High speed aseptic filling machine

Abstract: A filling head apparatus for filling a container in sterile conditions. The filling head comprises a regulating valve (320) displaceable in three positions: open position, closed position, and displacement position. The inner wall of the spout (1145) of the container is cleaned by a pushing cylinder (1140) of the regulating valve traveling from the closed position to the displacement position. In addition, the filling head can freely move in respect to a sterile filling chamber encompassing the filling tip (770) of the filling head. Furthermore, the filling head of the present invention comprises a diversion path to minimize the "water hammer" effect.

Description: Many liquid and semi-liquid products are packaged into large containers for storage and distribution to repackagers, commercial uses and other users of large quantities of the product. Many of these products, particularly food products, deteriorate rapidly when exposed to oxygen. Additionally, food products must be protected against possible contamination from bacteria. Therefore, these products are often placed in large (e.g. one to six gallon) containers made of plastic or similar material and having one spout through which the container is filled and from which the product is dispensed from the container. These plastic containers are advantageous in that as the product is dispensed from the container, the container collapses around the remaining material so that no air enters the container. With container of a fixed shape or internal volume, air must enter the container to fill the volume left in the container as the product is dispensed. This air contains oxygen and frequently carries harmful bacteria. These containers typically have a rigid or semirigid plastic spout through which the product passes to enter or leave the container. In addition, care must be taken in packaging food products into the containers that no bacteria could enter the container that would create a potential health risk to the consumer of the food product. To ensure the sterility, it is disclosed in U.S. patent no. 4,458,734 issued to Scholle et al. that the container is filled inside a filling chamber that maintains a sterile atmosphere around the spout of the container. The filling chamber is sterilized and is filled with a sterile gas, with the gas maintained in the chamber at a positive pressure with respect to the outside environment. The positive pressure of the gas ensures that no air from outside the chamber enters the chamber, as the flow through any opening in the chamber walls is from the higher pressure interior to the lower pressure exterior. A filling head is provided inside the chamber for filling the container with the fluid. An opening is then provided in the bottom of this chamber that is large enough to receive the spout of one of the plastic container food containers. Once the spout is placed in the opening, it is brought into contact with the filling head and the fluid is dispensed into the container. One of the main deficiencies of the Scholle's invention is the lack of ability to clean the spout of the container. The spout of the container contributes to the contamination in two ways. First, after filling the fluid into the container, some residual fluid is stuck onto the inner wall of the spout opening of the container which then causes contamination to the fluid contained in the container. The other source of contamination is that bacteria stuck onto the inner surface of the spout is brought into the filling chamber when the spout of the container is lifted into the filling chamber. Therefore, in order to prolong the shelf life of the packaged products, a new method or apparatus is needed to reduce the two abovementioned contaminations. In U.S. patent 4,893,659 issued to Loeliger, it is disclosed a filling head apparatus having valves at the tip of the head for regulating flow of a sterilizing medium and regulating flow of a fluid to be filled in a container to a filling head space. The Loeliger disclosure is directed to the resterilization of the spout opening of the container after filling and discloses a filling head combined with a sterilizing medium dispersion valve at the tip of the head to sterilize the spout of the container. However, the Loeliger's design specifically requires a steam outlet passage connected to the side of the tip of the filling head for the escape of the steam introduced. Therefore, for the Loeliger's system, an extra pipe is needed to connect to the tip of the filling head for the draining of the escaping steam. Because the sterile chamber is very small and the Loeliger disclosure requires this extra steam outlet connected to the tip of the filling head, the Loeliger's disclosure is not practical to be implemented in a sterile chamber. Therefore, a new design on the filling head is needed for the sterilization of the spout of the container. US Patent No: 4,446,674 to Junji Inada (on which document the preamble of claim 1 is based) discloses a filling valve assembly and a cap remover assembly mounted side by side in a germfree chamber over a weighing platform upon which a spouted bag is placed for filling. During the filling operation the spout is held against a filling head of the valve assembly. Filling is initially at a high rate to an extent slightly less than the prescribed weight, and then with the spout separated and held at a slight distance from the filling head, at a reduced rate to the prescribed weight. The present invention is directed at a filling head apparatus for filling a container having a spout opening for filling, comprising a filling head housing defining a filling head chamber, and having a filling head with a fluid inlet for receiving from a source fluid to be filled in the container and a filling tip for delivering the fluid to the container. According to the invention a regulating valve is disposed within the filling head housing for regulating flow of fluid from the filling head chamber through the filling tip, which regulating valve is displaceable within the filling head housing in at least three positions comprising a first open position, a second closed position, and a third displacement position. When the regulating valve is in its open position, fluid is allowed to flow through the filling tip, and when the regulating valve is in its closed position or its displacement position, flow of fluid through the filling tip is blocked, the regulating valve functioning as a pushing cylinder as it moves from its closed position to its displacement position, at which it protrudes from the filling tip for engagement in the spout opening in a container, the regulating valvedefining an escape path for residual fluid during such movement. An inlet passage may be defined in the regulating valve for supplying a cleaning gas to clean the inside of the spout opening in a container. The escape path in the regulating valve may provide an outlet for the cleaning gas. Typically, the inlet passage and the outlet for the cleaning gas are.separated concentric passages inside the regulating valve. Apparatus according to the invention is particularly suitable for aseptically filling a container, and can be used in a high speed sterile filling system. Further, it may be adapted to clean the spout opening of the container, and to minimize or eliminate the water hammer effect. It is a further object of the present invention to provide a design of the filling head and aseptic chamber assembly which reduces mechanical movement of various components. In a high speed sterile filling system using filling head apparatus of the invention the filling head may have a pushing cylinder located at the tip of a regulating valve disposed inside the filling head for cleaning the inner wall of a spout opening of the container after each filling. The invention will now be described by way of example, and with reference to the accompanying drawings wherein: Figure 1 illustrates a schematic diagram of the aseptic filling system of the present invention. Figure 2 illustrates a perspective view of a filling portion of a preferred embodiment. Figure 3 illustrates a cross section diagram of the filling portion of a preferred embodiment. Figure 4 illustrates a perspective view of a filling head connecting with a filling chamber. Figure 5 illustrates the raised position of the filling head. Figure 6 illustrates the downward position of the filling head. Figure 7 illustrates a cross section diagram of a preferred embodiment of the filling head, filling chamber and container. Figure 8 illustrates a beginning position of the filling head. Figure 9 illustrates that the spout of the container is lifted into the filling chamber. Figure 10 illustrates that the filling head is lowered for filling. Figure 11 illustrates that the cap of the container is replaced after filling. Figure 12 illustrates that the filled container is lowered after filling. Figure 13 illustrates a cross section diagram of the filling head of another preferred embodiment. Figure 14 illustrates the closed position of the regulating valve. Figure 15 illustrates the displacement position of the regulative valve. Figure 16 illustrates a detail cross section diagram of the filling tip. Figure 17 illustrates the detached position of the filling head. Figure 18 illustrates a schematic diagram of the filling system. Figure 19 illustrates a cross section diagram of the filling head of another embodiment. Figure 20 illustrates the open position of the filling head. Figure 21 illustrates the closed position of the filling head. Figure 22 illustrates the displacement position of the filling head. Figure 1 provides a schematic diagram of the aseptic filling system of the present invention. The preferred embodiment of the aseptic filling system comprises a filling portion 110 and a transportation portion 120. The filling portion 110 comprises mechanisms for positioning the container for filling, an aseptic filling chamber for maintaining a sterile environment during filling, a decapper/capper for decapping and recapping the container before and after filling, and a specially designed filling head for filling the container and for subsequent cleaning of the spout opening of the container after filling. The transportation portion 120 of the filling system comprises a positioning mechanism to position the empty container to the filling portion 110 for filling, and a conveyor belt 150 for transporting the container out of the filling portion 110. The transportation portion 120 has an entry port 160, through which the empty container is fed, a filling area 170 where the container is filled, and a dispense port 180, through which the filled container is dispensed. The container, which is to be filled with a fluid by the apparatus of the present invention, is preferably constructed of a flexible material, such as plastic. The container has a filling spout, preferably sealed by a removable cap. The filling spout of the container is used hereinafter as the fluid conduits with which the apparatus is used. Different sizes of the containers can be accommodated by the present invention. In the preferred embodiment, one to six gallon containers are used. In a preferred embodiment, the present invention utilizes premanufactured containers, connected in a continuous web. The containers have been prepackaged in a sealed overwrap container 190 and presterilized therein. The sealed overwrap container 190, comprises, for example a corrugated paper board, is positioned adjacent to the entry port 160. An operator manually grasps the end of the continuous web, pulls it through the opening, and operably connects it to the feed means of the apparatus, for example, by clipping the leading edge of this continuous web to the trailing edge of the preceding continuous web of containers. Figure 1 illustrates that when the container is positioned below the filling chamber 140, the spout of the container is then raised into the filling chamber 140. In one embodiment of the present invention, a decapper/capper 560 (not shown in Figure 1) is located inside the filling chamber 140 for (1) removing the cap covering the spout opening of the container before each filling, and (2) subsequently recapping the container after the filling is completed. In the preferred embodiment, the decapping, filling and recapping are all performed inside the filling chamber 140 so that no contamination is introduced into the container. After the container is completely filled, the container is advanced out of the filling portion 110 by the conveyor belt 150 to the dispense port 180. A severing bar disconnects adjacent filled containers at perforations in the container web between adjacent containers, so that the containers may be deposited into protective enclosures, such as corrugated paper board boxes. Figure 2 illustrates a perspective view of the filling portion 110 of a preferred embodiment of the present invention. The filling portion 110 of the present invention includes a sterile filling chamber 140, defined by a top plate, a bottom plate and side walls. A filling head 220 having a filling tip (not shown) enters the filling chamber 140 through an opening in the top plate and ends with its filling tip inside the filling chamber 140. The filling head 220 is connected with a filling tube which conducts a fluid, such as a liquid or viscous material, from a source to the filling head 220 and then fills the container through the tip of the filling head 220. In addition, as shown in Figure 2, the present invention also comprises a spout gripper 230 that holds and lifts the spout of the container into the filling chamber 140 through an opening on the bottom plate of the filling chamber 140. In the preferred embodiment of the present invention, the gripper 230 comprises a pair of handling plates shaped with the curvature of the spout. The spout of the container is gripped by the movements of the pair of handling plates. In addition, the spout gripper 230 also travels in a vertical motion perpendicular to the grabbing movements to lift the spout of the container into the filling chamber 140. In a preferred embodiment, a clamp pad 990 is positioned under the filling head 220 to facilitate the cleaning of the spout opening after filling. After the completion of filling, the clamp pad 990 located directly below the lower edge of the spout opening raises and presses the bottom of the container against the lower edge of the spout opening. By pressing the bottom of the container against the bottom edge of the spout, the interior of the container is isolated from the spout opening during the subsequent spout cleaning process. An important aspect of the present invention is the design of the filling chamber 140 of the aseptic filling system. Figure 3 shows the detail of the filling portion 110 comprising a filling chamber 140 which is maintained to be sterile at all time during filling by maintaining positive pressure of sterile gases/fluid or steam inside the chamber, a filling head 220 for delivering fluid to the container, a cap decapper/capper 560 located inside the filling chamber 140 for removing and reinstalling the caps covering the spout of the container, a spout gripper 230 for grabbing and lifting the spout of the container into and out of the filling chamber 140, and a clamp pad 990 for facilitate the cleaning of the spout opening. In the preferred embodiment as shown in Figure 3. The filling head 220 is pivotally connected to the filling chamber 140 to allow vertical movement of the filling head 220 in respect to the filling chamber 140. A rolling diaphragm seal 330 is positioned between the filling head 220 and the opening 340 located in the top plate of the filling chamber 140 for sealing the circumferential spacing between the filling head 220 and the top plate to prevent any contaminations from entering the sterile filling chamber 140. The rolling diaphragm seal 330 is preferably made of elastic plastics so that the filling head 220 is allowed to move freely in a vertical motion to engage and disengage with the spout opening of the container without allowing any contaminations to enter the sterile filling chamber 140. Figures 4, 5, and 6 show different views of the preferred embodiment of the filling head assemblies of the present invention. As shown in the figures, the filling head 220 is connected with the filling chamber 140 by a hinge 410 so that the filling head 220 can be moved freely in a vertical motion in respect to the aseptic filling chamber 140. By allowing the filling head 220 to move freely in respect to the aseptic filling chamber 140, the entire filling system can be simplified because less components are needed to move during each filling and the filling chamber 140 can stay stationary during each filling. As illustrated in Figure 5, the filling head 220 of the present invention is in an upward position. The filling head 220 is raised pivotally upward to allow the spout of the container to enter into the filling chamber 140, and allow the decapper 560 to decap the spout of the container. Figure 6 shows that the filling head 220 is in a downward position. In this position, the filling head 220 is pivotally traveled downward so that the filling tip of the filling head 220 presses against the upper edge of the spout of the container to prevent any contamination from entering the container during the filling. It should be emphasized that, as shown in Figures 4, 5, and 6, only the filling head 220 is moved during each filling. The filling chamber 140, decapper/capper, and other mechanisms remain in the same position during each filling. This arrangement greatly reduces the movement of each component in the filling system, which thereby allows faster filling for each container. The detail operations of the filling head 220 and the filling chamber 140 are explained in detail below. Figure 7 shows, in the preferred embodiment, that when a container 510 is positioned under the filling chamber 140, the gripper 230 grabs the spout 540 of the container 510 and lifts the spout 540 into the filling chamber 140 so that the spout is engaged with the filling head 220. The gripper 230 comprises a pair of handling plates shaped to the curvature of the spout 540 for securely grabbing the spout 540. Both the grabbing motion and the vertical lifting motion can be actuated by high speed heavy duty air cylinders. In a preferred embodiment that the spout 540 of the container 510 is capped, once the spout 540 of the container 510 is positioned inside the filling chamber 140 by the gripper 230, a decapper/capper 560 located inside the filling chamber 140 decaps the spout 540 and exposes the spout opening for filling. In the preferred embodiment of shown in Figure 7, a sterile air inlet 570 is provided to direct air or other sterile gas to the filling chamber 140 to create a positive pressure inside the filling chamber 140. The gas used for sterilizing can be steam, or a sterile gas that contains no oxygen to maximize the shelf life of the product being packaged into the container 510. The gas is supplied to the chamber in a sufficient quantity that the pressure inside the chamber is greater than that of the environment outside the chamber. This positive pressure ensures that if there are any leaks around filling tube or in the holes on the top and bottom plates, the gas from inside the chamber will escape to the outside environment. This prevents the air from outside the chamber, with the bacteria it may contain, from entering the filling chamber 140, and preserves the sterility of the chamber. In a preferred embodiment of the present invention, a sanitizing fluid spray jet 580 is placed inside the filling chamber 140 for providing sanitizing fluid to the interior of the filling chamber 140. By pointing the spray jet at the filling tip 770 of the filling head 220, the filling head 220 can be cleaned both before and after each filling. Figure 8 shows a beginning position of the filling head 220 when an empty container 510 is positioned under the filling chamber 140. In this position, the filling head 220 is raised to allow the spout 540 of the container 510 to enter the filling chamber 140 through the opening in the lower plate. Figure 9 shows that, after the gripper 230 lifts the spout 540 of the container 510 into the filling chamber 140, the cap 545 of the container 510 is then removed by the decapper/capper 560 located inside the filling chamber 140. In addition, the spout 540 is aligned by the gripper 230 in a position below the filling head 220 so that the spout opening is directly under the filling tip 770. Figure 10 shows that, after the cap of the container 510 is removed, the filling head 220 is lowered and the lower edge of the filling tip 770 is pressed against the upper edge of the spout 540 of the container 510. The fluid is then delivered into the container 510 by the filling head 220 through the filling tip 770 and the spout 540 of the container 510. In a preferred embodiment, the filling speed is about 14 to 16 containers per minute on 2.5 gallon containers. The flow rate is about 100 gallon per minute, and the pressure at the inlet is about 30 to 35 psi. Figure 11 shows that the filling head 220 is raised and the cap is replaced onto the spout 540 of the container 510 for sealing after the filling is completed. Note that in this position, the clamp pad 990 is pushed upwardly so that the bottom of the container 510 presses against the lower edge of the spout 540 of the container 510. By pressing the bottom of the container 510 onto the lower edge of the spout 540, no residual fluid and contaminations can enter the interior of the container 510 during the process of cleaning and recapping. Figure 12 shows that, after the cap is placed back onto the spout 540 of the container 510, the container 510 filled with fluid is then lowered onto the conveyor belt 150 for transporting to the dispense port 180 for packing. In this position, various components in the filling portion 110 of the filling system including the filling head 220 and the clamp are returned to the beginning positions in preparation of another empty container 510. Another aspect of the present invention is the cleaning functions of the filling head 220. Figure 13 show a preferred embodiment of the filling head 220 of the present invention. The filling head 220 comprises a filling head housing 1105 having a fluid inlet portion and a filling tip 770. The fluid inlet portion is for receiving fluid to be filled into the container 510, whereas the filling tip 770 is for engaging with the spout 540 of the container 510 to transfer the fluid to the container 510. In the preferred embodiment, the filling head 220 further comprises a regulating valve 320 encompassed by the filling head housing 1105. The regulating valve 320 is designed for coaxial movement and is vertically displaceable inside the housing 1105. As shown in Figure 13, a fluid passage 1130 is formed circumferentially between the regulating valve 320 and the narrowing inner wall 1134 of the housing 1105. By moving the regulating valve 320 along the longitudinal axis of the housing, the flow of the fluid from the filling head 220 into the container 510 can be regulated. For example, the fluid is allowed to flow into the container 510 through the filling tip 770 when the regulating valve 320 is in the upward position. The fluid flowing into the container 510 is stopped when the regulating valve 320 is moved downward to block the fluid passage 1130. The regulating valve 320 as shown in Figure 13 further comprises a pushing cylinder 1140 at one end. In the preferred embodiment as shown, the pushing cylinder 1140 is designed to travel beyond the top end of the filling tip 770 and protrude inside the spout opening 1145 of the container 510. When the container 510 is filled, the extended pushing cylinder 1140 of the regulating valve 320 can move beyond the filling tip 770 and into the spout opening 1145 to remove the fluid stuck inside the spout opening 1145. By extending the pushing cylinder 1140 into the spout opening 1145, the residual fluid located inside the spout opening 1145 can be squeezed out of the spout opening 1145 and into the container 510. Figure 13 shows that, after the container 510 is positioned below the filling chamber 140, the spout 540 is lifted into the opening to the filling chamber 140 by the gripper 230 (gripper 230 not shown in Figure 3). The filling tip 770 of the filling head 220 is then lowered to engage with the top edge of the spout 540. Note that during the entire filling operation, the regulating valve 320 of the filling head 220 is in an upward open position which allows a fluid passage 1130 to be formed between the inner wall 1135 of the filling head housing 1105 and the tip of the elongated regulating valve 320 to allow the fluid flowing into the container 510 though the filling head housing 1105. It should also be pointed out, during the filling the clamp pad 990 is in the downward position to allow the fluid to enter the container 510. Figure 14 shows that when the system detects a sufficient amount of liquid is transferred into the container 510, the fluid passage 1130 is shut off to prevent any further fluid in entering the container 510. In this position, the regulating valve 320 is lowered to block the fluid passage 1130. In the preferred embodiment as shown, the diameter of the regulating valve 320 is sized to be approximately equal to the inner diameter of the narrowing portion of the filling head housing 1105 so that the fluid passage 1130 is completely sealed when the regulating valve 320 is in the downward position. Figure 15 shows the filling head 220 and the spout 540 in a "displacement position." The diameter of the pushing cylinder 1140 is designed to be substantially equal to the inner diameter of the spout opening 1145 so that when the pushing cylinder 1140 travels from the closed position to this displacement position, the circumferential edge of the pushing cylinder 1140 squeezes against the inner wall of the spout opening 1145 and thereby removes any residual stuck onto the inner wall of the spout opening 1145. Figure 15 further shows a residual escape path 1150 located inside the regulating valve 320. When the pushing cylinder 1140 is forced downward into the spout opening 1145, the residual fluid is then forced out of the spout opening 1145 into the container 510. It should be noted that the clamp pad 990 is raised to the upward position for sealing the interior of the container 510 from the spout opening after the pushing cylinder 1140 travels from the closed position to the displacement position. By maintaining the clamp pad 990 in the upward position during the spout cleaning process, the bottom of the container 510 is pressed against the bottom edge of the spout opening 1145 to prevent any residual fluid from entering the container 510. In the preferred embodiment of the present invention as shown in Figures 13-15 , a residual escape path 1150 is located inside the pushing cylinder 1140 to assist residual fluid or air to escape from the spout opening 1145. Furthermore, in another preferred embodiment of the present invention (not shown), the residual escape path 1150 is connected to a siphon pump to facilitate the escape of the residual out of the spout opening 1145. Figure 16 shows a preferred embodiment of the present invention. In this preferred embodiment, a cleaning gas such as nitrogen or steam is delivered from the pushing cylinder 1140 to the inner wall of the spout opening 1145 for cleaning the inner wall of the spout opening 1145 when the pushing cylinder 1140 travels from the closed position to the displacement position. The sterile gas is delivered through a gas passage 1170 inside the regulating valve 320 and is injected onto the inner wall of the spout opening 1145 from openings 1180 located at the tip of the pushing cylinder 1140 as shown in the figure. The steam is then escaped from the spout opening 1145 using the inner residual escape path 1150. In a preferred embodiment, this step of sterilization of the spout opening 1145 can be carried out with saturated steam at a temperature in the range from 140 to 150 C, in which the head space is sterilized with steam arriving at a rate of 50 to 450 m/sec at a temperature 120 to 150 C. The arrival of steam at the rate mentioned above is achieved through an expansion of pressure of the order of 2 to 3 atmospheres. Figure 17 shows that when the filling head 220 is disengaged with the spout 540 of the container 510. Because of the subsequent cleaning of the spout opening 1145 and the tight fitting of the pushing cylinder 1140 with the spout opening 1145, there is no dripping of the fluid from the filling tip 770. Another aspect of the present invention is the novel design of the filling head 220 being able to eliminate or minimize the "water hammer" effect caused by the shutting off of the flow of the fluid between each filling. It is known that at a quick shut off of certain valve of a fluid flowing in a pipe, a pressure shock can occur that exposes the pipe system to strong loads as well as causing noise. This water hammer effect shortens the life expectancy of the pipe used in the filling system, and also causes tremendous noise between each filling. The present invention provides a filling head 220 with a diversion valve design that can eliminate, or at least minimize, this effect. Figure 18 shows a schematic diagram of a conventional pumping system. In the conventional filling system as shown in Figure 18, the fluid is supplied to the filling head 220 through an fluid inlet 1310 connected to an accumulator 1210. The fluid level in the accumulator 1210 is kept to a predetermined level by adjusting the pressure inside the accumulator 1210. A pump 1220 is employed to pump the fluid to the filling head 220 through the fluid inlet 1310. In addition, a meter 1230 is connected in series between the accumulator 1210 and the filling head 220 for measuring the amount of fluid flowing into the filling head 220. When a predetermined amount of fluid is flowed into the filling head 220, the pump is stopped to prevent fluid from entering the filling head 220. Figure 19 shows a filling head 220 of a preferred embodiment of the present invention. The filling head 220 comprises a fluid inlet portion 1310 and a filling tip 770. In addition, the filling head 220 provides a return path 1330 to divert the flow of the fluid when a predetermined amount of fluid is filled to the container 510. The detail operations of the present invention are shown in Figures 20, 21, and 22. Figure 20 shows the filling head 220 in an open position. In this position, the fluid is allowed to flow from the fluid inlet portion 1310 to the containers through the filling tip 770 and the spout opening 1145 following the path A as shown in Figure 20. The fluid is pumped into the filling chamber 140 through the inlet portion 1310, then flows into the container 510 through the outlet portion and the spout opening 1145 of the container 510. When the meter detects the predetermined amount of fluid has been delivered to the container 510, the valve is moved from the open position to a closed position as illustrated in Figure 21. During the shutting off the flow of liquid to the container 510, a liquid release passage as indicated in the figure is opened for the liquid to flow back to the accumulator 1210 through the return portion 1330. As shown in Figure 21, the elongated regulating valve 320 is specifically designed to allow the liquid to flow into the return portion 1330 during the shutting off of the regulating valve 320. Instead of instantly shutting off the fluid pump when the predetermined amount of fluid has been filled into the container 510, the filling head 220 of the present invention diverts the flow of the fluid to a return path 1330 as indicated in Figure 21. By having the fluid return path 1330 to divert the flow of liquid during the shutting off of the fluid into the container 510, the water hammer effect caused by the instantaneously shutting off of the fluid flow can be eliminated, or at least minimized. Figure 22 shows the position of the pushing cylinder 1140 when the valve has traveled to the displacement position. In the displacement position, the entire pushing cylinder 1140 is protruded into the spout opening 1145 of the container 510. The return path B is totally open so that the fluid is entirely flowing from the inlet portion 1310 to the return portion. In another preferred embodiment, there is a shut off valve in the fluid return path 1330 that can be slowly shut off to prevent the water hammer effect. In another further preferred embodiment, the amount of liquid filled to the container 510 is controlled by the regulating valve 320 alone so that no fluid shut off valve is needed. In this preferred embodiment, the flow of the fluid into the container 510 through the filling tip 770 is controlled by the regulating valve 320 alone. During filling, the valve is in the upward position and the fluid flows into the container 510 following the path C. When the predetermined amount is reached, the valve is then lowered so that the fluid flows through the return path 1330 back to the accumulator 1210. Therefore, the flow of the fluid remains uninterrupted and no shut off valve is needed.

Claims: A filling head apparatus for filling a container (510) having a spout opening (540) for filling, comprising a filling head housing defining a filling head chamber (140), and having a filling head (220) with a fluid inlet for receiving from a source fluid to be filled in the container (510) and a filling tip (770) for delivering the fluid to the container CHARACTERIZED IN THAT a regulating valve (320) is disposed within the filling head housing for regulating flow of fluid from the filling head chamber (140) through the filling tip (770), which regulating valve is displaceable within the filling head housing in at least three positions comprising a first open position, a second closed position, and a third displacement position, wherein when the regulating valve is in its open position, fluid is allowed to flow through the filling tip (770), and when the regulating valve is in its closed position or its displacement position, flow of fluid through the filling tip (770) is blocked, the regulating valve functioning as a pushing cylinder as it moves from its closed position to its displacement position, at which it protrudes from the filling tip (770) for engagement in the spout opening (540) in a container (510), the regulating valve defining an escape path (1150) for residual fluid during such movement. Apparatus according to Claim 1, wherein an inlet passage (1170) is defined in the regulating valve (320) for supplying a cleaning gas to clean the inside of the spout opening (540) in a container (510). Apparatus according to Claim 2, wherein the escape path (1150) in the regulating valve (320) provides an outlet for the cleaning gas. Apparatus according to Claim 2 or Claim 3, wherein the inlet passage and the outlet for the cleaning gas are separated concentric passages (1170,1150) inside the regulating valve (320). Apparatus according to any preceding Claim wherein the filling head housing has a return portion for returning fluid to its source, into which portion fluid is diverted when the valve (320) is in its closed position. Apparatus according to Claim 5, wherein the return portion extends from the housing to an accumulator. Apparatus according to Claim 5 or Claim 6, including an external valve in the return portion for controlling the flow of fluid therein. Apparatus according to any preceding Claim, including a meter (1230) coupled to the fluid inlet for measuring the amount of fluid flowing into the filling head housing. Apparatus according to Claim 8, wherein the operation of the regulating valve (320) is responsive to the meter (1230). Apparatus according to any preceding Claim including means for sterilizing the filling tip (770). Apparatus according to Claim 10 wherein the filling tip (770) is within the filling head chamber (140), and the sterilizing means comprises an inlet (570) for feeding a sterilizing fluid to the filling head chamber. Apparatus according to Claim 11 wherein the inlet is coupled to a source of steam. Apparatus according to Claim 11 wherein the inlet is coupled to a source of nitrogen. A method for filling a container using apparatus according to any preceding Claim, comprising the steps of: connecting the filling tip (770) of said filling head with the spout opening (540) of a container (510); receiving fluid to be filled in the container (510) to the filling head housing through the fluid inlet; positioning the regulating valve (320) in its first open position; delivering fluid through the filling tip (770) of the filling head housing to the container (510); positioning the regulating valve to its closed position so that flow of fluid in the container is blocked; and pushing the regulating valve from its second closed position to its third displacement position so that the valve compresses against the interior surface of the spout opening and squeezes and removes residual fluid inside the spout opening. A method according to Claim 14 performed under sterile conditions. A method according to Claim 15 wherein the filling head chamber (140) is flooded with a sterilizing fluid as the container (510) is filled. A method according to Claim 16 wherein the sterilizing fluid is steam. A method according to Claim 16 wherein the sterilizing fluid is nitrogen. A method according to any of Claims 13 to 18 including the step of delivering a cleaning gas along an inlet passage (1170) in the regulating valve (320) to the inside of the spout opening (540) when the regulating valve is in its third displacement position. A method according to Claim 19 wherein the cleaning gas is steam. A method according to Claim 19 wherein the cleaning gas is nitrogen.

Inventors: RUTTER CHRISTOPHER C, RUTTER, CHRISTOPHER C.
Applicants: DS SMITH PLASTICS LTD, DS SMITH PLASTICS LIMITED
Application year: 1999
Main classification: B65B55
IPC codes: B65B55, B65B39