Filling nozzle

Abstract: A filling nozzle comprises a vertical tubular nozzle body 61, an air vent pipe 62 fixedly extending through the nozzle body 61 vertically and having a projection 62a producting downward from the body 61, a vertically movable discharge pipe 64 provided around the downward projection 62a and having an upper large-diameter portion 82 with an outside diameter permitting the portion 82 to come into contact with an opening edge of the container to be filled and a lower small-diameter portion 83 with an outside diameter permitting the portion 83 to be inserted into the opening of the container, the large-diameter portion 82 having an upper surface including a contact face 85a for a lower end face of the nozzle body 61, a seat ring 63 formed on a lower end outer face of the projection 62a for a lower end of the small-diameter portion 83 to bear on so as to form between the lower end face of the nozzle body 61 and the contact face 85a a clearance C permitting the discharge pipe 64 to move upward or downward, and a spring 66 biasing the discharge pipe 64 downward. The upper surface of the discharge pipe large-diameter portion82 has at least a part positioned inward from the contact face 85a and formed at the sage level as or a lower level than the contact face 85a. A space between the nozzle body 61 and the discharge pipe 64 is sealed off with a vertical tubular packing 67 vertically stretchable and connected between the nozzle body 61 and the discharge pipe 64.

Description: BACKGROUND OF THE INVENTION The present invention relates to a filling nozzle for use in vacuum filling machines of the rotary type for filling containers with juice or like liquid by a continuous automatic operation. As shown in FIG. 11, such filling nozzles conventionally comprise a vertical tubular nozzle body 301, an air vent pipe 302 fixedly extending through the nozzle body 301 vertically and having a projection 302a projecting downward from the body 301, a vertically movable discharge pipe 304 provided around the downward projection 302a and having an upper large-diameter portion 304a with an outside diameter permitting the portion 304a to come into contact with an opening edge of the container to be filled and a lower small-diameter portion 304b with an outside diameter permitting the portion 304b to be inserted into the opening of the container, the large-diameter portion 304a having an upper surface including a contact face 304c for the lower end face of the nozzle body 301, a seat ring 303 formed on the lower end outer face of the projection 302a for the lower end of the small-diameter portion 304b to bear on so as to form between the lower end face of the nozzle body 301 and the contact face 304c a clearance C permitting the discharge pipe 304 to move upward or downward, a spring 306 biasing the pipe 304 downward, and seal means for sealing off a space between the nozzle body 301 and the discharge pipe 304. The seal means comprises a vertically slidable guide tube 305 provided upright inwardly of the contact face 304c and slidably fitted in the nozzle body 301. With the known filling nozzle described, the clearance between the inner surface of the nozzle body 301 and the outer surface of the slidable guide tube 305 is as small as about 0.05 mm to ensure a sealing effect, whereas the liquid to be filled into containers inevitably penetrates into the clearance during the filling operation. The liquid to be filled is not removable from the clearance merely by passing a wash liquor through the nozzle body 301 when the filling nozzle is cleaned. For the removal of the liquid, therefore, the discharge pipe 304 including the guide tube 305 must be separated from the nozzle body. This impedes automatic cleaning of the filling nozzle. SUMMARY OF THE INVENTION The main object of the present invention is to provide a filling nozzle which can be cleaned without separating a discharge pipe from the body of the nozzle so as to be cleaned automatically. The present invention provides a filling nozzle which comprises a vertical tubular body; an air vent pipe fixedly extending through the nozzle body vertically and having a projection projecting downward from the nozzle body; a vertically movable discharge pipe provided around the downward projection and having an upper large-diameter portion with an outside diameter permitting the portion to come into contact with an opening edge of the container to be filled and a lower small-diameter portion with an outside diameter permitting the small-diameter portion to be inserted into the opening of the container, the large-diameter portion having an upper surface including a contact face for a lower end face of the nozzle body; a seat ring formed on a lower end outer face of the projection for a lower end of the small-diameter portion to bear on so as to form between the lower end face of the nozzle body and the contact face a clearance permitting the discharge pipe to move upward or downward; a spring biasing the discharge pipe downward; and seal means for sealing off a space between the nozzle body and the discharge pipe. The filling nozzle is characterized in that the upper surface of the discharge pipe large-diameter portion has at least a part positioned inward from the contact face and formed at the same level as, or a lower level than, the contact face, and that the seal means comprises a vertical tubular packing vertically stretchable and extending between and attached to the nozzle body and the discharge pipe. With the filling nozzle of the invention, the upper surface of the discharge pipe large-diameter portion has at least a part positioned inward from the contact face and formed at the same level as or lower level than the contact face, and the seal means comprises a vertical tubular packing vertically stretchable and connected between the nozzle body and the discharge pipe. Accordingly, the discharge pipe has no portion extending into the nozzle body, and between the nozzle body and the discharge pipe, there is no clearance for the liquid to be filled to flow in. This feature makes it possible to clean the filling nozzle without separating the discharge pipe from the nozzle body and to clean the nozzle automatically. BRIEF DESCRIPTION Of THE DRAWINGS FIG. 1 is a front view partly broken away and showing a filling machine of the invention in its entirety; FIG. 2 includes enlarged fragmentary views in section of a filling liquid tank in the machine; FIG. 3 is a view in vertical section of a filling nozzle in the machine; FIG. 4 is a view in vertical section of a device for cleaning the filling machine; FIG. 5 is a plan view of the cleaning device; FIG. 6 is a diagram illustrating an operation for applying suction to the interior of the tank; FIG. 7 is a diagram illustrating a cleaning operation by the cleaning device; FIG. 8 is a diagram illustrating another cleaning operation by the device; FIG. 9 is a diagram illustrating another cleaning operation by the device; FIG. 10 is a diagram illustrating still another cleaning operation by the device; and FIG. 11 is a view in vertical section showing a conventional example of filling nozzle. DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the invention will be described with reference to FIGS. 1 to 10. FIG. 1 shows a rotary vacuum filling machine which comprises a vertical rotary support shaft 12 provided upright on a base 11, a filling liquid tank 13 having a bottom wall supported by the upper end of the support shaft 12, a container transport table 14 positioned at a predetermined distance downward from the bottom wall of the tank 13 and secured to an intermediate portion of the height of the shaft 12, a plurality of filling nozzles 15 mounted on the bottom wall peripheral portion of the tank 13 and arranged at a given spacing, and liftable container supports 16 mounted on the peripheral portion of the table 14 and positioned immediately below the respective filling nozzles 15. A collection pipe connecting adapter 17 is provided for every two filling nozzles 15. The tank 13 has a top wall which is centrally provided with an opening portion 21 in the form of an upwardly projecting tube. The opening portion 21 has an open upper end covered with a closure 22. An annular trough 23 for collecting a wash liquor is provided around the opening portion 21. With reference to FIG. 2, a slip ring 28 of rigid synthetic resin and a seal ring 24 of soft synthetic resin inside thereof are interposed between the upper end of the opening portion 21 and the lower surface of the closure 22 over the entire periphery of the opening portion. Recesses 28a are formed in the upper face of the slip ring 28 at suitable locations. An eccentric ring 25 for lifting the closure 22 is disposed in each recess 28a. The eccentric ring 25 has connected thereto a rotating rod 27 provided with a knob 26 and rotatably attached to the closure 22. The eccentric ring 25 is rotated in contact with the bottom of the recessed portion 28a so as to direct an eccentric portion downward, whereby the closure 22 is lifted to form a wash liquor collecting clearance between the slip ring 28 and the closure 22 (as shown in FIG. 2, (b)). With reference to FIG. 1 again, the closure 22 is centrally provided with an upwardly projecting connecting tubular portion 31 having a top wall. A vertical cleaning pipe 33 equipped with a spray nozzle 32 at its lower end extends through and is attached to the top wall. A vertical liquid supply pipe 34 at the right side of the tubular portion 31 and a vertical rodlike level sensor 35 at the left side thereof extend through and are attached to the closure 22. A liquid supply three-way change-over valve 36 has one channel in communication with an open upper end of the cleaning pipe 33. A first liquid feed pipe 37 has one end connected to an unillustrated liquid feed pump and the other end connected to one of the two other channels of the valve 36. A first shutoff valve 38 has one channel communicating with an open upper end of the liquid supply pipe 34 and the other channel in communication with the other channel of the change-over valve 36. The filling liquid tank 13 is provided with a suction blower 39 and a gas-liquid separation tank 40. The blower 39 has a Suction opening communicating with one channel of a collection three-way change-over valve 41. Two valves, i.e., second and third shutoff valves 42, 43,each have one channel in communication with the separation tank 40 through the top wall thereof. A fourth shutoff valve 44 has one channel communicating with the tank 40 through its bottom wall. A first collection pipe 45 has one end connected to an unillustrated collection pump and the other end connected to one of the two other channels of the three-way change-over valve 41. A first suction pipe 46 has one end connected to the remaining channel of the valve 41 and the other end connected to the other channel of the second shutoff valve 42. A second suction pipe 47 has one end connected to the other channel of the third shutoff valve 43 and the other end connected to the tubular portion 31 of the tank 13. A second liquid feed pipe 48 having one end connected to the unillustrated liquid feed pump is connected to the other channel of the fourth shutoff valve 44. An annular second collection pipe 49 is secured to a radially intermediate portion of the container transport table 14 on its upper surface. The collection pipe 49 locally has a J-shaped connection pipe 50 extending downward and connected to the collection pump by unillustrated means. As shown in detail in FIG. 3, each filling nozzle 15 comprises a vertical tubular nozzle body 61 having an open upper end in communication with the interior of the tank 13 and suspended by the bottom wall of the tank 13, a vertical air vent pipe 62 fixedly extending through the nozzle body 61 vertically and having a projection 62a projecting downward from the nozzle body 61, a vertically movable discharge pipe 64 provided around the downward projection 62a, a seat ring 63 formed on the lower end outer face of the air vent pipe 62 and integral with the pipe 62 for the discharge pipe 64 to bear on, a compression coiled spring 66 biasing the discharge pipe 64 downward, and a tubular packing 67 extending between and attached to the nozzle body 61 and the discharge pipe 64. The nozzle body 61 comprises an upper large-diameter portion 72 and an upper small-diameter portion 73 extending downward from the portion 72 with a stepped portion 71 formed therebetween. The upper large-diameter portion 72 is internally formed at its upper end with a stay 75 having at its inner end a mount sleeve 74 for the air vent pipe. The large-diameter portion 72 has an upper male screw 76 at its lower end. The upper small-diameter portion 73 has six windows 77 each in the form of a vertically elongated slit and arranged at a spacing circumferentially of the portion 73. The wash liquor flows into or out of a space between the portion 73 and the packing 67 through these windows 77. The air vent pipe 62 has a stepped portion 78 at an intermediate portion of its height and an annular groove 79 spaced apart upward from the stepped portion 78 by a distance corresponding to the height of the mount sleeve 74. The portion of the air vent pipe 62 above the stepped portion 78 is inserted through the mount sleeve 74, with the stepped portion 78 in contact with the lower face of the sleeve 74, and a retainer 80 is fitted in the annular groove 79, whereby the air vent pipe 62 is secured to the nozzle body 61. The discharge pipe 64 comprises a lower large-diameter portion 82 and a lower small-diameter portion 83 extending downward from the portion 82 with a lower stepped portion 81 formed therebetween. The lower large-diameter portion 82 has an outside diameter permitting the portion 82 to come into contact with the opening edge of the container to be filled with a liquid. The lower small-diameter portion 83 has an outside diameter permitting the protion 83 to be inserted into the opening of the container. The large-diameter portion 82 has an upper surface outer periphery which is at the same level as the lower end face of the upper small-diameter portion 73. The lower large-diameter portion 82 is formed on its inner surface with an inward arm 85 provided with an air vent pipe guide sleeve 84 at its inner end. The sleeve 84 is fitted around the vent pipe 62. The arm 85 has an upper surface which is at a slightly lower level than the outer periphery of upper surface of the lower large-diameter portion 82, and the base portion of upper surface of the arm 85 provides a contact face 85a for the lower end face of the upper small-diameter portion 73. A clearance C for permitting the discharge pipe 64 to move upward or downward is formed between the contact face 85a and the lower end face of the upper small-diameter portion 73. The lower large-diameter portion 82 has a lower male screw 86 at its upper end. A ring 65 of rubber or like elastic material for contact with the opening edge of the container is fitted around the lower small-diameter portion 83, with the upper surface of the ring in contact with the lower stepped portion 81. The spring 66 is inserted in the nozzle body 61 around the air vent pipe 62 and held between the stary 75 and the arm 85. The packing 67 is made of rubber or like elastic material and thereby rendered stretchable, and has upper and lower flanges 91, 92 at its respective ends and an annular intermediate portion 93, C-shaped in cross section, for providing an allowance for stretching. With the packing 67 provided around the upper small-diameter portion 73, an upper cap nut 94 is screwed on the upper male screw 76 to press the upper flange 91 against the upper stepped portion 71, and a lower cap unit 95 is screwed on the lower male screw 86 to press the lower flange 92 against the lower stepped portion 81. Upper and lower thrust washers 96, 97 of metal are interposed respectively between the upper flange 91 and the top wall of the cap nut 94 and between the lower flange 92 and the top wall of the cap nut 95. The packing 67 is prevented from rotating with the nuts 94, 95 by these thrust washers 96, 97 when the nuts 94, 95 are tightened up. As shown in detail in FIGS. 4 and 5, the collection pipe connecting adapter 17 comprises a liquid receptacle 111 in the form of a flat horizontally elongated box, a laterally projecting conduit 112 integral with the receptacle 111 in communication with the interior thereof, and a tubular connector 212 having removably joined to one end thereof the forward end of the conduit 112. The receptacle 111 has a top wall which is formed with two inlet portions 113 arranged side by side for connecting thereto the discharge ends of the respective two filling nozzles 15. The inlet portion 113 has an upper end having a seal ring 114 attached thereto. The conduit 112 externally has a flange 117 at a predetermined distance from its forward end and further has a spigot 118 at the portion thereof forward from the flange 117. An O-ring 119 is provided around the spigot 118. An L-shaped suspending bracket 115 is secured to a side wall of the receptacle 111. The bracket 115 has an upper end with a buckle lock 116 attached there-to. The buckle lock 116 has an engageable arm 121 and a lever 122. The arm 121 is engageable with a hook 123 on the tank 13 when the lever 122 is in a raised state although not shown, and the bracket 115 is locked in a pulled-up state to the tank 13 when the lever 122 is laid down. The connector 212 has at the above-mentioned one end thereof a socket 211 corresponding to the spigot 118. The other end of the connector 212 serves as a pipe connection end 221, which is connected to the second collection pipe 49 by a flexible pipe 222. The connector 212 is provided at an intermediate portion of its length with a pair of support pins 213 projecting outward in directions opposite to each other. These support pins 213 are rotatably supported by support blocks 215 suspended from the bottom wall of the tank 13 by a channel bracket 214. For a filling operation, the suction blower 39 operates to aspirate air from the interior of the tank 13 through the channel indicated by arrows in FIG. 6, whereby the interior of the tank 13 is maintained at a negative pressure. On the other hand, a filling liquid sent forward through the first liquid pipe 37 is held within the tank 13 at a constant level based on an output signal from the level sensor 35. With the rotation of the support shaft 12, the tank 13 and the table 14 rotate, but the closure 22 remains unrotated. In this case, the slip ring 28 rotates with the tank 13 in sliding contact with the closure 22. This assures the tank 13 of smooth rotation. When a container is supplied onto the container support 16, the support 16 moves upward, bringing the opening edge of the container into contact with the contact ring 65 to push the ring upward, whereby the discharge pipe 64 is forced upward along with the contact ring 65. This releases the lower end of the discharge pipe 64 from the seat ring 63 and opens the discharge end. On the other hand, air is discharged from inside the container through the air vent pipe 62, whereby the interior of the container is given the same negative pressure as in the tank 13, permitting delivery of the filling liquid from the discharge end into the container. Upon the liquid inside the container reaching the same level as the lower end of the air vent pipe 62, no portion of the filling liquid is delivered into the container, but the liquid discharged ascends the air vent pipe 62. The discharge of the liquid from the nozzle 15 is discontinued upon the liquid inside the vent pipe 62 reaching the same level as the liquid Level within the tank 13. The container support 16 thereafter lowers to lower the container. The discharge pipe 64 therefore moves down, bringing its lower end into contact with the seat ring 63, whereby the discharge end is closed. At this time, the filling liquid remains in the air vent pipe 62, whereas the remaining liquid is forced up into the tank 13 by the negative pressure inside the tank 13. The filling machine is cleaned by the following operation. In preparation for cleaning, the adapters 17 are set in position for the filling nozzles 15 in the following manner. With the contact ring 65 removed from each nozzle 15, the spigot 118 of the conduit 112 is inserted into the socket 211 of the connector 212 as directed obliquely downward as indicated in a broken line in FIG. 4, and the bracket 115 is raised and fastened to the tank 13 with the buckle lock 116. This moves the discharge pipe 64 upward to open the discharge end. Next, each eccentric ring 25 is rotated to lift the closure 22 to form a clearance between the slip ring 24 and the closure 22 as previously stated. The connection pipe 50 of the second collection pipe 49 is then connected to the collection pump. When the preparation procedure has been thus completed, the following five steps are executed one after another. With reference to FIG. 7 showing the first step, the second shutoff valve 42 and the fourth shutoff valve 44 are opened, the collection three-way change-over valve 41 is so switched as to connect the first collection pipe 45 to the first suction pipe 46, and the liquid feed pump and the collection pump are operated, whereby a wash liquor is supplied to the gas-liquid separation tank 40 and the first suction pipe 46 through the second liquid feed pipe 48 and collected via the first collection pipe 45 as indicted by arrows in FIG. 7. With reference to FIG. 8 showing the second step, the second shutoff valve 42 is closed and the third shutoff valve 43 is opened to supply the wash liquor to the gas-liquid separation tank 40 as in the first step. At this time, the wash liquor flows through the second suction pipe 47 into the filling liquid tank 13. The wash liquor flowing into the tank 13 flows down the nozzle 15 into the receptacle 111 via the nozzle discharge end, further flows through the conduit 112 and the connector 212 and is collected by way of the second collection pipe 49. In the third step illustrated in FIG. 9, the liquid supply three-way change-over valve 36 is so manipulated as to bring the first liquid feed pipe 37 into communication with the first shutoff valve 38, which is then opened to supply the wash liquor via the first liquid feed pipe 37. The liquid supplied flows through the liquid supply pipe 34 into the tank 13 and is collected in the same manner as in the second step. In the fourth step illustrated in FIG. 10, the change-over valve 36 is manipulated to bring the first liquid feed pipe 37 into communication with the cleaning pipe 33 to similarly supply the wash liquor via the first liquid feed pipe 37. The liquor flows down the cleaning pipe 33 and is sprayed through the nozzle 32. This cleans the entire interior of the tank 13 and also the opposed peripheries of the closure 22 and the opening portion 21. In the fifth step, the collection pump is stopped, and the change-over valve 36 is manipulated in the same manner as in the third step to open the first shutoff valve 38 and supply the wash liquor to the tank 13 via the first liquid feed pipe 37 and the liquid supply pipe 34. Upon the liquid level within the tank 13 rising to a level higher than the upper end of the air vent pipe 62, the collection pump is operated. This forces the wash liquor within the tank 13 to flow down the filling nozzle 15 continuously to clean the entire interior of the nozzle 15, especially the inside of the air vent pipe 62. The five steps described are executed repeatedly using different kinds of wash liquors, for example, hot water, alkali solution, etc. On completion of the above procedures, water serving as a wash liquor is finally supplied to the tank 13 through the liquid supply pipe 34 with the collection pump held out of operation as in the fifth step. Water is continuously supplied until it overflows the tank 13. The overflow is collected by the trough 23. When the cleaning operation has been completed in this way, the closure 22 is closed, and each adapter 17 is removed from the filling nozzle 13 by a procedure reverse to the setting procedure described, whereby the machine is made ready for a filling operation.

Claims: A filling nozzle comprising: a vertical tubular nozzle body 61, an air vent pipe 62 fixedly extending through the nozzle body 61 vertically and having a projection 62a projecting downward from the nozzle body 61, a vertically movable discharge pipe 64 provided around the downward projection 62a and having an upper large-diameter portion 82 with an outside diameter permitting the portion 82 to come into contact with an opening edge of the container to be filled and a lower small-diameter portion 83 with an outside diameter permitting the portion 83 to be inserted into the opening of the container, the large-diameter portion 82 having an upper surface including a contact face 85a for a lower end face of the nozzle body 61, a seat ring 63 formed on a lower end outer face of the projection 62a for a lower end of the small-diameter portion 83 to bear on so as to form between the lower end face of the nozzle body 61 and the contact face 85a a clearance C permitting the discharge pipe 64 to move upward or downward, a spring 66 biasing the discharge pipe 64 downward, and seal means for sealing off a space between the nozzle body 61 and the discharge pipe 64, the filling nozzle being characterized in that the upper surface of the discharge pipe large-diameter portion 82 has at least a part positioned inward from the contact face 85a and formed at the same level as or a lower level than the contact face 85a, the seal means comprising a vertical tubular packing 67 vertically stretchable and extending between and attached to the nozzle body 61 and the discharge pipe 64. A filling nozzle as defined in claim 1 wherein the discharge pipe 64 is provided with an inward arm 85 on its inner surface, and a guide sleeve 84 is provided on the inner end of the arm 85 and fitted around the air vent pipe 62. A filling nozzle as defined in claim 1 wherein the nozzle body 61 has a small-diameter portion 73 inserted in the packing 67 and a large-diameter portion 72 integral with an upper end of the portion 73, windows 77 being formed in the small-diameter portion 73 for holding its inside in communication with the outside thereof, the nozzle body large-diameter portion 72 having an upper male screw 76, the discharge pipe large-diameter portion 82 having a lower male screw 86, the packing 67 having upper and lower flanges 91, 92 at its respective ends, upper and lower cap nuts 94, 95 being screwed on the upper and lower male screws 71, 86 respectively for pressing the upper flange 91 against a lower surface of the nozzle body large-diameter portion 72 and the lower flange 92 against the upper surface of the discharge pipe large-diameter portion 82. A filling nozzle as defined in claim 3 wherein upper and lower thrust washers 96, 97 are interposed between the upper flange 91 and the upper cap unit 94 and between the lower flange 92 and the lower cap unit 95 respectively.

Inventors: IUCHI TETSUYA C O SHIKOKU KAKO, MIKI TAKAO C O SHIKOKU KAKOKI, MIKI YOSHIFUMI C O SHIKOKU KAK, UEDA MICHIO C O SHIKOKU KAKOKI, IUCHI, TETSUYA, C/O SHIKOKU KAKOKI CO., LTD., MIKI, TAKAO, C/O SHIKOKU KAKOKI CO., LTD., MIKI, YOSHIFUMI, C/O SHIKOKU KAKOKI CO., LTD., UEDA, MICHIO, C/O SHIKOKU KAKOKI CO., LTD.
Applicants: SHIKOKU KAKOKI CO LTD, SHIKOKU KAKOKI CO., LTD.
Application year: 1993
Main classification: B67C3
IPC codes: B67C3