Connector mechanism

Abstract

A connector mechanism for use in an interconnecting, disengageable rack structure. The combination of a novel post configuration and connector plate attached to a load-supporting beam, said post having a front web and opposed side flanges with a central recess formed longitudinally in the web defining a pair of spaced front faces and opposed post corners having apertures formed therein, said connector plate having a pair of spaced flanges joined by a web defining a recess having a width substantially equal to the width of the post faces and at least one projection struck inwardly from a corner of the connector plate defined by the juncture of a flange and the web, whereby the projection enters an aperture and the plate flanges embrace the post walls adjacent a post face upon abutment of the connector plate against a post face.

Description

This invention relates to a connector mechanism and, more particularly, is directed to an improved connector mechanism for use in detachably securing together the component parts of pallet racks, shelf racks, scaffolding and the like structures to form, when assembled, a rigid, interconnected, self-supporting structure which can be quickly and easily disengaged for dismantling for transportation and storage.

Structures such as racks, shelving, scaffolding and the like normally comprise upright truss post assemblies, horizontal beam support members and connecting means for joining the components together. The truss post assemblies usually are fabricated from channel and angle steel members and comprise a pair of vertical columns rigidly secured a spaced distance apart from each other by horizontal and diagonal structural members which are welded or otherwise secured thereto. The truss post assemblies provide rigidity in the vertical plane transverse to the long axis of the structure. At the installation site, horizontal beams are secured to and supported on the upright post assemblies by connecting means such as connector plates with removable locking pins and/or a plurality of bolts, screws, nuts and the like fastening elements. Ancillary members such as cross-braces or locking devices are commonly additionally installed to provide rigidity in the longitudinal plane of the structure.

These conventional constructions heretofore have required the use of bolts or the like separate fastening devices which involve tools maintenance of a substantial inventory of parts and hand tools, and, generally, the employment of at least semi-skilled workmen. Also, the use of ancillary structures, such as locking devices and cross-bracing arrangements, necessary to provide rigidity in the longitudinal plane of the assembled structure, present installation problems. The multiplicity of parts required and/or the installation time required for the proper erection of a rigid and self-supporting structure often increase capital investment and erection costs to prohibitive levels and thereby render available structures uneconomical. It is also apparent that many prior structures are not flexible to the changing requirements of the user.

Many of the foregoing deficiencies inherent in prior structures were overcome by the improved locking mechanism described in U.S. Pat. Nos. 3,048,245 and 3,217,894. The structures of these patents obviated the need for ancillary components such as locking pins while additionally providing the advantages of effectively distributing vertical, torsional and lateral loads such that the pressure loading on unit areas of structural materials were substantially reduced. In addition, the load forces on each post member and connecting plate member were so resolved as to impose tensional stresses on the post and plate materials rather than shear stresses. Therefore, the loading capacity of the structures were substantially increased and safety factors enhanced.

I have now discovered an improved detachable connector structure for use in interconnecting, disengageable structures which provides further enhanced vertical load capacity, torsional and lateral stability and improved load transfer from the load supporting members to the post members. In essence, the detachable connector mechanism of the present invention comprises the combination of a novel post having a front web and opposed side flanges, a recess formed longitudinally centrally in said web defining a pair of spaced front faces and opposed corners at the junctures of the recess side walls and web faces, and apertures formed along at least one of said corners, a load-supporting member, and a connector plate for joining the load-supporting member to the post, said connector plate having a pair of spaced flanges joined by a web defining a recess between said flanges having a width substantially equal to the width of the post web front face, one of said flanges secured to said load-supporting member, a downwardly extending projection struck inwardly from the material of the plate at the bight defined at the juncture of the other plate flange and the plate web, said projection being of a shape to enter the apertures formed in the corners of the post members and to engage the interior walls of the post members by abutment therewith.

It is, therefore, an important object of the present invention to provide a connector mechanism for the facile securing together of structural parts while permiting ready disassembly thereof for transportation and storage.

It is another important object of the present invention to provide an interconnecting, disengageable structure having a connector mechanism which provides quick and easy assembly, combined with improved strength and rigidity of construction, and which can be readily and inexpensively manufactured.

A still further object of the present invention is the provision of a rigid and self-supporting structure with improved vertical, lateral and torsional strength characteristics.

These and other objects of the invention and the manner in which they can be attained will become apparent from the following detailed descrition, reference being had to the accompanying drawing, in which:

FIG. 1 is a perspective view of a rack construction using the connector mechanism of the present invention;

FIG. 2 is a perspective view of a connector mechanism of the present invention showing a beam member laterally separated from a post member preparatory to assembly thereof;

FIG. 3 is a horizontal section, partly in elevation, taken along the line 3 -- 3 of FIG. 4 showing the relationship of connector component parts assembled on a post; and

FIG. 4 is a vertical section, partly in elevation, taken along lines 4 -- 4 of FIG. 3, further showing the assembly of component parts of the connector mechanism mounted on a post.

Referring to the drawings, the numeral 10 designates a vertical steel post of hollow construction having front web designated generally by numeral 12 and opposed side flanges 14, 16. Flanges 14, 16 may be turned along their rear edges, as indicated by numerals 18,20, to provide added rigidity to the flanges. The front web 12 has a longitudinal recess 22 formed centrally therein to define spaced-apart front faces 24, 26, opposed side walls 28, 30 and rear wall 32.

A plurality of equally spaced apertures 34 are formed along each of opposed corners 36, 38 defined by the junctures of front face 24 and side wall 28 and front face 26 and side wall 30 respectively.

Support member 40, shown in FIGS. 1 and 2 as a horizontal beam or stringer, has a connector designated by numeral 42 rigidly secured to each end thereof. Connector 42 is formed from a section of channel steel having spaced, parallel flanges 44,46 and an interconnecting web 48. Connector 42 is secured to the ends of beam 40 by a fillet weld 49 or the like joining means on the outer surface of flange 44 such that flanges 44, 46 are perpendicular to the long axis of said beam 40. A recess 50 is defined between flanges 44,46 having a width substantially equal to the width of front post faces 24,26 whereby the included sides of flanges 44, 46 will abut post flange 14 and recess wall 28, or post flange 16 and recess wall 30, in tight-fitting relationship therebetween. It will be understood that although the description has proceeded with reference to a left-hand connector affixed to the left end of a support member, it is intended for brevity of description to also refer by like numerals throughout the description to a right-hand connector.

A pair of vertically spaced, downwardly extending projections 52 are struck inwardly into the bight defined on the included side of plate web 48 and flange 46. Each of said projections 52 is formed by removing a substantially U-shaped cutout 60 from the material of the connector and then inwardly deforming the resulting projection at its upper connecting portion 62 such that the planes of the outer surfaces of the projection walls 64,66 are displaced inwardly of the planes of the inner surfaces of the connector walls 46, 48 a distance equivalent to the thickness of the post walls, while remaining substantially parallel thereto. Connector 42 may have a single projection 52, or a plurality of projections such as the pair illustrated, or three or more projections spaced a distance apart equal to the spacing of apertures 34, or multiples of the spacing of apertures 34, such that lateral movement of connector 42 results in projections 52 being received in coextensive apertures 34.

In the embodiment shown in FIGS. 1 and 2, a pair of projections 52 are coextensive with a pair of adjacent apertures 34. The spacing of projections 52 is determined by the rigidity and vertical load and torsional load requirements of the horizontal support members 40. The spacing of apertures 34 is determined by the degree of vertical adjustment of horizontal members 40 desired.

In assembling the structure of the invention, a connector 42 is moved laterally into bearing relationship with, for example, face 26 of post 10 such that connector flanges 44, 46 embrace post flange 16 and wall 30 and projections 52 are inserted into aperture 34. The connector is then moved vertically downwardly such that the exterior surfaces of projection walls 64, 66 abut and engage the inner surfaces of post walls 26, 30 and the interior surfaces of connector walls 44, 48 and 46 abut and engage the exterior surfaces of post walls 16, 26 and 30 in tight fitting relationship. This engagement of component parts is shown most clearly in FIGS. 3 and 4 in which a projection 52 is inserted into an aperture 34 in post member 10 and the exterior surfaces of projection walls 64, 66 brought into abutting relationship against the interior surfaces of walls 26, 30. Projection wall 66, which is shown wider than wall 64, resists in shear torsional loads imposed on beam 40 due to the pushing on and dragging off of loads supported on the beams 40, and due to the unbalanced support of heavy loads such as container 80 on lateral stringers 82, shown in FIG. 1, which have been bent by the central vertical load due to impact from the placing and removing of loads from the rack. A wedging action is apparent in FIG. 4 whereby the bevelled portion 62 of the projection, at which the projection is inwardly deformed, engages the lower edge 70 of aperture 34 of the post member. Projection walls 64, 66 of each projection 52 preferably are slightly inwardly deformed at their lower ends, as shown in FIG. 4 for wall 66, to facilitate insertion of projection 52 into aperture 34.

The torsional and lateral loads on the horizontal load supporting members 40 are thus transmitted by way of connectors 42 to post member 10 through the abutting bearing surfaces created by the engagement of the walls of projection 52 with the corresponding walls of the post members 10. Since the loads are transmitted over substantially large bearing surfaces, the loading stresses on the coupling members are minimized, thereby maintaining the structural stresses at a safe working level. Also the torsional and lateral loads are so resolved by the connector mechanism that the structural materials are brought under tension and compression as well as shear, thereby further enhancing the structural load capacities.

In addition, the plurality of spaced locking projections 52 interact to provide an effective counter to vertical and torsional deflections and to force couples exerted on horizontal member 40 due to turning moments resulting from improperly aligned or unbalanced loads on the horizontal member. Also, the pair of spaced locking projections provide added rigidity in the vertical longitudinal plane of the structure.

The vertical load transmitted from member 40 to the post 10 through connector 42 is in proximity to the neutral axes of post 10 and thus minimizes bending moments normally imposed on the post. Stresses created in the connector and post are so resolved by the bevelled portions 62 of each projection 52 that projections 52 will not readily fail by bending when overloaded but rather will cause a metal build-up and work hardening of the roots of the projections to enhance the load capacity of the connector.

FIG. 1 illustrates a pallet rack assembly consisting of upright spaced truss post constructions 75 and interconnecting beams 40 joined thereto by connectors 42. A beam 40 is shown separated laterally from the rack prior to assembly. Each truss post construction comprises two vertical posts 10 and horizontal and diagonal channels 76 and 77 which are rigidly secured to the posts by welding or the like means. Thus, the truss post construction provides rigidity in the transverse plane taken at right angles to the long axis of the structure. The plurality of beams 40 secured as indicated to the sides of the rack provides a longitudinal rigidity to obviate the need for diagonal reinforcing members.

Tests conducted on the post of the present invention compared to the structure of the assembly disclosed in U.S. Pat. No. 3,217,894, using the same amount of cross-sectional steel material, and by load-testing to destruction, provided the following results.

______________________________________ LOADING CONDITION PRESENT POST PRIOR ART POST ______________________________________ Axial Load 28,400 lb. 22,800 lb. Load on centre line bet- ween apertures and outside edge of post 26,500 lb. 16,300 lb. Load on corner of one of the apertures 20,800 lb. 10,000 lb. Flexure perpendicular to the side of assembled rack 23,700 in.-lb. 18,750 in.-lb. ______________________________________

Post properties such as the net section modulus in the strong axis have been increased in excess of 30 percent with no increase in steel and it will be noted from the above data that the load capacities of the posts of the present invention are substantially increased, relative to the prior art post. The flexural capacity of the present post is indicated to be more than 25 percent higher than the prior art post, thereby providing greater resistance to accidental damage caused by impact from loading vehicles such as fork-lift trucks.

It will be understood, of course, that modifications can be made in the preferred embodiment of the present invention as described hereinabove without departing from the scope and purview of the appended claims.

Claims

What we claim as new and desire to protect by Letters Patent of the United States is:

1. A connector for detachably securing a load-supporting member to a post having a front web and opposed side flanges, a continuous recess formed longitudinally centrally in said web defining a pair of spaced front faces and opposed side walls adjacent said front faces, said spaced front faces and opposed side walls forming a pair of opposed corners, and vertical apertures formed along at least one of said opposed corners, comprising: a connector plate having a pair of spaced, substantially parallel flanges joined by a web defining a recess between said flanges having a width substantially equal to the width of a web front face, one of said flanges secured to said load-supporting member, a downwardly extending projection struck inwardly from the material of the plate at the bight defined at the juncture of the other plate flange and the plate web, said projection being of a shape to enter an aperture formed in a said corner of the post member and to engage the interior walls of the post member by abutment therewith.

2. A connector as claimed in claim 1, in which said load-supporting member is a horizontal beam.

3. A connector as claimed in claim 2, in which said projection has a pair of walls substantially perpendicular to each other and parallel to the opposed walls of the post member with which the projection is in abutment.

4. A connector as claimed in claims 3, in which said projection walls are continuously joined to the plate walls by a bevelled corner portion.

5. A connector as claimed in claims 3, in which said projection walls are continuously joined to the plate walls by a bevelled corner portion and the projection wall perpendicular to the axis of the load-supporting member is of increased width for shear resistance.

6. An interconnecting disengageable structure comprising a post having a front web and opposed side flanges, a continuous recess formed longitudinally centrally in said web defining a pair of spaced web front faces and opposed side walls adjacent said front faces, said spaced front faces and opposed side walls forming a pair of opposed corners, and vertical apertures formed along at least one of said opposed corners, a connector plate having a pair of spaced, substantially parallel flanges joined by a web defining a recess between said flanges having a width substantially equal to the width of a web front face, one of said flanges secured to said load-supporting member, a downwardly extending projection struck inwardly from the material of the plate at the bight defined at the juncture of the other plate flange and the plate web, said projection being of a shape to enter an aperture formed in a said corner of the post member and to engage the interior walls of the post member by abutment therewith.

7. An interconnecting disengageable structure as claimed in claim 6, in which said load-supporting member is a horizontal beam.

8. An interconnecting disengageable structure as claimed in claim 7, in which said projection has a pair of walls substantially perpendicular to each other and parallel to the opposed walls of the post member with which the projection is in abutment.

9. An interconnecting disengageable structure as claimed in claim 8 in which said projection walls are continuously joined to the plate walls by a bevelled corner portion.

10. An interconnecting disengageable structure as claimed in claim 8, in which said projection walls are continuously joined to the plate walls by a bevelled corner portion and the projection wall perpendicular to the axis of the load-supporting member is of increased width for shear resistance.

11. A connector as claimed in claim 3, in which said projection walls are slightly inwardly deformed at their lower ends.

12. A connector as claimed in claim 8, in which said projection walls are slightly inwardly deformed at their lower ends.