U.S. patent application number 13/349482 was filed with the patent office on 2012-07-26 for scaffold apparatus, method and system.
This patent application is currently assigned to Next Generation Scaffold Services Inc.. Invention is credited to Johnny Russel Curtis, Yates Wesley Hayman, Steve Howard Thacker.
Application Number | 20120186911 13/349482 |
Document ID | / |
Family ID | 46543331 |
Filed Date | 2012-07-26 |
United States Patent
Application |
20120186911 |
Kind Code |
A1 |
Thacker; Steve Howard ; et
al. |
July 26, 2012 |
SCAFFOLD APPARATUS, METHOD AND SYSTEM
Abstract
Scaffold components and system for coupling a horizontal member
to a vertical member of a scaffold, comprising a horizontal member
and a wedge head attached to each end of the horizontal member each
wedge head having an associated wedge assembly.
Inventors: |
Thacker; Steve Howard; (The
Woodlands, TX) ; Curtis; Johnny Russel; (Denham
Springs, LA) ; Hayman; Yates Wesley; (Brookhaven,
MS) |
Assignee: |
Next Generation Scaffold Services
Inc.
Las Vegas
NV
|
Family ID: |
46543331 |
Appl. No.: |
13/349482 |
Filed: |
January 12, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61461938 |
Jan 25, 2011 |
|
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|
Current U.S.
Class: |
182/186.8 ;
29/428 |
Current CPC
Class: |
Y10T 29/49815 20150115;
Y10T 29/49826 20150115; E04G 7/307 20130101; E04G 7/32
20130101 |
Class at
Publication: |
182/186.8 ;
29/428 |
International
Class: |
E04G 7/32 20060101
E04G007/32; E04G 21/14 20060101 E04G021/14 |
Claims
1. An apparatus for coupling a horizontal member to a vertical
member of a scaffold, comprising: a horizontal member and a first
wedge head coupled to a first end of the horizontal member; and a
first wedge assembly partially within the first wedge head, the
first wedge assembly pivotably coupled to the first wedge head, the
first wedge assembly further comprising a first handle communicably
coupled via a first wedge linkage assembly to a first wedge.
2. The apparatus of claim 1, further comprising the first handle of
the first wedge assembly further being springably coupled to the
first wedge head, said first handle, when actuated, operable to
cause the first wedge to fully or partially extend or retract into
the first wedge head.
3. The apparatus of claim 2, further comprising a second wedge head
coupled to a second end of the horizontal member; and a second
wedge assembly partially within the second wedge head, the second
wedge assembly pivotably coupled to the second wedge head, the
second wedge assembly further comprising a second handle
communicably coupled via a second wedge linkage assembly to a
second wedge.
4. The apparatus of claim 3, further comprising the second handle
of the second wedge assembly further being springably coupled to
the second wedge head, said second handle, when actuated, operable
to cause the second wedge to fully or partially extend or retract
into the second wedge head.
5. The apparatus of claim 4, further comprising a cam mechanism and
a first rod within the horizontal member, the first end of the
first rod rotatably coupled to the first handle via the first wedge
assembly and the second end of the first rod pivotably coupled to a
first end of the cam mechanism within the horizontal member, the
center of the cam mechanism being rotatably coupled to the
horizontal member.
6. The apparatus of claim 5, further comprising a second rod within
the horizontal member, the first end of the second rod rotatably
coupled to the second handle via the second wedge assembly and the
second end of the second rod pivotably coupled to the second end of
a cam mechanism within the horizontal member.
7. The apparatus of claim 6, the first handle operatively coupled
to the first wedge and first rod and second handle coupled to the
second wedge and second rod, the first rod being operatively
coupled to the second rod via the cam mechanism, such that when the
first handle is moved, the second handle simultaneously moves in
correspondence, such that the first wedge and the second wedge
extend or retract simultaneously.
8. The apparatus of claim 1, in combination with a rosette having a
set of radially arranged cut-outs, the rosette affixed in coaxial
alignment with a vertical member.
9. The apparatus of claim 8, wherein each wedge head has mating
elements corresponding to the radially arranged cut-outs of the
rosette, wherein, when the mating elements of the wedge head are
received in the radially arranged cut-outs of the rosette, the
wedge assembly, when actuated, causes the wedge to rigidly couple
the horizontal member to the rosette.
10. An apparatus for coupling a horizontal member to a vertical
member of a scaffold, comprising: a horizontal member and a first
wedge head coupled to a first end of the horizontal member; a first
wedge assembly partially within the first wedge head, the first
wedge assembly pivotably coupled to, and biased with reference to
the first wedge head, the first wedge assembly further comprising a
first handle and a first wedge; a second wedge head coupled to a
second end of the horizontal member; a second wedge assembly
partially within the second wedge head, the second wedge assembly
pivotably coupled to, and biased with reference to the second wedge
head, the second wedge assembly further comprising a second handle
and a second wedge; and the first handle of the first wedge
assembly or the second handle of the second wedge assembly, when
either are actuated, being operable to cause both of the first
wedge and second wedge to fully or partially extend or retract,
simultaneously.
11. The apparatus of claim 10, further comprising a cable having a
first end and a second end coupling the first handle and linkage
assembly of the first wedge head at one end of the horizontal
member to the second handle at the second wedge head via pulley at
a second end of the horizontal member.
12. The apparatus of claim 11, wherein the first wedge head serves
as a housing around portions of the first handle and the second
wedge head serves as a housing around portions of the second
handle.
13. The apparatus of claim 10, wherein the first handle is
dimensioned as a substantially horizontal handle grip extension
having a substantially vertical wedge extending in a substantially
orthogonal direction due to an incurvature from the horizontal
handle grip extension and wherein a cable linkage assembly is
located proximate the bottom of the vertical lock extension and
serves as an anchor point from the first handle to first end of the
cable.
14. The apparatus of claim 13, wherein the second handle is
dimensioned as a substantially horizontal handle grip extension
having a substantially vertical wedge extending in a substantially
orthogonal direction due to an incurvature from the horizontal
handle grip extension and wherein cable linkage assembly is located
on the bottom of the horizontal handle grip extension between the
end of the horizontal handle grip extension and the point of
curvature from the horizontal handle grip extension to the vertical
wedge and serves as an anchor point from second handle to second
end of the cable.
15. The apparatus of claim 14, wherein first handle has an aperture
located proximate the point of curvature between the horizontal
handle grip extension and the vertical wedge, said aperture
configured to axially receive a pin, rivet, screw or other similar
structure through the first handle so as to rotatably couple the
first handle through the walls of the first wedge head; and the
second handle has an aperture located proximate the point of
curvature between the horizontal handle grip extension and the
vertical wedge to axially receive a pin, rivet, screw or other
similar structure through the second handle so as to rotatably
couple the second handle through the walls of the second wedge
head.
16. The apparatus of claim 15, wherein the tension of the cable
operates to bias the wedge portions at each end of the horizontal
member simultaneously in either the extended or retracted position
depending on the position of their respective handles.
17. The apparatus of claim 10, in combination with a rosette having
a set of radially arranged cut-outs, the rosette affixed in coaxial
alignment with a vertical member.
18. The apparatus of claim 17, wherein each wedge head has mating
elements corresponding to the radially arranged cut-outs of the
rosette, wherein, when the mating elements of the wedge head are
received in the radially arranged cut-outs of the rosette, the
wedge assembly, when actuated, causes the wedge to rigidly couple
the horizontal member to the rosette.
19. A method for coupling a horizontal member to a vertical member
of a scaffold, comprising the steps of: providing a horizontal
member having a wedge head coupled to each end of the horizontal
member, the wedge heads each having therein a wedge assembly
partially within the wedge head, each wedge assembly pivotably
coupled to its respective wedge head, each wedge assembly further
comprising a handle communicably coupled via a wedge linkage
assembly to a wedge, the wedge linkage assemblies being operatively
coupled via a cam mechanism within the horizontal member; and
disengaging either handle causing each wedge to simultaneously,
partially retract into its respective wedge head.
20. The method of claim 19, further comprising the step of placing
each wedge head on a corresponding rosette of a vertical member and
engaging one of the handles so as to cause each wedge to lock the
ends of the horizontal member simultaneously to the vertical
members.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. Provisional
Application No. 61/461,938 filed on Jan. 25, 2011, entitled
"SCAFFOLD SYSTEM".
FIELD OF THE INVENTION
[0002] This invention relates to modular scaffolding systems that
are erected as impermanent structures to support platforms.
Scaffolding is used, inter alia, in the industrial, commercial,
petro-chemical, power source, general industry and residential
construction markets.
BACKGROUND
[0003] In 2008, the Bureau of Labor Statistics' Census of Fatal
Occupational Injuries (CFOI) reported 88 fatalities occurred in the
year 2007 related to the use of scaffolds and many more injuries.
Twenty-seven percent (27%) of the fatalities and many of the
injuries involved falls off of welded frame scaffolds over 25 feet
high during the installation of the scaffolds. Safety officials
recommend that scaffolding falls be pre-empted through the use of
sequential erection techniques. This involves installing guardrails
and standards at regular distances along the scaffold such that the
exposed platform edge is not greater than a bay length between
intervals. The use of safety harnesses or belts tethered to
guardrails during the erection process is also a recommended safety
practice. However, the use of safety harnesses to deter fall
injuries during scaffold erection is quite limited due to the
components used in conventional scaffolds. The nature and design of
conventional scaffold components, as described herein,
disadvantageously do not allow the effective use of safety
harnesses during the erection process.
[0004] Tube and coupler scaffolds are so-named because they are
built from tubing connected by coupling devices. Due to their
strength, they are frequently used where heavy loads need to be
carried, or where multiple platforms must reach several stories
high. Components of scaffolds include vertical standards having
coupling rings or rosettes, horizontal components such as ledgers
and guardrails coupled to the coupling rings or rosettes, footings,
decks/platforms and diagonal braces. Their versatility, which
enables them to be assembled in multiple directions in a variety of
settings, also makes them difficult to build correctly.
[0005] Conventional scaffolding systems have various components.
FIG. 1 illustrates a supported scaffold 100 consisting of one or
more platforms supported by rigid support members such as poles,
tubes, beams, brackets, posts, frames and the like. More
specifically, the supported scaffold 100 includes the following
components: deck/platform 101, horizontal members, or ledgers 102,
vertical standards 103. Additional components include diagonal
braces to increase the stiffness and rigidity of the scaffold
100.
[0006] FIG. 2 is an illustration of a vertical standard 103.
Vertical standards are typically cylindrical tubes 200 comprised of
hot-dip galvanized steel or aluminum. A collar with an expanded or
reduced diameter or a spigot at either or both ends of the vertical
standard facilitates the joining of vertical standards from end to
end. Rosettes 201 are positioned and then welded or otherwise
attached along the tubes providing connections for horizontal
members and diagonal braces. The vertical standard can have from
one to 8 or more rosettes placed along the tubing using a
predetermined spacing between rosettes, for example, about every 20
inches.
[0007] FIG. 3 illustrates a ledger 102. A ledger is a horizontal
member that serves as both a guardrail and bracing element. The
ledger 102 is comprised of tubing 300, heads 301 and wedges 302.
Ledgers 102 are available in different lengths, depending on the
scaffolding bay length, deck type and load. It is the conventional
manner in which these ledgers are coupled to vertical standards
that contribute to scaffolding falls as further described herein.
Once the tubing on a level is installed, decks or platforms 101
made of, e.g., hot-dip galvanized steel, aluminum, wood or an
aluminum frame with plywood board are installed to allow workers to
traverse the scaffold 100 and install the guardrails (e.g., ledgers
102).
[0008] Referring now to FIG. 4, wedge 302 is shown being hammered
into the slot or gap of head 301 at the end of a ledger 102 so as
to couple it to the rosette 201 of the vertical standard 200. This
must be done by a worker first at the proximate end of the ledger
102 and then at the distal end of the ledger 102. However, as the
proximate end of the ledger 102 is being coupled to the vertical
standard using the wedge 302, the distal end of the ledger 102 is
free and uncoupled, that is, until the worker can traverse the
platform to the distal end of the ledger 102 and hammer in a wedge
302 at the distal end. During this time, the distal end of the
ledger 102 remains uncoupled from the vertical standard. Hence, if
the installer is harnessed to the ledger 102 and the scaffold tilts
toward the uncoupled, distal end, the installer may tumble down the
platform and the safety harness will exit the uncoupled end of the
ledger, providing no measure of safety to the installer.
[0009] A conventional rosette 500, as seen in FIG. 5, has a central
aperture 503 to receive the vertical tubing, four small openings
501A-D to facilitate right-angled connections and four larger
openings 502 A-D to facilitate connections at certain plurality of
angles. Typically, a vertically and horizontally slotted head 504
coupled to the end of a ledger is positioned with respect to the
rosette 500 such that the horizontal slot of the head 504 is
positioned over and under the rosette 500 and the vertical slot of
the head is aligned with an aperture of the rosette 500. A wedge
302 is then hammered into the vertical slot (or gap) to couple the
ledger 102 via the head 504 to the vertical standard 103 via the
rosette 500 using, inter alia, frictional force. Note that,
disadvantageously, until the wedge 302 is installed, there is
significant play between the rosette 500 and head of a horizontal
member giving rise to safety concerns. Furthermore, once installed,
wedges often work free when workers traverse the platform. When
these wedges work free, the scaffold can become unstable and
collapse. Further, even if the scaffold does not collapse, steel
wedges, which, as seen in the Figure, are not integrated into the
head or the ledger, can fall from the scaffold injuring workers
below.
[0010] What is desired is a scaffolding apparatus that is
configured to couple each end of a ledger (also referred to herein
as a horizontal member) to a vertical standard (also referred to
herein as a vertical member) simultaneously, and which has an wedge
assembly mechanism that allows a single installer to insert and
lock wedges at both ends of the horizontal member substantially
simultaneously to the vertical standard. The invention provides
such an apparatus.
SUMMARY
[0011] The invention comprises a scaffold apparatus that overcomes
the safety, rigidity, and labor issues inherent in conventional
scaffold systems. The ring, collar, rosette or component with
similar functionality, is referred to as a rosette with respect to
the invention; the vertical standard or component with similar
functionality, is referred to as a vertical member with respect to
the invention and the ledger, guardrail or component with similar
functionality is referred to as a horizontal member. The use of the
foregoing terms is not to be interpreted as limiting the scope of
the invention.
[0012] As noted herein, components of the invention include at
least one horizontal member and a wedge head attached to each end
of the horizontal member. A wedge assembly is located partially
within the horizontal member and each wedge head, each wedge
assembly having a handle coupled to a wedge portion for coupling
the wedge head to a vertical member.
[0013] A rosette having a set of radially arranged cut-outs, the
vertical member affixed in coaxial alignment with the rosette, is
provided to receive the wedge head having mating elements
corresponding to the radially arranged cut-outs of the rosette,
wherein, when the mating elements of the wedge head are received in
the radially arranged cut-outs of the rosette, the wedge assembly,
when actuated, causes the wedge portion to rigidly couple the
horizontal member to the rosette. The handle of the wedge assembly
is springably coupled to the wedge head, said handle, when
actuated, being operable to cause the wedge portion to partially
extend or retract into the wedge head. A rod or cable within the
horizontal member, couples the first handle of the wedge assembly
to the second handle at the other end of the horizontal member,
causing it to simultaneously engage or disengage the wedge at the
other end of the horizontal member.
[0014] Each of the wedge heads have at least one or a plurality of
mating elements or prongs dimensioned to fit within a grid of
apertures formed in the rosette, the wedge head having an opening
or slot through which the wedge portion wholly or partially extends
to lock the wedge head, and hence, the horizontal member to the
rosette and wholly or partially retracts to unlock the wedge head,
and hence, the horizontal member from the rosette.
[0015] To those skilled in the art to which this invention relates,
many changes in construction and widely differing embodiments and
applications of the invention will suggest themselves without
departing from the scope of the invention as defined herein and in
the appended claims. The disclosures and the descriptions herein
are purely illustrative and are not intended to be in any sense
limiting.
DESCRIPTION OF THE DRAWINGS
[0016] A more complete understanding of the invention may be
obtained by reference to the following Detailed Description, when
taken in conjunction with the accompanying Drawings, wherein:
[0017] FIG. 1 illustrates a scaffold structure;
[0018] FIG. 2 illustrates a vertical standard;
[0019] FIG. 3 illustrates a conventional ledger with unsecured
wedges;
[0020] FIG. 4 illustrates the installation of an unsecured wedge
into a conventional ledger head;
[0021] FIG. 5 illustrates a rosette and conventional head and
wedge;
[0022] FIG. 6 is a rosette used with an embodiment of the
invention;
[0023] FIG. 7 is an embodiment of a vertical member of the
invention;
[0024] FIG. 8 is a side view of a first embodiment of the wedge
head of the invention;
[0025] FIG. 9A is a first perspective view of a first embodiment of
the wedge head of the invention;
[0026] FIG. 9B is a second perspective view of a first embodiment
of the wedge head of the invention;
[0027] FIG. 10 is a cam mechanism used in the first embodiment;
[0028] FIG. 11 is a cutaway side view of a second embodiment being
a horizontal member in the unlocked position; and
[0029] FIG. 12 is a cutaway side view of a second embodiment being
a horizontal member in the locked position.
DETAILED DESCRIPTION
[0030] The invention comprises a scaffold system, and components
thereof, that overcomes the safety, rigidity, and labor issues
inherent in conventional scaffold systems. The ring, collar,
rosette or component with similar functionality, is referred to as
a rosette with respect to the invention; the vertical standard or
component with similar functionality, is referred to as a vertical
member with respect to the invention and the ledger, guardrail or
component with similar functionality is referred to as a horizontal
member. The use of the foregoing terms is not to be interpreted as
limiting the scope of the invention.
[0031] As noted herein, components of the invention include at
least one horizontal member which horizontal member preferably has
a wedge head at each end thereof, alone or in combination with at
least one vertical member including at least one rosette affixed in
coaxial alignment thereon, the rosette having apertures for
receiving mating elements or prongs of an wedge head (which may be
a separate component of the horizontal member, or an integrated
portion at the end of the horizontal member), a wedge assembly
within the wedge head and horizontal member, the wedge assembly
having a separate handle and wedge portion or integrated handle and
wedge portion, the wedge assembly at an end of the horizontal
member being responsively coupled to a wedge assembly at the other
end of a horizontal member using a rod or cable or other
transmission means. Each wedge head may further include one or a
plurality of prongs dimensioned to fit within a grid of apertures
formed in the rosette. The wedge head has an opening or slot
through which the wedge portion extends wholly or partially out of
the wedge head to lock the wedge head when activated by a handle,
operable to couple the horizontal member to the rosette
[0032] An aspect of the invention is a joint for use in coupling a
horizontal member to a vertical member having a rosette with a set
of radially arranged cut-outs, a horizontal member further
comprising a hollow tube having contained therein a wedge assembly,
the wedge assembly having a wedge portion at the end thereof which
is wholly or partially extendable and retractable into a hollow
tube or cavity of a wedge head and/or horizontal member. The wedge
head, located at the end of the horizontal member, has mating
elements corresponding to the radially arranged cut-outs of the
rosette. When the mating elements of the wedge head or the
horizontal member are received in the radially arranged cut-outs of
the rosette and the wedge assembly is actuated using, e.g., a
handle, causes the wedge portion to firmly join or couple the wedge
head or horizontal member to the rosette.
[0033] Referring now to FIG. 6, the top view of one embodiment of a
rosette 600 of the invention is shown. An embodiment of rosette 600
is circular in shape and has a breadth or extent. Such breadth or
extent may be any measure appropriate to allow the wedge head to
engage the rosette 600 as more fully described herein. Rosette 600
has a central aperture 601 or cut-out in a substantially circular
shape dimensioned to receive the vertical tubing of the vertical
member. In another aspect, such central aperture or cut-out may be
any shape that corresponds to the cross-sectional shape of a
vertical member. Once placed on the vertical tubing, rosette 600
can thus be welded or otherwise attached in a co-axial alignment
with the vertical tubing of the vertical member. A plurality of
rosettes can thus be positioned and affixed along the length of the
vertical tubing. Between the outer circumference of rosette 600 and
the outer circumference of the central aperture 601 are a plurality
of radially arranged cut-outs 602 for receiving prongs of at least
one wedge head as further described herein. The grid arrangement of
the radially arranged cut-outs 602 allow for multiple arrangements
of horizontal members to the vertical member via rosette 600. As
seen in FIG. 6, eight (8) radially arranged cut-outs are shown,
although a different number of radially arranged cut-outs can be
arranged on rosette 600. In an embodiment of the invention, the
radially arranged cut-outs 602 generally comprise trapezoids with
inner and outer edges having circular arcs of concentric circles of
different radii. The intersections of the line segments and arcs
can be filleted, comprising a concave easing of the interior
corners to reduce stress concentration. On a portion of, and
further cut out from, the inner and outer edges of such trapezoids
are arc shaped notches comprising a portion of a circle centered on
the trapezoid. The edges of intersection of each of the upper and
lower surfaces of the rosette with the vertical, interior walls of
the rosette can be rounded, beveled or chamfered. The radially
arranged cut-outs 602 are dimensioned to receive vertical prongs of
the wedge head. Stated otherwise, the vertical member includes at
least one rosette having a set of radially arranged cut-outs, the
vertical member affixed in coaxial alignment with the rosette, the
cut-outs to receive the wedge head having mating elements
corresponding to the radially arranged cut-outs of the rosette,
wherein, when the mating elements of the wedge head are received in
the radially arranged cut-outs of the rosette, the wedge assembly,
when actuated, causes the wedge portion to rigidly couple the
horizontal member to the rosette.
[0034] FIG. 7 is one embodiment of a vertical member 700 of the
invention having a plurality of rosettes 600 positioned and affixed
in coaxial alignment on vertical tubing 701.
[0035] FIG. 8 is a side view 800 of a first embodiment of the wedge
head of the invention wherein the handle and wedge assembly on at
least one end of horizontal member 810 are integrated into the
wedge head. Such wedge head is shown coupled to rosette 801. Wedge
head 802 includes an optional finger bar (not seen) which is
attached to, and extends from, a top side of wedge head 802 to a
position on outer surface of horizontal member 810. The finger bar
strengthens the attachment of wedge head 801 to horizontal member
810 and also protects handle 812 from damage. Rotatably integrated
into wedge head 802 is a wedge assembly which includes wedge 818
which is biased by spring 803 wound around pin 804, handle 812 and
a handle linkage assembly 806 which is rotatably coupled to wedge
head 802 with pin 808 which is seated in openings in the
apositioned inside walls of wedge head 802. Spring 803 includes a
transverse portion on the end in contact with a top surface of
wedge 818 so as to both guide wedge 818 and apply downward pressure
on wedge 818, which downward pressure is translated from pressure
on wedge 818 to rosette 801. Support 814 which is integrated into
wedge head 802 provides an upward force against the bottom surface
of wedge 818 which counteracts the downward force of spring 803 on
the top surface of wedge 818.
[0036] A first extension on which pressure is applied by a user to
lock or unlock the invention to a rosette is handle 812. An
integrated offset angled extension from handle 812 is the handle
linkage assembly 806. The handle linkage assembly 806 has a
plurality of apertures for coupling to components such as the wedge
and rod and to wedge head 802. Handle 812 and handle linkage
assembly 806 are rotatably coupled to wedge head 802 with pin 805
and are movable along an arc of motion via guide 813 and pin 807.
The first end of rod 809 is rotatably coupled to handle linkage
assembly 806 with pin 811. The second end (not seen) of rod 809 is
coupled to a second wedge at the distal end of horizontal member
810.
[0037] In a second embodiment as more fully described below, rod
809 and its related mechanisms are replaced with a cable which
couples a first handle linkage assembly in a wedge head at one end
of a horizontal member to a wedge head at a second end of the
horizontal member. The tension of the cable operates to bias the
wedges at each end of the horizontal member simultaneously in
either the extended (locked) or retracted (unlocked) position
depending on the position of their respective handles. As noted
below, the cable can be threaded around internal pins, wheels and
axles and biased with, inter alia, springs.
[0038] In operation, the wedge head 802 is at one end of the
horizontal member 810. The wedge head 802 has handle 812 pivotably
coupled to the wedge head 802 with the end of the handle 812
internal to the wedge head 802 being integrated at a first end to
the handle linkage assembly 806. The handle linkage assembly 806 is
pivotably coupled to the wedge head 802, a distal end of a wedge
818 being rotatably coupled with a pin 808 or similar mechanism to
the handle linkage assembly 806 at a mid-section thereof. The wedge
818 is biased by a transverse portion of spring 803 causing the
wedge 818 to press down against the face of a rosette when the
wedge 818 is extended by the handle 802. The first end of a rod 809
is coupled via a pin 811 or similar mechanism at a second end of
the handle linkage assembly 806 and the second end (not shown) of
the rod is coupled to a second wedge (not shown) for extension and
retraction at the distal end of the horizontal member. The coupling
of the rod 809 and wedge 818 to the handle linkage assembly at the
distal end of the horizontal member are coupled via a rotatable cam
mechanism as seen in FIG. 10 located within the hollow cylindrical
horizontal member such that the movement of rod 809 to one of
either the left or right (via motion of handle 812 at either end)
causes the wedges on both ends of the horizontal member to either
simultaneously extend (for locking when placed on a rosette) or
retract.
[0039] FIG. 9A is a first perspective view of a first embodiment of
the wedge head 802 of the invention (without the rosette) showing
handle 812 in the up position which causes the wedge 818 to be into
the extended position, thus operable to lock a horizontal member
into a locked position when first placed on a rosette.
[0040] FIG. 9B is a second perspective view of a first embodiment
of the wedge head 802 of the invention (without the rosette)
showing handle 812 in the down position which causes the wedge 818
to be into the retracted, unlocked position.
[0041] FIG. 10 is a portion of a horizontal member showing a cam
mechanism 1001 pivotably coupled at the center of a cam to the
horizontal member, the ends of the cam pivotably coupled to each of
the distal ends of rod 809, operable to cause both rods 809 to be
simultaneously movable into an extended or retracted position.
[0042] FIG. 11 is a side view of a second embodiment 1100 of the
invention. As seen therein, a cable 1101 having a first end 1101A
and a second end 1101B, couples a first handle 1103 and linkage
assembly in a first wedge head 1105 at one end of a horizontal
member 1107 to a second handle 1104 at the second wedge head 1106
via pulley 1102 at a second end of the horizontal member 1101. The
first wedge head 1105 serves as a housing around portions of the
first handle 1103 and second wedge head 1106 serves as a housing
around portions of the second handle 1104.
[0043] More specifically, first handle 1103 is dimensioned as a
substantially horizontal handle grip extension 1103A having a
substantially vertical wedge 1103B extending in a substantially
orthogonal direction due to an incurvature from the horizontal
handle grip extension 1103A. Cable linkage assembly 1103C is
located proximate the bottom of the vertical lock extension 1103B
and serves as an anchor point from first handle 1103 to first end
1101B of cable 1101.
[0044] Second handle 1104 is dimensioned as a substantially
horizontal handle grip extension 1104A having a substantially
vertical wedge 1104B extending in a substantially orthogonal
direction due to an incurvature from the horizontal handle grip
extension 1104A. Cable linkage assembly 1104C is located on the
bottom of the horizontal handle grip extension 1104A between the
end of the horizontal handle grip extension 1104A and the point of
curvature from the horizontal handle grip extension 1104A to
vertical wedge 1104B and serves as an anchor point from second
handle 1104 to second end 1101A of cable 1101.
[0045] First handle 1103 has an aperture 1103D located proximate
the point of curvature between the horizontal handle grip extension
1103A and the vertical wedge 1103B, said aperture 1103D to axially
receive a pin, rivet, screw or other similar structure through the
first handle 1103 so as to rotatably couple the first handle 1103
through the walls of the first wedge head 1105. The coupler, can
include, but is not limited to a bolt and a nut, rivet, revolute,
pin and associated washers, bushings and/or bearings, each coupler
being part of linkage assembly.
[0046] Second handle 1104 has an aperture 1104D located proximate
the point of curvature between the horizontal handle grip extension
1104A and the vertical wedge 1104B to axially receive a pin, rivet,
screw or other similar structure through the second handle 1104 so
as to rotatably couple the second handle 1104 through the walls of
the second wedge head 1106. The coupler, can include, but is not
limited to a bolt and a nut, rivet, revolute, pin and associated
washers, bushings and/or bearings, each coupler being part of
linkage assembly.
[0047] The tension of the cable 1101 operates to bias the wedge
portions 1103B, 1104B at each end of the horizontal member
simultaneously in either the locked or unlocked position depending
on the position of their respective handles. The cable can be
threaded around internal pins, wheels and axles and biased with
springs. By actuating either of handle 1103 or 1104, wedge portions
1103B, 1104B (respectively), can be simultaneously retracted or
extended into the housing portions of wedge heads 1105, 1106,
respectively. Upward facing teeth 1103E, 1104E, are integrated into
the bottom of wedge heads 1105, 1106 to receive rosette apertures
when the wedge portions 1103B, 1104B are in the unlocked positions,
that being when the first handle 1103 and second handle 1104 are in
the upper position. After the rosettes are positioned within the
teeth 1103E, 1104E (of which there may be a plurality integrated on
the wedge heads 1105, 1006), force can be applied to either the
first handle 1103 or second handle 1104, which will cause both
associated wedge portions 1103B, 1104B, respectively, to move into
the locked position. This simultaneous locking effect is
accomplished by the action of the cable 1101 working in concert
with the applied force of springs 1110, 1111.
[0048] First handle 1103 and second handle 1104, and associated
wedge portions 1103B, 1104B are each springably biased into certain
positions (extended (locked) or retracted (unlocked)) via springs
1110, 1111 which are coupled via pins, axles or similar structure,
to wedge heads 1105, 1106.
[0049] Referring to FIG. 11, which shows the unlocked position of
the wedges, when first handle 1103 is in the up position, the
second end 1101B of cable 1101 is in the rightmost position and
higher compression is applied against spring 1110. At the same
time, second handle 1104 is in the up position, first end 1101A of
cable 1101 is in the higher position and higher compression is
being applied against spring 1111.
[0050] Referring to FIG. 12, which shows the locked position of the
wedges, when first handle 1103 is in the down position, the second
end 1101B of cable 1101 is in the leftmost position and less
compression is applied against spring 1110. At the same time,
second handle 1104 is in the down position, first end 1101A of
cable 1101 is in the lower position and less compression is being
applied against spring 1111. As can be seen, by actuating one
handle to either lock or unlock its associated wedge portion, it
cause the other handle to move and either lock or unlock its
associated wedge portion simultaneously.
[0051] The embodiments further include being in combination with at
least one rosette attached, e.g., welded, to each vertical member.
Each vertical member may have a plurality of evenly or unevenly
spaced rosettes affixed, e.g., by weld, along a vertical member.
The rosette has a pattern or grid of apertures designed to receive
the mating elements, such as prongs at the end of a horizontal
member. A wedge head may be located at the end of the horizontal
member. The horizontal member is a hollow tube, preferably
cylindrical in shape, having a first end and a second end. At the
first end and the second end may be fixedly attached, a wedge head,
as more fully described herein.
[0052] The invention further includes the method for coupling a
horizontal member to a vertical member of a scaffold, comprising
providing a horizontal member having a wedge head coupled to each
end of the horizontal member, the wedge heads each having therein a
wedge assembly partially within the wedge head, each wedge assembly
pivotably coupled to its respective wedge head, each wedge assembly
further comprising a handle communicably coupled via a wedge
linkage assembly to a wedge, the wedge linkage assemblies being
operatively coupled via a cam mechanism within the horizontal
member; and disengaging either handle causing each wedge to
simultaneously, partially retract into its respective wedge head.
The method further includes the step of placing each wedge head on
a corresponding rosette of a vertical member and engaging one of
the handles so as to cause each wedge to lock the ends of the
horizontal member simultaneously to the vertical members.
[0053] In an embodiment of the invention, the design of the wedge
head at each end of each horizontal member keeps scaffold
components square and ridged at all times utilizing predetermined
angles via the grid design. The scaffold design of the invention
reduces leading edge fall hazards associated with conventional
scaffold systems. The scaffold design of the invention also reduces
the need for hand tools during the installation and dismantling of
horizontal members. Advantageously, the scaffold design of the
invention reduces the amount of labor and time needed to install
and dismantle a scaffold system.
[0054] The components of the invention can be fabricated from a
variety of materials, including galvanized or powder coated steel,
iron or other resilient material. The rosette preferably has a
seven inch (7'') diameter, and the internal first and second rods
can comprise two square, or cylindrical rods, made of e.g., steel
or iron, each having a wedge shaped wedge portion added or
integrated at an end, the opposite ends being coupled to the
crank/cam assembly. Using the grid pattern of apertures on the
rosette and head having prongs dimensioned to fit therein, various
angles between the horizontal members can be obtained (e.g., 45,
90, 180 degrees) for the elevated working platform.
[0055] Advantageously, the invention allows the erector to engage
and disengage both wedge portions of a single horizontal member
from a single point reducing installation time and creating a safer
work environment. This is because the only one of the handles
between the first end and the second end of the horizontal member
need be actuated to engage and disengage each wedge substantially
simultaneously. In this manner, up to eight (8) horizontal members
can be attached to a single vertical member by a single installer
without changing his position.
[0056] The invention further comprises a grid of components that
mesh together creating rigid angled connection among a plurality of
horizontal members at a vertical member. Both of the wedges which
are part of a wedge assembly, are locked into position at the
rosette on a vertical member from a single position. The internal
wedge portions are locked into place by an external handle
eliminating the use of any hand tools. The external handle can also
be locked into place creating a secondary locking device.
[0057] The embodiments shown and described above are only
exemplary. Even though numerous characteristics and advantages of
embodiments of the invention have been set forth in the foregoing
description together with details of the invention, the disclosure
is illustrative only and changes may be made within the principles
of the invention to the full extent indicated by the broad general
meaning of the terms used herein. For example, the concepts
described herein for coupling horizontal members to vertical
members can be used to couple bracing members to vertical members
or to horizontal members. Coupling includes, but is not limited to
attaching, engaging, mounting, clamping, welding, bolting and
components used for coupling include bolts and nuts, rivets,
clevis, latches, clamps, welds, screws, rivets and the like.
Further, a rosette having eight (8) radially arranged cut-outs is
described herein for illustrative purposes and a rosette having
more or less radially arranged cut-outs is considered to be within
the scope of this invention. Also, the invention describes a
rosette having a standard diameter of about seven (7) inches,
however, any suitable diameter can be used. The use of a wedge head
with a pair, or a wedge head with two pair, of vertical prongs is
described herein for illustrative purposes and a wedge head having
one or more prongs is considered within the scope of this
invention. The rosette can include any suitable cut-out shape that
is dimensioned to receive a corresponding prong or set of prongs of
a wedge head. The vertical member can have any number of coaxially
aligned rosettes attached thereto, the vertical spacing of such
rosettes being any such distance as is suitable for the intended
use. More generally, the invention is a scaffold system with a
horizontal member, a vertical member with at least one rosette
affixed in coaxial alignment to the vertical member and a wedge
assembly within the horizontal member, portions of the wedge
assembly for locking the horizontal member to the rosette. The
vertical member has a plurality of evenly spaced rosettes affixed
in coaxial alignment along the vertical member and at least one
rosette has a pattern or grid of apertures designed to receive the
end of the horizontal member.
* * * * *