DE2333755A1 - DESKTOP STERILIZER - Google Patents

Description

DIPL.-PHYS. F. ENOLlCH βο34 unterpfaffenhofen July 2nd, 1973

PATENT Attorney 0 Q Q Q 7 ζ ζ postfach E / Ei

TELERON 0811/84 3β 38

TELEGRAM ADDRESS: PATENDLY MUNICH DIPL.-PHYS. F. FINALLY. 8034 UNTERPFAFFENHOFEN. P.O. BOX

CABLE ADDRESS; PATENDLY MUNICH

TELEX 5 212 3Ο8

My file: S-3255

Applicant: Sybron Corporation, 1100 Midtown Tower, Rochester, NY 14604, USA

Table sterilizer

The invention relates to a table sterilizer with a water storage container and a heating device for evaporation of water in the sterilization chamber.

Such known sterilizers are normally designed as a unit and contain a water reservoir so that no water pipe connection is required. The supply of Water into the sterilization chamber is done by opening a valve so that water from the storage container can flow into the chamber. The valve is closed again as soon as the user has determined that there is a sufficient water level in the chamber is. The sterilization cycle is then started by turning on a heater in the chamber to generate steam. At the end of the sterilization cycle, the steam is released through a cooling coil in the reservoir to recirculate the water to enable. In known sterilizers of this type, it is considered disadvantageous that manual operation of the valves is required.

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It is therefore the object of the invention to design a sterilizer of the type mentioned in such a way that a fully automatic operation is possible by adding a predetermined amount of water to the sterilization chamber at the beginning of each cycle is initiated further with the help of a device, which device automatically by the water supply in the water storage tank refilled at the end of each cycle.

This object is achieved by the subject matter of claim 1.

In summary, therefore, the essential features of the invention can be seen in a table sterilizer, the one automatic refilling device for supplying a certain amount of water in the sterilization chamber at the beginning of each sterilization cycle. The refill device contains a water tank with a predetermined volume that is completely emptied into the sterilization chamber at the beginning of each cycle and at the end each cycle is partially refilled with condensed steam and partially with water from a separate reservoir.

In one embodiment, a measuring cylinder is located in the water line between the storage container and the sterilization chamber Use and a magnetically actuated piston in the cylinder use. When the cylinder with water from the reservoir When the sterilization cycle is switched on, the magnetic coil is activated. This causes the piston to inject the water in the cylinder through a valve into the sterilization chamber, where it is vaporized by a heater. At the end of the sterilization cycle, the valve is switched on via a temperature or Pressure sensor actuated to release the steam in the storage tank, wherein at least a portion of the vapor passes through the graduated cylinder first. By the vapor pressure in the measuring cylinder the piston is pushed back and the cylinder is suspended. By cooling the cylinder, a negative pressure is created through which water from the storage tank enters the cylinder for each work cycle is sucked in.

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In another embodiment, a water tank is provided with a certain volume, from which through The effect of gravity water gets into the sterilization chamber, as well as, means for completely emptying the contents of the container into the sterilization chamber at the beginning of each cycle. By another device draws water from the storage tank in order to mix it with steam, which at the end of the cycle is drained from the sterilization chamber. Water and condensed steam withdrawn from the storage tank are fed directly into brought the container until it is completely full, so that a predetermined amount of water in the container for the next Duty cycle is present while the amount of water flowing out of the full tank is returned to the storage tank will.

The invention is to be explained in more detail, for example, with the aid of the drawing. Show it:

Fig. 1 is a schematic representation of an embodiment of a table sterilizer according to the invention; and

FIG. 2 shows a view corresponding to FIG. 1 of another exemplary embodiment.

The illustrated in Fig. 1 table sterilizer 10 contains a sterilization chamber 12, the filling opening through a Door 14 is lockable. There is an electric one in the sterilization chamber Heating device 16 arranged. Various types of compartments or holding devices can be used in the sterilization chamber Items to be sterilized must be indicated. The entire sterilization chamber is covered by a partially shown thermal insulation layer 18 surrounded.

There is a water reservoir in the sterilizer arranged, which is connected to a cylinder 24 via a line. A cooling coil 26 forms one end of the line in the storage container. The line itself contains a throttle device 28. The cylinder 24 is connected to the bottom of the sterilization

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Chamber 12 connected to a line 30 having parallel branches 3 0A and 30B. The flow through these branches is operated by a solenoid valve 32 and check valves 34A and 34B controlled. The line 30 is connected to the bottom of the sterilization chamber 12 via a sump 36.

A piston 3 8 arranged in the cylinder 24 is actuated by a solenoid 40 which is attached to the outside of the Cylinder is arranged. To adjust the piston stroke, the Piston has a threaded shaft 42 with an adjustable stop 44.

Contains the control device for the sterilizer a push button switch 46 and a switch 48 for a detection device for the pressure or the temperature in the sterilization chamber. The push button switch 46 used for commissioning controls the operation of the coil 40 and the heater 16 via circuits 50 and 52, respectively. The switch 48 controls the mode of operation of the solenoid valve 32 via the circuit 54.

For the operation of the sterilizer it is only necessary to keep the storage container 20 filled. this can be done periodically, which is usually at least daily. The cylinder 24 is filled by pushing the piston by hand is shifted into the position shown in FIG. 1, or by filling water directly into the sterilization chamber 12. After that, the Chamber 24 is automatically refilled at the end of each sterilization cycle, as will be explained in more detail below. When the cylinder the initial filling with water, the commissioning can take place after closing the door 14.

The push button switch 46 is actuated to initiate the sterilization cycle. This energizes the solenoid valve 32 and moves the valve flap to the position shown in dashed lines. The solenoid 40 is also energized, thereby moving the piston 38 to the left in FIG. As a result, the contents of the cylinder 24 through the line 30, the check valve 34A _x the branch line 30A and the sump 36 in the

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Sterilization chamber pressed. By pressing the push button switch 46 the heating element 16 is also supplied with power. The generation of steam in the sterilization chamber causes the air in the chamber displaced upwards and drained through a vent valve 56 at the top of the sterilization chamber. Because of the check valve 34A in the line 30 and because of the position of the valve flap of the solenoid valve 32 shown in dashed lines can then no steam flows back despite the steam pressure building up.

The length of the sterilization cycle can be determined by the temperature of the saturated water vapor in the sterilization chamber 12 to be determined. The duration of a cycle can, however, also be determined as a function of time or pressure. Once the temperature has risen to the desired value, which indicates the completion of the sterilization, the temperature switch 48 is actuated. As a result, the circuit 54 is interrupted and the solenoid valve 32 is switched off, so that the valve flap is in the extended position Lines shown in Fig. 1 position returned. This allows the steam through the sump 36, the line 30, the check valve 34B, cylinder 24, throttle device 28, line 22 and through cooling coil 26 back into the reservoir. When the steam exits the sterilizing chamber 12, the pressure reduction along with the heat content of the sterilizing apparatus acts the evaporation of condensed water in the sterilization chamber.

The actuation of the switch 48 by the temperature sensor connected to it also opens the circuit 50, whereby the solenoid 40 is switched off. When the coil is de-energized, the steam entering cylinder 24 pushes the piston 3 8 to the right in Fig. 1. The passage of steam through the line is throttled by the throttle device 28, so that saturated water vapor is present in the cylinder 24. Through the gathering steam in the cylinder causes not only the return stroke of the piston but also heating of the cylinder.

As soon as all the water vapor has been diverted into the reservoir, the cylinder 24 cools down, so that a smaller one

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Underpressure is created, by means of which water is sucked into the cylinder through the line 22 and the throttle device 28. Since the Cylinder 24 contains saturated water vapor is condensed by the Water vapor and the water sucked in, the cylinder is completely filled with water. Therefore the cylinder becomes automatic refilled and is ready for the next work cycle.

If desired, the storage container 20 can be cooled , for example with the aid of a fan 58. The mode of operation of the fan can be, for example, by means of a temperature sensor can be controlled depending on the temperature in the storage tank, or the fan can be connected to the circuit 50 must be connected so that it runs during the sterilization cycle.

If desired, venting can take place at any point in time by means of a device for opening the Push button switch 46 is provided. If a sterilization cycle is to be aborted, it is usually not all Water that has been fed into the sterilization chamber evaporates. In In this case, the water that collects at the bottom of the sterilization chamber 12 and in the sump 36 is caused by the pressure in the sterilization chamber pushed out.

In the embodiment shown in Fig. 2, a container 60 is provided with a known volume. Adjacent A storage container 64 is provided on the container 60, into which water can overflow via a side wall 66. The measuring container and the storage container do not have to be designed as a one-piece vessel, since a different one in the case of a separate arrangement Means can be provided in order to introduce the water overflowing from the measuring container into the storage tank into the storage tank.

The measuring container 60 is arranged above the sump 68 of the sterilization chamber 62. A line 70 connects the measuring container with the swamp.

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A second line 72 is connected to line 70 and the Inlet of an ejector 74 connected. The suction line 76 of the ejector 74 protrudes into the storage container 64. The outlet 78 of the ejector lies above the measuring container 60.

A three-way solenoid valve 80 is used to control the flow through lines 70 and 72 and a check valve 82 is. arranged in the line 70.

The construction and operation of the embodiment in Fig. 2 is simpler than that of the embodiment in Fig. 1 because no piston is required and by itself gravity water can be passed from the measuring container into the sterilization chamber. The measuring container 60 must initially filled to the point of overflow. Since the entire content of the Container 60 is drained into the sterilization chamber at the beginning of each cycle, ensures the filling of the measuring container up to to overflow that the same amount of water is fed into the sterilization chamber with each cycle. The overflow into the reservoir 64 is done to such an extent that the inlet of the suction line 76 is covered, and preferably this tank practically is completely "filled.

After the objects to be sterilized have been arranged in the sterilization chamber 62, for example a not shown Pushbutton can be actuated to initiate the sterilization cycle. At the beginning of the sterilization cycle, the valve flap of the solenoid valve 80 from that shown in solid lines Adjusted position in Fig. 2 in the position shown in dashed lines. · This allows all water in the measuring container 60 through the line 70 flow into the sump and the sterilization chamber. The heating device in the sterilization chamber then Water evaporates. A return flow of the water vapor through the line 70 into the measuring container is prevented by the check valve 82 and the location of the solenoid valve 80 prevents. At the end of the sterilization cycle, done in the manner mentioned with the help of a no The sensor shown is determined, the solenoid valve 80

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actuated and moved into the position shown in solid lines. Steam can now exit the sterilization chamber through part of line 70, line 72, and ejector 74. Because of the steam flow through the ejector 74, water is sucked out of the storage container 64 via the suction line 76. That with the Water mixed with steam serves to condense it, so that only water flows through the outlet 78 into the measuring container 60.

Since only a small amount of the discharged steam is lost, practically all of the steam is condensed and returned to the measuring container 60. Together with the amount of water that is sucked up from the storage container 64, this leads to an overflow of the measuring container, so that the overflowing water reaches the storage container 64 via the wall 66. Therefore, at the end of the sterilization cycle, the measuring container 60 is automatically filled and contains a measured amount of water for the next sterilization cycle.

Table-top sterilizers are usually designed to that the same amount of water is required for each Sterxlisxzer cycle. Therefore, the reservoir 60 can be designed so that it contains the optimal amount of water, so that there is normally no need to change a device of the volume of the measuring container 60 to be provided. However, it is also possible to provide a variable volume of the measuring container, for example, by providing means to decrease or increase the height of wall 66, or by Blocks are introduced into the measuring container to reduce the volume of water.

The invention therefore provides a table-top sterilizer which has a device for automatic refilling the sterilization chamber with a predetermined amount of water at the beginning of each sterilization cycle. With the described Further modifications are possible, for example the separate ones shown in FIGS.

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th components are preferably housed in a single housing will. Furthermore, the line 22 and the throttle device 28 in FIG. 1 do not have to be in direct connection with the cylinder 24 stand because the line 22 and the throttle device 28 'directly with the line 30 between the cylinder and the solenoid valve 32 can be provided. With this arrangement, only part of the steam discharged from the sterilization chamber 12 is used is introduced into the cylinder 24 to cause the return stroke of the piston and heat the cylinder.

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Claims (11)

Claims 1. Tabletop sterxer with a water reservoir and a Heating device for evaporating water in the sterilization chamber, characterized in that a device for automatically supplying a predetermined amount of water is provided from the storage container into the sterilization chamber, consisting of a measuring container (24; 60) for water, the has a predetermined volume and is in communication with the storage container (20; 64) and the sterilization chamber (12; 62), from which measuring container practically all water into the sterilization chamber arrives at the beginning of a sterilization cycle, a line connecting the measuring container to the sterilization chamber (30; 70) with a valve (32; 8O), which valve is opened at the start of a sterilization cycle, a backflow device, to return water vapor at the end of a sterilization cycle from the sterilization chamber through the measuring container to the storage container, to at least partially fill the measuring container with condensed steam, as well as from a refilling device to To return water from the storage container to the measuring container at the end of a sterilization cycle and the measuring container is practical to fill completely. 2. Tischsterxsxerapparat according to claim 1, characterized in that that an ejector (74) is provided as a backflow device, the inlet of which is in connection with the The sterilization chamber is located, the outlet (78) of which is above the measuring container (60) and the suction line (76) of which extends into the storage container (64) extends so that when the steam is dispensed by the ejector, water is sucked out of the storage container and mixed with the steam is, and with the condensed steam and the water, the measuring container is filled to overflow, and that one overflows device (66) between the measuring container (60) and the storage container (64) is provided. 3Q988W1367 3. Table sterilizer according to claim 2, characterized in that the storage container (64) and the .Meßbehälters (60) are arranged in a single vessel, and that a wall (66) separates the two containers from one another. 4. Tischsterxlisierapparat according to claim 2, characterized g e label Ichnet that the measuring container (60) is arranged in comparison to the sterilization chamber (62) that the Water flows into the sterilization chamber due to gravity. 5. Tischsterxlisierapparat according to claim 1, characterized g e indicates, that the measuring container has a cylinder chamber (24) is that a piston (38) is arranged in the chamber (24), and that a drive device (40) is provided for driving the piston is to push virtually all of the water in the cylinder into the sterilization chamber. 6. Table sterilizing apparatus according to claim 5, characterized in that that the vapor discharge device is a line (30, 30B) with a check valve (34B) between the Steril isierkammer (12) and the cylinder (24) so that through the in the chamber (24) occurring vapor pressure the return stroke of the piston (3 8) is carried out. 7. Table sterilizing apparatus according to claim 6, characterized in that that the refilling device is a line (22) which connects the storage container (20) with the cylinder (24) connects that a throttle device (28) is provided in this line so that the cylinder is refilled by condensation of the steam therein, creating a negative pressure, to suck water through the pipe from the reservoir into the cylinder. 8. Tischsterxlisierapparat according to claim 1, characterized by combining the features that the measuring container 3 0 9 8 8 UI 1 3 6 7 has a known volume and is arranged in such a way that the water flows into the sterilization chamber by gravity can that a line connects the sterilization chamber with the container, that a valve in the line at the beginning of a sterilization cycle is actuatable to allow a flow of water from the container into the sterilization chamber, which valve at the end of the sterilization cycle is closed that a steam release device is operable at the end of a sterilization cycle to release virtually all steam from the chamber and that steam with water to mix, which is withdrawn from the reservoir to condense the steam, which device then the mixture out Water and condensed steam returns to the measuring container and completely fills the measuring container, and that an overflow device is provided between the measuring container and the storage container. 9. Table sterilizer according to claim 8, characterized in that that the vapor discharge device is an ejector is, its inlet in connection with the sterilization chamber stands, whose outlet is arranged above the measuring container, and whose suction line extends into the storage container. 10. table sterilizer according to claim 8, characterized g e indicates that the chamber and the reservoir are two sections of a vessel, and that the overflow device is a partition between the two sections. 11. Table sterilizer according to claim 1, characterized by the combination of the features that a cylinder chamber in the line between the storage container and the sterilization chamber is provided which divides the conduit into two parts and communicates with each part that in the cylinder chamber a piston is arranged, .that a drive device for the piston is provided so that practical during a piston stroke 0988 /, / 1 3 B 7 ? 333755 all water in the cylinder chamber is displaced into the sterilization chamber is / that a valve is arranged in the part of the line between the cylinder chamber and the Sterilisierkainmer that a Control device for the piston drive device and the valve is provided through which these are actuated at the beginning of a sterilization cycle, so that the water in the cylinder chamber is pressed into the sterilization chamber, which control device actuates the valve at the end of the sterilization cycle, thus at least some of the steam in the sterilization chamber can be released into the cylinder chamber in order to effect the return stroke of the piston, and that the steam in the cylinder chamber then condenses so that A negative pressure is generated in the cylinder chamber and water from the reservoir through the line for refilling the cylinder chamber is sucked in. 309884/1367 Blank page