DE1238153B - Process for drying leather or other flat goods - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

C14b

German: 28 b -17

Number: 1238153

File number: K 53053 VII a / 28 b

Filing date: May 29, 1964

Opened on: April 6, 1967

The invention relates to a method for drying leather or other flat goods, using a vacuum drying device, the material to be dried after the drying process is moved out of the vacuum drying device and cooled.

In known drying devices of this type, for example, the leather to be dried on the heating plate, which consists for example of aluminum-nickel or copper and is heated by steam, hot water or electrically, is placed wet and ejected, ie the leather is covered with woods on a flat surface stroked under strong pressure, whereby the surface of the leather increases. The disadvantage here is that when the leather is placed on this hot plate, the surface of which can be up to 100 ° C., ¹ a corresponding water evaporation occurs immediately on the leather side facing the heating plate. This sudden action of heat causes a considerable shrinkage of the surface before the leather is wedged between the heating plate and the vacuum contact device. This area shrinkage is synonymous with a loss of material and should be avoided during drying.

Leather drying systems have also become known, which work according to the so-called pasting process and an area shrinkage of the Avoid the above-mentioned type as far as possible. In this process the leathers are placed on glass plates glued and slowly dried in humid air. This procedure and associated devices have However, the great disadvantage that a great effort and large dimensions of the devices are necessary for implementation. In the known vacuum systems of the usual type, this can Land gain cannot be achieved. The strong shrinkage is mainly due to the laying on of the cold damp leather can be traced back to the hot heating plate. It is not possible to workaround that way to create that the heating plate is cooled before laying the leather and the damp, cold leather is brought to a heating plate surface at room temperature, after ejecting the machine cover closed and the vacuum applied immediately and thereby the leather before the start of the Heat influence between the heating plate and the machine cover is clamped, - because it is at This process requires the heat stored in the heating plate before each new application of a Leather, i.e. to be removed before each work cycle by cooling and at the beginning of the drying process Process for drying leather or other flat goods

Applicant:

Erich Kiefer ventilation systems G. m. B. H., Gärtringen

Named as inventor:
Walter Schmid, Gärtringen

to feed again. Since also the heating plate is off

ao heat and strength reasons has a significant mass, arise for the heating and cooling large time delays and energy losses that lead to uneconomical work to lead.

The present invention has therefore set itself the task of providing a method for drying leather to develop in which the strong shrinkage that otherwise occurs in a vacuum drying device the dry material is largely prevented.

According to the invention this is achieved in that the material to be dried prior to the actual drying process at room temperature on a thin, unheated or cooled platen made of known material thermally conductive material is applied and ejected.

The new process has the advantage that there is no "heat exposure to the dry goods takes place before it is held on its base by the vacuum contact device.

The method according to the invention has the further advantage that the action of heat on the Dry goods, in particular because of the additional thin plate, did not occur suddenly, but rises rapidly to a final value. During the somewhat delayed evaporation of the water builds up the vacuum and the shrinking of the dry goods is prevented. The delay in water evaporation has a very beneficial effect on leather in particular. In addition, the platen turns out to be also in the case of the cooling process taking place outside the device, the < follows the drying process, which is very advantageous because the material to be dried must

709 548/63

3 4

not removed from a hot plate, no shrinkage occurs because none yet

and the support plate stands for the next dry-shrinkage-causing influences or forces

process are already in a cooled state. After completing this preparatory

coincidence. The support plate 18 will work with the leather 19

The method according to the invention can be carried out by means of 5 into the drying device by means of traction drive 20

a device as shown in FIGS. 1 and 2 to be retracted. This is achieved by having both

is seen to be carried out. thin plates by a rope or a chain hoist 20

F i g. Fig. 1 shows a device for the implementation connected by the pulleys 21, 22

of the process is guided in a partially cut side and 23 and is attached by a roller 24

opinion; io being driven. This roller 24 is driven

2 shows a partial section through the heating motor 25 and through a changeover motor 25

Support plate with closed lid. comes to the upper-

The device consists essentially of the surface of the heating plate 3 to lie. The lid 7 of the The actual drying device with two side-drying devices is immediately arranged loading and unloading stations 1 and 2 in sequence. Both 15 closed, the vacuum applied and the drying stations are designed as work tables, whereby the process is initiated. The platen 18 is through the two table tops with the surface of the heating - the already hot heating plate 3 heats up quickly as they Plate 3 of the drying device lie in one plane. has relatively little mass, which on-die The heating plate 3 does not always need to be warmed in a planar design. In the short time it takes to to be. You can also have a concave or convex 20 heating of the thin support plate 18 is necessary Own surface. The heating plate 3 is already so strong a vacuum that Insulation 4 surrounded and in a frame to two significant contact pressure by the not shown Stands 5 stored. The frame also has two flexible and adaptable rubber plates with the Column guides 6, in which columns 6 'act vertically sieves in the cover 7 on the leather 19 and it are moved up and down, the cover 7 of 35 due to the vacuum between the rubber plate and Wear drying equipment. The columns 6 'are pressed by a support. The external pressing forces over one Traverse 8 connected, which weigh on a Hubzylin- against the internal shrinkage forces and the 9 is attached. Actuate the piston to prevent the leather from shrinking. With this one this cylinder can thus be the lid of the drying process, initially for heating up the device be lifted off. When turning off the 30 position plate 18 needed a short time so that the Lifting cylinder 9, the cover sinks due to its own contact heat effect, which does not suddenly occur, weighty on the heating plate 3 and is against the steadily increasing up to the set end value, Dry material 19 pressed. The cover 7 is on its which can be up to 100 ° C., for example. Circumference on the underside with a seal 10. The water evaporation also takes place as a result see who delay the interior between cover 7 and 35, which affects the leather itself qualitatively Heating plate 3 seals airtight, and has a very beneficial effect on it. The little loss of time to Inside with not shown rubber plates and heating of the thin support plate can through Equipped with sieves, which affect the dry goods 19 higher treatment temperature at the same time hang up. Exposure to vacuum can be compensated. Around

As can be seen from Fig. 2, is through the 40 between the heating plate 3 and the retracted

Seal 10 to the outside closed space via thin support plate 18 direct heat conduction

the grooves and grooves 11 with an annular channel 12 are to be obtained in the heating plate 3 grooves or

Connection milled over the connecting line 13 and grooves 11, which may cause air bubbles

- as in Fig. 1 can be seen - via a water drawer and the support plate 18 without gaps

separator 14 connected to a vacuum pump 15 45 rests.

is. The connection with the ring channel 12 on the die during the drying process of the leather 19 will change Side of the heating plate 3 is through the pipe steaming water is over the side in the heating 16 schematically indicated In the heating plate 3 itself plate 3 located slots and annular channels 12 are included Cavities 17 are provided through which either the vacuum pump 15 is discharged. The Superheated steam or hot water directed for heating 50 Separation of the water by the water separator, or electrical heating elements of FIG. 14 are made therein. After completion of the dry housed. On the heating plate 3 is an additional process, the cover 7 according to the previous one borrowed thin support plate 18 made of sheet metal, on which the switching off of the vacuum by pressing the lift dry goods 19, for example leather, applied cylinder 9 raised, the support plate 18 with the will. Through the vacuum connection, the leather 19 is thus through the traction drive 20 after the Cover 7 extended together with the thin support plate 18 opposite unloading station 1 and the dry material 19 firmly on the surface of the and there by cooling action to room temperature Heating plate 3 pressed. cooled down. To make this drying process effective and

To make the working method according to the invention quick, the table tops 26 are as follows in front of you: the thin support plate 60 or unloading devices 1 and 2 as gratings 18, which are designed to protect against material damaging influences, which are covered by perforated plates the dry material 19 is resistant, rests on the hole and terminates a cooling air line 27 Sheet metal plate 26 of the loading or unloading device 2. Since it is preferably fed by a fan 28, the perforated sheet metal plate 26 darch the blowing with simultaneous with the extension of the first support room air is cooled, the operation of the 65 plate 18 is the second support plate 18 on the Placing, spreading and pushing out the opposite side retracted, so that no time is lost under normal room temperature conditions. stands. Pulling off and reapplying with So leather can still take place on this cold support plate 18 during the time in which the second support

Claims (1)

Plate is retracted together with the leather 19 for the drying process in the drying device. Claim: Method for drying leather or other flat goods using a Vacuum drying device, whereby the goods to be dried after the drying process from the Vacuum drying device is extended and cooled, characterized in that that before the actual drying process, the material to be dried is placed on a thin, unheated or cooled support plate made of known thermally conductive material is applied and ejected. Considered publications:
Austrian Patent No. 194,784;
British Patent No. 460,437. 1 sheet of drawings 709 548/63 3.67 © Bundesdruckerei Berlin