Note: Descriptions are shown in the official language in which they were submitted.
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APPARATUS AND METHOD FOR FEEDING ELONGATED ELEMENTS
BACKGROUND OF' THE INVENTION
1. Field of the Invention
The present invention relates to handling
of elongated elements and, more particularly,
pertains to a material-handling system which is
suitable for use in sawmill operations.
2- Description of the Prior Art
A 7_og entering a sawmi:Ll is initially sawed
into lumber pieces(hereinafter referred to as cants)
having flat ,end parallel top and bottom surfaces but
unfinished l~~ngitudinal side su:_faces or wanes. The
wanes of a cent may be very irre~~ular and are usually
oblique to the top and bottom surfaces thereof.
Accordingly, the cants have tc be run through an
edger to trim the wanes thereof such as to produce
wood pieces having parallel sid° surfaces which are
planar and perpendicular to she top and bottom
surfaces thereof.
Conventional edgers generally comprise
various transfer mechanisms which are adapted to
transversall~.~ transport successive cants through a
scanning station which is adapted to ascertain the
profile of the cants. In accordance with calculations
made on the basis of the profilF~ data, the cants are
conveyed and positioned on an infeed table of an
edging station where the cant: are longitudinally
accelerated. Typically, the infeed gable comprises a
series of driven rollers disposed at regular
intervals along the longitudinal axis of a frame for
supporting a.nd moving the cants and a series of
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overhead pre:~sing rollers adapted to engage the top
surface of the cants. The overhead pressing rollers
are displaceable between inoperative and operative
positions by means of hydraulic cylinders. Brackets
are provided to connect the hy~~raulic cylinders to
the overhead pressing rollers.
Although the conventional mechanisms used
to transfer t:he cants from an ini~ake station, through
a scanning station and then ont« an infeed table of
an edging station perform satisf<~ctorily, it has been
found that there is a need for new and simpler
transfer mechanisms which are adapted to enhance the
productivity of an edging apparatus.
For instance, conventional cant transfer
mechanisms do not allow to fill ~~nwanted gaps between
successive cents resulting from problems during the
loading thereof on an entry conveyor of the edger.
Moreover, actual cant transfer mechanisms
do not permit to change the speed of the production
line accord=_ng to the lengtY: of each incoming
successive cents, although shorter cants require less
time to be processed. Accordingly, this limitation
results in a lost of productivity.
Anc>ther problem associated with the actual
cant transfer mechanisms is the ~~remature wear of the
hydraulic cy_Linders of the overhead pressing rollers
of the edger infeed table. This is mostly
attributable to the vibrations transmitted to the
rollers when the same are in contact with the top
surface of the cants. Furthermore, according to the
above described construction of she pressing rollers,
the travelling speed of the roll.=_rs is limited, since
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relatively severe impacts of the rollers against the
top surfac-~e of the cants can damage the cylinders.
SUMMARY OF TE:E INVENTION
It is therefore an aim of the present
invention to provide an apparatu;~ which is adapted to
feed elonc~ate:d elements.
It is also an aim of t:he present invention
to provide such an apparatus which is adapted to feed
elongated elements at a substantially uniform rate.
It is a further aim of the present
invent10I1 to provide such an ap~~aratus which is well
adapted to cooperate with a scanning station and an
edging station of a wood edger.
It is still an aim of she present invention
to provide transfer mechanisms ~Nhich are adapted to
enhance the ~~roductivity of an ec.ger.
It is still an aim of she present invention
to provide a means for increasing the service life of
an overhead caressing roller.
Therefore, in accordance with the present
invention, tl-iere is provided an ,apparatus for feeding
elongated elements at a substantially uniform rate
comprising a frame having a longitudinal axis,
multiple axially extending conveying means disposed
in laterally spaced relationship on said frame means
and adapted to be selectively driven at various
speeds to move successive incoming transversally
extending elongated elements along said longitudinal
axis such as to provide a regular feeding rate, and
means foz controlling operation of said conveying
means.
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In a more specific construction, said
multiple conveying means are independently and
successively driven to convey ore incoming elongated
elements at a time, thereby allowing to accumulate
one elongated element per conveying means at a
delivery end of said apparatus.
In accordance with an~~ther general aspect
of the prey>ent invention, there is provided an
apparatus fo:r transferring and orienting successive
cants on an infeed table of an edging station. The
apparatus comprises a frame having a longitudinal
axis and at least two axially extending conveying
means disposed in lateral spaced-apart relationship
on said frame for moving success_~ve incoming cants in
a direction transversal to longitudinal axes thereof .
Each convey~_ng means includes first and second
endless driving members. The first and second endless
driving members are respective=_y provided with at
least one first engaging means and with at least one
second engaging means. The first and second engaging
means are adapted to cooperate to convey successive
incoming cants along said longil_udinal axis of said
frame. The first and second engaging means each have
opposed pushing and abutment =sides. The apparatus
further corr.prises reversible motor means for
selective;.y driving said first and second endless
driving members of said conveying means in a forward
direction and a backward direction, and control means
adapted to control the operation of said conveying
means such a:~ to transport successive incoming cants
to the infeed table of the edging station by
alternate~.y wedging the same t~etween said pushing
side of said first engaging means and said abutment
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side of said second engaging means, and between said
pushing side of said second engaging means and said
abutment ;~idE~ of said first engaging means.
In a further construction in accordance
with the pre;~ent invention, the pushing side of each
said firsr_ and second engaging means is provided with
compressible means, whereas said abutment side
thereof is substantially rigid.
In accordance with a further aspect of the
present invention, there is provided a method of
transporting successive elongated elements
transversall~.~ of respective longitudinal axes
thereof. 'The method comprises th~~ steps of: detecting
a first incoming elongated eleme:zt, positioning first
engaging means adjacent a lonc-itudinally extending
upstream si~3e of the first incoming elongated
element, wedding the first incoming elongated element
between said first engaging mean; and second engaging
means located on a downstream side of the first
incoming elongated element, mo,ring said first and
second engaging means in unison so as to transport
said first incoming elongated element to a delivery
location, morning said first and second engaging means
away from said first incoming e~_ongated element such
as to position said first and ~~econd engaging means
on the down;~tream and upstream sides of a second
incoming elongated element, r~=_spectively, whereby
said first and second engaging means alternately
serve to push and retain the successive incoming
elongated elements.
In accordance with a further aspect of the
present invention there is provided an infeed table
of an edging station adapted to cut away unfinished
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lengthwise extending wane surfaces of a cant to
produce a dimensioned product. as the cant is
displaced therethrough along ,~ prescribed edging
path. The infeed table comprises infeed conveyor
means for longitudinally displacing the cant into the
edging station along the edging path, said infeed
conveyor mea:zs including a supporting surface and a
plurality of overhead roller pressing units, each
said overhead roller pressing unit including first
and second frame members pivotally mounted on a
common pivot, said first frame member supporting a
roller adapted to roll on the top surface of the
cant, dampin~~ means disposed between said first and
second frame members to absorb vibrations transmitted
to said roller, and means for acting on said second
frame member to displace said roller between an
inoperative position wherein said roller is out of
engagement. with the cant and an operative position
wherein said roller engages a top surface of the
cant.
In accordance with a further aspect of the
present invention there is provided an apparatus for
feeding one element at a time, c~~mprising frame means
defining a longitudinal axis, a series of conveyors
supported by said frame means and adapted to move
incoming elements in a feeding direction parallel to
said longitudinal axis, sensing means for detecting
the space bEtween successive incoming elements, and
control rnear.,s coupled to said sensing means and
adapted to operate said conveyors to create a
differential of speed between said conveyors such as
to provide a desired spacing bet~~een the elements.
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In accordance with a further aspect of the
present invention there is provided a method for
feeding one element at a time, wherein the elements
are conveyed along a feeding direction by a series of
conveyors, comprising the steps of: ascertaining the
spacing bet=ween successive incoming elements,
generating related spacing data, and on the basis of
said spacing data, creating a c.ifferential of speed
from one conveyor to another to provide a desired
spacing between the elements.
BRIEF DESCRIPTION OF THE DRAWING~~
Hazing thus generally described the nature
of the prese.zt invention, reference will now be made
to the accompanying drawings, showing by way of
illustration a preferred embodiment thereof, and in
which:
Fic~. 1 is a schematic top plan view of a
wood edges in accordance with the present invention;
Fic~. 2 is a schematic side elevational view
of the wood edges of Fig. l;
Fic~. 3 is a schematic top plan view of a
scanner delivery station of the mood edges of Fig. l;
Fic~. 4 is a top plan z~iew of one module of
a positioning apparatus of the wood edges;
Fic~. 5 is fragmentary cross-sectional view
taken along lines 5-5 of Fig.4 and showing the
construction of a cant engaging member thereof;
Fic~. 6 is a simplified end elevational view
of the module of Fig. 4, showing the disposition of
two rollers of an edges infeeo table with respect
thereto;
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Fic~s. 7a to 7d ~~re schematic side
elevational views of the po;~itioning apparatus,
illustrating the sequence of operations thereof;
Fic~s. 8a and 8b are s:~de elevational views
of an overhead pressing roller of the edger infeed
table respectively shown in an inoperative position
and an operative position thereof; and
Fic~. 9 is a top plan view of the pressing
roller o:~ Fic~s 8a and 8b.
DESCRIPTION C)F THE PREFERRED EMBODIMENTS
Now referring to ths~ drawings, and in
particular t:o Figs. 1 and 2, a wood edger in
accordance with the present invention and generally
designated b~.~ numeral 10 will be described.
The wood edger 10, as will be explained
hereinafter, is adapted t« cut away the
irregularities or flaws left on the longitudinal side
surfaces of elongated wood piece: or cants C cut from
debarked log;. Accordingly, cants C having flat and
parallel top and bottom surf~~ces and unfinished
lengthwise e:Ktending wane surfa~~es may be converted
into finished pieces having parallel side surfaces
which are p:Lane and perpendicular to the top and
bottom surfaces thereof.
Ba:>ically, the wood edger 10 comprises a
number of transfer or feeder mechanisms which are
adapted to transversally transfer successive cants C
from an inta~te station 12, through a scanning station
14, and them onto an infeed table 16 of an edging
station ~8 where the cants C are longitudinally
accelerated.
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The scanning station 1~~ detects the profile
of the cants C and generates related data which are
processed by a control system (not shown) to
determine the position of the circular-saws (not
shown) of th.e edging stations ~.8 and to adjust the
orientation of the cants C on the infeed table 16
before being fed through the edging station 18. This
permits to minimise the amount of material to be
trimmed so as to produce the largest possible
product.
As seen in Figs. 1 and 2, the intake
station 12 includes two consecutive inclined multiple
chain conve~rors 20 and 22. The multiple chain
conveyor 20 comprises a number of parallel endless
chains 24 which are driven in unison by means of
driving sprockets engaged with the endless chains 24
at the delivery end of the first multiple chain
conveyor 20. Similarly, the multiple chain conveyor
22 is provi~3ed with a number of parallel endless
chains 28 ~n~hich are driven by means of driving
sprockets 30 engaged with the chains 28 at the
delivery end of the multiple chain conveyor 22. The
cants C to be processed are transversally dragged one
by one along the supporting surfaces of the inclined
multiple chain conveyors 20 and 22 by attachments
inserted at intervals in the endless chains 24 and
28. Lateral guide plates 32 are also provided along
the sides of the multiple chain conveyors 20 and 22
to keep the cants C from running off.
The cants C are then successively
transferred to an aligning sedation 34 where an
operator may intervene to remove non-desired cants
and properly position the same if need be. The
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aligning station 34 consists of an horizontal
multiple chain conveyor which is composed of a
plurality of parallel endless chains 36 driven in
unison by sprockets 38 mounted on a driving shaft 39
disposed at a delivery end of the aligning station
34. Driven ~;piral rolls (not shown) are mounted in
the endless chains 36 and are driven in synchronism
therewith. ~~ driven endless chain 40 engaged at
opposed ends thereof with sprockets 42 mounted on
vertical shafts is provided along one side of the
aligning station 34 to cooper<~te with the spiral
rolls (not shown) in aligning one end of the cants
along a common reference line=_ extending in the
feeding dire<:tion on the opposed side of the aligning
station 34. It is noted than according to the
illustrated ?mbodiment, the dri~,ren endless chain 40
forms and angle of about 6o degrees with the feeding
direction of the cants C.
From the aligning station 34, the
successive cants C are disch,~rged to a spacing
station 46 w:zich includes a series of three multiple
chain conveyors 48, 50 and 52 independently driven by
respective motors 54, 56 and 58 to move the cants C
transversally of their long:_tudinal axes. The
multiple ~~ha:Ln conveyors 48, 50 and 52 each comprise
a plurality of parallel endless ~~hains 60 disposed in
a latera:~ly spaced-apart relationship on a frame
structure 62. The spacing station 46 further includes
a sensing sy;~tem (not shown) which is coupled to the
control system (not shown) tc analyse the space
between the pants C. Accordingly, for two successive
cants, the control system computes the distance
existing between the cants C and consequently
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increases o:~ reduces the feeding speed of the
conveyor on which the upstream or second cant is
supported such as to provide a desired space between
the two. More generally, it can :~e said that based on
the sensing data, the control system creates a
differential of speed through the conveyors so as to
obtain a desired spacing between the cants C. It is
understood treat different number: of conveyors may be
provided .*~o obtain the intended result.
In l.he event that two cants C overlap, the
operator can reduce the spee~3 of the preceding
conveyor in order to create a rE~quired space for the
cant C ire e:ccess . Then, the operator may place the
excess cant behind the first cant. Therefore, this
permits to maintain a substantially uniform space
between tile cants .
It is also noted that since the movements
of the cants C is continuous, it is possible to
reduce t:ze average speed of the multiple chain
conveyors 48, 50 and 52 thereby facilitating the
transportatic>n of the cants C and the work of the
operator.
Moreover, another advantage of the present
invention re;~ides in the fact that the empty spaces
due to Loading problems occurred at the intake
station 12 a.nd to rejections o:- deficient cants by
the operator may be fill by adjusting the relative
speed of the multiple chain convE~yors 48, 50 and 52.
The cants C are then transferred one by one
from the spacing station 46 t:o a scanner infeed
station 6=t. "'he scanner infeed station 64 consists of
a feeding apparatus comprising a frame 65 on which a
plurality of parallel endless cr.ains are disposed in
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a laterally spaced-apart relationship. Referring now
more specifically to Fig. 3, it can be seen that the
endless chains are grouped in five sets of three
chains identified by reference numerals 66, 68, 70,
72 and 74 , the chains of a same set. being driven in
unison by a common motor. Accordingly, the sets of
chains 66, 68, 70, 72 and 74 are driven by respective
motors 76, 78, 80, 82 and 84. The motors 76, 78 80,
82 and 8~ a:re coupled to respective driving shafts
86, 88, 90, 92 and 94 extending transversally of the
longitudinal axis of the chains. The driving shafts
86, 88, 90, 92 and 94 are provided with respective
sets of three sprockets 96, 98, 1.00, 102 and 104
distributed along the length thereof such as to
engage the set of chains a;~sociated therewith.
The chairus are provided with attachments 106 for
engaging and moving the cants C forward. The cants C
are transported above the chains on a plurality of
longitudinal rails 108 extending along the sides of
the chains.
A :sensing system (not ~~hown) adapted to
detect the space between the cants C emanating from
the last multiple chain conveyer 52 of the spacing
station 45 c~~mmands, through the control system, the
successive activation of the set=s of chains 66, 68,
70, 72 and 74 to transport onE~ cant at a time in
front of the scanning station 14. Each set of chains
66, 68, 70, 72, 74 accumulates c_>ne cant. The sensing
system is further adapted to ascertain the width of
the incoming cants in order to control the relative
position of t:he attachments 106 of the sets of chains
66, 68, 70, 72 and 74. Accordingly, a uniform space
between adjacent cants accumulated on the upstream
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side of the scanning station 14 is provided. As the
set of chains 66, 68, 70, 72 and 74 are independently
driven, it is possible to vary the speed thereof
according to the number of cants waiting in front of
the scanning station 14. The scanner infeed station
64 also optimises the productivity of the wood edger
10 in that it increases the rate at which shorter
cants are fed. Indeed, it is advantageous to be able
to vary the advancing speed of the cants, as shorter
cants require less time to be processed.
Fig. 3 illustrates two successive cants C
and C' which are moved transversally of their
longitudinal axes toward the scanning station 14 by
the first set of chains 66 and the second set of
chains 68, respectively. The chains of the first set
66 are driven in unison to cooperate in transporting
the cant C by means of their attachments 106a.
Similarly, the chains of the second set 68 are driven
in unison to cooperate in transporting the cant C' by
means of the attachments 106b. The attachments 106 of
the first and second sets of chains 66 and 68 are
respectively engaged at three spaced-apart locations
on a longitudinally extending upstream surface of the
cants C and C' to push the same forward. The relative
speed of the first and second set of chains 66 and 68
is controlled so as to provide a uniform feeding
rate, as explained hereinbefore. Indeed, the cant C
and C' may be simultaneously supported on the scanner
infeed station 64, while not being advance at the
same speed.
It is understood that the number of sets of
chains and the quantity of chains per set may vary in
accordance to the length of the cants and the number
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of cants which it is desired tc accumulate in front
of the scanning station 14. It i.~ noted that the sets
of chains 66, 68, 70, 72 and 74 could be replaced by
corresponding sets of endless belts.
From the scanner infE=_ed station 64, the
cants C are t=ransferred onto a conveyor 110 extending
through the scanning station 14. The conveyor 110 is
composed of at least two laterally spaced-apart
parallel endless chains or belts driven in unison.
The speed o:E the conveyor 110 may be adjusted in
accordance with the desired number of cants to be
processed per minute.
The cants C carried by the conveyor 110
through the :canning station 14 ire optically scanned
to detect the profile thereof. As mentioned
hereinbefore, the data obtained during scanning are
processed bar the control sys~=em (not shown) to
establish tree orientation of the cants and the
position of the circular-saws (not shown) of the
edging station 18.
Once a cant has been scanned, it is
positioned onto the edger infeed table 16 by an edger
positioning apparatus 112. As :peen in Fig. 1, the
edger positioning apparatus 112 comprises three
modules 114 which are disposed i.:~ lengthwise parallel
laterally spaced relation to one another on a
downstream side of the scanning station 14. It is
noted that depending on the length of the cant
emanating from the scanning station 14, only the two
modules 114 that are nearest to the ends of the cant
may be operated by the control t>ystem (not shown) to
position the cant on the edger infeed table 16.
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Referring now more specifically to Fig. 4,
it can be seen that each module 114 includes first
and second side by side extending conveyors 116 and
118 which are driven by respective reversible motors
120 and 122. Each module 114 further includes a
supporting member 123 disposed between the first and
second conveyors 116 and 118 to fill the gap between
the delivery end of the conveyor 110 and the edger
infeed table 16. The first conveyor 116 includes an
endless belt 124 having three 126a, 126b and 126c
secured at regular intervals thereon. Similarly, the
second conveyor 118 includes an endless belt 128
having three cant engaging members 130a, 130b and
130c secured at regular intervals thereon. Each cant
engaging member 126, 130 has a front pushing side 132
and a rear abutment side 134.
In operation, as shown in Fig. 7a, a sensor
(not shown) disposed in the area of the delivery end
of the conveyor 110 and the receiving end of the
edger positioning apparatus 112 detects the presence
of a cant C and then sends a signal to the control
system (not shown) to activate the first conveyor 116
of at least two modules 114 such as to position the
front pushing side 132 of the cant engaging member
126a thereof adjacent on upstream longitudinal
surface of the cant C. The cant C is then pushed by
the cant engaging members 126a.
At this time, the second conveyor 118 of
each module 114 is not activated and thus the cant
engaging member 130a is immobile at a certain
distance downstream of the cant C. As the control
system (not shown) has already obtained and analysed
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the profile data of the cant C, it can control the
speed and the advancement of the second conveyors 118
such as to properly wedge the cant C between the
front pushing side 132 of the cant engaging member
126a of each operated first conveyor 116 and the rear
abutment side 134 of the cant engaging member 130a of
each operated second conveyor 118, aS 111ustrated in
Fig. 7b. It is noted that the wedging operation of
the cant C is effected while the first conveyors 116
are driven to move the cant C toward the cant
engaging member 130a of the second conveyors 118.
Once the cant C is properly held in
position between the cant engaging members 126a and
130a, the first and second conveyors 116 and 118 are
driven in unison to transversally transport the cant
onto the edger infeed table 16, as illustrated in
Fig. 7c. The alignment and the position of the cant C
with respect to the circular-saws (not shown) of the
edging station 18 are controlled by the control
system which positions the first and second conveyors
116 and 118 of the modules 114.
For the sequence illustrated in Figs. 7a to
7c, the cant engaging members 126a serve as pushing
members behind the cant C, whereas the cant engaging
members 130a serve as abutment members in front of
the cant C.
Once the cant C has been positioned on the
edger infeed table 16, the first conveyors 116 are
driven backward, while the second conveyors 118 are
driven forward, as illustrated in Fig. 7d. At this
stage, the cant engaging members 126a will serve as
abutment members for the next incoming cant C',
whereas the cant engaging members 130a will
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eventually return to the receiving end of the edger
positioning apparatus 112 to push an incoming cant.
The cant engaging member 130c of the second
conveyors 118 and the cant engaging member 126a of
the first conveyors 116 will then cooperate to move
the next incoming cant C' as per the way described
hereinbefore.
Accordingly, it can be said that the cant
engaging members 126 and 130 alternately serve to
push and retain the cants.
Figs. 5 and 6 illustrate in greater details
the construction of the cant engaging members 126 and
130. More particularly, each cant engaging member
126, 130 includes a base portion 136 and an upwardly
protruding portion 138 extending substantially at
right angle therefrom. A sleeve member 140 fitted
over the upwardly protruding member 138 is normally
urged in a forward position relative thereto by two
compression springs 142 extending from two vertically
spaced-apart horizontal bores 144 defined in a front
surface of the upwardly protruding portion 138.
This construction provides a front pushing
side 132 which is compressible to compensate for
inaccurate positioning of the cant engaging members
126 and 130 by the control system, while still having
a rigid rear abutment side 134 to retain the cant.
The first and second conveyors 116 and 118
are provided with lateral guides 146 which extend on
the sides of the belts 124 and 128 to laterally
restrain the motion of the cant engaging members 126
and 130. The lateral guides have an L-shaped
configuration and include a portion which extends
above the base portion 136 of the cant engaging
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members 126 and 130 to lim__t upward movements
thereof.
It is understood that ~~he number of modules
114 of the edger positioning apparatus 112 may be
different th,~n three and that i;he first and second
conveyors 11~ and 118 thereof rnay consist of chain
conveyors in:~tead of belt conveyers. Furthermore, the
number o:f cant engaging members ~~er conveyor could be
less or more than three.
As seen in Fig. 4 and 6, the edger infeed
table 16 includes a number ~~f retractable cant
supports 148 which are adapted to receive the cants
from the edger positioning apparatus 112. The
retractab:ie cant supports 148 are disposed near the
modules 114 of the edger positioning apparatus 112
and are rockable between raised ,end lowered positions
about axes which are parallel to the feeding
direction of the edger positioning apparatus 112. The
retractab:Le ~~ant supports 148 enable to temporarily
maintain the cant above a conveying surface 150 of
the edger infeed table 16.
The conveying surface 150 of the edger
infeed table 16 is composed of a number of driven
rollers 152 which are disposed between the modules
114 of the edger positioning apparatus 112 for
longitudinally accelerating the cants in a direction
transversal thereto.
As seen in Figs 2, the edger infeed table
16 further includes a series of overhead pressing
roller 154 which are adapted to engage an upper
surface of the cants C to guide the same into the
edging station 18.
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Referring now more specifically to Figs. 8
and 9, each overhead pressing roller includes first
and second frame members 156 and 158 which are
pivotally mounted on a common pivot 160. The first
frame member 156 supports at a first end thereof a
roller 1.62 which is adapted t;o roll on the top
surface of the cants.
A pair of pneumatic bladders 164 are
disposed between the first and second frame members
156 and 158 of each overhead pressing roller 154 to
act as a damping member in order to absorb vibrations
transmitted to the roller 162. The pressure inside
the bladders may vary to adjust the pressure of the
roller 162 on the cants C. The damping member could
also be other means, such as hydraulic and pneumatic
cylinders, s~>rings and resilient links.
As seen in Figs. 8a and 8b, each overhead
pressing roller 154 includes a p:zeumatic or hydraulic
cylinder 166 which is pivotall~r mounted to a main
frame structure 168 of the infeed table 16 to act on
the second frame member 158 su<;h as to selectively
raise and lower the roller 162 in an inoperative
position wherein the roller 162 is out of engagement
with the cant and an operative position wherein the
roller 162 engages a top surface of the cants.
The first and second frame members 156 and
158 are prozrided with cooperating abutment members
170 and 172 which are adapted to assist the cylinder
166 in maintaining and displacing the roller 162 in
the inope:rati.ve position thereof.
In operation, the cant is maintained above
the driven rollers 152 by t.:~e retractable cant
supports 148 to permit to the cant engaging members
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126 and .;30 to move away from the cant and to the
overhead pressing rollers 154 to reach their
operative position. Then, the retractable cant
supports 148 are pivoted to their lower position to
permit the engagement of the cant C by the driven
rollers 152.
they cant C is then longitudinally
translated t=hrough the edging station 18 where
circular-saw~~ (not-shown) tr_i.m the unfinished
longitudinal wane surfaces of the cant C.
The edged cant can then be transferred to a
discharge table 174 where it can be conveyed to an
appropriate ~~taring facilities.
It is noted that the present invention has
been described in the context of a sawmill, since the
transfer and orientation of a wood cant particularly
exemplifies the problems to which the present
invention is directed. However, it is understood that
the invention is applicable to workpieces other than
wood cants, ~~s for instance elongated steel elements
produced during rolling mill operations.
-20-
