 . 
     Engaging the lifting mechanism to exert an upward pull on shaft  26  while the load carrying assembly is attached to the lifting device creates an upward pull on vertical arms  16 A and  16 B and lower horizontal arms  17 A and  17 B that pivot upward since they are attached to vertical arms  16 A and  16 B. The upward pivoting of the lower horizontal arms  17 A and  17 B also causes the upward lifting of the load carrying assembly as it is attached to the lower horizontal arms  17 A and  17 B and causes the upward lifting of the upper horizontal arms  19 A and  19 B as they are attached to the load carrying assembly as shown in  FIGS. 15 and 17 . This allows the load carrying assembly to be transported to its destination where the lifting mechanism is engaged to lower the load carrying assembly and place it on the ground such as it is shown in  FIGS. 16 and 18 . 
     The attachment of the lifting device  10  to the load carrying assembly that is accomplished by inserting bolted pins through the upper arms  19 A and  19 B, the lower arms  17 A and  17 B and the extensions  23 A,  23 B,  23 C and  23 D or  35 A,  35 B,  35 C and  35 D must be firm yet allow some pivoting in lifting the arms and the load carrying assembly. This may result in premature wear and tear on the arms, however. To remedy this problem, horizontal lift arms  17 A,  17 B,  19 A and  19 B are configured to be extendable and retractable. Vertical lift arms  16 A and  16 B may also be configured to be extendable and retractable in order to enable adjusting the positions of the horizontal arms relative to the vertical arms for optimum stability of the lifting device. Also, in many cases where the cargo is excessively heavy or has irregular shape, it is desirable to tilt the load carrying assembly backward to enhance the stability of the cargo in transportation. Also, in order to safely discharge the cargo, it may be desirable to slightly tilt the load carrying assembly forward. As will be seen, the extendable and retractable feature of the arms helps to accomplish this as well as helps disconnect the load carrying assembly  30  from the lifting device  10 . Lift arm extension may be accomplished by electric actuation, hydraulic power or spring loading. An extension member  32  is adapted to move forward or rearward to bring about lengthening or shortening an arm. 
     Generally, in the course of using the lifting device, only the upper lift arms  19 A and  19 B or the lower lift arms  17 A and  17 B need to be extended or retracted, but not both.  FIG. 8  shows an embodiment of an extendable and retractable arm.  FIGS. 19, 20, 21 and 22  illustrate use configurations for the lifting device  10  utilizing a coupling member  28  and utilizing extendable and retractable upper horizontal arms  19 A and  19 B. In order to tilt the load carrying assembly  30  backward, upper horizontal arms  19 A and  19 B are retracted while in order to tilt the load carrying assembly  30  forward, the horizontal arms  19 A and  19 B are extended toward the load carrying assembly  30 . It is noted that tilting the load carrying assembly  30  backward may also be achieved by extending the lower lift arms  17 A and  17 B extended toward the load carrying assembly  30 , while tilting the load carrying assembly  30  forward may be achieved by retracting the lower lift arms  17 A and  17 B. The use of the retractable and extendable arms to tilt the load carrying assembly  30  improves the stability of the load carrying assembly  30  in transportation and in discharging the load. 
     The downward tilting of the load carrying assembly  30  enables detaching the load carrying assembly  20  while leaving coupling member  28  attached to arms  17  and  19  as shown in  FIGS. 21 and 22 . This enables the load carrying assembly  30  containing the coupling member  28  to couple with and uncouple from various load carrying assemblies with speed and efficiency. 
     Attachment of the load carrying assembly  20  that does not contain a coupling member to the lifting device  10  is generally suitable for a more permanent attachment to the lifting device  10 , while attaching the load carrying assembly  30  to the lifting device  10  using a coupling member is advantageous for frequent attachments to multiple platforms.  FIGS. 4-6  portray various views of the coupling member  28  attached to the lifting device  10 . It is also noted that the lifting device  10  may contain guard plates  29 A and  29 B (not shown) that cover the sides of the lifting device support structure  14 .