Information
-
Patent Grant
-
6749041
-
Patent Number
6,749,041
-
Date Filed
Monday, December 23, 200222 years ago
-
Date Issued
Tuesday, June 15, 200420 years ago
-
Inventors
-
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 182 45
- 182 169
- 182 165
- 182 170
- 182 168
- 182 107
- 182 214
- 182 171
-
International Classifications
-
Abstract
A joist scaffold unit including first and second vertical legs of adjustable length disposed generally parallel to one another. Horizontal crossbars of adjustable length extend between the first and second legs. A foot is pivotally attached to the bottom end of each leg and configured to be secured to a ceiling or floor joist. A vertical brace extends from the leg or the crossbar at an angle to the ceiling or floor joist. A foot at the end thereof is configured to be secured to the ceiling or floor joist. A supporting structure is placed over spaced-apart of joist scaffold units to allow construction workers to work on a roof or the like.
Description
BACKGROUND OF THE INVENTION
The present invention generally relates to scaffolding used in building construction and the like. More particularly, the present invention resides in a scaffold unit which is attachable to joists of a floor or ceiling to facilitate repairs and construction of a roof or ceiling.
The use of scaffolding in the construction industry is well known. For example, scaffolding may be constructed on an exterior of a building to facilitate plaster or paint work. Traditionally, scaffolding has been constructed of frame members which are assembled and placed a set distance apart from one another on a flat surface, such as the ground or a floor. Planks are laid across the assemblies in order to allow construction workers and the like to be elevated to the working area.
However, such scaffolding has certain disadvantages. For example, the end metal units are typically non-adjustable in height. Adjustability is provided by stacking scaffolding units upon one another, or selecting a scaffolding which meets the requirements of the user. Also, when constructing a roof, it is common to have ceiling or floor joists underlying the ceiling during the framing and construction process. This presents a challenge for traditional scaffolding.
Accordingly, there is a continuing need for a scaffolding structure which is particularly suited for the construction and repair of roofs and ceilings when floor or ceiling joists are positioned below the intended work area. Such a scaffolding structure should preferably be adjustable in width and height so as to accommodate the needs of the construction worker. The present invention fulfills these needs and provides other related advantages.
SUMMARY OF THE INVENTION
The present invention resides in a joist scaffold unit which is particularly designed for use on floor or ceiling joists, which typically comprise wood beams running parallel to one another to create the supporting structure for the floor or ceiling. The joist scaffold unit generally comprises first and second vertical legs of adjustable length disposed generally parallel to one another. Horizontal crossbars of adjustable length extend between the first and second legs. A foot is pivotally attached to a bottom of each leg, so as to be secured to the floor or ceiling joist. The foot includes a generally U-shaped bracket configured to receive an edge portion of a joist therein.
Each leg comprises a main body having a first end telescopically and slidably received within an upper riser. A second, lower end of the main body is telescopically and slidably received within a lower riser. Thus, the legs can be adjusted in height. The main body and upper and lower risers have alignable adjustment apertures for receipt of a locking pin or the like to fix the legs at the desired height. Each crossbar is comprised of a tubular first segment which telescopically and slidably receives a second segment extending from the opposite leg. The first and second segments include alignable adjustment apertures for receipt of a locking pin therethrough to fix the width of the legs so that the feet can be properly positioned over the floor joists.
A brace of adjustable length extends from the leg or the crossbar of the scaffold at an angle towards the floor joist. A foot which is pivotally attached at an opposite end of the brace is configured to be secured to the ceiling or floor joist. Such foot includes a generally U-shaped bracket configured to receive an exposed portion of the joist, and preferably includes a fastener extendable through the foot and into contact with joist to securely connect the foot thereto. The brace is preferably comprised of a first tube that telescopically and slidably receives a second tube so as to be adjustable in length. The first and second tubes include a linable adjustment apertures for receipt of a locking pin therethrough to lock the brace at the desired length.
In use, one joist scaffold unit is secured to floor or ceiling joists, and a second is secured to floor or ceiling joists and spaced from the first joist scaffold unit. Planks or the like are then placed over the upper most crossbars to provide a supporting surface for the construction workers to be elevated with respect to the floor ceiling joists and work on the roof above.
Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings illustrate the invention. In such drawings:
FIG. 1
is a partially exploded perspective view of a scaffolding unit embodying the present invention;
FIG. 2
is a cross-sectional view taken generally along line A—A of
FIG. 1
, illustrating the adjustable nature of legs of the scaffolding unit; and
FIG. 3
is a top plan view of the leg and crossbar unit of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As shown in the accompanying drawings for purpose of illustration, the present invention resides in a scaffolding unit, generally referred to by the reference number
10
, which is particularly adapted for use in constructing or repairing roof structures when floor or ceiling joists lie below.
With reference now to
FIGS. 1-3
, the scaffolding unit
10
is comprised of first and second legs
12
and
14
having crossbars
16
extending therebetween. The vertical legs
12
and
14
are adjustable in length. In the illustrated particularly preferred embodiment, each leg
12
or
14
comprises a main body
18
having a first and telescopically and slidably received within an upper first riser
20
. A lower end of the main body
18
is also slidably connected to a lower riser
22
. This enables the legs
12
and
14
to be adjusted to a desired height. The various segments of the legs
12
and
14
include apertures
24
therethrough which are alignable within one another to receive a locking pin
26
such as a cotter pin or the like. In this manner, the height of the legs
12
and
14
can be fixed in place.
The crossbars
16
are also adjustable in length, or width, so as to alter and provide adjustment to the width of the structure
10
. With reference to
FIGS. 1 and 3
, each crossbar
16
is comprised of a tubular first segment
28
extending from one of the crossbars
12
or
14
, and a smaller second segment
30
extending from the opposite leg
12
or
14
. The second segment is telescopically and slidably received within the first segment
28
to provide width adjustment. The first and second segments
28
and
30
include alignable apertures
32
which receive a locking pin or the like to fix the relationship of the first and second segments
28
and
30
at the desired width.
To provide stability and strength, preferably, multiple crossbars
16
extend between the first and second legs
12
and
14
, although as few as a single upper crossbar
16
may be utilized in accordance with the present invention. As shown in
FIGS. 1 and 2
, notches or slits
34
are formed in the upper riser
20
so that the upper riser
20
is lowered onto the main body
18
in a crossbar
16
extending between the main bodies
18
of the first and second legs
12
and
14
will be received within the slot
34
. Similar slots
34
can be formed on either the main body
18
or lower riser
22
for the same purposes.
A foot
36
is pivotally attached to the bottom end of each leg
12
and
14
. The foot
36
is a generally U-shaped member which is sized and configured such so as to be slipped over an exposed edge of the floor or ceiling joist. Such floor and ceiling joists are one to two inches in thickness, thus the foot
36
is sized so as to fit over such edge of the joist. The feet
36
are pivotally attached to the legs
12
and
14
so that a construction worker is not limited to positioning the scaffold unit
10
running parallel to the ceiling or floor joist, but rather can elect to set up the joist scaffold perpendicular to the joist. In use, two joist scaffold units
10
are set up so that they are spaced from one another. A plank, or the like, is placed on the upper crossbars
16
of each to provide a working and supportive surface for the construction workers.
It has been found that although the feet
36
prevent lateral movements of the joist scaffold units
10
, forward or backward motion is still a possibility. Thus, the invention incorporates a vertical brace
38
which extends from either the legs
12
and
14
or crossbar
16
downwardly to a lower joist. The brace
38
includes an attachment means, such as the illustrated eyehook
40
which is received onto the legs
12
and
14
or braces
16
. In a particularly preferred embodiment, the eyehook
40
is sufficiently large so as to be received on the crossbars
16
or ends of the upper riser
20
and extend diagonally therefrom to the joists. A joist foot
42
is pivotally attached to the brace
38
at an opposite end thereof. The joist foot
42
is also a generally a U-shaped member sized so as to be positioned over an exposed edge of a joist. The joist foot
42
includes an aperture
44
for receipt of a thumb screw or other fastener which can be inserted through the joist foot
42
and into contact with the joist so as to fix the joist foot in place.
In a particularly preferred embodiment the brace
38
is adjustable in length. The brace
38
is comprised of a first tube
46
which is hollow so as to slidably and telescopically receive a second tube or rod
48
. Each tube
46
and
48
includes apertures
50
which are alignable with one another so as to receive a locking pin therethrough for fixing the length of the brace
38
. Typically in use, a brace
38
will extend from each leg
12
or
14
, or two braces
38
will extend from the crossbars
16
to provide a stable support for the construction worker.
A method of constructing the joist scaffolding unit
10
as described will now be provided. First, the main body
18
must be built. A 1″×3″ square tubing having a length of 24″ is provided. A 1″×1″ square tubing having a length of 23″ is welded thereto to form the first cross-bar segment
28
. On the opposite main body
18
, a ⅞″×⅞″ square tubing having the length of 23 inches is welded thereto so as to be aligned with the first segment
28
. This square tubing comprises the second segment
30
which is slidably received in the first segment
28
. Holes, ½″, are drilled through the crossbars
16
so as to accept a {fraction (7/16)}″ pin. The lower riser is comprised of ⅞″×2⅞″ square tubing having the length of approximately 28 inches. The crossbars
16
are formed generally in the same manner. The lower riser
22
can thus slide into the main body
18
. Holes, ⅝″, are drilled into the main body
18
and lower riser
22
to provide adjustment apertures. Thus, the lower riser
22
and main body
18
can be adjustably positioned from as little as 2′ in height to as much as 4′ in height. Slots
34
are created in the main body
18
as necessary to accommodate the lower riser
22
crossbar
16
.
The top riser is comprised of 1⅛″×3⅛″ square tubing having the length of approximately 32″. The crossbar
16
is assembled in the same manner as the others, and preferably the top crossbar
16
is welded at approximately 4″ below the top and bottom of the upper risers
20
. This enables the supporting plank to have side stability when placed over the units
10
. Notches or slots
34
are formed in the upper riser
20
so as to receive the crossbars
16
extending between the main body
18
. Similar adjustment holes
24
are formed in the upper riser
20
so as to receive a pin
26
or the like through aligned apertures
24
of the various segments of the legs
12
and
14
. The addition of the upper riser
20
enables the legs
12
and
14
to be raised approximately two more feet.
The feet
36
are then attached to the lower ends of the lower risers
22
. The U-shaped feet are approximately 1½″ in width. A hole is drilled therethrough and a pin or rivet type pin or bearing is used to connect to joist feet
36
to the lower riser
22
in a swivel-fashion.
Finally, the vertical brace
38
is created for stability. A 1¼″ diameter round tube is provided which accepts a 1″ iron rod or tube therethrough. Each segment is approximately 4′ long. The ends of the tubes are capped, if necessary, and the eyehook
40
is attached at an upper end thereof. Preferably, the eye of the hook
40
must be large enough to slip over the crossbars
16
. Holes of approximately ½″ in diameter are drilled into the tubes
46
and
48
. A joist foot
42
is attached to the lower end of the brace
38
, as described above. An aperture
44
is drilled through the joist foot for receipt of a hand-tum bolt such as a wing nut or the like which is able to grip the wood joist. Typically, a piece of iron or metal is fitted around the crossbar
16
on the inside of each vertical brace
38
to insure that the vertical brace
38
does not slip from the its place. These are preferably removably attached for adjusting purposes.
Although an embodiment has been described in detail for purposes of illustration, various modifications may be made without departing from the scope and spirit of the invention.
Claims
- 1. A joist scaffold unit, comprising:first and second vertical legs of adjustable length disposed generally parallel to one another; horizontal crossbars of adjustable length extending between the first and second legs; a foot pivotally attached to a bottom end of each leg, and configured to be secured to a ceiling or floor joist; and a brace of adjustable length extending from the lea or the crossbar at a first end thereof, and having a foot pivotally attached at an opposite end thereof configured to be secured to a ceiling or floor joist; wherein the leg and brace feet each include a generally U-shaped bracket configured to receive a portion of a joist therein.
- 2. The scaffold unit of claim 1, including a fastener extendible through the foot and into contact with the joist to securely connect the foot thereto.
- 3. A joist scaffold unit, comprising:first and second vertical legs of adjustable length disposed generally parallel to one another; horizontal crossbars of adjustable length extending between the first and second legs; a foot pivotally attached to a bottom end of each leg, and including a generally U-shaped bracket configured to receive a portion of a joist therein; a fastener extendible through the foot and into contact with the joist to securely connect the foot thereto; a brace of adjustable length extending from the leg or the crossbar at a first end thereof; a foot pivotally attached at a second end of the brace and including a generally U-shaped bracket configured to receive a portion of a joist therein; and a fastener extendible through the brace foot and into contact with the joist to securely connect the brace foot thereto.
- 4. The scaffold unit of claim 3, wherein each leg comprises a main body having a first end telescopically and slidably received within an upper riser, and a second end telescopically and slidably received within a lower riser, the main body and upper and lower risers having alignable adjustment apertures for receipt of a locking pin.
- 5. The scaffold unit of claim 3, wherein each crossbar is comprised of a tubular first segment which telescopically and slidably receives a second segment, the first and second segments including alignable adjustment apertures for receipt of a locking pin therethrough.
- 6. The scaffold unit of claim 3, wherein the brace is comprised of a first tube that telescopically and slidably receives a second tube, the first and second tubes including alignable adjustment apertures for receipt of a locking pin therethrough.
- 7. A joist scaffold unit, comprising:first and second vertical legs of adjustable length disposed generally parallel to one another, wherein each leg comprises a main body having a first end telescopically and slidably received within an upper riser, and a second end telescopically and slidably received within a lower riser, the main body and upper and lower risers having alignable adjustment apertures for receipt of a locking pin; horizontal crossbars of adjustable length extending between the first and second legs, wherein each crossbar is comprised of a tubular first segment which telescopically and slidably receives a second segment, the first and second segments including alignable adjustment apertures for receipt of a locking pin therethrough; a foot pivotally attached to a bottom end of each leg, and including a generally U-shaped bracket configured to receive a portion of a joist therein; a fastener extendible through the foot and into contact with the joist to securely connect the foot thereto; a brace of adjustable length extending from the leg or the crossbar at a first end thereof, wherein the brace is comprised of a first tube that telescopically and slidably receives a second tube, the first and second tubes including alignable adjustment apertures for receipt of a locking pin therethrough; a foot pivotally attached at a second end of the brace and including a generally U-shaped bracket configured to receive a portion of a joist therein; and a fastener extendible through the brace foot and into contact with the joist to securely connect the brace foot thereto.
US Referenced Citations (10)