DE76C - Dryer - Google Patents

Description

1877.

Class 82.

GEORG CRESPEL in FRANKFURT a. M. Drying Apparatus.

Patented in the German Empire on July 8, 1877.

The accompanying drawing shows the dryer connected to a balance. FIG. 1 is a side view and FIG. 2 is a top view, while FIG. 3 is a side view of a somewhat modified apparatus.

It consists of the actual dryer A and the balance B, which are both firmly connected to each other.

The gas burner a is located under the drying apparatus A , instead of which there is also petroleum, spirit, more tensioned. and blown steam can be applied with little change in apparatus.

In the outer cylinder bc of the drying container a square container (at high pressure with chemical balances a round one) is inserted in such a way that a space remains between the floor and the walls, which is filled with water through the pipe hi.

The apparatus is provided:

ι. With the named pipe h ϊ for the inlet of the water (funnel) and discharge of the steam at high pressure with tap k. .

2. With the air heater d, which is above the gas burner α and regulated by the taps e and / respectively. can be shut off and the hot air leads into the drying room through the pipe g.

3. With the thermometer /.

4. With the water level pipe pi * m. This indicates that the water level is too low in the case of low-pressure apparatus, since then, after the water has fallen below m , steam comes out at m ^l , in which case water must be poured in.

5. The cover η ' η made of double polished sheet metal and interposed wool insert serves to prevent cooling by radiation (polished surface) as well as by conduction (wool).

6. For high pressure is on the device:

a) the manometer O;

b) the adjustable safety valve /.

This serves on the one hand for the safety of the device, on the other hand mainly to the to regulate the pressure which determines the temperature, so that one can do so with insignificant Pressure compensate for the loss of heat caused by cooling and exactly 100 ° can hold than with strong pressure up to 16 ° and more, so that this apparatus for the laboratory uses the oil and calcium chloride baths and has the advantage of being at any temperature necessary for drying can reach and hold on to a degree;

c) a water level faucet with a wooden handle (to prevent burns) - glass float or some other device for detecting the water level.

In the accompanying drawing, the balance B is a pointer balance which, if properly executed, offers many advantages for this purpose.

The weighing pan q hangs on the pin r in such a way that it can be taken out and re-attached so that it can be filled with the material to be dried. It is carried by the wire that goes through the lid (slot). The balance is in equilibrium when q is loaded with 20g.

At the top is the tare cup q ¹ ; the same is used to apply tare weight to prevent the loss of water if it exceeds 25 pCt. is to be compensated, (5 g are to be added to q '). Even if you, which is often the case with voluminous or sword-drying bodies, a smaller weight, e.g. B. puts 5 g on q , the balance equilibrates by 15 g on q '.

B has an axis s that runs in two bearings χ w attached to the tubes h . B also has a scale t which gives decigrams very precisely. Since the weighing pan is at its lowest point with a load of 20 g, the balance still gives _1/2 ρCt. exactly what is sufficient for almost all technical purposes.

The pointer u ' is distinguished by the fact that it rotates about the same axis as the balance, i.e. always remains parallel when it is adjusted.

But it should be noted in particular that it consists of two sheets u'u ² lying one behind the other, which are aligned parallel and at right angles to the axis s.

In this way, in spite of the distance of u * from the balance beam, any error (parallax) that is inevitable with ordinary pointers is made impossible.

Instead of this scale, the following is used:

For fine analysis a chemical balance is then given a vertical lift.

Furthermore, the spring scales are similar in shape to Salt's letter scales for domestic use Purposes because, while not very sensitive and reliable, it is simple.

In ^FIG. Very suitable for this purpose 3 shown eccentric balance (quite new) and consists of:

i. Cylinder a, 12 cm in diameter, 12 cm in length, made of thin white sheet metal to be exactly cylindrical, with two straight bottoms. Ax b, which is inserted with an eccentricity (the smaller it is, the more sensitive the balance is) of 2 mm, passes through it. As a result, the cylinder is in stable equilibrium with the pointer at d. Now the pointer h , made of thin cast steel wire and bent at the end to avoid parallax, shown in side view in FIG. 4, is attached to the cylinder at b , goes on the scale i; Further, the scale depends on e g with a thin silk thread :; likewise the counterweight /, which is adjusted so that when the weighing pan is loaded with 20 g, the pointer is at k . If a body (20 g) to be dried is now placed in the bowl g , the cylinder and pointer begin to move as it decreases in weight. Indicates water content.

Also a horizontal dryer with a scale with rider's weight that you can move in and out of can push out is useful, although less expedient.

Use of the device:

i. Determination of the water content ..

a) Fill with water.

b) One heats.

c) Maii lays as much of the body to be dried in the weighing pan, so that the pointer is on 20, after you have placed a 2 ο - gram weight probiit has whether the scales are correct; if this is not the case, one can adjust them with the pointer or with screw and barrel weights. The weight can also be reduced by tare in the tare cup.

d) The temperature in the apparatus rises to 100 ° and the weighing pan as a result of the lighter weight due to water loss goes up and shows the water loss on the scale in Grams and decigrams. In chemical scales, the loss is on the tare pan tared, which is why it does not matter whether the balance arms are of the same length or not.

2. To determine the specific gravity (also with 100 ° dried substance it can be determined).

The drying room is filled with water, the body is placed in the tare dish (5: 10:20 g) and then into the lower bowl. The loss of weight on the scale gives just as accurate the specific gravity as the water loss. For this purpose, however, it is an empirical one Scala attached showing all the errors of immersing the bowl (constant), the balance rod (changeably) corrected.

With it one can in a moment the specific gravity of the heaviest bodies, z. B. Gold (the scales immediately distinguish the true and false pieces and give the Scala on how much the fineness is missing), as well as the specifically easiest to determine.

For this purpose I sheet drawings.