U.S. patent application number 11/786545 was filed with the patent office on 2008-10-16 for t-chord open web joist with adjustable ends.
Invention is credited to Lorraine B. Gregory, Fred E. Johnson.
Application Number | 20080250747 11/786545 |
Document ID | / |
Family ID | 39852464 |
Filed Date | 2008-10-16 |
United States Patent
Application |
20080250747 |
Kind Code |
A1 |
Johnson; Fred E. ; et
al. |
October 16, 2008 |
T-chord open web joist with adjustable ends
Abstract
The disclosed device is directed towards a truss comprising an
upper T-shaped chord. A lower T-shaped chord is coupled to said
upper chord. A plurality of web members are coupled to said
T-shaped chords. An extension section is coupled to said upper
T-shaped chord and said lower T-shaped chord approximate the web.
Said extension section is configured to by adjustable by
trimming.
Inventors: |
Johnson; Fred E.; (US)
; Gregory; Lorraine B.; (US) |
Correspondence
Address: |
Fred E. Johnson & Lorraine B. Gregory
17880 Northridge Ave.
Reno
NV
89506
US
|
Family ID: |
39852464 |
Appl. No.: |
11/786545 |
Filed: |
April 12, 2007 |
Current U.S.
Class: |
52/693 |
Current CPC
Class: |
E04C 3/16 20130101 |
Class at
Publication: |
52/693 |
International
Class: |
E04C 3/02 20060101
E04C003/02 |
Claims
1. A truss comprising: An upper chord having a T-shape; A lower
chord having a T-shape coupled to said upper T-shaped chord; A web
coupled to said upper T-shaped chord and said lower T-shaped chord.
An extension section coupled to said upper T-shaped chord and said
lower T-shaped chord proximate the web comprising an adjustable end
block.
2. The truss assembly of claim 1, wherein said upper chord has a
T-shaped cross section comprised of a horizontal section and a
vertical section.
3. The truss assembly of claim 1, wherein said lower chord has a
T-shaped cross section comprised of a horizontal section and a
vertical section.
4. The truss assembly of claim 1, wherein comprising an extension
section at each end with an adjustable end block.
5. The T-shaped upper chord of claim 2, wherein said adjustable end
block is connected by a bulbous rabbet and tenon.
6. The T-shaped lower chord of claim 3, wherein said adjustable end
block is connected by a bulbous rabbet and tenon.
7. The truss adjustable end block of claim 4, wherein said
adjustable end block having a bulbous tenon matching the bulbous
rabbet of the T-shaped chords.
8. The truss assembly of claim 1, wherein said extension section is
configured to be trimmed.
9. The truss assembly of claim 1, wherein said web is connected to
an extension section by a bulbous rabbet and tenon.
10. The truss adjustable end block of claim 4, wherein said
adjustable end block has a bulbous tenon matching the bulbous
rabbet of said web.
11. A method of using a truss comprising; Providing a first
structural support configured to receive the truss and a second
structural support configured to receive the truss, the truss
comprising an upper T-shaped chord, a lower T-shaped chord, a web
coupled to said upper T-shaped chord and said lower T-shaped chord,
and a first extension section coupled to said upper T-shaped chord
and said lower T-shaped chord proximate said web and a second
extension section coupled to said upper T-shaped chord and said
lower T-shaped chord opposite first extension section; Trimming
said first extension section to couple with said first structural
support; Trimming said second extension section to couple with said
second structural support.
Description
BACKGROUND
[0001] The present disclosure relates to the field of joist and
truss construction. In particularly the disclosure relates to a
broad spectrum of joist's or trusses having T-shaped chords with
the benefits of adjustable length.
[0002] Current joist designs offer different design types and can
fall into two general categories, open web truss or closed web
joist. Both have disadvantages for the consumer.
[0003] One type of conventional open web truss which is used for
supporting building floor and roof structures and the like is
formed by two parallel wooden chords, such as 2.times.4 or
2.times.3 dimensions, or the use of composite lumber such as
Laminated Veneer Lumber (LVL), arranged one over the other
interconnected by webs of steel or wood. The webs may be attached
by gluing or by sheet metal connector plates having tamped teeth
protruding out allowing them to embed into the wooden chords. Such
a truss is generally manufactured in a factory and transported to a
construction site for installation as a component of the building.
This type of truss is known in the art of trusses as an open web
truss and has the ability to be designed with the chord being
oriented either in the flat or wide direction or vertically or the
narrow direction. While the truss with the flat lumber suffers from
not enough material for strength the vertically assembled truss
suffers from too narrow of a nailing surface.
[0004] It is also known in the art of joist design to build a solid
web joist consisting of two parallel wooden chords connected by a
continuous solid web such as plywood or Oriented Strand Board
(OSB). Such a joist suffers from having the solid web which doesn't
leave any area for utilities such as plumbing, electrical or duct
work to pass through them.
[0005] There are current designs combining both features of the
solid web joist and an open web truss. These combinations are
limited in production due to difficulty in manufacturing or to
weaknesses due to lumber orientation.
[0006] Therefore there is a need for a joist that can combine the
strength of a solid web joist with the capabilities of an open web
truss and the flexibility of an adjustable length which prior art
has not addressed.
SUMMARY
[0007] The disclosed device is directed towards a strong open web
truss formed from an upper chord and a lower chord that are
interconnected by diagonal and/or vertical webs. The chords are
T-shape providing strength in the vertical direction and giving a
wider nailing surface in the horizontal direction. An extension
portion is coupled to the upper chord and lower chord with a
self-locking bulbous rabbet proximate the web at each end allowing
the length of the truss to be adjusted. Typically the truss is
assembled from wooden components.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The embodiments of the truss of the prescribed invention are
shown in detail below with reference to attached drawings.
[0009] FIG. 1 is a partial elevation view of an exemplary
truss.
[0010] FIG. 2 illustrates a complete isometric view of an exemplary
truss.
[0011] FIG. 3 is a perspective view of a T-shaped chord.
[0012] FIG. 4 is a cross sectional end view of the T-shaped chord
and connection to the end adjustable block using a self-locking
bulbous rabbet.
[0013] FIG. 5 is an exploded cross sectional view of the
self-locking bulbous rabbet in detail.
DETAILED DESCRIPTION
[0014] Persons of ordinary skill in the art will realize that the
following disclosure is illustrative only and not in any way
limiting. Other embodiments of the invention will readily suggest
themselves to such skilled persons having the benefit of this
disclosure.
[0015] This disclosure describes a truss with T-shaped chords. The
T-shaped chord includes a horizontal section connected to a
vertical leg section approximate the center of the horizontal
section forming a T. The chords will be interconnected by webs
connected to the vertical section of the T-shaped chord. The truss
includes extension sections at opposite ends of the chords. The
extension sections extend beyond the webbing. The extension
sections are configured to be adjustable allowing for proper fit
upon installation of the truss. The extension sections generally
having an I-beam cross sectional shape. Particularities for the
adjustable sections are described below in more specific
detail.
[0016] FIG. 1 illustrates a partial elevation view of an exemplary
truss. The truss 10 comprises an upper chord 21 combining a
horizontal section 111 with a vertical section 11A and a lower
chord 21 combining a horizontal section 11 with a vertical section
11A. In an exemplary embodiment, the upper and lower horizontal
sections 11 can be made of solid lumber, such as 2.times.3 or
2.times.4 lumber or from composite lumber such as Laminated Veneer
Lumber (LVL), GluLam, Laminated Strand Lumber (LSL) other types of
composite lumber. The vertical section 11A can be made of thinner
lumber such as 1.times.3 or 1.times.4 or from the same thickness
lumber as the horizontal section 11 is made. The vertical section
may be made of solid lumber or composite lumber such as Laminated
Veneer Lumber (LVL), GluLam, or Laminated Strand Lumber (LSL) or
other types of composite lumber. The upper vertical section 11A is
coupled with a strut or web 13 to the lower vertical section 11A.
In an exemplary embodiment, the horizontal sections 11 and the
vertical sections 11A may be comprised from a single part or from
individual parts.
[0017] The web members 13 are generally arranged in a Warren or V
type truss pattern. In another exemplary embodiment, the webs 13
may be arranged in a fan type arrangement where a vertical web 14
and a diagonal web 13 intersect at the vertical chord section 11A.
The web members 13, 14 may be connected to the vertical section of
the chord 11A by metal connector plates or by finger type adhesive
joints or by some other fashion. The web members 13, 14 may be
comprised of solid lumber, composite lumber or by metal, either
stamped sheet metal or tubular. It will be appreciated by others in
the art that other materials may be used while still embodying the
spirit of the present invention.
[0018] The adjustable truss 10 is constructed with an adjustable
end block 12 at each end having a bulbous tenon 16 machined on the
top and bottom edge allowing it to lock itself into the vertical
sections 11A. In the exemplary embodiment the truss 10 will have a
similar bulbous rabbet 16 machined into the vertical sections at
the extension to accept the adjustable end block 12. The connection
between the adjustable end block will be accomplished with glue.
The adjustable end block 12 may be comprised of solid lumber or of
composite lumber. The first web 13 may comprise a Bulbous rabbet 16
on one edge to receive a bulbous tenon 17 from one edge of the
adjustable end block 12. Those skilled in the art will appreciate
that the bulbous tenon 17 and rabbet 16 is a self-locking
connection and that it requires no clamping time for gluing,
speeding up production time.
[0019] FIG. 2 illustrates a complete isometric view of the
invention in an exemplary form. In this exemplary embodiment, truss
10 includes an upper chord 21 comprised of a horizontal section 11
with a vertical section 11A and a lower chord 21 comprised of a
horizontal section 11 with a vertical section 11A. The upper chord
21 is interconnected to the lower chord 21 by way of webs 13, 14
configured in a v-shape configuration with multiple spans. An
opening 15 approximate the center of the span can be used to
facility additional space needed for placement of plumbing or duct
work. The opening 15 can be facilitated by a web 14 placed
vertically at each end of the opening 15. In another alternative
exemplary truss, the web 14 maybe placed at the beginning of the
webs 13 and the adjustable end block 12. In this alternative
embodiment the vertical web 14 may also include a bulbous rabbet 16
to receive the bulbous tenon 17. It will be appreciated by others
skilled in the art that other web configurations may be used.
[0020] FIG. 3 is an illustration of a perspective view of the
T-shaped chord. The T-shape chord 21 will be comprised of a flat
horizontal section 11 and a vertical section 11A. In an alternative
exemplary form, the T-shaped chord 21 may be comprised of a
horizontal section 11 and multiple vertical sections 11A. Those
skilled in the art will recognize that the T-shape offers strength
in two directions, horizontally and vertically without the waste of
using a larger solid piece of lumber and therefore making more
efficient use of our timber resources.
[0021] FIG. 4 is a cross sectional end view of the connection
between the chords 21 and the adjustable end block 12. In the
exemplary truss 10 the chords 21 are connected to the adjustable
end block 12 with a bulbous rabbet 16 and tenon 17 and facilitated
with an adhesive. The vertical section 11A of the chord 21 will
have a bulbous rabbet 16 at the end of the truss 10 to accept the
bulbous tenon 17 of the adjustable end block 12. An adhesive may be
applied between the bulbous rabbet 16 and the bulbous tenon 17.
[0022] FIG. 5 illustrates an exploded cross sectional View of the
connection between the adjustable end block 12 and the chord 21.
The chord 21 comprised of the horizontal section 11 and the
vertical section 11A. The vertical section 11A having a bulbous
rabbet 16 to accept the bulbous tenon 17. The bulbous tenon 17
comprised of a bulbous end 20 tapers to a narrower neck 18 and a
chamfered section 19. Likewise, the bulbous rabbet 16 comprised
identically to accept the bulbous tenon 17.
* * * * *