The present invention is generally directed to the field of jib cranes. In particular, the present invention is directed to a crane having both tension and compression supports, arranged for rotation of a crane boom about a support pole or post.
Cranes, hoists and other various lifting arrangements are found in a wide variety of sizes and configurations. A key determinant in the size and configuration of a crane or other lifting device is the size and configuration of the load to be handled. Within the constraints dictated by load size, the overall environment in which the crane is placed will also be an important determinant in selecting the crane configuration and its support arrangements.
Since cranes, especially those used in building construction, are generally temporary structures, applied to carry out a specific job, the mobility and ease of assembly of the crane system is an important factor in the selection and application of the particular crane. Likewise, ease of operation is critical, especially if time constraints are determined by the environment or the job to be done.
Accordingly, there is always a need for efficient crane installation and easy operation.
It is a primary object of the present invention to provide a crane system that is strong, stable, easy to install, and flexible in operate. The crane system must be compact, with a small yet sturdy support footprint.
It is another object of the present invention to provide a crane system with a jib boom that is easy to rotate in a 360° arc, with or without a load.
It is a further object of the present invention to provide a crane system that is easily mounted in a wide variety of different environments, including concrete pads and steel platforms.
It is again another object of the present invention to provide a substrate interface-support particularly configured for a crane system having a cylindrical vertical pole.
It is an additional object of the present invention to provide a crane system with a simple compact internal support arrangement, having the advantages of both a compression type boom support and a tension type boom support.
It is still another object of the present invention to provide a jib crane configuration that can be easily scaled for accommodating different load ranges and environments.
It is again an additional object of the present invention to provide a crane system which requires minimal support from the environment in which the crane is placed.
It is still another object of the present invention to provide a crane system having a boom which is freely rotatable, without sacrificing strength and stability when under load.
It is yet a further object of the present invention to provide a crane system in which smoothness of boom rotation is facilitated by easy leveling of the crane's vertical support with respect to the foundational support and substrate.
It is still another object of the present invention to provide a crane system that accommodates and/or works with a wide variety of substrate interface-supports.
It is again a further object of the present invention to provide a crane system that uses the counter-balance between compression and tension to improve lifting strength and durability over conventional cranes.
It is yet a further object of the present invention to provide a crane system with a rotating boom arranged in a manner so that destructive lateral stresses, including shear forces and bending moments, are transferred from the pivot point at the rotating boom and vertical pole, to the pole length.
It is still an additional object of the present invention to provide a crane system that minimizes environmental constraints on the assembly and operation of the crane.
These and other goals and objects of the present invention are achieved by an interconnected boom support system having a cylindrical post or pole for lifting, carrying, and setting down a load. The pole has an outer surface and a length with an upper segment. A pivot structure is preferably arranged at the upper segment of the pole to accommodate a boom for lifting a load. The boom is rotatably secured to the pivot structure at a pivot point along the length of the boom, thereby dividing the boom into first and second portions. A compression support extends from the underside of the first portion of the boom to a compression roller engagement assembly positioned for rotatable engagement at the outer surface of the cylindrical pole. A tension roller engagement assembly is secured to the second portion of the boom and is also positioned for rotatable engagement around the outer surface of the cylindrical pole, opposite the compression roller engagement assembly. A tension frame extends from the tension roller engagement assembly to the compression roller engagement assembly. As a result, the compression support, compression roller engagement assembly, tension frame and second portion of the boom is arranged to provide structural support and counterbalancing for lifting the load. The pivot structure at the upper segment of the cylindrical pole, the compression roller engagement assembly and the tension roller engagement assembly facilitate easy rotation of the load around the support pole.
The drawings included herewith are for the purpose of illustration only and not as a definition of the limits of the instant invention, for which reference should be made to the claims appended hereto. Other features, objects and advantages of this invention will become clear from the following more detailed description made with reference to the drawings in which:
The following descriptions depict only example embodiments and are not to be considered limiting of its scope. Any reference herein to “the invention” is not intended to restrict or limit the invention to exact features of any one or more of the exemplary embodiments disclosed in the present specification. Reference to “one embodiment,” “an embodiment,” “various embodiments,” and the like, may indicate that the embodiment(s) so described may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Further, repeated use of the phrase “in one embodiment,” or “in an embodiment,” do not necessarily refer to the same embodiment, although they may.
Accordingly, the particular arrangements disclosed herein are meant to be illustrative only and not limiting as to the scope of the invention, which is to be given the full breadth of the appended claims and any and all equivalents thereof. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. Unless otherwise expressly defined herein, such terms are intended to be given their broad ordinary and customary meaning not inconsistent with that applicable in the relevant industry and without restriction to any specific embodiment hereinafter described. As used herein, the article “a” is intended to include one or more items. When used to join a list of items, the term “or” denotes at least one of the items but does not exclude a plurality of items of the list.
In this case, the present disclosure is directed to a jib crane assembly 10. Jib crane assemblies of this type typically include vertical support provided by a post or pole 11, which is preferably constituted by a hollow steel cylinder. However, the vertical pole 11 can be made of other materials and/or can be a solid cross-sectional support. The pole 11 includes a lower base portion 12 with a substrate interface-support arrangement 20 having support fins 17 and a pole bearing plate 19 for providing support for the overall jib assembly 10 (via a necessary connection to the foundational substrate).
A boom 18 of the jib crane assembly 10 is preferably an I-beam 89, with a top flange or plate 88, as seen in
The boom 18 engages the vertical pole 11 at pivot arrangement 16, which allows easy pivoting of the boom in a 360° arc. Easy rotation of boom 18 is facilitated by the essentially “free-floating” pivot arrangement 16 (depicted in
The present invention combines two types of support used in a novel manner to counter-balance the load being lifted to opposite sides of the pole 11, away from the pivot arrangement 16. A compression assembly for boom 18 is provided by means of compression support 13 seen in
The forces developed at the interface of compression roller assembly 31 and the surface of pole 11 are further distributed by tension arms 40, which extend from receiving frame 38 (to secure via attachment end-plate portions 44) to corresponding tension arm connection brackets 87. Brackets 87 flank and secure to vertical connector 84. Vertical connector 84 supports tension roller assembly 81 by means of a tension roller yoke 82, as seen in
To be clear, the vertical connector 84 connects the tension roller assembly 81 (held by roller yoke 82) at the end of boom 18. As a result, the compression support 13, attached to the first section of the boom 18, is also supported in part by the end of the second section of boom 18, thereby helping to balance the load about the pivot arrangement 16. Accordingly, stresses are transmitted through tension arms 40 and transferred into lateral forces by the pressure of the tension roller assembly 81 against pole 11, beneath the pivot assembly 16. In addition to the distributing forces developed from compression support 13 and tension frame 14, vertical connector 84 serves to provide added weight to the end of the second section of the boom 18, thereby facilitating a counterbalance to the weight of the first section of the boom 19.
Also connected to vertical connector 84 is cover plate 90, which helps secure a connection between the beam 89 and vertical connector 84. Depending upon the exact configuration of beam 89, cover plate 90 can serve to stiffen the overall structure of boom 18. In addition, the cover plate 90 can serve to provide a covered platform for electrical lines, cables, pulleys and winching devices that are necessary when using the jib crane assembly 10 in its particular mechanical and functional configuration (e.g. manual versus electric hoist, with or without select hand controls, etc.). Though these features are not depicted in the drawings as part of the present invention, they are still essential to select hoist operational designs.
The second section (the shorter part of the boom 18 as divided by pivot assembly 16) provides support for tension roller assembly 81 (held by roller yoke 82 depicted in detail in
With reference to
Vertical alignment tabs 61 on the top side of cap 60 are used to confine therebetween a boom rocker-seat 85 welded to the bottom flange or plate of I-beam 89 to hold the I-beam 89 in place, preventing lateral movement during operation between vertical alignment tabs 61 at pivot assembly 16. The boom rocker-seat 85 can be a solid metal-piece having a semi-circular cross-section or arched curvature with a length slightly less than the space “D” between alignment tabs 61 for fitted positioning therebetween, as best seen with reference to
As previously described, the freely rotating pivoting assembly 16 in the instant invention balances the boom 18 on top of pole 11 by dividing the boom 18 into first and second sections. The balancing at the pivoting assembly 16 is accomplished using the weight of vertical connector 84 in conjunction with the interconnecting configuration of the support structure, namely the compression support 13 and tension frame 14. The balance achieved thereby is determinative of the ease of rotation of the entire boom and interconnected support structure as a unit. It should be noted that the pivoting assembly 16 depicted in
It is noted that pivoting assembly 16 rests on top of pole 11 by the weight of boom 18. Lateral forces, otherwise at the pivoting assembly 16, have been transferred by the novel interconnected support structure constituted by the vertical connector 84, tension roller assembly 81, tension arms 40, compression roller assembly 31, and the rest of compression support 13, along with its connection to beam 89 is bracket 86. The result is a highly desirable ease of rotation of the boom 18 (along with all the supporting elements), even with a load at the distal end of I-beam 89.
Free rotation of the boom 18 of the jib crane assembly 10 about pole 11 is facilitated because the support system (compression support 13 and tension frame 14) is entirely self-contained, using only pole 11 to transfer stresses caused by forces at the end of beam 89. Since the subject support system does not have to rely upon external connections to the environment (as is very common with many tension support arrangements used to balance heavy boom loads), the overall footprint of the inventive jib crane assembly 10 is much reduced over that of many conventional lifting systems. Also, since there are no additional external connections are needed to help maintain boom support, 360° rotation of the boom is easily facilitated in smaller work spaces. Further yet, since the second (i.e., shorter) portion of the boom, more easily avoids rotation obstructions, use of the instant jib crane assembly 10 in a confined space is easily facilitated.
The simple design of the instant jib crane assembly 10 allows easy scaling to fit various environments and duty cycles. Accordingly, the compact support arrangement of the inventive jib crane assembly 10 can require mounting in a relatively small area, thereby requiring a novel substrate anchoring support-interface arrangement 20. To be clear, the instant invention creates a need for an innovative anchoring system for mounting the pole 11 to a surface such as new concrete or an existing foundation having varied strengths and depths.
The pole support bracket 21 depicted in
A variation of the pole support bracket 21 shown in
It should be understood that the aforementioned embodiments for the substrate interface-support structural arrangements 20, 21 (illustrated in
Accordingly, the present invention can be embodied by devices of a substantial number of different sizes and load types. The type of substrate interface-support arrangement can vary based upon the nature of the utility, space requirements, substrate and the loads to be handled. Further, the present invention need not be fixed. For example, the jib crane assembly 10 of the present invention can be mounted on a wheeled trolley, such as those used for hoisting automobile engines from a vehicle. All that matters is that sufficient width of the trolley be provided to accommodate the lifting duties of the selected jib crane assembly 10. The actual substrate interface-support arrangement or mounting system can be left up to the particular application in which the present invention is to be used.
While preferred embodiments, and multiple variations thereof, have been described by way of example, the present invention is not limited thereto. rather, the present invention should be interpreted to include any and all variations, adaptations, permutations, and derivations that would occur to one skilled in this art, and in possession of the teachings of the present invention. Accordingly, the present invention should be limited only by the following claims.