Abstract:
A roller mechanism for transporting loads over a surface, the roller mechanism including a body, at least one roller assembly that permits the body to move in at least one translational direction, the roller assembly being rotatably connected to the body, and a lifting mechanism attached to the body such that the body is selectively rotatable relative to the lifting mechanism, wherein the lifting mechanism can be operated to lift the roller assemblies out of contact with the surface.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of Invention 
   This invention relates generally to rollers for transporting heavy loads. More particularly, the invention relates to rollers for transporting heavy loads having roller chains, wheels or other mechanisms which permit translational movement. 
   2. Description of Related Art 
   Heavy loads are often moved using a ram roller or a plurality of ram rollers. These ram rollers typically include a housing with a flat top surface and at least one roller assembly. These roller assemblies can be, but are not limited to, chain rollers. The load is placed on the flat top surface of the ram roller. The load is then moved in the translational direction of the ram roller by applying a pulling or pushing force on the load or the ram roller. 
   However, these ram rollers can only move in one translational direction. In order to move the load in a second translational direction, i.e., a translational direction different from the ram roller&#39;s current translational direction, the ram roller, specifically the roller assembly(ies), must be repositioned and redirected in the desired second direction. However, unnecessary delays and complications may result from the repositioning of the ram roller, especially when it bears a load. 
   In fact, when a ram roller bears a heavy load, a plurality of steps must be taken to reposition the roller. First, a lifting mechanism (i.e., a jack) is placed under the load and operated to lift the load off of the ram roller. After the load has been lifted off of the ram roller, the load is then “blocked,” or independently supported, to prevent the load from dropping. After the load has been properly and safely blocked, the lifting mechanism is removed and the ram roller is manually rotated until it is directed in the desired direction. Thereafter, the lifting mechanism is again reinserted to hold the load, the blocks are removed, and the load is then lowered by the lifting mechanism back onto the ram roller. The ram roller and load can then be moved in the new translational direction. 
   Obviously, a significant amount of time and effort is required to perform the above steps. Further, these steps increase the risks of damage to the load and of injury to workers conducting these steps. 
   SUMMARY OF THE INVENTION 
   To address these problems, this invention provides a swivel ram roller in which the load lifting mechanism is integrated with the ram roller assembly. This reduces the amount of time and effort necessary in order to change the direction of a swivel ram roller. 
   The invention, according to one exemplary aspect, includes a roller mechanism for transporting loads over a surface, including a body, at least one roller assembly that permits the body to move in at least one translational direction, the roller assembly being rotatably connected to the body, and a lifting mechanism attached to the body such that the body is selectively rotatable relative to the lifting mechanism, wherein the lifting mechanism can be operated to lift the roller assemblies out of contact with the surface. 
   The invention, according to another exemplary aspect, includes a roller mechanism for transporting loads over a surface, including a body, at least one roller assembly that permits the body to move in at least one translational direction, the roller assembly being rotatably connected to the body, and a lifting mechanism attached to the body such that the body is selectively rotatable relative to the lifting mechanism and the lifting mechanism can be operated to lift the body and the at least one roller from the surface. 
   The invention, according to another exemplary aspect, includes a roller mechanism for transporting loads over a surface including a body, at least one roller assembly that permits the body to move in a translational direction, the at least one roller assembly being rotatably connected to the body, and a lifting mechanism, wherein the lifting mechanism has a retracted state in which the lifting mechanism does not contact the surface and an extended state in which the lifting mechanism contacts the surface and supports the body and the roller assembly above the surface, wherein the body and the roller assembly are rotatable relative to the lifting mechanism when the body and the roller assembly are not in contact with the surface. 
   The invention, according to another exemplary aspect, includes a method of operating a roller mechanism on a surface, the roller mechanism having a body, at least one roller assembly for moving the body in at least one translational direction over the surface, the roller assembly being rotatably connected to the body and a lifting mechanism, including lifting, with the lifting mechanism, a load that has been placed on the roller mechanism by a predetermined distance, lifting, with the lifting mechanism after the load has been lifted the predetermined distance, the load, the body and the at least one roller assembly until the at least one roller assembly is out of contact with the surface, and rotating the body relative to the lifting mechanism. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Various embodiments of this invention will be described in detail with reference to the following figures, wherein: 
       FIG. 1  is an overall, perspective view of the swivel ram roller assembly according to a first embodiment of the invention; 
       FIG. 2  is a perspective, partially cross sectional view of the swivel ram roller assembly of  FIG. 1 ; 
       FIG. 3  is a front view of the swivel ram roller assembly of  FIG. 1 , with the side plate  204  removed, showing the swivel ram roller assembly in the retracted position; 
       FIG. 4  is an enlarged view of the lifting mechanism of the swivel ram roller of  FIGS. 1-3  in the retracted position; 
       FIG. 5  is a front view of the swivel ram roller assembly of  FIG. 1 , with the side plate  204  removed, showing the swivel ram roller assembly in the extended position; 
       FIG. 6  is an enlarged view of the lifting mechanism of the swivel ram roller of  FIGS. 1-5  in the extended position; and 
       FIGS. 7-11  illustrate the repositioning of a plurality of swivel ram roller assemblies according to  FIGS. 1-6 . 
   

   DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
   Referring now in detail to the drawings, there is illustrated, in  FIGS. 1-6 , a swivel ram roller of one embodiment of the invention. 
   Specifically,  FIGS. 1-6  show a swivel ram roller  100  with a body  200  and a lifting mechanism  300 . As shown in  FIGS. 1-3 , the body  200  includes a top wall  202 , side walls  204 ,  206 ,  208  and  210 , roller assemblies  220 ,  224 , axle assemblies  222 ,  226  for the roller assemblies  220 ,  224  and tabs  230 ,  232 . The top wall  202  is located on top of and connects the side walls  204 ,  206 ,  208  and  210  (the respective ends of the side walls  204 ,  206 ,  208  and  210  may also be connected). The tabs  230 ,  232  are located on an outside surface of the side walls  206 ,  208  and include an opening. The tabs  230 ,  232  can be engaged by a hook, rope, chain, cable or other mechanism to move the swivel ram roller  100 . 
   The roller assemblies  220 ,  224  are located within the side walls  204 ,  206 ,  208  and  210  and below the top wall  202 . As shown, the roller assemblies  220 ,  224  are chain roller assemblies which are rotatable about the axle assemblies  222 ,  226 , respectively. The axle assemblies  222 ,  226  are attached to the side walls  204 ,  210 . Roller assemblies such as roller assemblies  220 ,  224  and axle assemblies such as axle assemblies  222 ,  226  are common and well known in the industry, and thus are not described in detail. The roller assemblies  220 ,  224  rotate in two directions, clockwise and counterclockwise, from the perspective of  FIG. 3 , such that the swivel ram roller  100  can move in opposite directions  120 ,  122 . In other embodiments, the roller assembly can be a wheel with a central axle attached to the side walls  204 ,  210 , or a plurality of wheels. In yet other embodiments, any other types of wheel or roller arrangement which enable translational movement of the swivel ram roller  100  can be utilized. 
   The body  200  also includes internal walls  212 ,  214  which are between the roller assemblies  220 ,  224  and the lifting mechanism  300 , and below the top wall  202 . The internal walls  212 ,  214  extend between and are connected on their ends to the side walls  204 ,  210 . Internal walls  212 ,  214  partially house the lifting mechanism  300  to prevent large debris from contacting the lifting mechanism  300 . As should be appreciated, any suitable wall, divider or shield can be used to prevent large debris from contacting or interfering with the lifting mechanism  300 . In yet other embodiments, such walls, dividers or shields can be omitted. 
   As shown in  FIGS. 3-6 , the lifting mechanism  300  includes, from bottom to top, a foot  302 , nuts  304 ,  306 , a lift ring  308 , a hydraulic cylinder  310 , a swivel disk  320  and a top plate  330 . The top of the foot  302  is attached to or integral with the bottom of the hydraulic cylinder  310 . As shown in  FIG. 3 , the foot  302  is positioned a predetermined distance away from the ground when the lifting mechanism  300  is in the retracted position so that the foot  302  does not interfere with the movement of the swivel ram roller  100 . 
   The nuts  304 ,  306  are attached to or integral with an outer surface of the hydraulic cylinder  310  above the foot  302 . The nuts  304 ,  306  attach the lift ring  308  to the hydraulic cylinder  310 . In other embodiments, only one nut is used. Also, in yet other embodiments, a clamp can be used. As should be appreciated, any combination of nuts, washers, clamps or other retaining devices can be used in order to attach the lift ring  308  to the hydraulic cylinder  310 . As should also be appreciated, the nuts  304 ,  306  or other retaining device, lift ring  308  and hydraulic cylinder  310  can be formed as one unit capable of supporting and lifting the body  200  and a load, as discussed below. 
   As shown in  FIGS. 3 and 4 , the top surface of lift ring  308  is a predetermined distance  340  below the bottom surface of the top wall  202  when the hydraulic cylinder  310  is in the retracted position. As also shown in  FIGS. 3 and 4 , the lift ring  308  surrounds the entire outer surface of the hydraulic cylinder  310 . However, as should be appreciated, the lift ring  308  can obviously partially surround the outer surface of the hydraulic cylinder  310 , or can be replaced by fingers, flanges or other structural members which can selectively engage the top wall  202 , as discussed below. 
   As shown in  FIG. 4 , the top part of the hydraulic cylinder  310  extends above the top wall  202 . A hydraulic connection  312 , located in the swivel disk  320 , is connected to the hydraulic cylinder  310  above the top wall  202 . Hydraulic fluid is received from a hydraulic source  400  ( FIGS. 7-11 ), through the hydraulic connection  312 , by the hydraulic cylinder  310  to increase the hydraulic pressure in the hydraulic cylinder  310 . Conversely, hydraulic fluid is returned to the hydraulic source  400 , through the hydraulic connection  312 , from the hydraulic cylinder  310  to reduce the hydraulic pressure in the hydraulic cylinder  310 . As should be appreciated, the hydraulic cylinder  310  can be any currently available or later developed hydraulic cylinder that can move between two positions, namely, an extended position and a retracted position. In this regard, the hydraulic cylinder  310  can be a single acting or a double acting cylinder. If the hydraulic cylinder  310  is a double acting cylinder, two hydraulic connections  312  are located in swivel disk  320 . Obviously, any currently available or later developed lifting device can also be used that can also move between an extended position and a retracted position. 
   The swivel disk  320  is attached to or integral with the top part of the hydraulic cylinder  310 . The swivel disk  320  covers the top of the hydraulic cylinder  310 . As shown in  FIGS. 3 and 4 , the swivel disk  320  includes a side wall  322  that extends to the top of the top wall  202  when the hydraulic cylinder  310  is in the retracted position. In other words, as shown in  FIG. 4 , the swivel disk  320  covers the top of the hydraulic cylinder  310  and is in contact with the top wall  202  when the hydraulic cylinder  310  is in the retracted position. 
   When the hydraulic cylinder  310  is in the retracted position, the foot  302  is a predetermined distance above the ground. Specifically, as discussed, the swivel disk  320  is attached to or integral with the top of hydraulic cylinder  310  and the foot  302  is attached to, or integral with the bottom of hydraulic cylinder  310 . Thus, when the hydraulic cylinder  310  is in the retracted position, the swivel disk  320  is supported by the top wall  202 , and the foot  302  is maintained a predetermined distance above the ground by the hydraulic cylinder  310 . 
   The swivel disk  320  also includes a plurality of projections  324  that extend downwardly from the bottom surface of the swivel disk  320 . The plurality of projections  324  match and are received by a plurality of detents  220  that are formed in the top surface of the top wall  202 . The plurality of projections  324  are received in the plurality of detents  220  in order to prevent the lifting mechanism  300  from rotating independently relative to the body  200  when the lifting mechanism  300  is in the retracted position. In other embodiments, the plurality of projections extends upwardly from the top of the top wall  202  and are received by a plurality of detents in the bottom surface of the swivel disk  320 . Also, in yet other embodiments, a clamp can be used. As should be appreciated, any combination of nuts, washers, clamps or other retaining devices can be used in order to maintain the position of the lifting mechanism  300  relative to the body  200  when the lifting mechanism  300  is in the retracted position. 
   The top plate  330  is attached to or integral with the top of the swivel disk  320 . The top plate  330  is placed on top of the swivel disk  320  to receive a load. As should be appreciated, any load receiving structure can be placed on top of or otherwise attached to the swivel disk  320 . In other embodiments, the load receiving structure is omitted and loads are thus placed directly on the swivel disk  320 . 
   As shown in  FIGS. 3 and 4 , when a load is placed on the top plate  330  with the swivel ram roller in the retracted state, the force due to the load is transmitted from the top plate  330  to the swivel disk  320 , to the body  200 , and to the roller assemblies  220 ,  224 , Also, the swivel disk  320  remains in a fixed rotational position with respect to the body  200  because the projections  324  of the swivel disk  320  engage the detents  220  in the top plate  202 . 
   A description will now be provided of the transformation of the swivel ram roller  100  from a retracted state, as shown in  FIGS. 3 and 4 , to an extended state, as shown in  FIGS. 5 and 6 . Hydraulic fluid is passed to the hydraulic cylinder  310  from the hydraulic source  400 , via the hydraulic connection  312 , to increase the hydraulic pressure in the hydraulic cylinder  310 . When the hydraulic pressure is sufficiently increased, the hydraulic cylinder  310  initially extends downward until the foot  302  contacts the ground. When the foot  302  contacts the ground, the force due to the load switches to be borned by the hydraulic cylinder  310  and foot  302  instead of the body  200  and the roller assemblies  220 ,  224 . 
   After the foot  302  contacts the ground, a further increase in the hydraulic pressure causes the hydraulic cylinder  310  to extend upward. When the hydraulic cylinder  310  first extends upward, only the swivel disk  320  and the top plate  330  are moved upward with the hydraulic cylinder  310 . In other words, the body  200  is not moved upward when the hydraulic cylinder  310  first extends upward. As should be appreciated, when the swivel disk  320  and the top plate  330  initially move upward, the force due to the load is entirely transferred from the swivel disk  320  to the hydraulic cylinder  310  and the foot  302 . In other words, the force due to the load is no longer borne by the body  200  and the roller assemblies  220 ,  224 . 
   The swivel disk  320  and the top plate  330  first move upward with the hydraulic cylinder  310  by the predetermined distance  340 . As discussed, during this movement, only the swivel disk  320  and the top plate  330  move upwardly with the hydraulic cylinder  310 . As also discussed above, the predetermined distance  340  is the distance between the top of the lift ring  308  and the bottom of the top wall  202  when the swivel ram roller  100  is in the retracted position. As shown in  FIGS. 5 and 6 , this movement of the swivel disk  320  and the top plate  330  relative to the body  200  creates a gap  342  between the top of the top wall  202  and the bottom of the swivel disk  320 . In other words, when the hydraulic cylinder  310  moves upward and the distance between the top of the lift ring  308  and the bottom of the top wall  202  becomes shorter, the distance between the top of the top wall  202  and the bottom of the swivel disk  320  becomes larger. As should be appreciated, when the bottom of the swivel disk  320  is spaced from the top of top wall  202  by the gap  342 , the projections  324  at the bottom of the swivel disk  320  are disengaged from the detents  220  located on the top surface of the top wall  202 . The body  200  can rotate relative to the swivel disk  320  when the projections  324  are disengaged from the detents  220 . 
   After the top of the lift ring  308  comes into contact with the bottom of the top wall  202  and the hydraulic pressure in the hydraulic cylinder  310  continues to increase, the hydraulic cylinder  310  further extends upward. During this movement, the lift ring  308  (which is attached to the hydraulic cylinder  310 ) moves the body  200  upward. As shown in  FIGS. 5 and 6 , the body  200 , including the roller assemblies  220 ,  224 , are thus lifted off of the ground. 
   When the body  200  is lifted off the ground, the body  200  of the swivel ram roller  100  can be rotated around the lifting mechanism  300 . The lifting mechanism  300  remains stationary as the body  200  rotates around it. When an operator rotates the body  200  about the axis  124 , the operator only has to overcome frictional forces that are created by the load of the body  200  on the lift ring  308 . The operator does not have to overcome the force of the load placed on the top plate  330 . 
   In various embodiments, the body  200  is manually rotated about an axis  124  of the lifting mechanism  300  (see  FIG. 5 ). However, as should be appreciated, the body  200  can be rotated relative to the lifting mechanism  300  by any device currently available or later developed which can perform this function. 
   As discussed, the projections  322  of the swivel disk  320  match and are received by the detents  220  of the top wall  202 . As such, the body  200  can be rotated to any one of a plurality of positions as long the projections  322  align with the detents  220  when the lifting mechanism  300  is in the retracted position. 
   A description will now be provided of the transformation of the swivel ram roller  100  from the extended state, as shown in  FIGS. 5 and 6 , to the retracted state, as shown in  FIGS. 3 and 4 . When the hydraulic fluid is initially returned to the hydraulic source  400 , thus reducing the hydraulic pressure in the hydraulic cylinder  310 , the hydraulic cylinder  310 , the body  200 , the swivel disk  320  and the top plate  330  move downward until the roller assemblies  220 ,  224  contact the ground. Continued reduction in the hydraulic pressure in the hydraulic cylinder  310  causes the hydraulic cylinder  310 , the swivel disk  320  and the top plate  330  to move downward by the height of gap  342  such that the projections  324  are received and engaged by the detents  220 . When the projections  324  are engaged by the detents  220 , the lifting mechanism  300  and the body  200  are placed in a fixed rotational position. Also, when the lifting mechanism  300  moves downward by the height of the gap  342 , the predetermined distance  340  is created between the top of the lift ring  308  and the bottom of top wall  202 . 
   When the hydraulic pressure in the hydraulic cylinder  310  is further reduced, the foot  302  is lifted from the ground. As should be appreciated, the force applied by the load on the top plate  330  is transferred from the hydraulic cylinder  310  and the foot  302  to the body  200  and the roller assemblies  220 ,  224  when the foot  302  is removed off the ground. 
     FIGS. 7-11  illustrate how the direction of travel of a plurality of swivel ram rollers  100  can be changed.  FIG. 7  illustrates the plurality of swivel ram rollers  100  positioned to travel in a first direction. The hydraulic cylinders  310  of these swivel ram rollers  100  are in the retracted position, such that all of the roller assemblies  220 ,  224  engage the ground. To change the direction of travel of these swivel ram rollers  100 , the hydraulic cylinders  310  are operated until they are in the extended position. The bodies  200  of all of the swivel ram rollers  100  can be rotated to any of various new directions of travel, as shown in  FIGS. 8-11 . Once the swivel ram rollers  100  are aligned in the desired new direction, the hydraulic cylinders  310  are operated to transform the swivel ram rollers  100  to their retracted state. 
   While the invention has been described with reference to various exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments or constructions. To the contrary, the invention is intended to cover various modifications and equivalent arrangements. In addition, while the various elements of the disclosed invention are shown in various combinations and configurations, which are exemplary, other combinations and configurations, including more, less or only a single element, are also within the scope of the invention.