RU2067455C1 - Steam sterilizer - Google Patents

Abstract

FIELD: devices for sterilization by saturated steam fed from a steam generator, drying at a pressure below the atmospheric one without employment of a vacuum pump. SUBSTANCE: to reduce the time of the drying cycle and simplify the design, cooling water is fed directly to the space between the pressure chamber and insert through an injector. EFFECT: simplified design. 1 dwg

Description

 The invention relates to a device for sterilization with saturated steam supplied from a steam generator, drying at a pressure below atmospheric without using a vacuum pump.

 Currently, steam sterilizers are equipped with water-jet vacuum pumps and liquid ring vacuum pumps to create a vacuum in the chamber in the preparatory phases before sterilization and during the drying phase after sterilization.

 In classical sterilization, the sterilization cycle has a sequential course of the same phases: triple removal of air from the sterilization chamber by means of steam supply and deaeration; sterilization; suction of steam through the pump to vacuum; drying when the pump is in operation during drying; air supply.

 Steam and air are removed by a water-jet pump with a high water flow rate at a minimum pressure of 0.3 MPa or by an expensive liquid ring vacuum pump, which requires electricity and water to operate. The control of the sterilization cycle can be manual or automatic.

 The disadvantage of all of these currently used steam sterilizers is a complex and expensive device to remove air and to create a drying process, as well as high water consumption.

 The above disadvantages are eliminated by a steam sterilizer (a.s. N 218452, Czechoslovakia, class A 61 2/00, A 61 2/10), the essence of which is that an insert is installed in the pressure chamber, a cooling coil is placed under it, and in its lower part there is a pipeline for removing air ending in an ejector entering the cooling chamber in which the cooling coil is located.

 An advantage of the steam sterilizer according to the invention is that the control of gravitational air removal during the preparation cycle usually replaces three times the air removal with steam filling up to excess pressure. Creating a vacuum for the drying cycle is carried out using a cooling coil.

 The main disadvantages of this sterilizer are: 1) the length of time to create a vacuum in the sterilizer, because the steam cooling process in the sterilizer is carried out through the coil wall (low heat transfer coefficient); 2) the complexity of the manufacture of the coil, high water consumption and high material consumption.

 This design as the closest in technical essence adopted as a prototype.

 The purpose of the invention is the creation of a steam sterilizer with a minimum drying cycle time, simplifying the design.

 The goal is achieved in that the cooling water is directly introduced into the space between the pressure chamber and the insert.

 The drawing shows a diagram of a steam sterilizer.

 The sterilizer consists of a cover 1, a pressure chamber 2, inside of which the insert 3 is axially mounted. In the cavity of the insert 3 there are nets 4 with the material to be sterilized, forming the working space of the sterilizer 5. The insert 3 in the upper part has an opening 6 for passing steam into the working space of the sterilizer 5 and steam leaving it during drying.

 A steam supply pipe 7 is connected to the pressure chamber 2 with a steam supply valve 8 from the steam generator 9, a reducing device 10, a water supply pipe 11 that ends with the nozzle 12. The nozzle 12 is located in the lower part of the sterilizer between the pressure chamber 2 and the insert 3. On the supply pipe Water 11 is a water supply valve 13, which regulates the flow of water. Air is sucked from the environment into the air supply pipe 14 through a filter 15 and a valve 16.

 A pipe 17 is installed in the lower part of the pressure chamber 2, through which condensate and air are discharged through the heat exchanger 18 and the condensate drain 19. The heat exchanger 18 is connected to the cooling water supply pipe 20 and the cooling water drain pipe 21. After the condensate drain 19, the pipe 17 is bifurcated to the condensate discharge pipe 22 with a valve 23 and an air outlet pipe 24 with a valve 25. A safety valve 26 is installed on the cover of the sterilizer, which operates when the pressure in the sterilizer increases.

 The device operates as follows. Open the steam supply valve 8 and the air outlet valve 24. The steam from the steam generator 9 enters the space between the pressure chamber 2 and the insert 3, then rises and heats up both the pressure chamber 2 and the insert 3, and then passes through the holes 6 in the upper part insert 3 and enters the working space of the sterilizer 5.

 Air is gravitationally squeezed out and discharged from the working space of the sterilizer 5 through the air outlet pipe 24 until clean steam flows. After removing air from the sterilizer, close valve 25 on the air outlet pipe 24. An increase in pressure by a predetermined amount occurs in the sterilizer. The sterilization cycle occurs when the pressure is automatically maintained at a predetermined value for a certain time.

 After the end of the sterilization cycle, they start drying. Close the steam supply valve 8, open the valve 23 on the condensate outlet pipe 22. The steam passes through the heat exchanger 18, condenses, then the condensate is discharged through the condensate drain 19 in a reverse cycle. When the pressure drops to 0.01 MPa, the valve 23 closes and the water supply valve opens. 13. Water passing through the nozzle 12 is sprayed in the space between the pressure chamber 2 and the insert 3. Water droplets (aerosol) in contact with the steam cool it. When the steam cools, a vacuum forms. The smaller the size of the cooling water droplets, the larger the contact surface of the phases, the faster the cooling of the steam occurs and the consumption of cooling water decreases. Steam from the working space of the sterilizer through the holes in the rate enters the zone of reduced pressure. Thus, the drying step occurs.

 After the drying process is completed, valve 16 is opened on the air supply pipe 4. Air passes through filter 15, valve 16 and enters the sterilizer until the pressure in it reaches atmospheric pressure.

 This ended the cycle.

 This invention can be used to sterilize instruments, cotton gowns, surgical gloves, etc.

Claims (1)

 A steam sterilizer comprising a pressure chamber with a cover and an insert, a safety valve, pipelines for supplying water and steam, condensate drain, means for cooling the working chamber, characterized in that the insert is installed coaxially with a gap relative to its walls, holes are made in the upper part of the insert for the passage of steam, the means of cooling the chamber is a device for spraying cold water in the gap between the insert and the walls of the chamber.