DE1920555U - DEVICE EXAMINATION OF SAMPLES WHILE HEATING IN A VACUUM, CONSISTS OF A FURNACE AND A MICROSCOPE, INSIDE A PRE-VACUUM CONTAINER. - Google Patents

Description

PATENT LAWYERS "·"'"' ^» I * 1 5. 4. 65

DR. WP RADT
DIPL.ING. EE FINKENER

Bochum ^Di Pl - Ing. W. Ernes ti

Heinrich-Koenig-Strasse 12
Telephone: 4 15 50, 4 23 27

109

üki ... IdS ^ HI-il '^. L ¹ EaG-EEGrIE viiOkl- ^ lJE

-inl ^ ge to the laiki-oskopischen or other observation of in objects located in a sealed chamber

irici-it ^ t: France, February 2, 1962

The invention relates to the systems for

^ ii: ro3l £ opisci "ien or other observation of objects located in a dense environment, in particular strongly oxidizable oils and alloys, in particular of ; :: temperatures take place, so that because of the ability of these parts to oxidize, work must be carried out in a vacuum.

The aim of the invention is in particular to circumvent the difficulties encountered in the known

.uis guides w ^ r to find a jc-s to install a heated chamber in which a

For this purpose, according to the invention, such iailw .._ ön samples and the vacuum chamber containing them are arranged within a tight chamber, in particular a ri ^ iidsuhuhkcistiiis, and at least the largest part of the iaikrosiioi-'ij oaer β ± ΔΘί> other observation device is attached outside ae.3 U ^ iIdSChUiIkU-Stens, with facilities vorgebe ^ or. sinu, soft an adjustment, in particular a trans-I ^ xiüi; ab3v, e _o ui-g, aes lens of the observation device towards G.UX ¹ uuroli the Vcdcuuiakdinner and their specimens-formed solid uu-di-diation eriiiüung.

jjie jjirxigung is explained below with reference-Uwih: .i3 -uf c. ± a drawing as an example.

i'ig, 1 is a partially cut

oeit ^ i- ^ nsioht an insert according to the invention 2 for microscopy j ^ ioGJieii observation of samples of radioactive metals, which are subjected to warming in a sealed chamber v; eraen.

Pig. 2 shows individually in a perpendicular

dohi-itt the furnace arranged in this chamber for heating uyl "j." X 'O \ j ü ο

Ii ¹ Ig. -j and 4 are two fc> cu.alfbiläer of the erj-iiidUi- ^ sgemuisen Äege! institutions.

! 'ig. 5 is a temperature rise curve.

The invention is hereinafter in its

..- jiv / accurate on aie microscopic examination of an er- Wo.rm.un.-; subjected samples of rcxdioactive metals to

purifies.

It should first be noted that such

Metals are generally highly oxidizable, so that these Heating in a vacuum and with the lowest possible residual pressure must be made.

There are also the oxides that are formed.

are often in powder form, must be worked in a "glove box to protect the operator against radioactive dust:

These special conditions therefore lead

usually to place a microscope in the glove box and attaching the heatable vacuum chamber to the stage or the stand of the microscope, resulting in large Difficulties, because the stage and thus also the Vacuum chamber for exploring the field of view must be adjustable in relation to the lens.

In order to remedy these disadvantages, the invention is in accordance with the invention proceeded so that the tight chamber is fixedly arranged in the glove box, while the Microscope is attached outside this box, whereby Means are provided, by means of which his (e.g. the box tightly penetrating) lens opposite the Chamber and the sample can be moved for examination.

For this purpose, the microscope is carried by a plate, for example, which can be attached to an outside at will the glove box lying Hal'ifer can be adjusted, whereby the micrometric transverse displacements des- üht'ersu- · '"" " chungsliclitbündels are produced. "If further with - polar-

The microscope is supposed to be used with controlled light a rotatable lighting device which interacts with a corresponding licol or polarizer can, these facilities are also outside of the glove box, so that ultimately all manipulations made on the microscope outside the glove box will.

The above conditions can be realized in various ways.

In the case of the in 2 ¹ Ig. Embodiments 1 and 2, there is a tight chamber for receiving the robe 1 to be inspected 1 ^(S! Ig. 2) for example, of a cylindrical body 2, which _ * n its two ends with the interposition of seals 5 through two floors 5 and 4 is tightly closed, with the boaen 3 for the microscopic examination containing an opening which is closed by a plane-parallel quartz plate 6.

This plate is on the appropriate floor attached by gluing or welding.

Chamber 2 is a line 7 with you

a motor pump unit 8 for generating a high vacuum connected. Also at 9 is a trap with liquid nitrogen shown. With such a device there is no contamination of the flow circuit for the liquid nitrogen on.

At 10 and 11 there is an © ionization manometer or an auxiliary crucible to be used for certain processes shown. If, in particular, the structure of the metal being examined is to be made visible, this helps

crucible the attack by a volatilization of a salt produced gaseous phase.

The chamber 2 is expediently double-walled and is cooled by a water circulation.

The sample 1 to be examined, which a.B. as in Pig. 2 illustrated by a holder 2 is carried, which runs out in clamping jaws 13, v? elche grasp the sample with its ends. This type of attachment ensures a reproducible setting of the sample in relation to the optical axis of the system, which is maintained while heating, the sample can learn to expand freely without causing thermal stresses. as a heat source, which the sample to the "desired temperatures." brings, z. B., as in Pig. Shown in 2 is an oven used with a helical heating resistor 14, which is arranged between reflective metal screens 15 » This heating resistor is preferably made by a chrome-plated ladder formed and has an insulating sleeve made of ■ Magnes! ^. powder and an outer sleeve made of a metal of the under the I ame η "Iconel" known type "· .. -"

It can also be used at high temperatures

To avoid any interfering metallization, a tungsten resistor should be used, as this metal retains very good mechanical resistance properties when it is warm.

The helix can then be twisted with the help of platinum attached to a rod made of -iluminium oxide ".

! It should also be noted that the "metal" of the Sample 1 by the Klennifbäekeir on part 13

a very thin! foil made of a suitable metal is insulated will.

The above sealed chamber is on a holder

16 attached, which is attached to columns 17 which pass in bellows 18 through a glove box 19, which the Chamber and the parts connected to it.

At 20 one sees the implementation of the line going to the trap 9 with sealing bellows 21.

The microscope for observation by the 4uarzienster 6 is designed as follows:

It is carried by a plate 22 which is arranged on a table 23 outside the glove box 19 is, and its lens 24- can pass through a corresponding opening 25 in the wall of the box that it is the Window 6 opposite. Sealing bellows keep the glove box tight at the point where the microscope passes through upright.

In the embodiment shown, the

The body or tube 26 of the microscope is connected to the plate 22 by a micrometer block 27, and the seal of the Glove box is made by bellows 28, 29, which the body 26 with the Eand of the opening 25 as well as with the connect optical system.

To enable the postponement of the se-

siclitsfelds and thus the exploration of the entire surface Devices are provided for the sample which move the plate micrometrically, e.g. by means of the ivicrometer screw 30, whereby the plate rests on the table 23 via blocks 31, of which z. B. may be three.

- ^r ) _

can also., especially if with polarized Light should be worked, a rotating lighting device can be provided in combination with one or more polarizers or Nicols.

In the embodiment shown, you can see

at 32 the eyepiece, at 34 a polarizer and at 33 a Polarization interferometer. The polarizer 34 cooperates with the polarizer 35, which in FIG. 4 is a lighting device 36 is installed and cooperates with a prism $ 7, where the entire arrangement can be rotated around the axis of the tube with the aid of ball bearings 38, while the tube 24, 26 itself is not rotatable.

With such an arrangement, the

Handling of the microscope apparently completely outside the Glove box, with all the usual observation techniques can be used, in particular by rotating the lighting device and lighting with polarized light.

Furthermore, this handling has no. Influence on the tightness conditions of the glove box 19 and the tight chamber 2.

It should be noted that the use of the apparatus requires prior degassing of the heating chamber 2, yours Oven 14, 15 and the trap 9 makes it necessary.

Removable heating elements, not shown, are used for this.

Column 1? rest on the ground. Since they

are not connected directly to the glove box but via bellows 18 or other intermediate parts, as a result

the lack of rigid connections does not transmit vibrations, which could be disturbing for the photomicrograph.

The glove box itself rests on Missen 39.

Incidentally, the heating devices can be from

be different from those shown. For example, induction heating or the heating by electron bombardment can be used.

With the above arrangement it becomes expedient

a system for self-regulation to maintain the temperature combined to the desired adjustable values. This system contains thermocouples, which with corresponding Control relays interact.

It can be particularly interesting to obtain a temperature rise according to a certain Eurve, in particular a linear increase in temperature T in puncture time t, e.g. according to Eurve C of B'ig. 5 such, that sections P of constant temperature occur, which cause a transformation of the metals or alloys to be examined correspond.

For the production of the Eegel system e.g.

an inventive arrangement can be used in which two voltages can be switched against each other, namely a comparison voltage, which e.g. from a level resistor comes, v / which by means of its slide generates the particular linear change in this voltage, while the other Voltage is taken from a thermocouple, which is exposed to the temperature of the furnace, which electrically through a heating circuit is heated, which by a second

Variable resistor is controlled, with drive devices are provided which are controlled by the 'error voltage resulting from the comparison of the two above voltages and in particular operate the aveiten rheostat in such a way that that the desired heating temperature is established at any time will.

These latter devices contain e.g. a drive system which is in one or the other Direction by one influenced by this error voltage Voltage relay is activated and the controller of the second level resistor, "in particular in the form of successive pulses.

The above training is based on a first Implementation shown in Fig. 3 as follows " light.

The first variable resistor 41 is through a

Voltage source 42 fed. Its slide is e.g. Synchronous motor IL driven, the speed of which is selected according to the desired temperature rise curve. The voltage at the terminals of the resistor at a-c- is the above comparison voltage.

This voltage is switched at b against the voltage, many being generated by a thermocouple, which is exposed to the temperature of the furnace and in particular welded to the heating resistor 14 of the same.

Those in the circuit a-b-c; occurring

Error voltage then actuates the voltage relay 46, which ge opens an independent electric circuit 47 according to its purpose or closes which one or more JJinsch.altre.lais

holds whose coil "is visible at 4-8.

This latter relay is set e.g. in the

specified below quietly in one or the other Sense the drive system for actuating the slide of the second variable resistor 4-9 in operation, which the voltage of the heating circuit 14- fed e.g. from the Hetz S.

The drive system includes a motor Mp with

two windings 50 and 50 'for the two directions of rotation. This The motor drives the slide of the Hegel resistor 4-9 and is controlled by a switch I from the relay 4-8, whereby however, he also depends on breaker contacts which are controlled by the motors mentioned below.

There are two more motors m ^ and aip

present, which are controlled by a second switch i through the relay and by crouching C ^, Op contact sets 52, 53 and 52 ', 53' control, the first motor itu for one specific direction of rotation of the motor IL (winding 50) and the second motor nip effective for the other direction of rotation (winding 50 ') will.

There are two cams G * which

at the same time open a contact 52 and another contact 53 close. The same goes for two floors as regards Gp of contacts 52 ', 55' · The cams have in each pair a corresponding angular position.

The above arrangement works as follows, for example:

If s.B. the switchover relay I-i

- 1 Ί -

next is in the 0-1 position, as in Pig. 3, the following processes take place when the cams C ₁ pass in front of their microcontacts 52, 53:

The stitch A-B-G: opens at 52, but

the rotating motor now continues to rotate because it is driven by the mesh A-C is fed.

The mesh Ε-ϊ-Φ closes, however

53, so that the motor M 2 is fed through its winding 50 and during the closing time of the contact 53 the moving arm of rheostat 4-9 drives.

The same processes play a role

every revolution of the motor, from which a pulsed, i.e. a sudden change in the voltage at the terminals of the oven bed 14 results. This continues until the electricity is in Stitch a-b ~ c- changes direction "so that the switches I-i come to 0-2.

The motor m- then stops while

the motor m _o goes into operation in order to generate a corresponding operation with the winding 50 'of the motor M ₂ and with the contacts 52,' 52 'and 53, 53'.

It should be noted that the engine is only

when the cam CL passes, which the Stitch A-B-C opens and stitch E-F-G closes. In this Position, the arrangement is ready to immediately transmit a pulse when the changeover relay makes contacts I-i switches back to 0-1. So there is no dead time, which is one of the advantages of the "multiple motor device" above.

Ultimately leads in a state of equilibrium

the arm of the rheostat 49 has a reciprocating motion about a position of equilibrium. Sine inclination of the Oven for cooling or heating has a change the period of this movement.

In such a device e.g. there are two rates of change of temperature, one of which is 100 ° C / h and the other is 200 ° G / h. The speed of the motors driving the cams is e.g. one revolution in 6 seconds. The cams have a working angle of around 15 ° represent.

Records the temperature as a function

over time in a furnace of the above type show a temperature fluctuation of the order of magnitude, with the drift of the curve being zero.

In the device of FIG. 3, in which If the control effect occurs without delay, an interruption period can be used on the order of 30 seconds. This period is large enough to cause a slight delay to allow the control effect, which simplifies the device E.g. the following design is permitted.

In this embodiment, at v / elcher also at 50 and 50 'the two windings of the motor M ₂ ^{driving the variable resistor b} S are shown, the two windings are switched on one after the other by means of a single cam C, which has two "contacts 53 ₅ 53 '"" operated and constantly driven by a motor m.

Depending on the position of the changeover relay
the corresponding winding is energized during the passage time of the cam. In the worst case, the control action takes place with a delay which is equal to the time
which the motor driving the cam needs to perform one revolution (this is the case in which the changeover relay changes a position at the moment in which the action of the cam on the corresponding switch ceases).

Although this system is less accurate it is
it is suitable for numerous i? äl, le.

The above system has numerous advantages over the known systems of this type, in particular the following:

It enables convenient handling of

outside the glove box, it facilitates assembly, especially the sealed chamber and its furnace, and provides favorable conditions for the "regulation" of the furnace.

Claims (2)

Γ. H, 3 £ I TO 3 w £ J / © VlKr Amtl. Aktζ .: G 10 155 / 4-2h Gbm Our Aktz .: 63 109 IPR / 'DB (new) protection claims 1. Device for examining samples with heating in a vacuum, consisting of one inside a fore-vacuum container arranged furnace and a microscope, characterized in that the furnace provided with an observation window (6) (14, 15) inside the container, which is closed by means of elongated bellows (18, 21, 28, 29) and is under a preliminary vacuum (19) is arranged and that the objective (24) for observing the sample (1) is used, otherwise outside the container (19) located microscope by means of a sealing membrane (29) the wall of the Container (19) penetrated. 2. Apparatus according to claim 1, characterized in that support columns (17) are provided on which both the Both the microscope and the vacuum oven are at rest and the containers (19) under a preliminary vacuum go through, the passage points of the container walls (19) by means of suitable membrane seals (18) Are completed.