DE2135342C3 - Laboratory thermostat - Google Patents

Description

4 ι ü ^tra g ^u "g to keep at a constant temperature-

7. Laboratory thermostat according to claim 6, the recipient, z. B. a reaction vessel used characterized in that the connection 50 dete liquid through a dip tube heater element (D) as a plain bearing for which the circulation is heated and in which mostly the for pump (1) driving shaft (4) is designed circulation of heating fluid required centrifugal

o ι V ' · pump is only partially filled with liquid

8. Laboratory thermostat according to claim 7, filled. This has the advantage that the shaft driving the connecting pump does not have to be connected to a plugging element (D) with concentric tubes with at least a bushing or another shaft seal and a ring connecting the containers (A, B) , First of all, it is considerably enlarged (Fig. 3b). the engine power and second - especially at high

1 ^La * ^{) Oratorium} thermostat according to claim 7 heren operating temperatures - a higher Auföder 8, characterized in that the upper 6 ₀ wall would be required for construction and maintenance mareil the slide bearing than the other container (B) chen. The open design, on the other hand, has been implemented (FIG. 4 b). the disadvantage that the heating fluids used

10. Laboratory thermostat after one of the constant contact with the air above it

Claims 1 to 9, characterized in that are exposed and especially at higher tem-

the heating device (S) is in one of the 6 _S temperatures in the form of vapors or fine mist

a · container (A) spatially separated; with which - get into the laboratory room,

the third container (A) connected to it- Since not all laboratories have strong effects

th container (F) is located (Fig. 5). Zugsvorrichtuneen · are available - and also not

need to be ζ. B. in physical laboratories -. this leads to a considerable annoyance. and possible damage to the health of the person. J _n More recently, so some manufacturers of laser _{(boratoriumsthcrmostatcn} gone over the fjeckcl to provide the device with a cooling device, which the harassment by oil mist or oxydalive decomposition products of Wärmetrü ^ rflüssigkeit diminish, but can not eliminate it. The contact of the When the heat transfer fluid is hot with the air in the gas space of the thermostat, the transfer fluid wedge undergoes a progressive oxidative change, which results from the increasing darkening and / or thickening of the fluid and the occurrence of volatile, unpleasant smelling and the respiratory tract irritating products of decomposition and oxidation noticeable Ir mBcht. When using silicone oils as heating and heat transfer fluid can almost unhindered access of humidity, a be-Sleu.iigte cause polycondensation to rubbery masses. Sometimes form, I ^ ter the innuence of Luftsauctoff also un.ösl.che Abschei -

"The object of the invention is to create a laboratory thermostat of the open design, in which an after-S - e Development of disruptive vapors and neutrons as well as the formation of decomposition? and oxidation products, Polycondensation products, insoluble Excretions and the like are avoided.

This task is performed in a laboratory thermostat. aten dei Ar, fiction _b eS solved in that the Wämu transfer fluid tank divided into two separately arranged containers, of which "one contains the circulating pump and the heating device and connected to the inlet and outlet openings for the heat transfer fluid circuit is, and related with the ambient atmosphere of which has the cooling device of the other, and that the container has a passage-permitting of heat transfer fluid connects are ■ dungselemwnt connected via at least comprising a mixing of the heat transfer fluid components in the

^ iWai JJl, WM.7 uwi V- "-.» ».» ... -. ... _ _

Device known in which a heat transfer fluid with the help of a pump is passed through two containers one after the other, one of which is one Contains cooling device, and in which housed a heating device in a further third container is. However, beer is in contrast to the present Invention there is no connecting element between the containers that make the passage the heat transfer fluid is allowed, but mixing of the heat transfer fluid components largely prevented from the individual containers.

According to the invention it is ensured that there is no hot surface of the heat transfer fluid that comes into contact with the surrounding atmosphere. The ones in the fastener provided liquid passage openings are in their number, their diameter and their Length, based on the properties of the heat transfer fluid that changes in volume when the thermostat is operated the heat transfer fluid which is connected to the thermostat ^ (temperatures that end in \ lower Henaiians occurring turbulence and the KUhlleistungsunfc αβ ■ m Upper container provided Kün.vorrlcmunfc «ib

fits. ,., .. ,, "" ",," !, »ment

In the simplest case this is a tie-in element

one between the two vessels angeoraenu.

Partition wall with at least one ottoman.

The connecting element can also be an aitwm Hose connecting the container or a Konr w.. The tube can öcnaiicrnm cooled by dc-n

carried out and in which in the BcnrtlterJWt "'

Part of the pipe can be drilled ^νοΓ Β ™ η seiu.

This embodiment has in particular the vo.i.

a low heat exchange between un

Holders. . , “Ίπποι man

Geiangi to a compact construction ».

if the ^umwä ! ^Zpum LmTbzf the Im »« through the at least ^ ° " ^mn f..r ^ \ ° _{and that of} the at least one pipe Sf ¹ """'; ¹ _c , .. _Tchmes . Diameter of the opening or the I »» ^rc! ^ J, ser of the pipe is greater than the measurement e ^ Woe

^^^^^ j ^ between the drive shaft and opening or inner tube ... .'- step through.

The connecting element can also be formed as a Jj for the WeHc driving the circulation pump Riches at least one of the Be at binding bore. With this: r ™ ^ * form, a smooth run of the drive shaft y is guaranteed. .

The plain bearing can also ^m .
see pipes with _? 2
binding annular gap

special Β? ^ ¹ ^^^^ A " ^fbau ^ to e.ncm special ^ lu'TS of the plain bearing as langt""when the upper J '^ _H ° SoS _chtIing upper container is a ^ biWet. Uie η _dem

the thermostat is preferred

lower container ^ J ⁰ J ¹ - " ¹ ""provided. This connection standing'Behalf provided ^^ execution form has dm Vorto

P ^ P '^ X ^^^^ r execution are g "* ^" J »j ^k ^ ^ -vilzpump be short, Ä- and resonance phenomena

_{the lower} container container connected,

"Young intended · » A when the heat-developing

avoided ^we ™ ^e "

Next
or des
one

be this m
thermostat

the
one

the heat can overflow. Heat transfer fluid

. ^De ^ _t jJ ^ Ster can with an introduction en.ha «>» »JJ« «J 'j other indifferent raw" jjSttctatoff or em ^^ _{an At} .

^ HT ^ SiA ^ another indiffemosphare of: wicks ¹⁰ J ' _hd chilled warrente. G «^ jg ^ SgT ^ i, so that these robbers ^t * W ™haben ^ £ _äk nichi with ^

In order to transfer the turbulence in the un- or a measuring device or the like.) Connected, z. B. with

lower container to the upper container to reduce using hose connections (metal hoses)

the, can be radially arranged or fixed pipelines in the upper container,

Nete vertically standing sheets be arranged. The circulation pump 1 is in the operating state

To also the heat transfer due to the 5 the heat transfer fluid from the thermostat

Keeping heat conduction as low as possible can promote this to the recipient and back again. the

Connection element from a heat-insulating return is connected to the lower container / i

Mal'srial, for example polytetrafluoroethylene, best; therefore the one in the upper container B takes

hen. not borrowed part of the heat transfer fluid or

The schematize in the drawings.! shown »o only a very small part of the cycle

Embodiments of the invention are in the fol- and remains infoi.je a built-in cooling device

described below. tungC is cold or only moderately warm, depending on the

In Fig. 1 is an inventive thermostat trnsität cooling C, depending on the temperature of the part under shown in which two cylindrical containers A circulation of the heat carrier and B by means of a flange centrally disposed 15 liquid and depending on the length of the cylindrical between the tube D are connected, through the tube D and the shaft 4 located intermediate interior, the drive shaft 4 of a circulating pump 1, space.

For example, a centrifugal pump, with a certain amount of leeway, which takes place by means of heating device 5, so that a liquid introduced into the heating process expands the heat exchanger lower container A without much liquid, so that the liquid level in the ßen resistance - ie so that no container B in container / 4 rises so far that part of the liquid overflows beyond the static pressure of the liquid at E. At the overflow E there will be an overpressure - through the connection, therefore, a transparent branch pipe D can expediently rise into the container B. Connect the hose that leads to a collecting vessel. The length of the pipe D determines - for a given as z. B. a bottle or a can. The respective level of the liquid and heat exchange between the liquid in the container B can be easily checked by means of the diameter - essentially the extent of the sight glass 9.
Tanks A and B. Since the exchange will be the clearance between the connecting pipe D ring as low as possible, as long as possible pipe D would be upstream and the felt ¹ through 4 of the shaft Umwälzteilhaft. Nevertheless, for reasons of consolation, one becomes a pump! should be so far that the heat transfer and the handiness of the thermostat prefer the carrier liquid with full heating power during the generally short pipe D of a few centimeters heating process from the heated container A without hindrance and prefer to extend the exchange into the cooled container B , reduce by a small diameter. In the ex- ie with such a low resistance that in the container A trcmfall it is sufficient if the length of the pipe I) is only 35 no overpressure arises even if the depth is a few millimeters or more. That is, if the mostat is connected directly to the two containers A and B on a closed heating circuit, for example on the heating or cooling jacket of the and only through a pierced reaction vessel. In the rain! it is sufficient if disc that z. B. expediently because of the better inside diameter of the connecting pipe D, the length of the opening is the release ducts between the containers A and P, depending on whether or not the pipe is separated from other insulators holding connecting elements D are provided through the thickness, 0.5 to 5 mm or when given this cutting disc. The connection is slightly larger, for example 0.5 to 4 mm larger, than the element D in the sense of the invention can therefore be in the Ex diameter of the shaft 4 running through it be the drilling wall between the two containers A and B. Rung 10 of the connecting pipe D in the outlet

The compound is one in Rohrd allgineinen of Figure 2, 4a and 5. The Quite the same material führungsbcispiclcn prepared from the well diameter of the holes 10 should, for example, the containers A and B consist of 0.5, that is z. B. made of non- and 4 mm, preferably between 1 and 3 mm, Herostendcm steel or brass, nickel-plated and / or 50 gene, depending on the size of the heating power and depending on the chrome-plated, but it can also be made of suitable poly number of holes. )

mcren materials, e.g. polytetrafluoroethylene, bc- You will get the holes 10 or the clearance

which have the advantage of a lower heat transfer between pipe D and shaft 4, which is not unnecessarily large.

have bearing. chcn because the exchange (diffusion or convection

Before putting the thermostat into operation, the 55 lion) between the two containers A and B are possible.

after this execution boispic! one above the other should be kept small. With executions

orderly and through the pipe /? together VCR gcmiiß Fig. 1, it is expedient in the containers B

Bundcncn containers A and B as far as the vertical thin metal sheets arranged radially

The liquid used previously. e.g. to build in hochsic- (»baffles«) in order to allow a rotation of the

dcndcn mineral oil fractions, Diphcnyl-Diphcnyloxid- 60 liquid in h to prevent.

Mixtures, silicone oils filled, that the oil level In the container A can except the Heizvorrich-

a cooling device 6 can be provided with the aid of a swing S attached to the container B, which

glascs9 becomes visible. If there is no Sch & uglas9 available, it can be connected when the thermostat is on

dcn, then one fills through one of the connecting pieces -7 or 8 so winding back-up feet are connected.

long WärmcUbcrträgerflüssigkcit until it at 65 when the thermostat for a long time ^ ^'u' ihcn

overflow /? begins to exit. At the inputs and temperatures z. B. 200 to 300 "C operated ·...:. Dcn

Outlet openings 2, 3 is the one at constant Tcmpc- should, one can protect the heat transfer «i ... trllüs-

ralur to be held recipient (sin Rcaktionskcssel sigkcit dnduich perfect that one is the obc-

7 8

Ren container B closed with a lid and a Fig. 3 and 4 is shown). When shaft 4 introduces relatively different gas, e.g. nitrogen, at 11. tively long, it can be expedient to also guide, weld or glue it to the lower end firmly with the container B , through a counter bearing 16, since the pressure as shown schematically in FIG . 2 is shown.
equal to the atmosphere through the overflow E 5. Also with regard to the heating and control elements can or / and through the opening in the cover, through all proven in practice or for the practice through which the shaft 4 is passed, is given ¹ . Embodiments and embodiments that appear useful and the embodiment according to FIG. 2, the rations are combined with the nitrogen thermostat according to the invention introduced through a gas inlet pipe 11.

and through a bore 12, and the overflow pipe £ ίο When in Fig. Za exemplary embodiment illustrated

discharged again. In this way, every contest of the laboratory thermo-

cycle of the heat transfer fluid with the Sauer- staten consists of the lower container A with the

substance of the Lu.'t avoided. upper container B connecting and opening

The operation of the thermostat according to the invention holding element D in a plain bearing for the

under a nitrogen atmosphere there is by no means an emergency shaft 4 in which there are a number of bores 1 ·

agile, but only one in continuous operation, through which the heat transfer fluid

Recommended measure, which is only then possible without major resistance from container A to container

it is possible that as a result of the inventive ter B can arrive (and vice versa). Instead of the bo

Arrangement of the surface of the heat transfer fluids 1 · in the plain bearing - or in addition to these

The liquid in the container B remains cold, however hot in the- «o - you can add another pipe or more to the side

The more the liquid is in container A. Unwrap connecting pipes D ί . The plain bearing can

Since due to the structure according to the invention in this embodiment, to a large extent »

of the thermostat the hot heat transfer fluid half of the the cooled heat transfer fluid

speed at any point with the ambient atmosphere containing container B , so that it also

comes into contact, can - even without In- * J being cooled.

gas atmosphere - the disadvantageous phenomena such as fig. 3 b illustrates, the plain bearing of conventional laboratory thermostats, such as fog bil-, can also be designed as a concentric double tube with a ring manure and oxidative change in the heat gap as an opening, whereby the transfer fluid can be exchanged with the outer tube through spacer bars even at high operating temperatures, not adjust. The advantages of being open without having 30 is associated.

Shaft sealing operating mode of operation remain in FIG. 4 a illustrates that the container

fully raised hen. ter B by no means always concentric - with respect to

The embodiment of the shaft 4 or the container A shown in FIG. 2 may be arranged

Laboratory thermostats according to the invention are a must. Such a non-concentric arrangement

differs from that in FIG. 1 shown in the we- 35 can because of the simplicity of the execution

essential in that the lower container A can be advantageous when the thermostat cover is in place

connected to the upper container B by a pipe D, so especially with larger Ί nermosta-

is that is passed through the container B. The sliding plate arranged next to container B

So that in the embodiment according to FIG. 2 one in A obt is expedient in this embodiment.

introduced heat transfer fluid through the 40 ßigerweise also cool.

Tube D into the container B - and back again - The exemplary embodiment in FIG. 4 b shows a can pass, are located in the loading according to the invention in Rehälter B laboratory thermostats 10 at-sensitive part of the tube D bores This was formed to the upper part of the sliding bearing as a container B embodiment of the connecting element D has. The openings for the liquid, the advantage that the exchange of liquid and heat, are located as bores IS ir. The exchange between the channels A and B is relative to the wall of the slide bearing. Through the overflow E it is possible to ensure that when the 1 nermosiaien is heated, that the base plate 13 carrying the motor 14 does not run the heat transfer fluid uncontrolled here on the one passed through the container B over the edge of the plain bearing. Such a tube D is attached and not (as in the embodiment with an extremely small volume of the container example in FIG. 1) with the help of the lateral ters B can be advantageous in special cases if there are webs 15, only that in the case of the invention it is important to save space.
Laboratory thermostats numerous variations The size ratio of the beWen container / * in the construction details are possible without and B can be varied within wide limits, without changing anything in the principle of the invention. For example, the motor 14 can also be impaired with the aid. In general, is that of a container B located at the upper edge of the container B has less space reasons · execute flange to be attached. Other construction than the container A, for example, in the volume ratio variants are that the drive motor 14 V _A IV _B - 20/1 to 5/1, in extreme cases, as in the circulating pump 1, not on or on the thermostat βο embodiment of the Fig. 4b, for example, but also up to ten itself, but in the Laborato- 200/1. Experience has shown that the work rien the usual way on a stand rod of the laboratory with the thermostat according to the invention particularly attached to a table and a movable coupling, is convenient. if the container ß is so large that the eg a piece of vacuum hose or a double oil level can be achieved even with a rapid gimbal coupling, with the shaft 4 of the circulations the temperature of eg 5 1. .. M) C, the ■! Pump 1 is connected. In this case, when carrying out chemical reactions, the shaft4 is guided through a sliding or / and ball bearing or McDrcilicr, often necessary, not on a * urid retention (as in the execution examples iScr level underneath the connecting element D resp.

9 10

holes 1 · in the connecting element D off (*? mkt Kon. That would refilling of Wärmeüber- clock thermometer in the reactor) men carrying out chemical reactions. The less necessary in this carrier liquid. In this case, one must take into account the volume of the circulated heat, so that the volume of the entire transfer fluid is, the faster the heat transfer fluid often responds to a multiple of the 5 thermostat on impulses from the control system.
\ Thermostat volume can be. The volume of the thermostat according to the invention

In the embodiments of FIGS. 1 and 2 fen is divided in the embodiment according to FIG. 5

^: are the diameters of the cylindrically executed on the two containers A and F. At the in

Containers A and B are the same size. However, this is not a construction shown in Fig. S eliminates the need for greater P need. The container A can also - like the outer part of the volume on the container F. It is shown, for example, in FIGS. 3a and 4a - however, the construction can just as easily have a larger diameter than the container that both containers / i and F equal to ^m th B. Since, has the advantage that it is the Kontaktther- or the container A is greater than the container F. thermometers 18 directly into the container A immerse in Fig.5 the two containers / 4 and F are rigid

can serve. On the other hand, it is in many cases "15 connected to one another by the pipe section 17, and - especially with the isothermal lead-through" red - the whole arrangement is advantageous in a reaction with insulating material - a box made of sheet metal that is as stuffed as possible to circulate a small volume of oil, because it can also be made of plastic. Is reduced in viedie inertia of the thermostat, len cases it may be appropriate _t the two bed. E., The device switches more rapidly by heating to Küh- ao holders A and F m greater distance from each other len to when one by the "light-off" To set up exothermic or to fasten to stand rods and men reaction heat is released, in which case the contact thermometer 18 - or at least to connect it through a flexible, insulated metal hose.

one of several contact thermometers - not also the type of connection of the recipient should

in the thermostat, but rather in the interior of the 95 by Fig.5. One can - immersed the reaction vessel. if for any reason it is expedient

It is generally customary for laboratory equipment to just as easily connect the recipient directly to the thermostat, the circulating pump 1, which is usually connected as the circulating pump. A centrifugal pump is carried out by the recipient, and the heating device then accommodates the heat transfer fluid in the container 5 together in a container. 30 terF and from there to the container A or to the Um · In the construction according to the invention, it can be a circulating pump. No matter how the containers A and F are arranged, the requirement is always met that a 'circulation pump 1 and the container A introduced liquid' (or a heating device 5 in FIG Spatially separated containers are to be accommodated there by heat-expanding liquid) tern A and F and this passes through rigid 35 through the connecting element D in the cooled pipelines 17 or through movable hoses container B.

with each other to connect, the container A with the umsthermostaten containing the Behäi- iemente Regele As used in Laboratorikalte Wärmeüberträgerriüssigkeit associated usually mercury Kontaktter B 1 the circulation pump thermometer containing coupled to a solenoid relay. The advantage of this arrangement is above all. The contact thermometer 18 can be inserted directly into the iem in that the circulation pump i and heater? Immerse container A , but it can also be accessible from outside, so that it can be easily installed and removed independently of the container A in a lateral connection or one another. Another advantage at some point in the circulatory system is that the drive shaft 4 of the container F in the embodiment according to FIG. 5 is particularly short and can therefore be found with longer ones.

Waves sometimes annoying oscillation and resonance If, as in the exemplary embodiments

nancant phenomena are avoided. One can thus Fig. 1 and 2, the contact thermometer 18 is located outside almost without any additional structural effort, the output of the thermostat container A must be increased by the circulation pump to a multiple of the standard output of Labo-50 a simple electrical circuit that ensures that the heating circuit is increased immediately interrupted without wasting the total volume of the thermostat if the circulation pump fails for any reason (e.g. by increasing it, since the dimensions of the container F, which is spatially separated from the container, are relatively small) ,
let hold. As has been shown in practice, it is advisable to apply the heating to a thyristor circuit in a known manner with the aid of a transfer fluid, if the demands on the temperature are particularly high located share concerns - with arrangements conclude that the heating output is continuously reeulated according to the type of Fi g. Reduce 5 to below 1 1. can be, always only a small part of the

This is of great advantage when using high preselected heating power to regulate the temperature-sensitive media, such as B. Siükonöle, and generally temperature by the contact thermometer and einaebei using the thermostat for isothermal switching.

For this purpose 2 sheets of drawings

Claims (6)

1 2 patent applications · 1J laboratory thermostat according to one of the H claims 1 Ws 10, characterized in that 1. Laboratory thermostat of the open construction - the one container (A) and / or the third container has a cooling device (6;) with a heat transfer fluid container (F). Heating device, cooling device, temperature 5 12. Laboratory thermostat according to one of the control element un <i circulation pump, characterized in that claims 1 to 11, characterized in that marked that the heat over- the other container (B) with an overflow (E) carrier liquid container is provided in two separately. ordered container (A, B) is subdivided, from de- 13. Laboratory thermostat to one of the nen the one (A) the circulation pump (1) and the % a claims 1 to 12, characterized in that Contains heating device (5) and with the inlet and in the other container (B) a gas inlet Outlet openings (2, 3) for the heat pipe (11) opens (Fig. 1 and 2), carrier fluid circuit is connected, and from the 14th laboratory thermostat to one of the those of the other, with the ambient atmosphere claims 1 to 13, characterized in that related (B), the cooling device 15 in the other container (B) arranged radially, (C), and that the containers (A, B) are arranged over perpendicular metal sheets, at least one of the * passage of heat via 15. Laboratory thermostat according to one of the carrier liquid permitting connecting element claims 1 to 14, characterized in that (D) are connected which a mixing of the connecting element (D) from a heat-heat transfer: Ä'gerfiüssigkeilsantejle iv the container insulating material, for example Polytetratern (A, B) largely prevents. fluoroethylene. 2. Laboratory thermostat according to claim 1,
characterized in that the one container (A) arranged under the other container (B) is. _a5 3. Laboratory thermostat according to claim I. or 2, characterized in that the connection- The invention relates to a Laboratorysthcr- dungseiement (D) a partition wall with at least a mostat of the open design with heat exchanger Opening is. carrier fluid container, heater. Tempera- 4. Laboratory thermostat according to claim 1 30 turrcgclelement and circulating pump. or 2, characterized in that the connection While one for the implementation of chemical dupgselcment (D) a hose or pipe is seen reactions or procedural opera- (Fig. 1). at constant temperature in production 5. Laboratoriumsthermostati according to one of the drives - and mostly already in the Technikumsbe-claims 1 to 4, characterized in that 35 drive - used closed stationary systems, the connecting element (D) through the other is required for the implementation of measurements container (S ) and in the part of this EIe- portable thermostat, which is handy in and reactions in the laboratory and located in this container (B) , to which the holes (10) to be heated are present (Fig. 2, at and at certain temperatures to operate-4 ^a '"· 40 the apparatus can be easily connected. 6. Laboratory thermostat according to one of these laboratory head thermostats (see. F. Kohl claims 3 to 5, characterized in that rausch: Practical Physics, Vol. I, 20th edition the shaft (4) driving the circulating pump (1) (1955), pages 45 to 47; Houben-Weyl: Methods through the connecting element (D) through the organic chemistry, Vol. 1/2, (1959), p. 657 bis leads and the diameter of the opening or 45 660; H. Römpp: Chemistry Lexicon, 6th edition, the inside diameter of the connecting element (Vol. IV, Col. 6471) are usually larger when open as the diameter of the shaft (4) is ben, i.e. i.e., the containers in which the heat transfer