Abstract:
A dispensing apparatus for fluid media is disclosed which comprises a dosing piston movably guided within a dosing cylinder and a subsequent rotary valve, wherein the cleaning and/or sterilization of the parts coming into contact with the filling product can be performed without removing these parts. By means of a particular disposition and embodiment of the dosing piston, the rotary valve and the dosing cylinder, it is possible to make the dosing piston and rotary valve accessible rapidly and simply.

Description:
BACKGROUND OF THE INVENTION 
     In a known filling apparatus for fluid media (German Offenlegungsschrift No. 23 08 689), there is disclosed a dosing piston which is movable into an extended portion of the dosing cylinder where the outer surface of said piston is exposed. In this extended portion of the cylinder, the dosing piston becomes accessible for cleansing through a rinsing or cleaning medium. The rotary valve provided at the upper part of the dosing cylinder, however, cannot be made accessible in this known apparatus; thus it can neither be completely cleaned, nor, more importantly, can it be sterilized. For applications within the pharmaceutical industry in particular, such a filling apparatus, which cannot be rendered sterile, cannot be used. To meet this requirement for sterility, therefore, an apparatus is needed in which both the dosing piston and the rotary valve are fully accessible for cleansing via an enveloping fluid comprising a rinsing, cleaning, and/or sterilizing medium. 
     OBJECT AND SUMMARY OF THE INVENTION 
     It is the principal object of the invention disclosed herein to provide an apparatus which has the advantage over the prior art, that as a result of the particular coaxial disposition of dosing piston and rotary valve, both the dosing piston and the rotary valve can be made fully accessible to a cleansing medium by means of a simple displacement of the dosing cylinder. This arrangement allows a very simple and certain cleaning or sterilization of the piston and valve which come into contact with the dispensed end product. 
     Another object of the invention is to obviate the need for an additional pump clamping means, in the apparatus according to the invention, by providing a dosing cylinder which is guided, in movement up and down, within a cylinder which is secured, preferably to the machine frame. 
     A further object of the invention is to provide an apparatus which, in the disassembled state as well, offers the capability for cleaning due to the fact that the cylinder bore extends entirely through the cylinder. 
     A still further object is that, advantageously, this dispensing apparatus can also be used for end products which crystallize out, without additional liquid, so that there is no danger of intermixing. 
     The characteristics recited in the dependent claims provide advantageous further embodiments and improvements of the dispenser arrangement recited in the main claim. 
     The invention will be better understood, as well as further objects and advantages thereof become more apparent, from the ensuing detailed description of a preferred embodiment taken in conjunction with the drawing. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     FIG. 1 shows a dispensing apparatus following the invention in working position, that is, in the fluid induction phase; and 
     FIG. 2 shows the dispenser apparatus of FIG. 1 in the cleaning or sterilization position. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to FIG. 1, there is shown a dispenser apparatus in accordance with the invention which comprises a cylinder 1, which is positively mounted, for example, upon a machine frame 2, and a dosing cylinder 3 guided for movement upwardly and downwardly within this cylinder 1 by known means (not shown). Within this dosing cylinder 3, a dosing piston 4 is provided which is connected, via a piston rod 5 and a coupler 6, with a rod 7, which rod is also movable up and down by other known means (not shown). In order to seal the chamber 8 from contamination by outside air, the chamber is filled with protective gas during the dispensing operation, which gas is retained by a seal 10 in the base 9 of the cylinder 1. 
     A rotary valve 11 is disposed above the dosing piston 4 within the dosing cylinder 3. This rotary valve 11 is connected to an actuation shaft 12 via an attachment 13 and a coupler 14. The actuation shaft 12 is made to rotate during operation by known means, which are not shown. The dosing cylinder 3 is provided with an inlet channel 15 and an outlet channel 16, respectively, for supply and delivery of the product to be dispensed. Inlet channel 15 and outlet channel 16 are provided in opposed relation to one another. In opposed spaced relation, inlet and outlet channels 17 and 18, respectively, are provided for admitting and discharging both protective gas and the cleansing or sterilization fluid; to achieve the same purpose, the cylinder 1 is provided in opposed spaced relation with inlet and outlet channels 19 and 20, respectively. 
     FIG. 1 shows, in particular, that the rotary valve 11 is guided within a cylindrical bore 21 of the dosing cylinder 3. This cylindrical bore 21 has an adjacent chamber portion 22 of enlarged diameter which, as FIG. 2 shows, provides accessibility ot the rotary valve 11 when the valve is moved from a first downward position to a second upward position. Above the chamber portion 22 there is a cylindrical bore 23, whose diameter corresponds to that of the cylindrical bore 21. The cylindrical bore 23 is provided with a seal 24, which is secured on the attachment 13 of the rotary valve 11. 
     The mode of operation of the dispenser apparatus will be made clear from the following description: 
     In FIG. 1, the dispenser apparatus is shown in a first working position, that is, in the induction phase for the fluid to be dosed and dispensed. This fluid is supplied via the inlet channel 15; during this supply period the dosing piston 4 is moved downward to create a volume in accordance with the quantity of fluid which is desired to be dosed. As indicated at reference numeral 25, the rotary valve during supply is in the position shown which opens the inlet channel 15 so that the fluid can enter into the chamber 21. Upon dosing piston 4 reaching the desired downward limit of travel, the rotary valve is turned 180° so that the outlet channel 16 is in communication with the chamber 21. Thereupon, the upward movement of the dosing piston 4 begins and the fluid contained in the cylinder is dispensed via the outlet channel 16 into a vessel, not shown, which is desired to be filled. During this dosing and filling process, a protective gas, such as sterile air, is provided both in the chamber 8 located below the dosing piston 4 and in the chamber 22 located above the rotary valve 11. 
     In FIG. 2, the cleansing or sterilization position of the dispenser apparatus according to the invention is shown. As shown, the dosing cylinder 3 has been moved downward within the cylinder 1, so that both the dosing piston 4 and the rotary valve 11 are rendered immersible to a cleansing fluid. The upper bore 23 is now closed off by the seal 24. At this time a cleansing or sterilizing medium can be supplied via the inlet channel 18, which is supplied via the channel 17 and a line 26, shown in broken lines, to the inlet channel 19 and thus to the chamber 8 and can exit again via the outlet channel 20. The inlet and outlet channels 15 and 16, respectively, for the dispenser product are made to remain closed during this cleaning or sterilization procedure in known manner. 
     In order to cleanse and sterilize the supply and delivery lines (not shown) attached to the inlet and outlet channels 15 and 16, a cleaning or sterilizing medium can be supplied to the inlet channel 15 and can be drawn off via the outlet channel 16. During this procedure, the cleansing fluid inlet and outlet channels 18 and 20 are closed. These two cleansing and sterilization phases may be performed in alternation. 
     As a result of the coaxial disposition of the dosing piston 4 and the rotary valve 11, on the one hand, and the displaceable disposition of the dosing cylinder 3, on the other hand, there is achieved, as clearly shown in FIG. 2, a very simple, effective, and certain manner for cleaning those parts which come into contact with the dispenser product. In addition, the apparatus following the preferred embodiment allows a very simple disassembly of the entire dispenser apparatus. 
     The foregoing description relates to a preferred embodiment of the invention; however, the apparatus comprehends that other embodiments and variants thereof are possible within the spirit and scope of the invention, which is defined by the appended claims.