AU2009201707A1

AU2009201707A1 - Screwcap

Info

Publication number: AU2009201707A1
Application number: AU2009201707A
Authority: AU
Inventors: Udo Schutz
Original assignee: Protechna SA
Current assignee: Protechna SA
Priority date: 2008-07-04
Filing date: 2009-04-29
Publication date: 2010-01-21
Anticipated expiration: 2029-04-29
Also published as: DE102008031736B3; ES2364542T3; DE502009000523D1; CN101618776B; AU2009201707B2; US20100000998A1; MX2009005162A; AR071503A1; ATE505409T1; MY151725A; JP5183580B2; ZA200903114B; JP2010013187A; AU2009201707C1; SA109300321B1; RU2404907C1; EP2141083A1; BRPI0902018B1; BRPI0902018A2; CN101618776A

Description

AUSTRALIA Patents Act COMPLETE SPECIFICATION (ORIGINAL) Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority Related Art: Name of Applicant: Protechna S.A. Actual Inventor(s): Udo Schutz Address for Service and Correspondence: PHILLIPS ORMONDE FITZPATRICK Patent and Trade Mark Attorneys 367 Collins Street Melbourne 3000 AUSTRALIA Invention Title: SCREWCAP Our Ref: 852579 POF Code: 20412/106282 The following statement is a full description of this invention, including the best method of performing it known to applicant(s): -1 - 2 Screwcap This application claims priority from German Application No.10 2008 031 736.5 filed on 4 July 2008, the contents of which are to be taken as incorporated herein 5 by this reference. The invention concerns a screwcap from plastic material with a cover disc and an external cover edge perpendicularly adjoining its circumference with an internal thread to close a filling and/or discharging socket of a container for the transport 10 and storage of liquids as well as with a central bung socket provided countersunk in the cover disc with internal thread to screw in the bung plug. From EP 0 650 446 B1 screwcaps of the generic type are known for closing the filling socket of a drum with bung or the plastic inner container of a pallet 15 container with an external jacket from grate rods or sheet metal have the disadvantage that the sealing ring to seal the bung plug in the bung socket of the screwcap no longer assures the sealing of the bung plug closure due to the ageing of the material of the sealing ring, in particular of containers used for transport and storage of chemical liquids, so that the sealing ring has to be 20 regularly replaced. The object of the invention is to improve the screwcap of the generic type with regard to an improved sealing of the bung plug closure, a more cost-effective manufacture as well as to lower the operating expenses of the container for liquid 25 fitted with the screwcap and used as multiple use container. According to the invention this objective is achieved by a screwcap according to the features of patent claims 1, 7 and 8. 30 The sub-claims contain advantageous and useful developments of the invention. The screwcap according to the invention with a bung socket, that is fitted with a bung plug closure, is characterised by the following advantages: 3 The design of the plastic bung plug for closing the bung socket of the screwcap with a tapered multiple seal integrally injection moulded with it in the form of sealing rings spaced from one another, which in the case of a screwed-in bung plug are pressed against a tapered internal sealing surface of the bung plug, 5 makes an optimum sealing of the bung plug closure possible. In the case of containers with internal pressure the sealing of the bung plug closure for the bung socket of the screwcap is further improved by that the pressure of the sealing rings of the tapered multiple seal of the plug, brought about by the screwing in of the bung plug, against the tapered internal sealing surface of the bung socket is 10 additionally increased due to the internal pressure of the container acting on the internal wall of the sealing end of the bung plug with the multiple sealing of the screw-in sleeve. Due to the absence of a sealing ring, that has to be regularly replaced, the manufacturing expenses can be reduced in comparison with known screwcaps with a bung socket that is closed by a bung plug with a sealing ring, as 15 well as the operating expenses of the container for liquid that is fitted with a screwcap with the new bung plug closure for the bung socket of the cover which are used as multiple use containers. In the following the invention is explained based on the figures of the drawing 20 which show the following in: Fig.1 - a longitudinal section of a screwcap with a central bung socket that is enclosed by a bung plug, and 25 Fig.2 - an enlarged detailed illustration of the screwcap of Fig.1, and the Figs.3 and 4 - enlarged detailed illustrations of two further embodiments of the screwcap. 30 The screwcap 1, manufactured from plastic as an injection moulded part, has a flat cover disc 2, an external cover edge 3 perpendicularly adjoining its circumference with an internal thread 4 to close a filling and/or discharging socket of a container for the transport and storage of liquids, as well as an inner skirt 5. The inner skirt 5 is concentrically arranged with the external cover edge 3, form 4 with it a sealing bed 6 to insert a sealing ring to seal the screwcap 1 on the upper edge of the filling and/or discharging socket of the container for liquids and serves the purpose of reinforcement as well as of a better seat of the screwcap on the socket of the container. 5 In the cover disc 2 a central bung socket 7 is provided in a countersunk manner; said bung socket can be closed by a bung plug 8 manufactured as an injection moulded plastic part. The bung plug 8 is fitted with a cylindrical screw-in sleeve 9 with an external 10 thread 10 for screwing it into the threaded bore 11 of the bung socket 7 of the screwcap 1. The screw-in sleeve 9 of the bung plug 8 has a sealing end 12, onto which a tapered multiple seal 13 is moulded that is formed by four sealing rings 14 with a rounded sealing edge 14a, said sealing rings spaced from one another by grooves 15 and concentrically provided with the longitudinal axis 16-16 of the 15 plug and the diameters 17 of which are reducing in the direction a of screwing in the bung plug 8. In the case of a screwed-in bung plug 8 the sealing rings 14 of the tapered multiple seal 13 at the sealing end 12 of the bung plug 8 are pressed against a 20 corresponding tapered internal sealing surface 18 of a sealing neck 19 adjoining the threaded bore 11 of the bung socket 7 of the screwcap 1. In the case of a further embodiment of the screwcap 1 a ventilation device or a ventilation and aeration device is integrated in the bung plug 8. 25 To fill a single container through the bung socket 7 of the screwcap 1 screwed on the filler socket of the container the bung plug 8 is unscrewed manually from the bung socket 7 of the screwcap 1 using a bung wrench and a pump is connected to the bung socket. When filling a plurality of containers through the bung socket 30 7 of the screwcap 1 screwed on the filler socket of the container using automatic filling equipment, the bung plugs 7 are unscrewed from the screwcaps 1 by a machine.

5 The bung plug 8 of a further embodiment of the screwcap, illustrated in Fig.3, has a cylindrical screw-in sleeve 9 with an external thread 10 to be screwed into the threaded hole 11 of the bung socket 7 of the screwcap 1 as well as with a sealing end 12, said sealing end having an integrally formed sealing ring 14 that has a 5 rounded sealing edge 14a, that in the case of a screwed in bung plug 8 is pressed against a tapered internal sealing surface 18 of a sealing neck 19 adjoining the threaded bore 11 of the bung socket 7 of the screwcap 1. The bung plug 8 of a further embodiment of the screwcap, illustrated in Fig.4, has 10 a cylindrical screw-in sleeve 9 with an external thread 10 to be screwed into the threaded bore 11 of the bung socket 7 of the screwcap 1 as well as with a sealing end 12 having a tapered sealing edge 20 that with the bung plug 8 screwed in is pressed against a tapered internal sealing surface 18 of a sealing neck 19 adjoining the threaded bore 11 of the bung socket 7 of the screwcap 1.

6 List of reference numerals 1 Screwcap 2 Cover disc 3 External cover edge of 1 4 Internal thread of 3 5 Inner skirt of 1 6 Sealing bed between 3 and 5 7 Bung socket in 2 8 Bung plug of 7 9 Screw-in sleeve of 8 10 External thread of 9 11 Threaded bore of 7 12 Sealing end of 9 13 Tapered multiple seal of 12 14 Sealing ring of 13 14a Sealing edge of 14 15 Groove between 14, 14 16-16 Longitudinal axis of plug 17 Diameter of 14 18 Tapered sealing surface of 19 19 Sealing neck of 7 20 Tapered sealing edge of 12 (Fig.4) a Direction of screwing in of 8

Claims

1. Screwcap from plastic material with a cover disc and an external cover edge perpendicularly adjoining its circumference with an internal thread to close a 5 filling and/or discharging socket of a container for the transport and storage of liquids as well as with a central bung socket provided countersunk in the cover disc with internal thread to screw in the bung plug, characterised in that the bung plug (8) has a cylindrical screw-in sleeve (9) with an external thread (10) for screwing it into the threaded bore (11) of the bung socket (7) of the 10 screwcap (1) as well as a sealing end (12), said sealing end being provided with a tapered multiple seal (13) formed by sealing rings (14) which in the case of a screwed-in bung plug (8) are pressed against a tapered internal sealing surface (18) of a sealing neck (19) adjoining the threaded bore (11) of the bung socket (7) of the screwcap (1). 15

2. Screwcap according to claim 1, characterised by four sealing rings (14) moulded on the sealing end (12) of the screw-in sleeve (9) of the bung plug (8) which are spaced from one another by grooves (15) and are concentrically provided with the longitudinal axis (16-16) of the plug and the diameters (17) 20 of which are reducing in the direction (a) of screwing in the bung plug (8) corresponding to the tapered internal sealing surface (18) of the sealing neck (19) of the bung socket (7) of the screwcap (1).

3. Screwcap according to claim 2, characterised in that the sealing rings (14) 25 have a rounded sealing edge (14a).

4. Screwcap according to any one of claims 1 to 3, characterised by a bung plug (8) with an integrated ventilation device. 30

5. Screwcap according to any one of claims 1 to 3, characterised by a bung plug (8) with an integrated ventilation and aeration device. 8

6. Screwcap according to any one of claims 1 to 5, characterised in that the screwcap (1) and the bung plug (8) are manufactured as injection moulded plastic parts. 5

7. Screwcap from plastic material with a cover disc and an external cover edge perpendicularly adjoining its circumference with an internal thread to close a filling and/or discharging socket of a container for the transport and storage of liquids as well as with a central bung socket provided countersunk in the cover disc with internal thread to screw in the bung plug, characterised in that the 10 bung plug (8) has a cylindrical screw-in sleeve (9) with an external thread (10) for screwing it into the threaded bore (11) of the bung socket (7) of the screwcap (1) as well as a sealing end (12), said sealing end fitted with an integrally formed sealing ring (14) that has a rounded sealing edge (14a), that in the case of a screwed in bung plug (8) is pressed against a tapered internal 15 sealing surface (18) of a sealing neck (19) adjoining the threaded bore (11) of the bung socket (7) of the screwcap (1).

8. Screwcap from plastic material with a cover disc and an external cover edge perpendicularly adjoining its circumference with an internal thread to close a 20 filling and/or discharging socket of a container for the transport and storage of liquids as well as with a central bung socket provided countersunk in the cover disc with internal thread to screw in the bung plug, characterised in that the bung plug (8) has a cylindrical screw-in sleeve (9) with an external thread (10) for screwing it into the threaded bore (11) of the bung socket (7) of the 25 screwcap (1) as well as a sealing end (12), said sealing end having a tapered sealing edge (20) that with the bung plug (8) screwed in is pressed against a tapered internal sealing surface (18) of a sealing neck (19) adjoining the threaded bore (11) of the bung socket (7) of the screwcap (1).