Note: Descriptions are shown in the official language in which they were submitted.
CA 02234274 1998-04-08
APPARATU5 FOR MOVING ~ BE~T, IN PARTICULAR FOR MO~I~G A
CONVEYOR BELT, IN A SYSTEM FOR DEWATERI~G A WEB OF MATERIAL
~ Background of the Invention:
Field of the In~ention:
The in~ention pertains to an apparatus ~or moving a belt, in
particul~r an apparatus for moving a con~eyor bel~ in ~ system
for dewaterin~ a web of ma~erial, such ~s a belt or a felt
belt; the ~ppara~us has a plurality of support rollers and
deflection rollers, ~y way of which the endless belt can be
moved to revolve, a device for adjusting at least one of the
deflection rollers in the travel direction of the belt,
15 whereby the tension of the belt can ~e set, and a device for
controlling the dlrection of motion of the belt.
In rç3lated prlor art ~pparat~lses, at least one of the
deflection rollers is supported so that lt can be a~justed an~
flxed in the longitudinal direction of the belt. By adjusting
~h~ deflection rolle~, the belt can be tensed in ~ccordance
with the specific technical requirements.
In tho~e prior art ~ppar~tu~e~, at least ~n~ o~ th~ support
25 rollers for the belt, disposed between the deflection rollers,
is also adjust~ble in its position relatit~e to the direction
o~ motion o~ tlle belt. Thls i:3 dor~e by ~etting (~nd flxing in
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the ~3et pos ~ tion) one of the t~o bearings of the support
roller in the diret;:tion of motion of the belt. As a result,
the orientation of the rotary shaft of that support roller
relative to the dir~ction of motion of the belt is varlable.
5 Due to the ~act that the belt line of contact between the belt
and the support roller is parallel to the shaft o~ the support
roller, and the ~elt is oriented perpendicul~r to the shaft of
the suppor~ roller, the direction of motion of the 3~elt can be
regulated by this p~ovision. As a result, guidahce of the
10 belt is a~sured ov~r all the ~upport ~ollers and deflection
rollers in a way tha~ meets th~ specific t~chnical
requireme~ts.
Summary of the Inven~ion:
lS It is a~cordin~ly an ob~ect of the invention to provide an
apparatus for moving a belt, in particular a con~eyor belt in
a sys~em for ~ryi~g a material web, which improved relative to
~he pri or art ~evices ~nd methods of this general type and
which i~ structu~ally ~ nplified without thereby impairing its
~0 operability .
The basic premise o~ the invention is the recognition that the
direction of motion of the belt is controllable not only ~y
means o~ the angular po;~ition of the suppor~ rollers but also
25 by the an~ular position of the de~lection rollers.
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.,~.,
With the ~oregoing and other objects in view there i~
provided, in accordance with the invention, an apparatus fo~
moving an endless ~elt, compr~si~g:
a plurality of rotatably s~pported support rollers and
deflec~on rollers;
an endless belt, such as a screen belt or ~elt belt, traveling
o~ the support rollers and about the deflection rollexs along
a longitudinal direction;
t~o ~earings rota~ably supporting the one deflection ro~ler
0 and being movably suppor~ed in the longitudinal direction of
the belt; and
a control device connected to the bearings for ~ndependently
shifting the bearings in the longit~di~al d~rection of the
belt and ~or adju~ting the one deflection rc~ller and sett~ ng a
5 tension of the belt and co~trollin~ a direction of motion of
the belt.
In othèr words, t~e objects of the invention ~re satisfied in
that each bearing o~ the deflection roller is ~djustable in
2Q the longitudinal direction of the ~elt, and each is assigned
its o~n control device, by which 'che ~wo bearings of the
deflection roller are adjustable to different extents or in
different directions. The direction of motion of the belt is
thus controllable by means of ~he deflection roller.
2S
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In accordance with an added feature ~f the inventlon, the
control device comprises two separate control de~ices each
operatively associated with a respecti~e one o~ the bearings,
and the separate control deyicas adj usting the beari~gs to
~ ~ m~tually different extents and in ~utually different
directions.
In accordance with an additional feature of the inven~ion, two
adjusting spindle~ are respectively connected to the two
bearings of ~he deflection roller, ~hereby a rotati~n of t~e
spindle ca~ses a shift of the respective be~ring ~ n the
longitudinal direction.
I~ accordance with another feature of the invention, a ~e~el
15. gear connects each o~ the adjusting spindles to a power ou~put
shaft for rotating the spindles~
In accordance with again an added feature of the invention,ian
electric m~tor is ~onnected to each of the adjusting spindles
~0 for rotating the adjusting spindles, ~nd a control circuit is
co~nec~ed to and selecti~ely drives the electric motors at
mutually differen~ speeds and in m~tually different
directions.
Xn accordance with again an additional feature of the
invention, an electric motor and a drive shaft connect to the
tw~ ~dj~sting spindles vi~ a respective power takeoff, and ~
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control gear (e.g. superposition gear) i~ dlspose~ between th~
power ta~eo~fs of the adjusti~g spindles.
In accordance with agai~ another feat~re of the invention,
- s there are provi~ed hydra~lic control devices connected to the
two bearings for selectively and independently adjRsting the
bearings.
In accordance with again a further feature of the invention,
the control dev~ce comprises two toothed belt drives each
connected to a respective bearing, and an electric motor
driving the toothed belt drives~
In accordance wit~ yet another feature of the inv~ntion, two
independent electric motors are provided each driving a
respective one of the toothed belt drives.
In accordance ~ith a con~omitant featu~e o~ the invention, the
elec~ric motor is a single electric motor drivin~ the two belt
drives, and including a drive shaf~ connected to the toothed
~elt ~rives ~t respective power takeo~s, and a control gear
(superposition gear) i~ disposed between the po~er ta~eoffs of
the two toothed belt drives.
25 Other f eatures whi~h are considered as chara~eristic for the
inven~ion are ~et forth in the appended ~laims.
~ CA 02234274 1998-04-08
.
Although the in~entlon is illustrated and described hereln as
embodied in an apparatus for ~oving a belt, in particu~ar for
moving a co~veyor ~elt, in a system for dewateri~g a web of
material, it is nevertheles~ ~ot intended to be limited to the
details shown, since various modifications and structural
~ changes may be made therein witho~t departing from ~he spirit
of ~he invention and within the scope and range of equivzlents
o~ the claims.
The ~on~truction and method of operation of the invention,
however, together with additional objects and advantages
thereof will be best understood from the following description
of specific embodiments when read in connection with the
accompanying dra~ings.
~rief Description of the ~rawings:
Fig. 1 is a partly bro'~erl away, partial pl2n view of ~ left-
hand Qnd of ~ first embodiment of the invention;
Fig. la is a partly ~roken away, partial side elevational view
thereo~;
Fig. 2 is a p~rtly broken away, partial plan vlew of a left-
hand end of ~ sccond embodin~ent of tho invention;
Fig. 2a is ~ partly ~roken a~ay, par~ial side e' evational view
thereo~,
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Fig. 3 is a diagrammatic and partial plan ~iew o~ a left-hand
end of a third embodiment of the invention;
Fi~. 3a is a partly broken ~way, partial side elevational view
~ thereof;
Fig. 4 is partial plan vie~ of a left-hand en~ of ~ rourth
embodiment of the invention; and
Fig. 4a is a partly broken away, partial side elevational view
thereof
Description of the Preferred Embodimen~:
1~ Referring now to the figures of the ~rawing in detail and
first, particularly, to Figs. l and la thereof, there is seen
a portion of an apparatus in a ~ystem for dewatering a web of
material, such as a web of paper, with a deflectio~ rollex l
on its left~hand end, over whioh a screen belt 2 is ~ulded
that wraps around the deflection roller 1 o~er approximately
180~. The belt 2 is ~uided over a plurality o~ support rollers
10 as its upper run moves a~ong the direction of ~otion A.
second de~l~ction roller is located on the right-hand end o~
the screen belt apparatus aro~nc~ which th~ soreen belt 2 also
wraps o~er an angle of about 180~. Sin~e such a screen belt
apparatus is known from the prior art, for ins~ance in a
system for paper production, ~he suppor~ rollers lo are only
- CA 02234274 1998-04-08
schemat~cally indicated in phantom and ~ne rlght-hand
deflection roller is not ~hown in the drawing~
One guide device 3 and 4 each for respecti~e be~ring blocks 31
S and 41 is located on the t~o sides o~ the screen belt 2. The
two ends 13 and 1~ of ~he rotary shaft 11 of the deflection
roller 1 are supported in the bearing bloc~s 31 and 41,
respectively. The bearing bloc~s 31 and 41 a~e formed with
bores 32 and 42, through which g~ide rods 33 and 43 pass. The
guide rods 33 and 43 are aligned in the longitudihal direction
of ~he screen belt apparatus. The two bearing blocks 31 and
41 are also zssigned two contro~ devices 5 and ~, by means of
which t~e bearing blocks ~1 and 41 are adjustable in di~ferent
directions and to differer~t extents in the direc~ion of motion
15 of the scrçen belt ~.
In Flg. la, a ~irst position of the bearing block 31 is shown
ln solid lines, ancl two other positions of the bearing block
31 are shown in dashed lines.
~0
The s~reen belt 2 is tensed to suit the technical requiremen~s
by displacing the two bearing blocks 31 and 41 in the
direction of motion A o~ the upper rlln of the sc~een ~elt 2 or
counter to the direction of motion A. In ~his case ~tensin~
of the belt), t~e two blocks 31 and ~1 are moved to t~e sa~e
extent, If, on the other hand, the two bea~ing blocks 31 and
41 are shifted in ~ifferent directions and to different
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extents, a c~ange in the angular orientation of the de~lection
roller 1 i3 brought about, whereby a control of the direction
of motion o~ the screen belt 2 i~ also effe~ted ~y the
deflection rollex 1.
- In the exemplary embodiment of Fig. 1 and la, the control
devices 5 and ~ assigned to the two bearing blocks 31 and 41
comprise an electric motor Sl and a ~ear 52. An adjusting
spindle ~5 is slaved to the power ta~eoff sh~ft 53 of the gea~
a 52 via a bevel gear 54. The adjusting spindle 55 p~sses
through a nut thread 34 located in the bearing block 31. The
power ta~eoff shaft 53 is al~o guided on a superposition gear
62, which is controlled by a seco~d electric motor ~1. The
power takeoff shaft 63 of the supe~position gear 62 i~ ~oupled
lS via a second bevel gear 64 to a second adjusting spindle 6St
which passes through a nut thread 44 dispose~ in the bearing
block 41. By rotation o~ the adjusting spindle 65, the
bearing block 41 is di~placea~le i~ the dire~tion parallel ~o
the ~creen belt 2.
The mode of operation of ~hi~ appa~atus is as follow~:
~hen ~he power takeoff shaft 63 of the gea~ 52 is rotated by
means of the ele~tric motor 51, ~hen via the adjus~ing spindle
2~ S5 the bearing block 31 is displaced along the guide rod 33.
The shaft 63 is also driven ~ia the ~uperpositio~ ge~r 62 by
the power takeoff shaft 53 of the gear 52, and wit~ that ~ aft
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the adjusting gpindle 65 assigned to the be~ring block 41 is
rot~ted via the bevel gear 64. As a re~ult, the ~earing block
41 is ~lso displaced along the guide rod 43.
If there is no change in the rotational spee~s of the power
~akeoff shafts S3 and 63 because of the superposition gear 62,
then the adjusting spindles 55 and 65 are rotated a~ the ~ame
speed, and as a result the t~o bearing blocks 31 and 41 ~re
displaced to the same extent~ The result is therefore solely
0 a tensing of the screen belt 2. Conversely, if the
superposi~lon gear 62 is controlled by means of the second
electric ~otor 61 in such a way that the power takeoff sha~
63 is rotated at a dif~erent ~peed from the power takeoff
~haf~ 53, then the ~djusting spin~les S5 and ~5 are rotated at
different speeds and as a result the two bearing block~ 31 and
41 are displaced to dif~erent extents. This changes the
angular orientation of the deflection roller 1, and as ~
resuLt the direction of motion of the belt 2 is controlled.
20 By ~uitable control of the two electric motors 51 and 61, it
ls thus po~3ible to effec~ either a tensing of the screen belt
2 or a change in the angular orientation of th~ deflection
roller 1 in order to control the direction of motion of the
screen belt, or to attain ~oth a tensing of the screen bel~ 2
and a change in the angula~ position of the deflection roller
1 in or~er to regulate the dlrection o~ motion of the screen
belt 2.
--10--
CA oi234274 1998-04-08
The exemplary embodiment of ~igs. 2 and ~a differs from the
exe~pl~ry embodiment ~f Figs. 1 and la only in th~t gear
wheels 55 and 66 are located on the power t~keoff shafts 53
S and ~3, and toot~ed belts 57 and 67 coupled to the bearing
~ blocks 31 and 41 are placed on the ge~r wheels. On their end,
the toothed belts 57 and 67 are placed ovex deflectio~ wheels
35 and 45.
1~ It is immediately eviden~ from the figures that a rotation of
the gear wheels 55 ~nd 66 causes the toothed bel~s 57 and 67
to move and, as a resu~t, the bearing blocks 31 and 41 are
displaced along the gui~e rods 33 and 43.
The exemplary embodiment of Figs. 3 and 3a differs f~om the
exe~plary em~odiment of Figs. 1 and la in that a hydraulic
control device 1 is provided to adjust the two ~eari~g block~
31 and 41. The control device 7 includes two adjusting
cylinders 71 and 73, assigned to ~he two bearing blocks 31 and
41, respecti~ely. The cylinders are acted upon with a
pressure medium from a pump 75 vi~ control sli~es 76, 77, 78,
79. Various adjustmen~s of ~he slidln~ valves result in the
pistons 72 and 74, ~nd thus the bearing blocks 31 ~nd 41, ~o
be adjus~ed. A central control unit 70 controls the pump 7
and the control slides 76-79.
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The bearing blocks 31 and ~1 can thereby be dlsplaced to the
sa~e extent or to different extents and i~ ~ifferent
directions. The screen belt 2 is thus selectively tensed
and/or its direction of motion is adjusted.
s
~ The exemplary embodiment of Figs. 4 and 4a differ~ from the
exemplary embodiment of Figs. 1 and la in that each of the
adjusting spindles 55 and 65 is assigned a respective ele~tric
motor 81 and 82. The two electric motors 81 and 82 are
controlled by a co~trol unit 80 in such a way that the
direction and speed of rot~tion of the adjusting spindles 55
and 6~ are arbitrary. The bearing blocks 31 ~nd 41 may thus
be displaced in the same or opposite directions, and to the
same or a different extent. In other ~ords, the screen belt 2
may be tensed and/or the direction of mQtion of the belt 2 may
be varied electronicallyJelec~rically.
lt is essential in ~1 the exemplary embodiments that the two
bearing ~locks of at least o~e def~ection roller of the syste~
are displaceable independently of one another ~oth to
di~fexent extents and ~ n different directions By adjusting
the deflection roller the screen belt may be both tensed and
controlled in its direction of motion. Since no devices are
thus nee~ed for ad~usting suppor~ rollers, a definitive
simplification o~ the screen belt apparatus is achieved
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:
While the embodi~ents described abo~e re~er to the best ~ode
embodi~ent with a screen belt, the invention is equ~lly
applicable to felt belts.
The a~ove-described de~ice for regulating a belt can also be
- contemplated in other apparatuses, in which an endless belt is
guided via deflection rollers and support rollers.
