Swivel ram roller

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.

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'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.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Referring now in detail to the drawings, there is illustrated, inFIGS. 1-6, a swivel ram roller of one embodiment of the invention.

Specifically,FIGS. 1-6show a swivel ram roller100with a body200and a lifting mechanism300. As shown inFIGS. 1-3, the body200includes a top wall202, side walls204,206,208and210, roller assemblies220,224, axle assemblies222,226for the roller assemblies220,224and tabs230,232. The top wall202is located on top of and connects the side walls204,206,208and210(the respective ends of the side walls204,206,208and210may also be connected). The tabs230,232are located on an outside surface of the side walls206,208and include an opening. The tabs230,232can be engaged by a hook, rope, chain, cable or other mechanism to move the swivel ram roller100.

The roller assemblies220,224are located within the side walls204,206,208and210and below the top wall202. As shown, the roller assemblies220,224are chain roller assemblies which are rotatable about the axle assemblies222,226, respectively. The axle assemblies222,226are attached to the side walls204,210. Roller assemblies such as roller assemblies220,224and axle assemblies such as axle assemblies222,226are common and well known in the industry, and thus are not described in detail. The roller assemblies220,224rotate in two directions, clockwise and counterclockwise, from the perspective ofFIG. 3, such that the swivel ram roller100can move in opposite directions120,122. In other embodiments, the roller assembly can be a wheel with a central axle attached to the side walls204,210, 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 roller100can be utilized.

The body200also includes internal walls212,214which are between the roller assemblies220,224and the lifting mechanism300, and below the top wall202. The internal walls212,214extend between and are connected on their ends to the side walls204,210. Internal walls212,214partially house the lifting mechanism300to prevent large debris from contacting the lifting mechanism300. As should be appreciated, any suitable wall, divider or shield can be used to prevent large debris from contacting or interfering with the lifting mechanism300. In yet other embodiments, such walls, dividers or shields can be omitted.

As shown inFIGS. 3-6, the lifting mechanism300includes, from bottom to top, a foot302, nuts304,306, a lift ring308, a hydraulic cylinder310, a swivel disk320and a top plate330. The top of the foot302is attached to or integral with the bottom of the hydraulic cylinder310. As shown inFIG. 3, the foot302is positioned a predetermined distance away from the ground when the lifting mechanism300is in the retracted position so that the foot302does not interfere with the movement of the swivel ram roller100.

The nuts304,306are attached to or integral with an outer surface of the hydraulic cylinder310above the foot302. The nuts304,306attach the lift ring308to the hydraulic cylinder310. 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 ring308to the hydraulic cylinder310. As should also be appreciated, the nuts304,306or other retaining device, lift ring308and hydraulic cylinder310can be formed as one unit capable of supporting and lifting the body200and a load, as discussed below.

As shown inFIGS. 3 and 4, the top surface of lift ring308is a predetermined distance340below the bottom surface of the top wall202when the hydraulic cylinder310is in the retracted position. As also shown inFIGS. 3 and 4, the lift ring308surrounds the entire outer surface of the hydraulic cylinder310. However, as should be appreciated, the lift ring308can obviously partially surround the outer surface of the hydraulic cylinder310, or can be replaced by fingers, flanges or other structural members which can selectively engage the top wall202, as discussed below.

As shown inFIG. 4, the top part of the hydraulic cylinder310extends above the top wall202. A hydraulic connection312, located in the swivel disk320, is connected to the hydraulic cylinder310above the top wall202. Hydraulic fluid is received from a hydraulic source400(FIGS. 7-11), through the hydraulic connection312, by the hydraulic cylinder310to increase the hydraulic pressure in the hydraulic cylinder310. Conversely, hydraulic fluid is returned to the hydraulic source400, through the hydraulic connection312, from the hydraulic cylinder310to reduce the hydraulic pressure in the hydraulic cylinder310. As should be appreciated, the hydraulic cylinder310can 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 cylinder310can be a single acting or a double acting cylinder. If the hydraulic cylinder310is a double acting cylinder, two hydraulic connections312are located in swivel disk320. 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 disk320is attached to or integral with the top part of the hydraulic cylinder310. The swivel disk320covers the top of the hydraulic cylinder310. As shown inFIGS. 3 and 4, the swivel disk320includes a side wall322that extends to the top of the top wall202when the hydraulic cylinder310is in the retracted position. In other words, as shown inFIG. 4, the swivel disk320covers the top of the hydraulic cylinder310and is in contact with the top wall202when the hydraulic cylinder310is in the retracted position.

When the hydraulic cylinder310is in the retracted position, the foot302is a predetermined distance above the ground. Specifically, as discussed, the swivel disk320is attached to or integral with the top of hydraulic cylinder310and the foot302is attached to, or integral with the bottom of hydraulic cylinder310. Thus, when the hydraulic cylinder310is in the retracted position, the swivel disk320is supported by the top wall202, and the foot302is maintained a predetermined distance above the ground by the hydraulic cylinder310.

The swivel disk320also includes a plurality of projections324that extend downwardly from the bottom surface of the swivel disk320. The plurality of projections324match and are received by a plurality of detents220that are formed in the top surface of the top wall202. The plurality of projections324are received in the plurality of detents220in order to prevent the lifting mechanism300from rotating independently relative to the body200when the lifting mechanism300is in the retracted position. In other embodiments, the plurality of projections extends upwardly from the top of the top wall202and are received by a plurality of detents in the bottom surface of the swivel disk320. 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 mechanism300relative to the body200when the lifting mechanism300is in the retracted position.

The top plate330is attached to or integral with the top of the swivel disk320. The top plate330is placed on top of the swivel disk320to receive a load. As should be appreciated, any load receiving structure can be placed on top of or otherwise attached to the swivel disk320. In other embodiments, the load receiving structure is omitted and loads are thus placed directly on the swivel disk320.

As shown inFIGS. 3 and 4, when a load is placed on the top plate330with the swivel ram roller in the retracted state, the force due to the load is transmitted from the top plate330to the swivel disk320, to the body200, and to the roller assemblies220,224, Also, the swivel disk320remains in a fixed rotational position with respect to the body200because the projections324of the swivel disk320engage the detents220in the top plate202.

A description will now be provided of the transformation of the swivel ram roller100from a retracted state, as shown inFIGS. 3 and 4, to an extended state, as shown inFIGS. 5 and 6. Hydraulic fluid is passed to the hydraulic cylinder310from the hydraulic source400, via the hydraulic connection312, to increase the hydraulic pressure in the hydraulic cylinder310. When the hydraulic pressure is sufficiently increased, the hydraulic cylinder310initially extends downward until the foot302contacts the ground. When the foot302contacts the ground, the force due to the load switches to be borned by the hydraulic cylinder310and foot302instead of the body200and the roller assemblies220,224.

After the foot302contacts the ground, a further increase in the hydraulic pressure causes the hydraulic cylinder310to extend upward. When the hydraulic cylinder310first extends upward, only the swivel disk320and the top plate330are moved upward with the hydraulic cylinder310. In other words, the body200is not moved upward when the hydraulic cylinder310first extends upward. As should be appreciated, when the swivel disk320and the top plate330initially move upward, the force due to the load is entirely transferred from the swivel disk320to the hydraulic cylinder310and the foot302. In other words, the force due to the load is no longer borne by the body200and the roller assemblies220,224.

The swivel disk320and the top plate330first move upward with the hydraulic cylinder310by the predetermined distance340. As discussed, during this movement, only the swivel disk320and the top plate330move upwardly with the hydraulic cylinder310. As also discussed above, the predetermined distance340is the distance between the top of the lift ring308and the bottom of the top wall202when the swivel ram roller100is in the retracted position. As shown inFIGS. 5 and 6, this movement of the swivel disk320and the top plate330relative to the body200creates a gap342between the top of the top wall202and the bottom of the swivel disk320. In other words, when the hydraulic cylinder310moves upward and the distance between the top of the lift ring308and the bottom of the top wall202becomes shorter, the distance between the top of the top wall202and the bottom of the swivel disk320becomes larger. As should be appreciated, when the bottom of the swivel disk320is spaced from the top of top wall202by the gap342, the projections324at the bottom of the swivel disk320are disengaged from the detents220located on the top surface of the top wall202. The body200can rotate relative to the swivel disk320when the projections324are disengaged from the detents220.

After the top of the lift ring308comes into contact with the bottom of the top wall202and the hydraulic pressure in the hydraulic cylinder310continues to increase, the hydraulic cylinder310further extends upward. During this movement, the lift ring308(which is attached to the hydraulic cylinder310) moves the body200upward. As shown inFIGS. 5 and 6, the body200, including the roller assemblies220,224, are thus lifted off of the ground.

When the body200is lifted off the ground, the body200of the swivel ram roller100can be rotated around the lifting mechanism300. The lifting mechanism300remains stationary as the body200rotates around it. When an operator rotates the body200about the axis124, the operator only has to overcome frictional forces that are created by the load of the body200on the lift ring308. The operator does not have to overcome the force of the load placed on the top plate330.

In various embodiments, the body200is manually rotated about an axis124of the lifting mechanism300(seeFIG. 5). However, as should be appreciated, the body200can be rotated relative to the lifting mechanism300by any device currently available or later developed which can perform this function.

As discussed, the projections322of the swivel disk320match and are received by the detents220of the top wall202. As such, the body200can be rotated to any one of a plurality of positions as long the projections322align with the detents220when the lifting mechanism300is in the retracted position.

A description will now be provided of the transformation of the swivel ram roller100from the extended state, as shown inFIGS. 5 and 6, to the retracted state, as shown inFIGS. 3 and 4. When the hydraulic fluid is initially returned to the hydraulic source400, thus reducing the hydraulic pressure in the hydraulic cylinder310, the hydraulic cylinder310, the body200, the swivel disk320and the top plate330move downward until the roller assemblies220,224contact the ground. Continued reduction in the hydraulic pressure in the hydraulic cylinder310causes the hydraulic cylinder310, the swivel disk320and the top plate330to move downward by the height of gap342such that the projections324are received and engaged by the detents220. When the projections324are engaged by the detents220, the lifting mechanism300and the body200are placed in a fixed rotational position. Also, when the lifting mechanism300moves downward by the height of the gap342, the predetermined distance340is created between the top of the lift ring308and the bottom of top wall202.

When the hydraulic pressure in the hydraulic cylinder310is further reduced, the foot302is lifted from the ground. As should be appreciated, the force applied by the load on the top plate330is transferred from the hydraulic cylinder310and the foot302to the body200and the roller assemblies220,224when the foot302is removed off the ground.

FIGS. 7-11illustrate how the direction of travel of a plurality of swivel ram rollers100can be changed.FIG. 7illustrates the plurality of swivel ram rollers100positioned to travel in a first direction. The hydraulic cylinders310of these swivel ram rollers100are in the retracted position, such that all of the roller assemblies220,224engage the ground. To change the direction of travel of these swivel ram rollers100, the hydraulic cylinders310are operated until they are in the extended position. The bodies200of all of the swivel ram rollers100can be rotated to any of various new directions of travel, as shown inFIGS. 8-11. Once the swivel ram rollers100are aligned in the desired new direction, the hydraulic cylinders310are operated to transform the swivel ram rollers100to their retracted state.