Note: Descriptions are shown in the official language in which they were submitted.
7$~
Translation
P~T/DE 92/00301
DE~ICB POR ~Ea~G A CONTAI~ER
'
The invention relates to a device for h~at m g a
container, in particulax for heating a laborator~
container, with a molde~ body having a recess for
xeceiving the container, and an electric heating el~ment .
preferably constructed ~s a tubular heater and . ..
substantially adapted ~o the shape of the container, the
, heating ele~ent being arranged in the recess, preferably
:. in t~piral shape. :
Device3 of the kind in ~uestion ~ave been known
from practice for years. ~uch devices are described, .
among other things, as heating hoods. In the~e heatinq
hoods, the tubular hea~ing element~ are n~rmally ~pi~ally
, bent and embedded in a knit or ~abric of fiber glas~ yarn
i, or ~iber glas~ ~ilamont~. To ensure that the tu~ular
heating element maintains a shape adapted to the
i~ laboratory container to be hea~ed, the ~iber glass yarn i6
woven, knitted, braided, or crocheted around the t~bular
h~ating element in a tight and closel~ ~itting manner.
Finally, the tubular heating element rest~ on a molded ..
body which forms an insulating aa~ing or a support.
Fur~he~ k~own a~e devi¢es~ in ~hich the molded
or ~upporting body is mad~ o~ pressed ~ne~al or ceramic
fiber mat~rial. To prevent moisture ~rem pen-trating ~nto
I the materlal, the latter $~ impr~nated, ~or example, with
an epoxy ro~n~ The ~old-d body o~ thi~ known deviae is
pro~id~d with a rece~ adapt~d to tho laboratory container
to ~e heated, the surface of the recesfi being i~ aontact
with a heating element. The heating QlomQnt may likewis~
be embedded ln the sur~ace of the recess of the molded
body.
i! . ,
': :
2 ~
Z ..
Howe~er, the a~oresaid devices as known from
practice are proble~a~ic in practiae, ln~s~uoh a~ the
heating ele~ent is c08~1y to ~anufacture a~ a result o~
the necessary netting or the like, and cannot easily be
exchanged, in par~icula~ when the heating elements are
e~bedded. Con~equently~ when a heating element
malfunctions, it will be nece~sary to exc~an~e the entire
device or at least the heating element including its
complete netting.
~ t is therefore the object of t~e pxesent
invention to configure and fu~ther develop the devi~e of
the initially described kind such ~ha~ it ensures the
exahangeability of the heating element, wh~le being
reliably in~talled based on a ~imple construction.
The de~ice of the pre~ent invention for heating
a container, in particular a laboratory ~ontainer,
accompli~hes the above ob~ect with the characteri~tic
features of claim 1. Accordingly, in the initially
described device, the heating elæment i8 attaahed with its
end ~orming the opening for the container to a retainer or
holding ring. The retainer ring has at least a slightly
la~ger diameter than the rece~s o~ the molded ~o~
Furthermore, a~ a result of lo~alizing the retainer ring
on the upper edge region of the molded body, the heatin~
element extends into the reces~ suoh that, as it heats up,
it i~ able to expand adeguately toward the wall and bottom
o~ the molded body.
In acaordanoe ~ith th~ invention it ha#
lni~ially b~en r~cogniz~d that ths heating ~men~ cah be
install~d in the de~ic~ for an ex~hang~ With simp~e
te~hnical mean~, ln that the heating element i8 ~eaured
with its end forming the opening ~or ths cont~iner to a
retainer ring. This xetainer ring ~erves to ~eaure ~hs
hGating e~ament at the upper edge of the molded ~ody, it
being neces~ary that the retainer ring have at least a
$ ~ ~
~lightly larger dia~eter than the recess o~ the ~olded
body. Furthermore~ it ha~ b~en ~e~ogni~ed that the
arrangement of a retainer ring or the mounting of the
hea~ element by means of the retainer ring i~ al~o of
advantage ~ith respect to the thermal expansion of the
heating element occurring during the heatihg, when ~ a
result of localizing the ~etainer ring ~n the upper edge
region of the molded body, i.e., a~ter its install~tion,
the ~eating ele~ent extends into the rece~ ~uch that, as
it heat~ up, it is allowed to expand adequately toward ~he
wal~ and ~ot~m of the molded body. In other words, in
the ~unheated" condition of the device, it is necessary to
~pace the heating element from the uall and the lower
bottom of ~he molded body such that no compressive
stres~es cau~ed by the ~olded ~ody occur at maximal
thermal expansion.
. The exchangeability of the heating element, in
particular ~rom the viewpoints of economy and costs, i~
~urther favored, in ~ha~ the heating element itself is not
provided with a c05tly netting ~or the protection or
po~itioninq o~' the containe~ to ~e heated. However, in
. order to provide the re~eptacle or laboratory container
.3 which normally consists of gl~ss, to a aertain degree with
l a fir~ support within the tubular heating element, and
i moreover to prote~t it against damage resulting from the
hard sur~ace o~ the heating elewen~, advantageousl~ the
latter i~ loosely covered with a cloth which overliQ~ the
: upper edge region ~ the molded body, and i~ simple to
~emove wh~n the h~atlng elem~nt i~ en out.
, Furthexmore, the molted body is surround~d by R ca~ing
whlch extends ~ith lts rim at lea~t ln part over the upper
edge region, thereby clamping the cloth, in the a6sembled
condition, between the upper edge ~eglon o~ the molded
'. body and/or the retainer ring and the ca6ing rim. This
mea~Ure has accomplished that the heating element is
;l ~
;' :
2~7.~0
4 :
cus~ioned to a certain degxee relative to the container to
~e warmed or heated, and that, contraxy to the previously
customary ne~ting or the ll~e, this cushioning can ~e
e~ortle~s removed, when exc~anging the heating element or
for purposes o~ replacing a soiled cloth. :.
Arranged in further advantageous manner in the
region between the casing ~i~ and the upper edge region
of the molded body or the cloth aovering same is a seal or
pacXing, on the one hand for purpose~ of securing the ~;
aloth in force-locking engage~ent, and on the other han~ :
for preventing ~luid from penetrating from, ~or example, a
bursted container between the aasing and the molded body.
Thie paoking ~eals the region ~etween ~he ca~ing rim and
the edge region of the molded body as adequately as i~
~u~t possible with a f~bric or cloth extending
therebe~ween.
In a fu~her advantageous manner, the seal is
provided as a gasket which co~nprise~ a thicker inner ring
portlon and a thinner oU~er ring portion. In its
in~tallQd oondition, the thinner outer ring portion i~
~ranged on the edge ~egion or the cloth below the casing
rim, and the thicker ihner ring portion on the edge ~egion
or cloth outside the casing rim, i.e. toward the recess.
This con8tru~tional measure ~urther ~avors the sealing
bQtween the casing and the molded body.
With ~espect to the material, the cloth covering
the ~eating element consistB o~ a temperature-resistant
material, pre~era~ly a gla8~ ~abric. The previou81y
mentioned ~eal ~r packing is m~de o~ XUbb~, in particul~r : :
siliaon. ~h~ casing should nd~ahtageou~ly cons~ st o~ a
pre~o~ably acid-resistat~t pla~tic.
With respect to the con~tru~tional configuration
o~ the ca~ing it i~ of fur~her advantage, ~hen the ca~ing
con6i~t~ on the one hand of an upper portion ana on the
oth~r hahd o~ a lower portion detachable ~rom the upper
portion of the casing. In the assembled condition of the
device, the upper portiQn o~ the ca~in~ is slipped ~rom
the top onto the mold~d body, ~o that likewise in the
asse~led condition the lower portion o~ ~he ca~ng is
bolted t~ and/or eng~ged ~rom the bottom with the upper
portion of the casing~ The power supply coul~ in this
instance extend through the molded ~ody and through the
lower portion of the aasing to the outside of the device.
An ON~OFF switch as well a~ the button actuator of a
C~cuit brea~er or the like could be arranged on the upper
portion o~ the casing.
~ ith r~speot to special ~inds of applications
e~ploying hazardous o~ especially aaustic fluids and with
respe~t to the exchangeab~lity of the heating element it
will be further advantageou~, when for purposes of safely
~eceiving the container, a cup is provided which can be
in~erted i~to the re~ess or into the spac~ formed ~y the
heating element, and which i3 adapted substantially to the
shape o~ the con~ainer. ~his cup will then be placed on
the aloth covering the heating element, and is thereby
largely secured against tipping. Hazardous ~ubstances
whiCh may exit from the container or outflow therefrom at
a brsakage of the container, will be caught by the cup, 50
as to exclude a ~oiling or even destruction of the aloth
on the one hana and of the heAting element on the other.
As regards caustic substances the cup could be made o$ a
high grad~ ~tee~.
Finall~, within the 5COp~ 0~ a ~uxthRr
ombodi~nt~ it is po~sible to aon~t~t th~ mold~d body o~
th~ d~vio~ in aaoordanco w~th ~he invantion also in two
parts. In this in3tanae, the ~ub portion forming the
reaess an~ la~gely a~apted to the shape of the aontainer
could be ~upported by an i~dependent oupport portion
prefQra~ly construated in ring ~hape. Last not least for
pUrpOS~5 0~ ~avlng material, the tub pnrtion could be
:
2:~Q78~ ~
; 6
provided with an ou~er wall substantially par~ l to the
recess or inner wall, it being only nece~a~y to ensure
t~at the wall ~hicXne~s o~ the tu~ po~tion i5 dimensioned
such t~at a laboratory container i~ held adeguately and
safely. This configuration of the molded body a~lows to
reduce in any event consider~bly the ~aterial necess~ry
~or it8 manufacture, thereby decreasing t~e manufacturing
costs altogether.
Various possibilitie~ exist to advantageously
con~igure and fu~ther develop the teaching oP the present
invention. To this end, re~erence may he made on the one
hand to the clai~s dependent from claim 1, and on the
other hand to the following description of two embodiments
o~ the invention wit~ ~eference to the drawing~ In
conjunction with the description o~ the preferred
embodiment of the invention with reference to the drawing,
also generally preerred e~bodiments and ~urther
j develop~ent~ of the teaohing are descxibed. In the
drawing:
Figure 1 is a ~che~atic, perspect~ve view o~ an
embodiment of a dev~ce in accordance with the invention
for heating a ~ontainer with an inserted container;
Figure 2 is a schematic ViQW, cut and enlarged,
of the embodi~ent of Fig~re 1:
Figure 3 shows a heating ele~ent o~ the
embodi~ent o~ Figur~ 1 constructed as a tubular heating
elementt
~ igur 4 i~ a ~chQmati~ ~ectione~ ~ie~ o~ tho
molded body oP the embodlm-nt o~ ~lgur0 1; and
Fig~e ~ is ~ ~ohemat~c, ~o~tloned view o~ a
bip~tite molded body ~ second embodi~ent o~ a deviae in
accordance with the invention ~or heating a contain~r.
Shown in Flgure 1 iB a schematic ~iew o~ a
d~vic- ~or heating a l~boratory container 1. ~hi~ device
oompr~--s, ~ ~ho~n in Pigure a, a molded ~ody 2, ~hloh ~
again provided with a recess 3 ~or re~ei~ing the
lab~ratory container 1. For heating a heati~g ele~ent ~
i~ used which is c~n.~tructed as a tubular heating element
and adapted -~ub~tantially to the ~hape of labora~ory
container 1.
Shown in both ~igure 2 and Figure 3 is that
heating ele~ent 4 iæ spirally arranged in recess 3 of
molded body 2.
In accordance ~ith the invention, the heatin~
element ~ is atta~hed with its end 5 forming the opening
for laboratory ¢ontainer 1 to a retainer ~ing S which is
bQst seen in Figure 2. This retainer ring 6 ha~ at least
a ~light~y larger diameter than recess 3 o~ molded boqy Z.
As can be noted by way of indication in Figure 2, the
localizing of retainer ring ~ on the upper edge region 7
o~ molded body 2 permits the heating element ~ to extend
into re~e~s 3 such that, as it heats up, it is allowed to
exp~nd ~dequa~ely to~ard the wall and bottom o~ ~olded
body 2.
Further #hown by wa~ ~ indi~ation in Figures 1
and 2 i8 that the heating element ~ is loosely covered
with ~ cloth 8 overlying the upper edge region 7 of molded
body 2. Furthermore, the ~olded body ~ is sur~ounded by a
casing 10 which extends with a ri~ 9 at least in part over
the upper ed~- r~glon 7, the cloth 8 being clamped ~etween .
the upper edge r~gion 7 of molded body 2 or retainer ring
6 and rim 9 o~ t~e ca~i~g.
As can ~urther be no~d ~rom Figu~e~ 1 and 2, a
~eal ~ ar~anged b~tween ca~ing ri~ ~ and upper edge
r-gion 7 ~ mo~aed bo~ 2 or cloth 8 extending the~eover.
A3 i~ ~urthe~ ~hown in Figure 2, the ~eAl 11 ~5 mad~ as a
ga~ket with a thi~ker ihner ring portion 12 and a thinner
outer ring portion 13, the latter being arranged on the
~dg~ region 7 below casing rim 9 and the thicker ihner
~ng portion extending outside casing rim 9 toward receQs
8 ~1~7~
3. With ~espect ~o the materia~s used for the ~anu~acture
of the individual components and ~ith respect to the
conRtructional configuration of ca~in~ lo reference may be
m~de ~o the general description.
Finally ~hown in Figure 5 i~ a furthe~
embodi~ent of the device in ac¢ordanoe with the invention,
in which the molded body 2 is con~tructed in ~wo parts. A
tub portion 1~ fo~ming recess 3 is supported in a
prefe~ably ring~shaped support portion 15. ~he tub
portion 14 comprises an outer wall 17 ~ubstantially
p~ral~el to ~ece6s 3 or inne~ wall 16, the wall thickness
of tub portion 1~ being dime~sioned suoh that a laboratory
container 1 is held ~de~uately and safely.
In conclusion, it ~hould be noted that ~he gist
o~ the present in~ention in accordance with claim 1 is by
n~ means limited to the ~oregoing e~bodi~ent. ~or
example, it is quite possible to conceive a device of the
p~esent in~ention also without the casing, it being in
this instance necessar~ that the molded body ~ave a
co~responding ~trength ~nd possibly a coating. For
example, in this instance it would be possible to secure
the clo~h in po~ition by an 8djusting ring or the like,
w~ich could in thi~ instance ~e placed on the upper edge
region of the ~olded body.
