Note: Descriptions are shown in the official language in which they were submitted.
73
1~60~
CLAMPI~:G D~VICE FO~ BELTS
SP EC I F I CAT ION
Pl~ld of the ~nvantlon
our pre6ent lnv~ntlon relatas to a belt cla~p ~nd,
more partlculnrly, to a clamplng devlce for clamplng a
convayor bolt wlth a prescrlbed force, o.g. ln as~ocl~tlon
wl~h a bslt press, wLth mechaniam~ or devices ~or a~tnbllshlng
or ad~ust~ng conveyor belt tsnslon, for briklng the motion of
a conveyor bfllt and for use for guldlng and tanslonlng
mech~nlsms of eny deslrQd type.
B~lt pr~sses whlch utlll~e clamplng devlces of the
typ~ descrlb~d hereln or whlch can utillze such clamplng
devlc~ are dlsclo3~d lnter alla ln the commonly as~lgnod U.S.
p~tont~ 4,398,991, 4,3aa,a60, 4,393,666, 4,~23,~74 ~nd
4,426,573. ~efersnc~ rnay also be had to the patent docurnents
of r~cord in tho fileY of thesQ pat~nts.
~ack~round oE tha Inventlo~n
It 13 known to provlde clamping devlce~ for the
aroredescrlbed purposes whlch can conslst of an upp~r crossbax
or tr~vcrse, ~ lowor cro~bar or trav~r~ and tenslonlng bolts
connectsd to thes~ two traverses, i.e. so-called dr~wboltn.
Tha upper ~nd low~r traverses have surfac~s whlch are adnpted
1460~ t73
to eng~ga dlrectly the upper and lower 3urface~ of the
conveyor belt. A support can be proYlded for the entlre
assambly. The drawbolts can ba tightanod by a torque wrench
to preacrlbed torque ~ettlngs and hydraullc ~ctu~tors c~n be
provlded for them lf deslred.
Since tha drawbolts elank the belt and act 3t the
end~ o~ the tr~verses, the la~ter are sub~ect~d to a more or
lec3 arcuate elA~tlc deformatlon ~o that the cl~mplng force
and hance the belt-holdlng force i3 not unlformly dlstrlbuted
over th~ entlro l~ngth~ o~ the crossbars.
The edge~ of the conveyor balt may be clamped ~ore
strongly or tlghtly than central reglona of the conveyor belt
and frequently the edge reglon~ c~n sho~ dam~ge rssultlng from
excosslva local clamping 'orce. The mountlng for the D se~bly
lS 18 ~tt~ched dlrectly to the croaabar~ or to one of them. As a
r~sult, the cro~sbars mAy be sub~ected to a co~plex stres~
p~ttern which can lmpair the ~tabllity of the clamplnq device
when hlgh ten3ile forces are applled to the conveyor bele,
Should the system bre~k down, there 1~ dAnger to perAonnel as
~ell aa to tha product being clamped.
ob~ecta o~ the Inventlon
It lc the prlnclpal ob~ect of the preeent lnventlon
to provlde a clamping devlce for the purpose~ and of the type
~nscrlbed wheeeby the belt-holdlng ~orce can ba more unifor~ly
dl~trlbuted over the wldth of the clamped conveyor belt and
whereby the aforementioned dangers or dls~dvantages of
~ 1~60& ~ 73
~t~blllty pheno~ena and unpredlctable stres6 p~tterns no
lonq~ ~rl~e.
~ nothar ob~ect of the lnventlon 19 to provlde an
lmprov~d clamplng devlce ln whlch, notwlth~tandlng th~ ~ct
S that the drawbolts act at the ends Oe the croa~bars or
traverso~, a hlghly unlform clamplng-force dl~trlbutlon 19
~chleY~d ov~r the wldth of the belt.
Yot another ob~ect of thL~ lnvention 1~ to provlde a
conv~yor-belt clamp ~hich obvlates the dlsadvAntages of the
prlor ~rt and can provide Lmproved cl~mplng condLtiona for the
conv~yor b~lt.
Summlry of the Inventlon
The~e ob~ects ~nd other3 ~hich wlll become app~rent
herelnater are ~ttalned, in accordance wlth the lnventlon, ln
lS a balt prQas havlng traverses or crossbars of the type
d~scrlbod and drawboltA interconnectlng the~e cro3sbarA at the
ends thereof to opposlte ~ldes of ~ conveyor b~lt clamped
betwêen the cro~sbars, whereln the clamp al80 COlltprl8a~ A palr
o~ clamplng bars each lnterpoaed between a reApectivQ one o~
the cro3~rs and a re6pect~ve 6urace of tha belt, the
c1amplng bars belng formed ~t thelr ends wlth holes traversed
wLth clear~ncQ by the drawbolt~, at least one of thssa
alamping bara belng b~acad relatlva to the respectlve
crosffbaes by hydr~ullc pressurlzlng or braclng mean3 affactlng
~ unl~orm force dlAtrlbutlon acroAs the wldth of the belt, the
mountlng being connscted to one of thess cldmplng bars 80 tbat
the l~ttar ls held or guided on the support dlrectly.
~Z22 ~73
1460~
The hydraullc braclng mflans cnn thus sat up or
tr~n~mlt the clamping force.
The hydraullc braclng meane c~n lnclude ~ number of
hydroullc pl~ton-~nd-cyllnder unlt~ dlsposed ln sUcc2aslon
acros~ th~ wldth o~ th~ belt between the sespectlve clamplng
bers and the ~soclnted crossbar, or an e~pandable member
axtendlng the full wldth of the belt between the cl~mplng bar
And the respectlve force bar and exp~ndable by hydraullc fluld
pressUre In elther caqe, the hydrlullc fluld pressure c~n be
~upplled by ~ pump.
In order to mlnlml2e the welght of the clamplng
devlce when hlgh ~orce6 are lnvolved, the cro3sbars are formed
as box sectlon~, l.e box profiles of rectangulflr cro~
~ectlon, whlle the clamplng bars are formed as channels whlch
can be open ln the directlon o the respectlve cro~sbars to
receiYe the hydraullc braclng means.
~ he belt-holdlng forces sQcurlng a clalnpQd conveyor
belt c~n be Aeparated on the one hand cle~nly from the guldlng
~orcss or the clamplng bars on the other hand by m~lntalnlng
the aforementloned cle~r~nce betweeen the walls of the hol~s
ln the clamplng bars and the drawbolts.
~ one of the cla~plng bars 19 then flxed to the
support, the stresses wlth which the conveyor belt 18 clamped
can b~ su~talnad by the cro~sbnrs wlthout any o~ the problem~
encountere~ heretofore nnd 31gnlflcAnt cl~mplng Corces c~n be
gan~r~ted wlthout conce~n that deformatlon~ ln the clamplng
bar~ created by the belt-holdlng forces wlll be tran~mltted to
th~ crossbars or the hydr~ullc unlt.
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.
'73
14608
~ ha form of the hydraullc unlt can be, ln prlnclple,
optlonal a~ long as the hydraullc unlt i9 able to braca
b~twaen the clamplng bar and the crossbar and to dlstrlbute
the eorces unlformly over the length of th0 cl~mplng bar and
h~nc~ thq wldth of the conveyor belt. Aq not~d, lt ~y
conul3t of a coll~ctlon o~ plston-and-cyllnder unles 3pacsd
ovar the langth of the a~socl~ted cro~sbAr and elther
connected to a pump or adapted to be pre3~ùrl2ed by tlghtenlng
the drawbolt. In the l~tter c~e, a val~e may clo~e off the
hydr~ullc llnes connecte~ to the cylinders rom the pump. In
thl~ a~se, moreover, the pl6ton-and-cylindar units of each
cro~cbar ~re combined in a clo~ed hydraulic system.
Pr~er~bly the hydraulic unlt compris~s hosai, whlch ara
delormabl~ ln crosd ~ection, and a de~lectlon compensator.
~he hydraulLc hoses can be connected to a pump. Arrangements
u~lng hydraullc hosQ~, bendlng ch~r~cterlAtlc or deflectlon
compcnsAtors and the llke are kno~n from German p~tent
document3 DE-OS 30 2a 400 and DE-OS 30 28 401 and ariti3h
applicatlon GB 2 0~2 966. They can be u3ed ln con~unctlon
wlth tho lnatant lnventlon l~ well.
There aro numerous advantages to tha lmproved system
of thu lnventlon many of whlch wlll b~come ~pparent wlthout
dl~cu00ion, but others o~ whlch ~re outllned here. Por
sxnmple, th~ belt-holdlng force 18 cleanly ~eparated from the
cl~plng ~orce~ ~pplle~ through the bydraullc unlt. The clear
s0paratlon of ~uch forcea ~llminates ~n lnterpl~y whlch may
ra~ult ln com~lex ~tre~sQ~. Deformatlon~ of the clamplng bAr
1460B
~Z ~'73
or bar~ ~nder belt-holdlng forcss ara not tran~mltted to the
hydraulic unlt or the a~sociated crossbars. The loadlng and
~tr~sing condltlons are thus more predlctabl~ and
dlsAdv~ntageous three-dlmen~lonal-stres3 dlserlbutor3 are
elimln~t~d. ~he clamplng device can b~ made p1rtlcularly
ll~ht ln ~7elght whlle belng functlonally reliabl~.
Brlef De~crlptlon o~ the Draw~ q
The abov~ ana other ob~ect~, eeatures and advantages
of the present lnventlon wlll become more readlly apparent
fro~ the followlng descrlptlon, reference belng mado to the
aecomp~nying d~a~,71ng in whieh:
FIG. 1 ls a perspectlve vlew of a clamplng devlce ln
accord~nce wlth the lnventlon dlagrammatlcally showlng
convtyor belt ln place7
FIG. 2 1B 1 diagrammatlc cro3~-sectional vlew, drawn
to a lasger ~cale than F~G. l and lllustratlng one type cf
hydr~ulle unit; and
FIG. 3 la a vlew simllar to FIG. 2 but showlng only
the upper clamplng bar in cro~s section to reveal A di~erent
hydrAullc braclng acr~ngement.
8eeclfic Descrlptlon
The clamplng devlce 1 shown ln FIGS. l and 2 of the
drAwlng ~nd to the extent that lt eontalns 31milarly
funetionlng struetural element3 with the same reference
numer~l~, the clAmplng devlce lOl of FIG. 3, are lntended Eor
1460B ~ 73
the cla,mplng of conveyor belts 2 ~nd 102 wlth pr0scrlbed
cl~mplng forcea. The clamplng devices can be u~ed ln or in
~socl~tlon wlth belt-conta1nlng or traction-braklng, guldlng
and ad~u~tlng m~chanism~. The ba~lc constructlon of the
clamp~ng devlce la ~n up~er cros~bar 3, 103, a lower Gros~bdr
g, 104, dr~Wbolts 5, 105 lnterconnectlng the snda o~ the
crossbare 103 and 104, and a mountlng 6 whlch enable~ the
aa~mbly of cros3bars and the entlre clamplng davlce to be
supported ln the ~ppar~tua. The clamped conveyor b~lt 2, 102
10 19 Almilnrly held by this mountlng 9, e.g. to allow l ten~lle
stress to b~ ~pplied to the belt.
~ h~ crossbara 3, 103 and 4, 104 are provided with
r~p~ctlYa clamplng bars 7, 107 and 8, 108 whlch dlrectly
~ngagc the upper ~nd lowet surflces of the b~lt 2, 102~
~he cros~bars each have holes 9 throuqh whlch ths
bolts S, lOS pa59 with clearance.
Vital to the lnventlon 18 the fact th~t flach cl~mplng
b~r 7, 107 18 brac~d agalnst the respectlve cro~bar 3, 103 by
a re~p~ctlve hydr~ullc unlt lO, llO whlch ssts up or transmlts
23 the cl~mplng force.
FIG. l shows that the mountlng 6, a bracket ll whlch
gulde~ the clamplng bars 7 and~or 8 ~nd ~lternatlvely tho
clamplng bars 7 ana a can be effected wlth lugs ~or ad~u~tment
for ~nchorlng cables 13 extendlng to the le~t as Ahown ln
dot-d~h llnes ln FIG. l and serving ~e the anchorlng monns
whlch allows freedom of vertlcal movemsnt between the clamplng
bar~ 7 and 8 and positions them in the apparatu~ ln the
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1~60Y
hori~ontal dlrectlon. slmllar means are provlded for the
clamplnq b~r~ 107 and 108 of PIG. 3.
Th~ meana for affixlng the clamplng bars eo tha
m2untlng ar0 arr~ng~d so that deformatlons o ~lth~r clamping
bar 7 or a (or 107, 103) are not tr~nsmltt6c disadvantdqeou31y
to th~ Assoclated cro~sb~r 3, 4 or 103, 104 and the
co:re~pondlng hydraulic unlt 10, llO.
~hls Insures that the belt-holdlng forc~s on the one
hand and tha clA~plng force~ 3e~ up by the hydraullc unlt on
the othar are ~epa~ated from one another and thu~ ellmlnlte3
compl~ ~treas patterns on the clamp.
The cro~bars 3, 4 and 103, 104 are formed by
horlzontally stacked box-aectlon steel membsr3 ~hlle the
clamplng bars 7, 8 and 10~, lOa lre formed ~a upwardly open
chann~l sectlon~.
In the embodlment Oe PIGS. 1 and 2 hydrau1ic unlt 10
comprlae~ hydraulic hoses 14 o deformable cross sectlon whlch
lle ag~ln~t a deflectlon compensator 15 and cAn be expAnded by
hydr~ullc pre~sure supplled by u pump 16 vla a valve 17.
The latter Yystem can bo almllar to that described in
~rmAn patent docum~nt ~-OS 30 2a 401.
In FIG. 3, howevcr, 1 multlpllcity of
plston-and-cyllnder unlts 114 c~n be provlded and can be
braced vla swlvel ~hoes 115 agalnst the clamplng bar 107. Thq
pump .116 supplles hydraullc fluld to the~e cyllndor~ vla the
V~lve 117 and a presqure accumulator 116 c~n b~ connected ln
thi~ clrcult in the embodlments of both PIGS. 2 ~nd 3, the
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1~60~ 2 ~'73
valve 17 or 117 ~an be clos~d and the pump deenergized to
block ~ro~ the hyd~aullc llnes and allow the hydrlulic ~orc~
to ~ g~ner~tnd by tlghtenlns the d~awboltY 5 and ~05.
