Title:
Reduced eccentricity guardrail post connector for decking structure
Kind Code:
A1


Abstract:
A reduced eccentricity guardrail post connector is provided and includes a connection element having a tensile force resistant portion and a shear resistant portion, where a proximal end of the shear resistant portion is connected at about a normal angle to a distal end of the tensile force resistant portion. The post connector further includes a post coupler disposed at a proximal end of the tensile force resistant portion, where the post coupler compressively joins a post to a rim joist. Additionally, a joist coupler is disposed at a distal end of the shear resistant portion, where the joist coupler compressively joins the connector element to a joist. Further, a joist material strengthening element is disposed into the joist to resist tensile loads in joist material. The tensile resistant portion resists tensile loads and the shear resistant portion resist shear loads when the horizontal forces are imparted on the post.



Inventors:
Vayghn, William B. (Lafayette, CA, US)
Application Number:
12/284914
Publication Date:
10/15/2009
Filing Date:
09/26/2008
Primary Class:
Other Classes:
52/698, 52/745.21
International Classes:
E04B1/38
View Patent Images:



Primary Examiner:
HIJAZ, OMAR F
Attorney, Agent or Firm:
JAMES E. PARRIS (HAILEY, ID, US)
Claims:
What is claimed:

1. A reduced eccentricity moment guardrail post connector comprising: a. a guardrail post; b. a rim joist; c. a joist, wherein said rim joist is disposed perpendicularly at an end of said joist, wherein said guardrail post is disposed perpendicularly on said rim joist and perpendicularly to said joist: d. a connection element, wherein said connection element comprises a tensile force resistant portion and at least one shear resistant portion, wherein said tensile force resistant portion is connected at about a normal angle to al said shear force resistant portion, wherein said shear force resistant portion is disposed through said joist and compressively couples said tensile force resistant portion adjacent to said joist providing a reduced eccentricity moment between said tensile force resistant portion and said joist, wherein said tensile force resistant portion extends through said rim joist and said guardrail post and compressively couples said guardrail post to said rim joist, wherein said tensile force resistant portion disposed along said joist, e. a guardrail post coupler, wherein said post coupler is disposed at a proximal end of said tensile force resistant portion, wherein said guardrail post coupler provides said compressive joining of said guardrail post to said rim joist; f. a joist coupler, wherein said joist coupler is disposed at a distal end of said shear resistant portion, wherein said joist coupler provides said compressive joining of said connector element to a joist; and g. a joist material strengthening element, wherein said joist material strengthening element is disposed into said joist at an angle about parallel with said guardrail post, wherein said tensile force resistant portion resists tensile loads when horizontal forces are imparted on said guardrail post, wherein said shear resistant portion resist shear forces when said horizontal forces are imparted on said post, wherein said material strengthening element resist tensile loads in said joist.

2. The guardrail post connector of claim 1, wherein said connection element comprises an angled rod, wherein said tensile force resistant portion comprises a proximal portion of said angled rod and said shear force resistant portion comprises a distal portion of said angled rod.

3. The guardrail post connector of claim 2, wherein said shear resistant portion further comprises a joist sleeve, wherein said distal portion of said angled rod is disposed through said joist sleeve and said joist sleeve is disposed through said joist.

4. The guardrail post connector of claim 3 wherein said joist sleeve comprises a tube, wherein said tube comprises a fillet feature inside said tube, wherein said fillet feature conforms to a bend in said angled rod.

5. The guardrail post connector of claim 1, wherein said connection element comprises: a. an angled plate, wherein said angled plate comprises said tensile force resistant portion and a rim joist abutting portion, wherein a proximal end of said tensile force resistant portion is disposed at about a normal angle to said rim joist abutting portion: b. at least one shear bolt hole disposed near a distal end of said tensile force resistant plate and through said tensile force resistant portion; c. at least one shear bolt disposed through said shear bolt hole and through said joist, wherein said tensile force resistant portion is compressively coupled to said joist by a nut and washer threadably tightened to said shear bolt; d. a tensile rod channel disposed in said proximal end of said tensile force resistant portion and through said rim joist abutting portion; e. a tensile force resistant rod, wherein said tensile force resistant rod is fixedly attached along said tensile rod channel providing a reduced eccentricity moment between said tensile force resistant portion and said joist and extends through said rim joist and said guardrail post for said compressive connection.

6. The guardrail post connector of claim 5, wherein said tensile force resistant rod is fixedly attached to said tensile rod channel using connectors selected from a group consisting of welding, treads to nut, and threads to welded threaded element.

7. The guardrail post connector of claim 1, wherein said connection element comprises: a. a first flat plate, wherein said first flat plate is said tensile force resistant portion comprising a tensile force resistant rod channel disposed in a proximal end of said first flat plate and at least one shear bolt through hole disposed in a distal end of said first flat plate: b. a second flat plate wherein said second flat plate is a rim joist abutting portion; c. a tensile force resistant rod, wherein a distal end of said tensile force resistant rod is fixedly attached to said tensile force resistant rod channel and said second flat plate is disposed at a normal angle along said tensile force resistant rod and at a normal angle to said first flat plate; and d. at least one shear bolt, wherein said shear bolt is disposed through said shear bolt through-hole and through said joist, wherein said tensile force resistant portion is compressively coupled to said joist by a nut and washer threadably tightened to said shear bolt, wherein a proximal end of said tensile force resistant rod extends through said rim joist and through said guardrail post, wherein said guardrail post is compressively coupled to said rim joist by said guardrail post coupler.

8. The guardrail post connector of claim 1, wherein said guardrail post coupler comprises a nut and washer, wherein said nut fixedly attaches to threads of said tensile force resistant proximal end, wherein said nut fixedly compresses said washer to said post, whereby compressively joining said post to said rim joist.

9. The guardrail post connector of claim 1, wherein said joist coupler comprises a nut and washer, wherein said nut fixedly attaches to threads of a distal end of said shear resistant portion, wherein said nut fixedly compresses said washer to said joist, whereby compressively joining said post to said joist.

10. The guardrail post connector of claim 1, wherein said joist material strengthening element is selected from a group consisting of a threaded screw and a nail, wherein said joist material strengthening element binds said joist material to prevent splitting of said joist material.

11. A method of using reduced eccentricity moment guardrail post connector comprising: a. providing a deck, wherein said deck comprise at least a deck floor, a deck rim joist and a joist, wherein said rim joist is disposed perpendicularly at an end of said joist, wherein said guardrail post is disposed perpendicularly on said rim joist and perpendicularly to said joist; b. providing at least one post for attaching to said rim joist; c. providing a connection element, wherein said connection element comprises a tensile force resistant portion and at least one shear resistant portion, wherein said tensile force resistant portion is connected at about a normal angle to a said shear force resistant portion, wherein said shear force resistant portion is disposed through said joist and compressively couples said tensile force resistant portion adjacent to said joist providing a reduced eccentricity moment between said tensile force resistant portion and said joist, wherein said tensile force resistant portion extends through said rim joist and said guardrail post and compressively couples said guardrail post to said rim joist, wherein said tensile force resistant portion disposed along said joist; d. providing a guardrail post coupler, wherein said post coupler is disposed at a proximal end of said tensile force resistant portion, wherein said guardrail post coupler provides said compressive joining of said guardrail post to said rim joist; e. providing a joist coupler, wherein said joist coupler is disposed at a distal end of said shear resistant portion, wherein said joist coupler provides said compressive joining of said connector element to a joist; and f. providing a joist material strengthening element, wherein said joist material strengthening element is disposed into said joist at an angle about parallel with said guardrail post, wherein said tensile force resistant portion resists tensile loads when horizontal forces are imparted on said guardrail post, wherein said shear resistant portion resist shear forces when said horizontal forces are imparted on said post, wherein said material strengthening element resist tensile loads in said joist.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is cross-referenced to and claims the benefit from U.S. Provisional Patent Application 60/995,165 filed Sep. 26, 2007, which is hereby incorporated by reference.

FIELD OF THE INVENTION

The invention relates generally to a guardrail post connection. More particularly, the invention relates to securing a railing post to a deck base in a manner that provides both shear and tension strength to the post, while enabling easy and correct installation.

BACKGROUND

Building codes require guardrail posts to resist 200 pounds at the top of the post in all directions with a safety factor of 2.5. The typical connections used to connect guardrail posts to wood framed decks fail to meet this requirement, according to published test results for a 36-inch post length. Current codes in many states now require the post connections pass a minimum 200-pound resistance test for a 42″ post length.

One significant defect in guardrail post connectors that integrate both a rim joist and a joist to the post is the presence of an eccentric moment between the connector and the joist. A tensile load resistant component that is displaced from the connection to the joist creates an eccentric moment in the connection that limits the strength of the connection. Failure of the guardrail post and thereby guardrails have resulted in injuries and death.

Accordingly, there is a need to develop a guardrail post connection that reduces or eliminates eccentric moments between the tensile force resistant section and the coupling at the joist, and enables easy and correct assembly of deck railing posts to a deck base while supplying substantial support

SUMMARY OF THE INVENTION

To overcome the shortcomings in the art, reduced eccentricity moment guardrail post connector is provided. The reduced eccentricity moment guardrail post connector includes a guardrail post, a rim joist, a joist disposed perpendicularly at an end of the joist, where the guardrail post is disposed perpendicularly on the rim joist and perpendicularly to the joist. The invention further includes a connection element having a tensile force resistant portion and at least one shear resistant portion, where the tensile force resistant portion is connected at about a normal angle to a the shear force resistant portion, and the shear force resistant portion is disposed through the joist and compressively couples the tensile force resistant portion adjacent to the joist providing a reduced eccentricity moment between the tensile force resistant portion and the joist. Additionally, the tensile force resistant portion extends through the rim joist and the guardrail post and compressively couples the guardrail post to the rim joist and the tensile force resistant portion disposed along the joist. The reduced eccentric moment connector further includes a guardrail post coupler disposed at a proximal end of the tensile force resistant portion, where the guardrail post coupler provides the compressive joining of the guardrail post to the rim joist. A joist coupler is disposed at a distal end of the shear resistant portion, and provides the compressive joining of the connector element to a joist. A joist material strengthening element is disposed into the joist at an angle about parallel with the guardrail post, where the tensile force resistant portion resists tensile loads when horizontal forces are imparted on the guardrail post, the shear resistant portion resist shear forces when the horizontal forces are imparted on the post, and the material strengthening element resist tensile loads in the joist.

In one embodiment of the invention, the connection element includes an angled rod, where the tensile force resistant portion is a proximal portion of the angled rod and the shear force resistant portion is a distal portion of the angled rod. In this embodiment, the shear resistant portion further includes a joist sleeve, where the distal portion of the angled rod is disposed through the joist sleeve and the joist sleeve is disposed through the joist. The joist sleeve can be a tube having a fillet feature inside the tube, where the fillet feature conforms to a bend in the angled rod.

In another embodiment of the invention, the connection element is an angled plate having the tensile force resistant portion and a rim joist abutting portion, where a proximal end of the tensile force resistant portion is disposed at about a normal angle to the rim joist abutting portion. The current embodiment further includes at least one shear bolt hole disposed near a distal end of the tensile force resistant plate and through the tensile force resistant portion. At least one shear bolt is disposed through the shear bolt hole and through the joist, where the tensile force resistant portion is compressively coupled to the joist by a nut and washer threadably tightened to the shear bolt. A tensile rod channel is disposed in the proximal end of the tensile force resistant portion and through the rim joist abutting portion. Additionally, a tensile force resistant rod is fixedly attached along the tensile rod channel providing a reduced eccentricity moment between the tensile force resistant portion and the joist and extends through the rim joist and the guardrail post for the compressive connection. In one aspect of the current embodiment, the tensile force resistant rod is fixedly attached to the tensile rod channel using connectors selected from a group consisting of welding, treads to nut, and threads to welded threaded element.

In another embodiment of the invention, the connection element includes a first flat plate, where the first flat plate is the tensile force resistant portion having a tensile force resistant rod channel disposed in a proximal end at least one shear bolt through hole disposed in a distal end, a second flat plate where the second flat plate is a rim joist abutting portion, a tensile force resistant rod, where a distal end of the tensile force resistant rod is fixedly attached to the tensile force resistant rod channel and the second flat plate is disposed at a normal angle along the tensile force resistant rod and at a normal angle to the first flat plate The current embodiment further includes at least one shear bolt disposed through the shear bolt through-hole and through the joist, where the tensile force resistant portion is compressively coupled to the joist by a nut and washer threadably tightened to the shear bolt, and a proximal end of the tensile force resistant rod extends through the rim joist and through the guardrail post, where the guardrail post is compressively coupled to the rim joist by the guardrail post coupler.

In one aspect of the invention, the guardrail post coupler includes a nut and washer, where the nut fixedly attaches to threads of the tensile force resistant proximal end, and the nut fixedly compresses the washer to the post, whereby compressively joining the post to the rim joist.

In another aspect of the invention, the joist coupler includes a nut and washer, where the nut fixedly attaches to threads of a distal end of the shear resistant portion, and the nut fixedly compresses the washer to the joist, whereby compressively joining the post to the joist

In a further aspect of the invention, the joist material strengthening element can be a threaded screw or a nail, where the joist material strengthening element binds the joist material to prevent splitting of the joist material.

The invention also includes a method of using the reduced eccentricity moment guardrail post connector by providing a deck that includes at least a deck floor, a deck rim joist and a joist, wherein the rim joist is disposed perpendicularly at an end of the joist and the guardrail post is disposed perpendicularly on the rim joist and perpendicularly to the joist. The method further includes providing at least one post for attaching to the rim joist and providing a connection element, where the connection element has a tensile force resistant portion and at least one shear resistant portion, and the tensile force resistant portion is connected at about a normal angle to a the shear force resistant portion, and the shear force resistant portion is disposed through the joist and compressively couples the tensile force resistant portion adjacent to the joist providing a reduced eccentricity moment between the tensile force resistant portion and the joist. The tensile force resistant portion extends through the rim joist and the guardrail post, and compressively couples the guardrail post to the rim joist, where the tensile force resistant portion is disposed along the joist. The method also includes providing a guardrail post coupler disposed at a proximal end of the tensile force resistant portion, where the guardrail post coupler provides the compressive joining of the guardrail post to the rim joist, and providing a joist coupler disposed at a distal end of the shear resistant portion, where the joist coupler provides the compressive joining of the connector element to a joist. The method also includes providing a joist material strengthening element disposed into the joist at an angle about parallel with the guardrail post, where the tensile force resistant portion resists tensile loads when horizontal forces are imparted on the guardrail post, the shear resistant portion resist shear forces when the horizontal forces are imparted on the post, and the material strengthening element resist tensile loads in the joist.

BRIEF DESCRIPTION OF THE FIGURES

The objectives and advantages of the present invention will be understood by reading the following detailed description in conjunction with the drawing, in which:

FIG. 1 shows an exploded perspective cutaway view of the guardrail post connector according to the present invention.

FIGS. 2(a)-(b) show perspective cutaway views of the guardrail post connector according to the present invention.

FIGS. 3(a)-(d) show perspective views of different embodiments of the guardrail post connector according to the present invention.

FIGS. 4(a)-(b) show planar views of alternative configurations of the guardrail post connector according to the present invention.

FIG. 5 shows a load-deflection graph of test results for the angled bracket embodiment of FIG. 3(a) according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Although the following detailed description contains many specifics for the purposes of illustration, anyone of ordinary skill in the art will readily appreciate that many variations and alterations to the following exemplary details are within the scope of the invention. Accordingly, the following preferred embodiment of the invention is set forth without any loss of generality to, and without imposing limitations upon, the claimed invention.

A device enabling easy and correct assembly of deck railing posts to a deck base while supplying substantial support is provided. A method of fabricating the device is disclosed.

FIG. 1 shows an exploded perspective cutaway view of the guardrail post connector assembly 100 according to one embodiment of the current invention. This embodiment includes a connector rod 102 having a shear connection section 104 and a tension connection section 106, where the tension connection section 106 is disposed at approximately a normal angle to the shear connection section 104. The connector rod 102 has a shaped shear sleeve 108 disposed about the shear connection section 104. The connector rod 102 further has a threaded proximal end 110 and a threaded distal 112, where the proximal end 110 is fitted through a rim joist 114 and through a guardrail post 116 then secured thereto using a threaded nut 118 and washer 120. Additionally, the distal end 112 and shear sleeve 108 are fitted through a joist 122, where the washer 120 and threaded nut 118 are assembled to the threaded distal end 112 of the rod 102. At least one joist material strengthening element 124 is input to the joist 122 at an angle that is normal to both the shear connection section 104 and the tension connection section 106, where the joist material strengthening element 124 supplements the strength of a region of the joist 122 around the shear sleeve 108 and shear connection section 104.

The diameter and length of the connector rod in combination with the location of the joist holes 126 and the material strengthening element 124 are specifically made to guide the location of the shear connection section 104 so the connection will provide adequate strength. The strength of the post to deck framing connection will be determined by the diameter of the connector rod 102, the length of the connector rod 102 and the location of the holes 126 and the use of material strengthening elements 124 in the joist 122. The device incorporates the strength needed to meet the requirements of the building code with economy by adjusting these dimensions.

The addition of the material strengthening elements 124 enables the hole 126 to be placed closer to the top and/or bottom of the joist 122 so that greater leverage and capacity results. The current state of the art require a distance from the top and/or the bottom of the joist 122 to the hole 122 to avoid material failure and breaking.

FIGS. 2(a)-((b) show perspective cutaway views of the guardrail post connector assembly 100 according to the embodiment shown in FIG. 1. As shown in FIG. 2(a), the connection rod 102 is inserted through the shear sleeve 108 (not shown) and the post 116 is secured to the rim joist 114, and the material strengthening element 124 is shown incorporated in the top of the joist 122. As shown in FIG. 2(b), the threaded proximal end 110 of the connection rod 102 is inserted through the joist 122 and secured using the threaded nut 118 and washer 120. The distal end 112 of the connection rod 102 is inserted through the rim joist 114 and guardrail post 116 and secured using the threaded nut 118 and washer 120. The material strengthening element 124 is shown incorporated in the bottom of the joist 122. It should be apparent that the size and shape of the washer 120 provides different advantages in strength and appearance, where a large circular shape or large square shape improves connection strength of the guardrail post 116.

FIGS. 3(a)-(d) show perspective views of some embodiments of the guardrail post connector 300, with the post 116, rim joist 114, and joist 122 removed for illustrative purposes. According to FIGS. 3(a)-(c), the embodiments include a connection element or connector plate 302 having a generally planar shear connection section 304 and a generally planar tension connection section 306, where a distal end of the tension connection section 306 is disposed at approximately a normal angle to the shear connection section 304 proximal end. The connector plate 302 has at least one shear bolt 308 disposed through the tension connection section 306. The shear bolt 308 inserts through the joist (not shown) to provide shear resistance when horizontal forces are exerted on the guardrail post (not shown). The connector plate 302 further has a connector rod receiving channel 310 disposed through the wall of the tension connection section 304 and through the wall of the shear connection section 302. A connector rod 312 having a proximal end 314 and a distal end 316 is fixedly attached to the rod receiving channel 310, where the proximal end 314 is fitted to the channel and secured thereto. Further shown is at least one material strengthening element 124 disposed in the joist (not shown) perpendicular to the shear bolt 308 and perpendicular to the connector rod 312, where the number of material strengthening elements used is related to the required strengthening of the joist material.

Referring to FIG. 3(a), the connector plate 302 is shown with a threaded mounting element 318 connected to the rod receiving channel 310, by welding 320 for example, and the connection rod 312 is a threaded bolt having threads at the proximal end 314 and a bolt head at the distal end 316, with the threaded proximal end 314 inserted to the threaded mounting element 318.

Referring to FIG. 3(b), the connector plate 302 is shown with a connection rod 312 that is threaded at the distal end 316 and unthreaded at the proximal end 314, where the unthreaded proximal end is connected to the rod receiving channel 310, by welding 320 for example. The guardrail post (not shown) is secured to the rim joist (not shown) when the nut 120 and washer 118 are tightened at the distal end 316 of the connection rod 312.

Referring to FIG. 3(c), the connector plate 302 is shown with a shear connection section 304 incorporated with the connection rod 312, by welding for example, and the connection rod 312 that is threaded at the distal end 316 and unthreaded at the proximal end 314, where the unthreaded proximal end is connected to the rod receiving channel 310, by welding 320 for example. The guardrail post (not shown) is secured to the rim joist (not shown) when the nut 120 and washer 118 are tightened at the distal end 316 of the connection rod 312.

FIG. 3(d) shows the guardrail post assembly of the apparatus in FIG. 1, with the post 116, rim joist 116, and joist 122 removed for illustrative purposes. The connection rod 102 is inserted through the shear sleeve 108 and the material strengthening element 124 is incorporated in the top of the joist 122 (not shown). The shear sleeve has a rounded feature 322 for conforming to a the bending shape of the connection rod 106. Also shown, the threaded proximal end 110 of the connection rod 102 is secured using the threaded nut 118 and washer 120. The distal end 112 of the connection rod 102 is secured using the threaded nut 118 and washer 120. The material strengthening elements 124 are incorporated in the joist 122.

FIG. 4(a)-(b) show planar views of alternative configurations of the guardrail post connector according to the present invention. FIG. 4(a) shows one configuration where two of the systems 300 described in FIG. 3(a) are used to secure the guardrail post 116. The configuration shown here shows the capacity to resist applied force (F) from both the inward and outward directions. FIG. 4(b) shows another configuration where one of the systems 300 described in FIG. 3(a) is used to secure the guardrail post 116, and a-bolt assembly 404 is used as a bottom connection of the guardrail post 116. The configuration shown here shows the capacity to resist applied force (F) from the outward direction.

The inventor has performed controlled tests to verify the strength of the guardrail post connection meets structural code criteria. FIG. 5 shows a load-deflection graph 500 of test results for the angled bracket embodiment of FIG. 3(a) according to the present invention. A horizontal load was applied to the top region of the post and the post deflection was measured. The graph shows the integrity of the connection remains until approximately 530 pounds of horizontal force at almost 7-inches of deflection.

As method of fabricating the guardrail post connector, FIGS. 3(a) and 3(b) provide an exemplary methods that includes fabricating the connector plate from a sheet of steel or the like, where at least one shear bolt hole and at least one rod receiving channel are disposed through the connector plate using stamping, cutting or machining techniques. Alternately, at least one shear hole and at least one threaded mounting element receiving channel are disposed through the connector plate using stamping, cutting or machining techniques. The connector plate is bent along the rod receiving or threaded mounting element receiving channel region and transverse to the plate length, at approximately a right angle. The receiving channel is made to span from along the tension connection section to along the shear connection section such that the receiving channel follows the bend in the connector plate. The rod having a proximal end and a threaded distal end is fixedly attached to the rod receiving channel, where the proximal end is fitted to the channel and secured thereto using welding techniques or the like. A washer and threaded nut are assembled to the threaded distal end of the rod. Alternately, the threaded mounting element is fixedly attached to the mounting element receiving channel so a bolt with a washer can be assembled to the coupler nut.

The width and length of the connector plate in combination with the location of the holes are specifically made to guide the location of the shear bolts so the connection will provide adequate strength. The minimum distance of the first shear bolt from the end of the floor joist is guided by the distance from the normal angle of the connector plate to the first connector plate shear bolt hole and the minimum distance of the shear bolt to the top of the floor joist is guided by the width of the connector plate and the location of the shear bolt hole in the middle of the plate. The distance between the shear bolts is guided by the location of the holes in the connector plate. The strength of the post to deck framing connection will be determined by the width of the connector plate, the length of the connector plate, the location of the holes in the connector plate, and the material strengthening elements. The device incorporates the strength needed to meet the requirements of the building code with economy adding the material strengthening element and by adjusting these dimensions.

The present invention has now been described in accordance with several exemplary embodiments, which are intended to be illustrative in all aspects, rather than restrictive. Thus, the present invention is capable of many variations in detailed implementation, which may be derived from the description contained herein by a person of ordinary skill in the art. For example, the guardrail post connector can be used to secure one or more rim joists 114 to the joists 122 to allow attachment of the post 116 to the rim joists 114 with bolts 404 or lag screws (not shown) at locations between the joists 122. Further, the number and size of rim joists 114, guardrail post connectors 102, bolts 312, washers 120 and screws or nails can be adjusted to provide the strength to meet the requirements of the building code with economy by adjusting the number and size.

Further, dual guardrail post connectors can be used for greater capacity and larger posts by place in one on each side of the joist and bolting through the joist to connect the two guardrail post connectors with a bolt.

Additionally, strength can be increased by using large washers on the outside of the post to distribute the load force over a wider area.

All such variations are considered to be within the scope and spirit of the present invention as defined by the following claims and their legal equivalents.