Abstract: The invention relates to a method and to a device for freeze-drying products using a chamber (1) having surfaces (2), whose temperature can be regulated, and condensation surfaces (5). Water penetrating from the product in the form of vapour condenses on the surface of the condensation surfaces, and measurements are taken on the documentation of the process during the freeze-drying process. The aim of the invention is to improve the freeze-drying process in relation to the documentation thereof and, at the same time, to reduce technical complexity of the device which is suitable for carrying out said method. As a result, running of the vapour flow is determined between the product and the condensation surfaces (5) and the amount of water penetrating from the product in the form of vapour is calculated by means of temporal integration.

Abstract: A chamber for a freeze-drying device with storage surfaces, whose temperature can be regulated, for containers containing the product that is to be freeze-dried. The chamber includes an optical shield comprised of shield components, whose temperature can be regulated. The shield is positioned between the storage surfaces and the interior wall surfaces of the chamber.

Abstract: A method for determining the residual moisture content during secondary drying in the dry product of a freeze-drying process is disclosed. In order to determine the residual moisture content without interruption of the drying process is suggested that the desorption rate is measured at certain intervals (for example 10 minutes) during the secondary drying phase. A computer calculates from two or several of these measured values the time at which a desorption rate would be reached (desorption rate zero point) which would alter the desired residual moisture by only a tolerably small amount. The respective residual moisture is determined by the computer by chronological integration of desorption rates from zero point until the moment of measurement taking.

Abstract: In a method for controlling a freeze drying process, a frozen product is arranged on temperature controlled surfaces (12) in an air-evacuated chamber (1) and undergoes a main drying and after-drying phase. During the main drying phase, the temperature of the ice surrounding said product is continuously measured. The pressure in the chamber and/or the temperature of the surfaces are modified during transition from the main drying phase to the after-drying phase. In order to avoid longer idle periods between the chamber (1) and the evacuation device (3, 4, 14) and to determine transition from the main drying phase to the after-drying phase, the pressure and/or the temperature of the surfaces during said transition are modified according to changes int he temperature of the ice.

Abstract: A humidifier and heater for air to be inhaled for connection to an inhalation conduit of a respirator comprises a housing having a bundle of vapor permeable fiber tubes which have evaporation fiber wall surfaces extending therethrough. A packing is arranged adjacent each end of the housing in said tubes and seals the space in the housing around the tubes between the packing. The tubes in the interior of the housing in the space have a coating on their exteriors of at least either copper or silver. Warm water is circulated into the housing in the space around the tubes and the inhalation air is directed through the tubes or vice versa.

Abstract: The humidity exchanger for a breathing apparatus and a conduit for the passage of inspiration and expiration air comprises a housing having an opening at each end and with a bundle of fiber tubules extending longitudinally through the housing and embedded at respective ends in packing so as to define a space within the housing around the tubes. Inspiration air is directed upwardly through the tubes past a non-return valve and out through a fitting which also forms a passage for the expiration air. The fitting also extends in communication with an inlet for the tube chamber, the space in the housing around the tubes and between the packing. An outlet is also provided for the chamber around the tubes which extends out to atmosphere.

Abstract: A humidity exchanger for a breathing apparatus includes an outer housing having one end with an opening for the passage of inspiration and expiration air therethrough and an opposite end into which is fitted a separate inner housing. The inner housing carries a first tube bundle of fibrous tubules defining passages therethrough for the passage of either inspiration or expiration air. This passage contains spaced apart packings through which the tubules extend and spaced between the packings defines a heat exchange space around the tubules. Construction includes an inner tube or conduit centrally of the bundle with a passage of heat of the inspiration or the expiration air into the space surrounding the tubules within the inner housing. The inner housing leads into a front space of the outer housing through a conduit connected to the user of the apparatus.

Abstract: A protective breathing device comprises a housing having a filter therein and with an inlet air passage through the filter and through an internal passage in the housing to a breathing tube having a mouthpiece which is adapted to be fitted to the wearer. The breathing tube includes an exhaling valve for expelling air which is exhaled through the breathing tube. The housing carries an oxygen cartridge which is fired or opened by a firing pin which penetrates the cartridge in order to supply oxygen into the housing passage for flow through the breathing tube when this is necessary. In addition, the housing has an annular chamber surrounding the inhalation duct carrying an economy bag through which portions of the exhaled air may be recirculated for flow back into the breathing tube on a successive respiration in order to maintain the oxygen content within acceptable limits.