U.S. patent number RE37,797 [Application Number 09/553,414] was granted by the patent office on 2002-07-23 for truss assembly apparatus with independent roller drive.
This patent grant is currently assigned to MiTek Holdings, Inc.. Invention is credited to Christopher L. Haase.
United States Patent |
RE37,797 |
Haase |
July 23, 2002 |
Truss assembly apparatus with independent roller drive
Abstract
Methods and apparatus for assembling a truss are described. In
one embodiment, the truss table apparatus includes a truss table
and a roller assembly. The truss table includes two guides and a
worksurface which supports the truss members as nailing plates are
pressed into the truss members. The guides are coupled to opposing
sides of the truss table and are substantially C-shaped. The roller
assembly is movably coupled to the truss table guides and includes
a roller for pressing the nailing plates into the truss members.
The roller assembly also includes a plurality of drive wheels that
rest on the truss table guides to move the roller assembly relative
to the truss table. The roller assembly further includes a
plurality of pressure wheels rotatably coupled to the truss table
to maintain the proper spacing between the roller and the truss
table worksurface during pressing of the nailing plates. The
apparatus also includes at least one camber tube and at least one
outer rail for clamping the truss to the worksurface prior to
pressing the nailing plates into the truss members.
Inventors: |
Haase; Christopher L. (Elburn,
IL) |
Assignee: |
MiTek Holdings, Inc.
(Wilmington, DE)
|
Family
ID: |
25491286 |
Appl.
No.: |
09/553,414 |
Filed: |
April 20, 2000 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
Reissue of: |
951116 |
Oct 15, 1997 |
05933957 |
Aug 10, 1999 |
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Current U.S.
Class: |
29/897.31;
100/913; 269/910; 29/432; 29/798 |
Current CPC
Class: |
B27F
7/155 (20130101); Y10T 29/49833 (20150115); Y10S
269/91 (20130101); Y10T 29/5343 (20150115); Y10T
29/49625 (20150115); Y10S 100/913 (20130101) |
Current International
Class: |
B27F
7/15 (20060101); B27F 7/00 (20060101); B23P
011/00 () |
Field of
Search: |
;29/798,897.31,432
;100/210,913 ;227/152 ;269/910 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
1994 brochure entitled, "MiTek Floor Truss Roller" published by
MiTek Industries, Inc., St. Louis, Missouri. .
MiTek MARK V.TM. Gantry System, 4 pgs., 1993. .
Mitek Roller Gantry Roller Press System, 4 pgs., 1994. .
Mitek RailRider.TM. Trackless Floor Truss RollerSystem, 4 pgs.,
1997. .
Mitek Floor Truss Roller, 2 pgs., 1994. .
G2640 Floor Gantry, Klaisler Mfg. Corp., 2 pgs., undated but
predates invention. .
G640 Floor Gantry, Klaisler Mfg. Corp., 2 pgs., undated but
predates invention..
|
Primary Examiner: Hughes; S. Thomas
Assistant Examiner: Jimenez; Marc
Attorney, Agent or Firm: Senniger, Powers, Leavitt &
Roedel
Claims
I claim:
1. A truss table apparatus for use in connection with assembling a
truss, the truss having a plurality of wooden truss members and a
plurality of nailing plates, said truss table apparatus comprising:
a truss table comprising at least two guides .[.coupled to.].
.Iadd.mounted on and supported by .Iaddend.said truss table and a
worksurface on which the truss may be positioned.Iadd., said truss
table guides being disposed at a lower level than the
worksurface.Iaddend.; and a roller assembly movably coupled to said
truss table guides, said roller assembly configured to press the
nailing plates into the truss members, said roller assembly
comprising a plurality of drive wheels .Iadd.engageable with said
truss table guides .Iaddend.for moving said roller assembly
.Iadd.substantially horizontally .Iaddend.relative to the truss
table worksurface.
2. A truss table apparatus in accordance with claim 1 wherein each
said truss table guide comprises a C-shaped channel member having a
top and a bottom.
3. A truss table apparatus in accordance with claim 2 wherein said
.[.plurality of.]. drive wheels are configured to extend into said
C-shaped side channel members.
4. A truss table apparatus in accordance with claim 3 wherein said
roller assembly comprises four drive wheels.
5. A truss table apparatus in accordance with claim 3 wherein said
roller assembly further comprises a roller and a motor, said roller
configured to press the nailing plates .[.in.]. .Iadd.into
.Iaddend.the truss members, said motor configured to be rotatably
coupled to said roller and said drive wheels.
6. A truss table apparatus in accordance with claim 5 wherein said
roller and said drive wheels rotate at a same speed.
7. A truss table apparatus in accordance with claim 2 wherein said
truss table further comprises a wheel flange coupled to each said
channel member bottom, and wherein said .[.to.]. roller assembly
comprises a plurality of pressure wheels configured to be placed
against said wheel flanges when said roller assembly becomes
adjacent to the truss.
8. A truss table apparatus in accordance with claim 1 wherein said
truss table comprises two camber tubes movably coupled to said
truss table worksurface for clamping the truss members to said
worksurface.
9. A truss table apparatus in accordance with claim 8 wherein said
truss table further comprises a plurality of camber connection
slots extending through said worksurface, a plurality of camber
cylinders positioned below said truss table worksurface, and a
plurality of camber connecting plates extending through said
connection slots and coupled to said tubes and said cylinders.
10. A method of assembling a truss utilizing a truss table
apparatus, the truss having a first surface, a second surface, at
least two truss members, and a plurality of nailing plates, the
nailing plates configured to couple the truss members, the truss
table apparatus including a truss table having at least two guides
.Iadd.mounted on and supported by the truss table .Iaddend.and a
worksurface, and a roller assembly movably coupled to the truss
table guides .Iadd.generally below the level of the
worksurface.Iaddend., the roller assembly comprising a motor, a
roller, and a plurality of drive wheels, said method comprising the
steps of: positioning the truss members on the truss table
apparatus so that the truss second face lies on the truss table
worksurface; positioning at least one nailing plate over the truss
member first surface; pressing the nailing plate into the truss
members with the roller assembly by activating the motor so that
.[.and.]. the drive wheels .Iadd.engage said truss table guides and
.Iaddend.move the roller assembly .Iadd.substantially horizontally
.Iaddend.relative to the truss table; repositioning the truss so
that the truss first surface lies on the truss table worksurface;
positioning at least one nailing plate over the truss member second
surface; and pressing the nailing plate into the truss members with
the roller assembly by activating the motor so that .[.and.]. the
drive wheels .Iadd.engage said truss table guides and .Iaddend.move
the roller assembly .Iadd.substantially horizontally
.Iaddend.relative to the truss table.
11. A method in accordance with claim 10 wherein pressing the
nailing plate into the truss members with the roller assembly
comprises the step of moving the roller assembly between the ends
of the truss table apparatus.
12. A method in accordance with claim 11 wherein the roller
assembly includes a plurality of pressure wheels, and wherein
moving the roller assembly between the ends of the truss table
apparatus further includes the step of positioning the pressure
wheels adjacent to the guides so that the roller assembly is
properly spaced from the truss table worksurface.
13. A method in accordance with claim 10 wherein the truss table
apparatus includes a movable camber tube and an outer rail, and
wherein positioning the truss members on the truss table apparatus
so that the truss second face lies on the truss table worksurface
further comprises the step of moving the camber tube towards the
outer rail so that the truss is clamped to the truss table
worksurface.
14. A method in accordance with claim 13 wherein the truss table
apparatus includes a plurality of slots extending through the truss
table worksurface and a plurality of cylinders positioned below the
worksurface and coupled to the truss table and the camber tube, and
wherein moving the camber tube towards the outer rail comprises the
step of activating the cylinder so that the camber tube moves
toward the outer rail.
15. A method in accordance with claim 13 wherein the truss table
apparatus includes a second movable camber tube and a second outer
rail, and wherein positioning the truss members on the truss table
apparatus so that the truss first face lies on the truss table
worksurface further comprises the step of moving the second camber
tube towards the second outer rail so that truss is clamped to the
truss table worksurface.
16. A method in accordance with claim 10 wherein positioning at
least one nailing plate over the truss member second surface and
pressing the nailing plates into the truss members with the roller
assembly comprises the step of moving the roller assembly between
the ends of the truss table apparatus..[.
17. A roller apparatus for use in connection with assembling a
truss on a truss table, the truss having a plurality of wooden
truss members and a plurality of nailing plates, the truss table
having at least two guides and a worksurface, said roller apparatus
comprising: a frame; a roller coupled to said frame configured to
press the nailing plates into the truss members; and a plurality of
drive wheels coupled to said frame configured to movably couple to
the truss table guides..]. .[.
18. A roller apparatus in accordance with claim 17 further
comprising a plurality of pressure wheels coupled to said frame
configured to rotatably couple to said truss table..]..[.
19. A roller apparatus in accordance with claim 18 wherein said
roller and said drive wheels rotate at a same speed..]..Iadd.
20. A truss table apparatus as set forth in claim 1 wherein said
truss table guides are supported by the truss table out of contact
with a floor supporting the apparatus, there being a space free of
solid material under each guide..Iaddend..Iadd.
21. A truss table apparatus in accordance with claim 20 wherein
each truss table guide opens laterally outwardly away from the
truss table..Iaddend..Iadd.
22. A truss table apparatus in accordance with claim 1 wherein the
drive wheels are frustoconically shaped..Iaddend..Iadd.
23. A truss table apparatus for use in assembling a truss, the
assembled truss having wooden truss members and nailing plates
interconnecting the truss members, said truss table apparatus
comprising: a truss table comprising a worksurface on which the
truss members and nailing plates may be positioned, and guides
mounted on and supported by said truss table at a location lower
than the worksurface; and a roller assembly including a roller
supported by the roller assembly for rolling over the truss members
and nailing plates to press the nailing plates into the truss
members, and a plurality of drive wheels engageable with said truss
table guides at a location lower than the worksurface for moving
said roller assembly substantially horizontally relative to the
worksurface..Iaddend..Iadd.
24. A truss table apparatus as set forth in claim 23 wherein said
truss table guides are supported by the truss table out of contact
with a floor supporting the apparatus..Iaddend..Iadd.
25. A truss table apparatus in accordance with claim 23 wherein
each truss table guide opens laterally outwardly away from the
truss table..Iaddend..Iadd.
26. A truss table apparatus in accordance with claim 25 wherein
each of said drive wheels is received laterally into one of said
truss table guides..Iaddend..Iadd.
27. A truss table apparatus as set forth in claim 23 wherein said
roller assembly further comprises a motor adapted to drive rotation
of the roller and the drive wheels..Iaddend..Iadd.
28. A truss table apparatus in accordance with claim 27 wherein the
motor includes a drive shaft rotatably coupled to the drive wheels
for driving rotation thereof..Iaddend..Iadd.
29. A truss table apparatus in accordance with claim 23 wherein
said truss table further comprises two camber tubes mounted on the
truss table for movement relative to said truss table worksurface
for clamping the truss members on said
worksurface..Iaddend..Iadd.
30. A truss table apparatus in accordance with claim 29 wherein
said truss table further comprises camber connection slots
extending through said worksurface, camber cylinders positioned
below said truss table worksurface, and camber connecting plates
extending through said connection slots and coupled to said tubes
and said cylinders..Iaddend..Iadd.
31. A truss table apparatus in accordance with claim 23 wherein the
guides are mounted on sides of the truss table..Iaddend..Iadd.
32. A truss table apparatus in accordance with claim 23 wherein the
truss table comprises a truss table top and legs extending down
from and supporting the truss table top, each leg having an upper
end adjacent to the truss table top and a lower end opposite the
top end, the guides being mounted on the truss table at a location
spaced above the lower ends of the legs..Iaddend.
Description
FIELD OF THE INVENTION
This invention relates generally to an apparatus for use in the
manufacture of trusses and, more particularly, to methods and
apparatus for assembling a prefabricated truss.
BACKGROUND OF THE INVENTION
Prefabricated trusses are often used in the construction of
building structures because of their strength, reliability, low
cost, and ease of use. The trusses are typically assembled in a
factory using machinery for mass-fabrication of individual truss
components. The trusses are assembled, for example, on large
assembly tables and then shipped to construction sites.
A prefabricated truss typically includes truss members coupled by
nailing plates. Each truss member has a first surface and a second
surface, and the truss members are pre-cut for a predefined truss
configuration. In assembling the truss, the truss members are
arranged on a long truss assembly table and nailing plates are
placed over the first surface of the truss members. The plates are
then pressed into the truss members using, for example, a roller or
a vertical press. The truss is then manually flipped over and
nailing plates are positioned over the second face of the truss
members and pressed thereto. The completed truss is then removed
from the assembly table.
Modern gantry presses, or roller presses, include a gantry frame
that travels on two guide tracks mounted to the floor along each
side of the truss table. A roller is mounted to the gantry frame at
a predetermined distance above a truss table worksurface so that as
the gantry frame is moved along the guide tracks, the roller
presses the nailing plates into the truss members. The gantry press
typically presses the nailing plates into the wood truss members to
a depth of 50-80% of the total length of the nailing plate
projections. The truss may then be passed through a finishing
press, which includes a pair of nip rollers, to fully press the
nailing plates into the truss members.
The installation of the gantry press guide tracks is critical in
the proper operation of the gantry press. In a typical
installation, the guide tracks are spaced away from the sides of
the truss table to provide adequate clearance for the gantry press.
Since the gantry press rides on the guide tracks, the tracks must
be level and true with respect to the truss table worksurface. Due
to the size and weight of the gantry press, the guide tracks must
be securely fastened to the floor and made of a suitable material,
typically, steel. During use of the truss table, an operator is
required to place the truss members and nailing plates on the truss
table worksurface, requiring the operators to step over the guide
tracks, if possible, or stand farther from the table and extend the
truss members and nailing plates an additional distance. Due to the
size and spacing of the guide tracks, easy access to the truss
table worksurface is impeded and throughput is reduced.
It would be desirable to provide an apparatus which enables
fabricating a truss without requiring that guide tracks be placed
on the floor next to the truss table. It would also be desirable to
provide an apparatus which does not require a finishing roller to
fully press in the nailing plates.
SUMMARY OF THE INVENTION
These and other objects may be obtained by a truss assembly
apparatus which, in one embodiment includes a substantially
rectangular shaped truss table having two longitudinal sides, a
worksurface, and two ends. Each longitudinal side includes a
substantially C-shaped elongate member, or guide, extending the
length of the truss table. At least one camber tube and at least
one outer rail are provided to clamp the truss members in position
over the worksurface.
The apparatus also includes a roller assembly for pressing the
nailing plates into the truss members. The roller assembly includes
a substantially cylindrical shaped roller and a substantially
inverted U-shaped frame. The roller is rotatably coupled to the
frame and sized to press the nailing plates in to the truss members
as roller assembly moves between the ends of the truss table. The
roller assembly further includes a plurality of drive wheels and a
plurality of pressure wheels. Each substantially frustro-conical
shaped drive wheel is coupled to the frame and sized to rest on a
truss table guide to move the roller assembly relative to the truss
table. Each pressure wheel is substantially spool shaped and
movably coupled to the frame and sized to rest against the truss
table when the roller is adjacent to the truss. A motor is coupled
to the roller and the drive wheels to drive the roller and the
drive wheels at the same speed. The apparatus moves between the
ends of the truss table by rotation of the roller and the drive
wheels.
To fabricate a truss using the above described truss assembly
apparatus, the truss members are positioned on the truss table
worksurface. A first camber tube is then moved toward a first outer
rail to clamp, or trap, the truss members in place. The nailing
plates are then positioned over the truss member first surfaces and
are pressed into the truss members using the roller assembly.
Specifically, the roller assembly roller presses the nailing plates
into the truss members by moving between the ends of the truss
table. The roller assembly is moved by energizing the motor so that
the roller and drive wheels rotate. The drive wheels move the
roller assembly relative to the truss table until the roller is
adjacent the truss members. After the roller is adjacent to the
truss members, the roller rolls onto the first surface of the truss
and the nailing plates. The nailing plates are fully pressed into
the truss members as a result of proper roller and pressure wheel
spacing. The roller is spaced above the worksurface so that as the
roller rolls onto the nailing plates the roller assembly is raised.
This raised position removes the drive wheels from the guides and
places the weight of the entire roller assembly on the nailing
plates. Additionally, as the roller assembly is raised, the
pressure wheels are placed against the truss table so that the
upward movement of the roller assembly is limited. While the roller
assembly is in the raised position, the rotation of the roller
against the truss members and the nailing plates moves the roller
assembly relative to the table. After traveling the entire length
of the truss, the roller assembly will drop slightly as the roller
rolls off the truss so that the drive wheels are placed against the
guides. The drive wheels then continue movement of the roller
assembly until stopped by the operator or the roller assembly
reaches the end of the truss table. The first camber tube is then
moved away from the truss members so that the members are no longer
clamped in place and the truss is flipped over and placed on the
worksurface between a second camber tube and a second outer rail.
The second camber tube is moved toward the truss so that the truss
is clamped between the camber tube and the outer rail and the
nailing plates are positioned over the truss members. After
reversing the rotational direction of the motor, the roller
assembly is moved between the ends of the truss table in the manner
described above so that the nailing plates are press into the truss
members. The second camber tube is then moved away from the truss
members so that the truss is no longer clamped in place. The truss
is then removed from the truss assembly.
The above described apparatus facilitates fabricating a truss
without requiring floor mounted guide tracks. In addition, such
apparatus presses the nailing plates into the truss members without
requiring a finishing press, therefore saving time.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an end view of a truss assembly apparatus in accordance
with one embodiment of the present invention.
FIG. 2 is a side view of the truss assembly apparatus shown in FIG.
1, with parts cut-away from the roller assembly.
FIG. 3 is a top view of the truss assembly apparatus shown in FIG.
1.
DETAILED DESCRIPTION
FIG. 1 is an end plan view of a truss assembly apparatus 20 in
accordance with one embodiment of the present invention. Truss
assembly apparatus 20 includes truss table 24, roller assembly 28,
camber tubes 32A and 32B, and outer rails 36A and 36B. Truss table
24 includes respective guides, or side channels, 40A and 40B, first
and second sides 42A and 42B, a worksurface 44, beam legs 48, stops
50A, 50B, 50C and 50D (only two shown in FIG. 1), and wheel flanges
52A and 52B. Side channels 40A and 40B are substantially C-shaped
having respective top and bottom webs 53A and 53B and 54A and 54B.
Channels 40A and 40B are coupled to respective truss table first
and second sides 42A and 42B and extend the length of truss table
24 below worksurface 44. Beam legs 48 are substantially elongate
members extending from truss table 24 to a floor 56. Stops 50A,
50B, 50C, and 50D are substantially elongate members sized to stop
movement of roller assembly 28. Stops 50A, 50B, 50C, and 50D are
coupled to truss table 24 and are made of steel or similar
material. Wheel flanges 52A and 52B are substantially elongate
members extending the length of truss table 24 and are coupled to a
bottom of respective side channel bottom webs 54A and 54B.
Roller assembly 28 includes a frame 58, a roller 60, four drive
wheel 68A, 68B, 68C, and 68D (only two shown in FIG. 1), and four
pressure wheels 70A, 70B, 70C, and 70D (only two shown in FIG. 1).
Frame 58 includes first and second end portions 72A and 72B, and
top portion 76 coupled between end portions 72A and 72B. First and
second end portions 72A and 72B and top portion 76 are
substantially rectangular shaped. Roller 60 is substantially
cylindrical shaped with a center shaft 80 extending from roller
first and second ends 84A and 84B. Roller 60 is made of steel or
similar material to apply necessary compressive force without
significant flexing. Roller shaft 80 is rotatably coupled to
take-up bearings 88A and 88B. Take-up bearings 88A and 88B are
movably coupled to frame ends 72A and 72B. Substantially
frustro-conical shape drive wheels 68A and 68C, and 68B and 68D
extend into respective channels 40A and 40B. Drive wheels 68A, 68B,
68C, and 68D are rotatably coupled to frame 58 and sized to ride on
channel member bottom webs 52A and 52B. Pressure wheels 70A, 70B,
70C and 70D are substantially spool shaped and movably coupled to
frame 58. Pressure wheels 70A and 70C, and 70B and 70D are sized to
be placed adjacent to respective wheel flanges 52A and 52B to
maintain proper spacing between roller 60 and worksurface 44.
Camber tubes 32A and 32B and outer rails 36A and 36B are
substantially elongate members movably coupled to worksurface
44.
Referring to FIG. 2, roller assembly 28 further includes a motor
100, a motor mounting plate 104, a roller sprocket 108, a roller
chain 112, and two roller adjustment subassemblies 116A and 116B
(only one shown in FIG. 2). Motor 100, for example, a bidirectional
electric motor, is coupled to frame 58 using mounting plate 104.
Roller sprocket 108 is coupled to roller shaft 80. Roller sprocket
108 is rotatably coupled to motor 100 using roller chain 112. Motor
100 is movably coupled to mounting plate 104 so that tension of
roller chain 112 may be adjusted. Roller adjustment subassemblies
116A and 116B are coupled to respective take-up bearings 84A and
84B so that roller 60 may be adjusted up and down relative to
worksurface 44. In addition, roller assembly 28 includes drive
sprockets 118A and 118B (only one shown in FIG. 2), four drive
wheel sprockets 120A, 120B, 120C, and 120D (only two shown in FIG.
2), first and second drive chains 124A and 124B (only one shown in
FIG. 2), two chain take-up subassemblies 128A and 128B (only one
shown in FIG. 2), and a mast 132. Drive sprockets 118A and 188B are
coupled to roller shaft 80 at respective roller ends 84A and 84B.
Drive wheels 68A and 68C are rotatably coupled to roller 60 using
drive sprocket 118A, drive wheel sprockets 120A and 120C, and drive
chain 124A. Drive wheels 68B and 68D are similarly rotatably
coupled to roller 60 using drive sprocket 118B, wheel sprockets
120B and 120D, and second drive chain 124B. Sprockets 118A, 118B.
120A, 120B, 120C, and 120D are sized so that roller 60 and drive
wheels 68A, 68B, 68C, and 68D rotate at a same speed. Tension of
first drive chain 124A is adjusted using chain take-up subassembly
128A. Tension of second drive chain 124B is similarly adjusted
using chain take-up subassembly 128B. Mast 132 is a substantially
elongate member coupled to frame 58 to support power source
interconnections (not shown) to truss table apparatus 20.
FIG. 3 is a top plan view of a truss table apparatus 20. Truss
table 24 further includes first and second ends 156A and 156B,
camber connection slots 160A, 160B, 160C, 160D, 160D, 160E, and
160F extending through worksurface 44, actuators 164A, 164B, 164C,
164D, 164E, and 164F positioned below truss table worksurface 44,
and connecting plates 168A, 168B, 168C, 168D, 168E, and 168F. In
one embodiment, actuators 164A, 164B, 164C, 164D, 164E, and 164F
are pneumatic cylinders sized to position respective camber tubes
32A and 32B toward or away from respective outer rails 36A and 36B.
Cylinders 164A, 164B, 164C, 164D, 164E, and 164F are coupled
between truss table 24 and respective connecting plates 168A, 168B,
168C, 168D, 168E, and 168F. Connecting plates 168B, 168D, and 168F
extend through respective connection slots 160B, 160D, and 160F and
are coupled to camber tube 32A. Connecting plates 168A, 168C, and
168E extend through respective connection slots 160A, 160C, and
160E and are coupled to camber tube 32B. A truss 196 includes truss
members 200A, 200B, 200C, 200D, 200E, 200F, 200G and 200H and
nailing plates 204A, 204B, 204C, 204D, 204E, 204F, and 204G. Truss
196 includes a first surface 208 and a second surface (not
shown).
Generally, truss members 200A, 200B, 200C, 200D, 200E, 200F, 200G
and 200H are placed on truss table 24 and nailing plates 204A,
204B, 204C, 204D, 204E, 204F, and 204G are placed over upwardly
facing truss first surface 208. Nailing plates 204A, 204B, 204C,
204D, 204E, 204F, and 204G are then pressed into truss members
200A, 200B, 200C, 200D, 200E, 200F, 200G, and 200H using roller
assembly 28. Truss 196 is then flipped over, and nailing plates
(not shown) are placed over truss second surface (not shown) and
pressed into truss members 200A, 200B, 200C, 200D, 200E, 200F,
200G, and 200H using roller assembly 28. More particularly, truss
members 200A, 200B, 200C, 200D, 200E, 200F, 200G, and 200H are
positioned on truss table worksurface 44 between camber tube 32A
and outer rail 36A. Camber tube 32A is moved toward outer rail 36A
by activating cylinders 164B, 164D, and 164F so that truss members
200A, 200B, 200C, 200D, 200E, 200F, 200G, and 200H are clamped
therebetween. Nailing plates 204A, 204B, 204C, 204D, 204E, 204F,
and 204G are then placed over the truss member intersections (not
shown) and pressed into truss members 200A, 200B, 200C, 200D, 200E,
200F, 200G, and 200H by moving roller assembly 28 between truss
table ends 156A and 156B. Specifically, motor 100 is energized so
that roller chain 112 rotates roller 60. Rotation of roller 60
results in movement of first and second drive chains 124A and 124B
so that drive wheels 68A, 68B, 68C, and 68D rotate. The rotation of
drive wheels 68A, 68B, 68C, and 68D against side channels 40A and
40B move roller assembly 28 relative to truss table 24. In one
embodiment, roller assembly 24 begins at truss table end 156A and
moves to end 156B. When roller 60 becomes adjacent to truss members
200A, 200B, and 200C, roller 60 rolls onto truss first surface 208
and nailing plates 204A and 204B so that roller assembly 28 is
raised by the thickness of nailing plates 204A and 204B. As roller
assembly 28 is raised, drive wheels 68A, 68B, 68C, and 68D become
spaced from side channel bottom webs 54A and 54B and pressure
wheels 70A, 70B, 70C, and 70D become adjacent to wheel flanges 52A
and 52B. Pressure wheels 70A, 70B, 70C, and 70D limit the upward
movement of roller assembly 28 to the thickness of nailing plates
204. After drive wheels 68A, 68B, 68C, and 68D are removed from
channels 40A and 40B, movement of roller assembly 28 results from
rotation of roller 60 against truss 196. Upon roller 60 becoming
adjacent to nailing plates 204A and 204B, the forward movement and
weight of roller 60 fully press projections of nailing plates 204A
and 204B into truss members 200A, 200B, and 200C. Roller assembly
28 continues moving towards truss table end 156B and presses in
nailing plates 204C, 204D, 204E, 204F, and 204G in a manner similar
to nailing plates 204A and 204B. When roller 60 moves beyond truss
196, roller assembly 28 drops by the thickness of nailing plates
204F and 204G and drive wheels 68A, 68B, 68C, and 68D are placed on
side channel bottom webs 54A and 54B so that roller assembly 28
continues moving toward end 156B. Motor 100 is de-energized when
roller assembly 28 becomes adjacent to stops 52C and 52D.
Camber tube 32A is then moved away from truss 196 using cylinders
164B, 164D, and 164F. Truss 196 is flipped over so that truss first
surface 208 is adjacent to worksurface 44 and positioned between
second camber tube 32B and outer rail 36B. Cylinders 164A, 164C,
and 164E are activated so that camber tube 32B is moved toward
outer rail 36B clamping truss 196 between tube 32B and rail 36B.
Second face nailing plates (not shown) are positioned at truss
member intersections (not shown). The rotational direction of motor
100 is then reversed so that roller assembly 28 moves toward truss
table end 156A when energized. Upon energizing motor 100, drive
wheels 68A, 68B, 68C, and 68D move roller assembly 28 relative to
truss table 24. Upon roller 60 becoming adjacent to truss 196
roller 60 rolls onto the truss second surface and the second
surface nailing plates so that roller assembly 28 will be slightly
raised. Raising, roller assembly 28 spaces drive wheels 68A, 68B,
68C, and 68D from side channels 40A and 40B and places pressure
wheels 70A, 70B, 70C, and 70D adjacent to wheel flanges 52A and
52B. Rotation of roller 60 moves roller assembly 28 relative to
truss table 24 and presses the second face nailing plates (not
shown) into truss 196 in a manner similar to nailing plates 204A,
204B, 204C, 204D, 204E, 204F, and 204G. Upon roller 60 moving
beyond truss 196, roller 60 rolls off truss 196 lowering roller
assembly 28 and placing drive wheels 68A, 68B, 68C, and 68D
adjacent to side channels 40A and 40B. Drive wheels 68A, 68B, 68C,
and 68D continue moving roller assembly 28 toward end 156A until
adjacent to stops 50A and 50B and motor 100 is de-energized. Camber
tube 32B is then moved away from truss 196 using cylinders 164A,
164C, and 164E. Truss 196 is then be removed from truss table
apparatus 20.
If the nailing plates, for example, nailing plates 204A, 204B,
204C, 204D, 204E, 204F, and 204G are not properly pressed into
truss 196, several adjustments can be made. To function properly,
roller 60 must be properly spaced above worksurface 44. Roller 60
is adjusted using roller adjustment subassemblies 116A and 116B so
that roller 60 is spaced from worksurface 44 a distance equal to
the thickness of truss 196 plus the thickness of a nailing plate
excluding the projections, such as nailing plate 204A. For example,
in assembling a floor truss, a typical 2.times.4 truss member is
positioned on worksurface 44 in the 4.times.2 orientation with the
truss member thickness approximately three and one-half inches. A
typical nailing plate excluding the projections is one-sixteenth of
an inch. As a result, roller 60 is spaced three and nine-sixteenths
of an inch above worksurface 44. Specifically, chain take-up
subassemblies 128A and 128B are adjusted so that drive chains 124A
and 124B are loose. Roller adjustment subassemblies 116A and 116B
are then adjusted so that roller 60 is moved the proper distance
from worksurface 44. Roller 60 must be parallel to worksurface 44
and properly spaced after completion of adjustment of roller
adjustments 116A and 116B. After completing adjustments of roller
adjustment subassemblies 116A and 116B, chain take-up subassemblies
128A and 128B are adjusted to properly tension drive chains 124A
and 124B. Additionally, pressure wheels 70A, 70B, 70C, and 70D may
require adjustment so that spacing between wheel flanges 52A and
52B is equal to the thickness of a nailing plate excluding the
projections, for example, nailing plate 204A. Using the
above-described example, pressure wheels 70A, 70B, 70C, and 70D
would be spaced one-sixteenth of an inch from wheel flanges 52A and
52B. Specifically, pressure wheels 70A, 70B, 70C, and 70D are
repositioned relative to frame 58 so that pressure wheels 70A, 70B,
70C, and 70D are properly spaced from wheel flanges 52A and 52B.
Proper spacing of roller 60 and pressure wheels 70A, 70B, 70C, and
70D ensure proper installation of nailing plates 204A, 204B, 204C,
204D, 204E, 204F, and 204G. If roller chain 112 tension is
improperly adjusted, motor 100 may be repositioned relative to
mounting plate 104 until roller chain 112 is properly adjusted.
The above-described apparatus facilitates fabricating a truss
without requiring guide tracks be coupled to the floor. In
addition, such apparatus presses the nailing plates into the truss
without requiring a finishing press or other action.
From the preceding description of various embodiments of the
present invention, it is evident that the objects of the invention
are attained. Although the invention has been described and
illustrated in detail, it is to be clearly understood that the same
is intended by way of illustration and example only and is not to
be taken by way of limitation. For example, the truss assembly was
described as a serial process. Such truss table apparatus may,
however, also be utilized to assembly multiple trusses
simultaneously. For example, after pressing the nailing plates into
the truss members and flipping the truss, truss members from a
second truss could be positioned on the truss table worksurface
between the first camber tube and outer rail. The first and second
trusses could then be simultaneously clamped by the camber tubes
and the nailing plates positioned such that the roller presses the
nailing plates into the first and second truss members
simultaneously. After moving the camber tubes, the first completed
truss could be removed from the truss table apparatus and the
second truss could be flipped. This method of operation could
significantly increase production rates. Accordingly, the spirit
and scope of the invention are to be limited only by the terms of
the appended claims.
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