CA1316962C - Methods of manufacturing tube coupling bodies - Google Patents
Methods of manufacturing tube coupling bodiesInfo
- Publication number
- CA1316962C CA1316962C CA000594697A CA594697A CA1316962C CA 1316962 C CA1316962 C CA 1316962C CA 000594697 A CA000594697 A CA 000594697A CA 594697 A CA594697 A CA 594697A CA 1316962 C CA1316962 C CA 1316962C
- Authority
- CA
- Canada
- Prior art keywords
- open end
- moulding
- tube
- ring
- annular
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/17—Component parts, details or accessories; Auxiliary operations
- B29C45/26—Moulds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/17—Component parts, details or accessories; Auxiliary operations
- B29C45/26—Moulds
- B29C45/261—Moulds having tubular mould cavities
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/0053—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor combined with a final operation, e.g. shaping
- B29C45/0055—Shaping
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C57/00—Shaping of tube ends, e.g. flanging, belling or closing; Apparatus therefor, e.g. collapsible mandrels
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C69/00—Combinations of shaping techniques not provided for in a single one of main groups B29C39/00 - B29C67/00, e.g. associations of moulding and joining techniques; Apparatus therefore
- B29C69/02—Combinations of shaping techniques not provided for in a single one of main groups B29C39/00 - B29C67/00, e.g. associations of moulding and joining techniques; Apparatus therefore of moulding techniques only
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L37/00—Couplings of the quick-acting type
- F16L37/08—Couplings of the quick-acting type in which the connection between abutting or axially overlapping ends is maintained by locking members
- F16L37/084—Couplings of the quick-acting type in which the connection between abutting or axially overlapping ends is maintained by locking members combined with automatic locking
- F16L37/092—Couplings of the quick-acting type in which the connection between abutting or axially overlapping ends is maintained by locking members combined with automatic locking by means of elements wedged between the pipe and the frusto-conical surface of the body of the connector
- F16L37/0925—Couplings of the quick-acting type in which the connection between abutting or axially overlapping ends is maintained by locking members combined with automatic locking by means of elements wedged between the pipe and the frusto-conical surface of the body of the connector with rings which bite into the wall of the pipe
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L37/00—Couplings of the quick-acting type
- F16L37/08—Couplings of the quick-acting type in which the connection between abutting or axially overlapping ends is maintained by locking members
- F16L37/084—Couplings of the quick-acting type in which the connection between abutting or axially overlapping ends is maintained by locking members combined with automatic locking
- F16L37/092—Couplings of the quick-acting type in which the connection between abutting or axially overlapping ends is maintained by locking members combined with automatic locking by means of elements wedged between the pipe and the frusto-conical surface of the body of the connector
- F16L37/0927—Couplings of the quick-acting type in which the connection between abutting or axially overlapping ends is maintained by locking members combined with automatic locking by means of elements wedged between the pipe and the frusto-conical surface of the body of the connector the wedge element being axially displaceable for releasing the coupling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2031/00—Other particular articles
- B29L2031/24—Pipe joints or couplings
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S264/00—Plastic and nonmetallic article shaping or treating: processes
- Y10S264/66—Processes of reshaping and reforming
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49826—Assembling or joining
- Y10T29/49863—Assembling or joining with prestressing of part
- Y10T29/49876—Assembling or joining with prestressing of part by snap fit
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/53—Means to assemble or disassemble
- Y10T29/5367—Coupling to conduit
Abstract
ABSTRACT
IMPROVEMENTS IN OR RELATING TO METHODS OF
MANUFACTURING TUBE COUPLING BODIES
The disclosure relates to a method of manufacturing a tube coupling body in a plastics material using injection moulding tooling. The body is formed with a cylindrical bore having enlarged end portions in a mould body and using removable cores.
The cores form both the internal bore of the mould body and also end parts of the mould body so that once the cores are removed, end parts of the coupling body are revealed in the mould. Whilst the end parts are still hot from the initial moulding operating, forming dies having tapering end cavities are pressed over the end parts of the moulding to form the end parts of the moulding with both external and corresponding internal tapered surfaces. The tapered internal surfaces of the end parts thus formed provide tapered cam surfaces for engaging the resilient arms of collets to be inserted in the coupling body to receive and lock tubes in the coupling body.
IMPROVEMENTS IN OR RELATING TO METHODS OF
MANUFACTURING TUBE COUPLING BODIES
The disclosure relates to a method of manufacturing a tube coupling body in a plastics material using injection moulding tooling. The body is formed with a cylindrical bore having enlarged end portions in a mould body and using removable cores.
The cores form both the internal bore of the mould body and also end parts of the mould body so that once the cores are removed, end parts of the coupling body are revealed in the mould. Whilst the end parts are still hot from the initial moulding operating, forming dies having tapering end cavities are pressed over the end parts of the moulding to form the end parts of the moulding with both external and corresponding internal tapered surfaces. The tapered internal surfaces of the end parts thus formed provide tapered cam surfaces for engaging the resilient arms of collets to be inserted in the coupling body to receive and lock tubes in the coupling body.
Description
131696~
IMPROVEMENTS IN OR RELATING TO METHODS OF
MANUFACTUXING TUBE COUPLING BODIES, BACKGROUND OF THE INVENT,ION
1. Field of the invention This invention r1ates to methods o~
manufacturing tube coupling bodies and is particularly, although not exclusively, applicable to methods o~ manufacturing tube coupling bodies for couplings of the type described and i:Llustrated in our UK Patent Specification No. 1520742. The latter:
specification describes and illustrates a tube coupIing comprising a body having a throughway open at one end of the body with a frus~o conical cam surface in the throughway tapering towards said open end of the throughway, a collet located in the open end of the throughway having resilient fingers extending into the throughway to grip and engage a tube inserted through the collet into the body, the -, 20 arrangement being such that movement of the tube in a ; directlon~outwardly of the throughway causes the arms of the collet to be orced into engagement with:the tube by the tapered cam surface to grip and hold`the tube in the coupling body.
~ 2. Background prior art EP-A-0132319 discloses:a method of manufacturing a;coupling body for such a~tube : : coupling~in moulded plastics in which the coupling ;~
:body is moulded in one operation without the tapered ~ cam~surface~and the cam surface is:moulded~in~:
plastics~:in~a separate annular insert to be located in the open~;end of the~coupling~body. ,The:insert is : : subsequently joined to the coupling body by : ul~rasonic welding to form a cohesive unit with the ~: ~: : 35 body.
The object of the present invention is to `` ` 1 31 ~962 simplify the manufactura of the coupling body.
SUMMARY OF_T~E INVENTION
This invention provides a method of manufacturing a tube coupling body having a throughway to receive a tube from an op~en end of the throughway to ~e secured in the coupling body, the method comprising the steps of initiall~y moulding the body with a non-convergent throughway extending to said open end and, whilst the moulding is hot from the moulding operation, releasing at least a part of the moulded body adjacent said open end from the mould and applying a shaped die to the external surface of that end part to re-form said end part wi~h an internal cross-section which reduces towards said open end.
In one method according to the invention the step of initially moulding the body may form the body with a parallel sided throughway extending to said open end.
In a further method accoridng to the invention the step of initially moulding the body may form the body with a divergent throughway extending to said open end.
In any of the above methods the step of re-forming said end parts may form the internal cross-section with a tapered surface which converges towards said open end.
Also in any of the above methods the step of initially moulding the body may form the external surface of the body with a reducing taper towards said open end of the body.
The die may have a cavity which is tapered as it extends into the die to form an external taper on said end part of the coupling body and a corresponding internal tapered surface in the end part of the moulded body to form a cam surface for acting on the resilient arms of a collet to be inserted in the end part of the moulded body for clamping a tube in the body.
More ~pecifically the body may be moulded in a mould having a cavity shaped to form an external surface of the body and a removable core shaped to form the internal surface of the body, the core having an annular recess to co-operate with the mould cavity in forming an annular end part of the body whereby, after moulding the body, removal of the core exposPs the annular part of the moulded body on which said die forming operation is then performed.
According to a further feature a reinforcement ring may be applied to the external surface of the annular end part of the body around at least the part of the body containing the internal tapered surface to strengthen the end part of the body. For example the reinforcement ring may be welded to the body.
Alternatively the reinforcement ring may be formed with an inwardly projecting annular rib and the external surface of the body is formed with an ~: :annualar groove in which the rib is engageable to retain the ring on the body.
In a further arrangement the external surface of the body may be formed with an annular shoulder :~ ~acing away from the open end of the body and the : reinforcing ring encircles~the part of the body between the shoulder and the open end of the body with a rib on the ring engaging the shoulder to retain the ring on the body.
~ he:ring;~may be form:ed to project beyond the open end of the body and is~ formed with an inturned flange spaced from the open end to retain:a collet located in the open end of the body for coupling a tube to the body.
In any of thr above methods the body may be .
~ 4 ~ l 3l 6q 62 formed with a plurality oE annular open ends in said moulding operation and each of ~aid end parts of the moulding is released whilst still hot and subjected to said die forming operation to re~form each end part with an intexnal tapered surface which reduces a cross-section towards the open end thereof.
The invention al50 provides a tube coupling body having a throughway to receive a tube from an open end of the throughway to be secured in the coupling body, the body comprising a pre-formed plastics moulding with a post-formed annular open end part having an internal surface which reduces towards the open end thereof to receive a collet projecting into the open end and ha~ing a plurality of resilient fingers engagable with the tapered surface to compress the fingers against a tube extending through the collet to lock the tube in the body.
A reinforcement ring may be applied to the external surface of the annular end part of the body around at least that paxt of the body containing the internal reducing surface to strengthen said end part of the body.
: For example the reinforcement ring may be welded to the body.
Alternatively the reinforcement ring may be formed with an inwardly projecting annular rib and the external surface of the body is formed with an annular groove in which the rib is held with a "snap-in" engagement to retain the ring on the body.
In a further arrangement the external surface of the body may be formed with an annular shoulder facing away from the the open end of the body and the reinforcing ring encircles the part of the body between the shoulder and the open end of the body with a rib on the ring engaging the shoulder to retain the ring on the body.
~ 5 ~ l 3l 6q ~?
The ring may project beyond the open end of the body and is formed with an inturned flange spaced from the open end to retaln a collet location in the open end of the body for coupling a tube to the body.
BRIEF DESCRIPTION OF THE DRAWI:NGS
Figure l is a sectional view through an injection mould tool for part forming a coupling body for a tube couplins;
Figure 2 is a similar view to Figur 1 showing the moulded body with the cores of the tooling removed;
Figure 3 shows a further forming operation being carried ouk on the ends of the coupling body whilst still located in the mould of the tooling;
Figure 4 shows the finished coupling body ready for ejection from the mould;
Figure 5 shows various completed tube couplings having coupling bodies formed by apparatus of the form illustrated in Figures 1 ko 4;
Figures 6 and 7 show a modified form of the ~ mould~tooI of Figure l;
; Figure 8~shows the application of:reinforcing ring to the formed end o~ the coupl1ng body; and Figures 9 to 11 shown various further : 25 ~ ~ reinforcement arrangements.:~
:: DESCRIPT ON_OF ~HE PREFERRED EMBODIMENTS
Referring ~irstly to:Figure 1 of the drawings, :: there is shown tooling for injection moulding of a partly formed coupling body 10 in a plastics material such as polysulphone. The body~comprises a central ~: ~: cylindrical portion 11 having~an inner annular rib 12 ::: at its centre and enlarged diameter cylindrical end portlons 13 joined to the central portion by steps 14. The mould tooling comprises a mould body 15 having a:mouId cavity 16 shaped to *orm the outer : surfaca of the cen~ral portion 12 of the mould body ::
1 31 6q62 and adjacent parts of the end portions. 13.
Cylindrical removable cores 17 project into the mould cavity from opposite sides thereof and have reduced diameter spigots 18 at the orward ends thereof shaped to for~ together the inner sur~ace of the mould body. Each core, has at the juncti.on between the spigot 18 and main body 17 an annular recess 19 the inner surface of which forms a continuation of the surface of the spigot 1~3 and the outer surface of which forms a csntinuation of the adjacent mould surface 13. The recesses form the end parts of the coupling body.
After injecting plastics into khe mould to create the coupling body, the cores 17 are extracted once the plastics has set sufficiently to be self supporting whilst still being relatively hot to leave the part moulded coupling body in the mould cavity as shown in Figure 2. It will he seen that end parts indicated at 13a of the coupling body are left unsupported in the mould. Cylindrical forming dies 20 are now inserted in the mould 15 as shown in Figure 3, each die having a kapering end cavity 21 to receive and form the end part 13a of the coupling body tapering the outer surfaces of the coupling body and causing a corresponding taper on the inner surfaces of the coupling body. At the bottom of each taper cavity 21, there is a short cylindrical portion 22 which forms a short cylindrical end at the tapered : end of the body. The cores are then separated from the mould leaving the moulded coupling body in the : mould as shown i~n Figure 4 ready for ejection from the mould.
Figure 5 shows a number of different forms of coupling body which can be manufactured using this technique. 30 indicates a coupling body of straight cylindrical form open ak both ends as manufactured by - 7 - 1316~62 the tooling described above. A modified form of the tooling enables a T shaped coupling body to be created as shown at 31 and a further modified form of tooling enables an elbow form to be created as shown at 32.
The main advantage with this invention is that it reduces considerably the cost o~ manufacture as it is much quicker and easier to provide the recessed end forms shown in this manner within the mould, whilst the component is still in the hot condition.
For large pipe fittings it is possible to produce the recessed final form by the use of collapsible cores, but these are of necessitry more complex and far more costly arrangem~nts. On very small pipe sizad collapsible cores of this type are not practical and other more exp0nsive methods have to be employed.
Figures 6 and 7 show a modified form of the mould tooling described above with reference to Figure 1. The modifications relate to the removable cords 17 in which the outer surface l9a of the recess tapers towards the bottom of the recess instead of being of cylindrical form by an angIe Rl as :indicated on Figure 7 to form the end part of the coupling body moulding with a tapered external surface. A portion 18a of the spigot 18 extending into the recess 19 is also tapered to increase in diameter towards the bottom of the recess 19 to form the inner su~face of the end portion of the moulding : with~a tapered angle R 2 as iIlustrated in Figure ~7. After extraction of the cause 17 the tapered end ~ part of the moulding are post-moulded as described : above with reference to Figure 3.
Referring now to Figure 8 of the drawings, the post-formed moulding is shown before removal from the mould body 15 immediately after retraction of the forming dyes 20. :Tapered rings 40 are then applied - 8 _ 1 31 6q62 to the extexnal surface of the tapered end parts 13a created in the post-~orming operation, the rings being raised to snap into grooves formed in the tapered end parts or being welded or swaged onto the tapexed end parts. The reinforcing ring~ are applied before the post-~ormed end parts have achieved a permanent set or that is before a permanent change in the elastic material of the moulding has taken place e.g. cross linking of a polyethylene plastics material. Reinforcing rings ensure that the tapered end parts are held permanently in the po~t-formed shape and also assist in resisting the loads imposed on the tapered end parts by the tube gripping column that is located in the e~ds of the coupling in use.
Further more elaborate forms of reinforcing members for the moulded coupling bodies are illustrated in Figures 9 to 11 which will now be referred to. In Figure 9, the whole of the end part 13a of the mould is encircled by the correspondingly shaped reinforcing sleeve 41. The outer surface of the moulding 13 is formed with a groove 42 in which an integral rib 43 on the sleeve 41 is a "snap-in"
engagement to hold the sleeve on the end part 13a.
Figure 10 shows a further arrangement in which the sleeve 41 is extended to the stepped shoulder 14 in the coupling body and the rib 43 on the sleeve snaps over the shoulder 41 to retain the sleeve on the end part of the coupling body~ In the arrangements shown in Figure 11 the sleeve 41 has a cylindrical extension 44 which projects beyond the open end of the coupling body and is formed with an inturned end flange 45 which acts to retain collet 46 in the coupling body which locks a tube in the coupling body.
IMPROVEMENTS IN OR RELATING TO METHODS OF
MANUFACTUXING TUBE COUPLING BODIES, BACKGROUND OF THE INVENT,ION
1. Field of the invention This invention r1ates to methods o~
manufacturing tube coupling bodies and is particularly, although not exclusively, applicable to methods o~ manufacturing tube coupling bodies for couplings of the type described and i:Llustrated in our UK Patent Specification No. 1520742. The latter:
specification describes and illustrates a tube coupIing comprising a body having a throughway open at one end of the body with a frus~o conical cam surface in the throughway tapering towards said open end of the throughway, a collet located in the open end of the throughway having resilient fingers extending into the throughway to grip and engage a tube inserted through the collet into the body, the -, 20 arrangement being such that movement of the tube in a ; directlon~outwardly of the throughway causes the arms of the collet to be orced into engagement with:the tube by the tapered cam surface to grip and hold`the tube in the coupling body.
~ 2. Background prior art EP-A-0132319 discloses:a method of manufacturing a;coupling body for such a~tube : : coupling~in moulded plastics in which the coupling ;~
:body is moulded in one operation without the tapered ~ cam~surface~and the cam surface is:moulded~in~:
plastics~:in~a separate annular insert to be located in the open~;end of the~coupling~body. ,The:insert is : : subsequently joined to the coupling body by : ul~rasonic welding to form a cohesive unit with the ~: ~: : 35 body.
The object of the present invention is to `` ` 1 31 ~962 simplify the manufactura of the coupling body.
SUMMARY OF_T~E INVENTION
This invention provides a method of manufacturing a tube coupling body having a throughway to receive a tube from an op~en end of the throughway to ~e secured in the coupling body, the method comprising the steps of initiall~y moulding the body with a non-convergent throughway extending to said open end and, whilst the moulding is hot from the moulding operation, releasing at least a part of the moulded body adjacent said open end from the mould and applying a shaped die to the external surface of that end part to re-form said end part wi~h an internal cross-section which reduces towards said open end.
In one method according to the invention the step of initially moulding the body may form the body with a parallel sided throughway extending to said open end.
In a further method accoridng to the invention the step of initially moulding the body may form the body with a divergent throughway extending to said open end.
In any of the above methods the step of re-forming said end parts may form the internal cross-section with a tapered surface which converges towards said open end.
Also in any of the above methods the step of initially moulding the body may form the external surface of the body with a reducing taper towards said open end of the body.
The die may have a cavity which is tapered as it extends into the die to form an external taper on said end part of the coupling body and a corresponding internal tapered surface in the end part of the moulded body to form a cam surface for acting on the resilient arms of a collet to be inserted in the end part of the moulded body for clamping a tube in the body.
More ~pecifically the body may be moulded in a mould having a cavity shaped to form an external surface of the body and a removable core shaped to form the internal surface of the body, the core having an annular recess to co-operate with the mould cavity in forming an annular end part of the body whereby, after moulding the body, removal of the core exposPs the annular part of the moulded body on which said die forming operation is then performed.
According to a further feature a reinforcement ring may be applied to the external surface of the annular end part of the body around at least the part of the body containing the internal tapered surface to strengthen the end part of the body. For example the reinforcement ring may be welded to the body.
Alternatively the reinforcement ring may be formed with an inwardly projecting annular rib and the external surface of the body is formed with an ~: :annualar groove in which the rib is engageable to retain the ring on the body.
In a further arrangement the external surface of the body may be formed with an annular shoulder :~ ~acing away from the open end of the body and the : reinforcing ring encircles~the part of the body between the shoulder and the open end of the body with a rib on the ring engaging the shoulder to retain the ring on the body.
~ he:ring;~may be form:ed to project beyond the open end of the body and is~ formed with an inturned flange spaced from the open end to retain:a collet located in the open end of the body for coupling a tube to the body.
In any of thr above methods the body may be .
~ 4 ~ l 3l 6q 62 formed with a plurality oE annular open ends in said moulding operation and each of ~aid end parts of the moulding is released whilst still hot and subjected to said die forming operation to re~form each end part with an intexnal tapered surface which reduces a cross-section towards the open end thereof.
The invention al50 provides a tube coupling body having a throughway to receive a tube from an open end of the throughway to be secured in the coupling body, the body comprising a pre-formed plastics moulding with a post-formed annular open end part having an internal surface which reduces towards the open end thereof to receive a collet projecting into the open end and ha~ing a plurality of resilient fingers engagable with the tapered surface to compress the fingers against a tube extending through the collet to lock the tube in the body.
A reinforcement ring may be applied to the external surface of the annular end part of the body around at least that paxt of the body containing the internal reducing surface to strengthen said end part of the body.
: For example the reinforcement ring may be welded to the body.
Alternatively the reinforcement ring may be formed with an inwardly projecting annular rib and the external surface of the body is formed with an annular groove in which the rib is held with a "snap-in" engagement to retain the ring on the body.
In a further arrangement the external surface of the body may be formed with an annular shoulder facing away from the the open end of the body and the reinforcing ring encircles the part of the body between the shoulder and the open end of the body with a rib on the ring engaging the shoulder to retain the ring on the body.
~ 5 ~ l 3l 6q ~?
The ring may project beyond the open end of the body and is formed with an inturned flange spaced from the open end to retaln a collet location in the open end of the body for coupling a tube to the body.
BRIEF DESCRIPTION OF THE DRAWI:NGS
Figure l is a sectional view through an injection mould tool for part forming a coupling body for a tube couplins;
Figure 2 is a similar view to Figur 1 showing the moulded body with the cores of the tooling removed;
Figure 3 shows a further forming operation being carried ouk on the ends of the coupling body whilst still located in the mould of the tooling;
Figure 4 shows the finished coupling body ready for ejection from the mould;
Figure 5 shows various completed tube couplings having coupling bodies formed by apparatus of the form illustrated in Figures 1 ko 4;
Figures 6 and 7 show a modified form of the ~ mould~tooI of Figure l;
; Figure 8~shows the application of:reinforcing ring to the formed end o~ the coupl1ng body; and Figures 9 to 11 shown various further : 25 ~ ~ reinforcement arrangements.:~
:: DESCRIPT ON_OF ~HE PREFERRED EMBODIMENTS
Referring ~irstly to:Figure 1 of the drawings, :: there is shown tooling for injection moulding of a partly formed coupling body 10 in a plastics material such as polysulphone. The body~comprises a central ~: ~: cylindrical portion 11 having~an inner annular rib 12 ::: at its centre and enlarged diameter cylindrical end portlons 13 joined to the central portion by steps 14. The mould tooling comprises a mould body 15 having a:mouId cavity 16 shaped to *orm the outer : surfaca of the cen~ral portion 12 of the mould body ::
1 31 6q62 and adjacent parts of the end portions. 13.
Cylindrical removable cores 17 project into the mould cavity from opposite sides thereof and have reduced diameter spigots 18 at the orward ends thereof shaped to for~ together the inner sur~ace of the mould body. Each core, has at the juncti.on between the spigot 18 and main body 17 an annular recess 19 the inner surface of which forms a continuation of the surface of the spigot 1~3 and the outer surface of which forms a csntinuation of the adjacent mould surface 13. The recesses form the end parts of the coupling body.
After injecting plastics into khe mould to create the coupling body, the cores 17 are extracted once the plastics has set sufficiently to be self supporting whilst still being relatively hot to leave the part moulded coupling body in the mould cavity as shown in Figure 2. It will he seen that end parts indicated at 13a of the coupling body are left unsupported in the mould. Cylindrical forming dies 20 are now inserted in the mould 15 as shown in Figure 3, each die having a kapering end cavity 21 to receive and form the end part 13a of the coupling body tapering the outer surfaces of the coupling body and causing a corresponding taper on the inner surfaces of the coupling body. At the bottom of each taper cavity 21, there is a short cylindrical portion 22 which forms a short cylindrical end at the tapered : end of the body. The cores are then separated from the mould leaving the moulded coupling body in the : mould as shown i~n Figure 4 ready for ejection from the mould.
Figure 5 shows a number of different forms of coupling body which can be manufactured using this technique. 30 indicates a coupling body of straight cylindrical form open ak both ends as manufactured by - 7 - 1316~62 the tooling described above. A modified form of the tooling enables a T shaped coupling body to be created as shown at 31 and a further modified form of tooling enables an elbow form to be created as shown at 32.
The main advantage with this invention is that it reduces considerably the cost o~ manufacture as it is much quicker and easier to provide the recessed end forms shown in this manner within the mould, whilst the component is still in the hot condition.
For large pipe fittings it is possible to produce the recessed final form by the use of collapsible cores, but these are of necessitry more complex and far more costly arrangem~nts. On very small pipe sizad collapsible cores of this type are not practical and other more exp0nsive methods have to be employed.
Figures 6 and 7 show a modified form of the mould tooling described above with reference to Figure 1. The modifications relate to the removable cords 17 in which the outer surface l9a of the recess tapers towards the bottom of the recess instead of being of cylindrical form by an angIe Rl as :indicated on Figure 7 to form the end part of the coupling body moulding with a tapered external surface. A portion 18a of the spigot 18 extending into the recess 19 is also tapered to increase in diameter towards the bottom of the recess 19 to form the inner su~face of the end portion of the moulding : with~a tapered angle R 2 as iIlustrated in Figure ~7. After extraction of the cause 17 the tapered end ~ part of the moulding are post-moulded as described : above with reference to Figure 3.
Referring now to Figure 8 of the drawings, the post-formed moulding is shown before removal from the mould body 15 immediately after retraction of the forming dyes 20. :Tapered rings 40 are then applied - 8 _ 1 31 6q62 to the extexnal surface of the tapered end parts 13a created in the post-~orming operation, the rings being raised to snap into grooves formed in the tapered end parts or being welded or swaged onto the tapexed end parts. The reinforcing ring~ are applied before the post-~ormed end parts have achieved a permanent set or that is before a permanent change in the elastic material of the moulding has taken place e.g. cross linking of a polyethylene plastics material. Reinforcing rings ensure that the tapered end parts are held permanently in the po~t-formed shape and also assist in resisting the loads imposed on the tapered end parts by the tube gripping column that is located in the e~ds of the coupling in use.
Further more elaborate forms of reinforcing members for the moulded coupling bodies are illustrated in Figures 9 to 11 which will now be referred to. In Figure 9, the whole of the end part 13a of the mould is encircled by the correspondingly shaped reinforcing sleeve 41. The outer surface of the moulding 13 is formed with a groove 42 in which an integral rib 43 on the sleeve 41 is a "snap-in"
engagement to hold the sleeve on the end part 13a.
Figure 10 shows a further arrangement in which the sleeve 41 is extended to the stepped shoulder 14 in the coupling body and the rib 43 on the sleeve snaps over the shoulder 41 to retain the sleeve on the end part of the coupling body~ In the arrangements shown in Figure 11 the sleeve 41 has a cylindrical extension 44 which projects beyond the open end of the coupling body and is formed with an inturned end flange 45 which acts to retain collet 46 in the coupling body which locks a tube in the coupling body.
Claims (19)
1. A method of manufacturing a tube coupling body having a throughway to receive a tube from an open end of the throughway to be secured in the coupling body, the method comprising the steps of initially moulding the body with a non-convergent throughway extending to said open end and, whilst the moulding is hot from the moulding operation, releasing at least a part of the moulded body adjacent said open end from the mould and applying a shaped die to the external surface of that end part to re-form said end part with an internal cross-section which reduces towards said open end.
2. A method as claimed in Claim 1, wherein the step of initially moulding the body forms the body with a parallel sided throughway extending to said open end.
3. A method as claimed in Claim 1, wherein the step of initially moulding the body forms the body with a divergent throughway extending to said open end.
4. A method as claimed in Claim 1, wherein the step of re-forming said end parts forms the internal cross-section with a tapered surface which converges towards said open end.
5. A method as claimed in Claim 1, wherein the step of initially moulding the body forms the external surface of the body with a reducing taper towards said open end of the body.
6. A method as claimed in Claim 1, wherein the die has a cavity which is tapered as it extends into the die to form an external taper on said end part of the coupling body and a corresponding internal tapered surface in the end part of the mounlded body to form a cam surface for acting on the resilient arms of a collet to be inserted in the end part of the moulded body for clamping a tube in the body.
7. A method as claimed in Claim 6, wherein the body is moulded in a mould having a cavity shaped to form an external surface of the body and a removable core shaped to form the internal surface of the body, the core having an annular recess to co-operate with the mould cavity in forming an annular end part of the body whereby, after moulding the body, removal of the core exposes the annular part of the moulded body on which said die forming operation is then performed.
8. A method as claimed in Claim 1, wherein a reinforcement ring is applied to the external surface of the annular end part of the body around at least the part of the body containing the internal tapered surface to strengthen the end part of the body.
9. A method as claimed in Claim 8, wherein the reinforcement ring is welded to the body.
10. A method as claimed in Claim 8, wherein the reinforcement ring is formed with an inwardly projecting annular rib and the external surface of the body is formed with an annular groove in which the rib is engageable to retain the ring on the body.
11. A method as claimed in Claim 8, wherein the external surface of the body is formed with an annular shoulder facing away from the open end of the body and the reinforcing ring encircles the part of the body between the shoulder and the open end of the body with a rib on the ring engaging the shoulder to retain the ring on the body.
12. A method as claimed in Claim 8, wherein the ring projects beyond the open end of the body and is formed with an inturned flange spaced from the open end to retain a collet located in the open end of the body for coupling a tube to the body.
13. A method as claimed in Claim 1, wherein the body is formed with a plurality of annular open ends in said moulding operation and each of said end parts of the moulding is released whilst still hot and subjected to said die forming operation to re-form each end part with an internal tapered surface which reduces a cross-section towards the open end thereof.
14. A tube coupling body having a throughway to receive a tube from an open end of the throughway to be secured in the coupling body, the body comprising a pre-formed plastics moulding with a post-formed annular open end part having an internal surface which reduces towards the open end thereof to receive a collet projecting into the open end and having a plurality of resilient fingers engagable with the tapered surface to compress the fingers against a tube extending through the collet to lock the tube in the body.
15. A tube coupling body as claimed in Claim 14, wherein a reinforcement ring as applied to the external surface of the annular end part of the body around at least that part of the body containing the internal reducing surface to strengthen said end part of the body.
16. A tube coupling body as claimed in Claim 15, wherein the reinforcement ring is welded to the body.
17. A tube coupling body as claimed in Claim 15, wherein the reinforcement ring is formed with an inwardly projecting annular rib and the external surface of the body is formed with an annular groove in which the rib is held with a "snap-in" engagement to retain the ring on the body.
18. A tube coupling body as claimed in Claim 15, wherein the external surface of the body is formed with an annular shoulder facing away from the the open end of the body and the reinforcing ring encircles the part of the body between the shoulder and the open end of the body with a rib on the ring engaging the shoulder to retain the ring on the body.
19. A tube coupling body as claimed in Claim 15, wherein the ring projects beyond the open end of the body and is formed with an inturned flange spaced from the open end to retain a collet location in the open end of the body for coupling a tube to the body.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP88302708.8 | 1988-03-25 | ||
| EP88302708 | 1988-03-25 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1316962C true CA1316962C (en) | 1993-04-27 |
Family
ID=8200002
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000594697A Expired - Fee Related CA1316962C (en) | 1988-03-25 | 1989-03-23 | Methods of manufacturing tube coupling bodies |
Country Status (11)
| Country | Link |
|---|---|
| US (1) | US5038455A (en) |
| EP (1) | EP0334648B1 (en) |
| JP (1) | JP2785874B2 (en) |
| KR (1) | KR890014240A (en) |
| AU (1) | AU620853B2 (en) |
| BR (1) | BR8901397A (en) |
| CA (1) | CA1316962C (en) |
| DE (1) | DE68908221T2 (en) |
| IL (1) | IL89726A (en) |
| NZ (1) | NZ228497A (en) |
| ZA (1) | ZA892240B (en) |
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| JPH02288909A (en) * | 1990-03-26 | 1990-11-28 | Canon Inc | Character processing device |
| US5707486A (en) * | 1990-07-31 | 1998-01-13 | Applied Materials, Inc. | Plasma reactor using UHF/VHF and RF triode source, and process |
| US5354530A (en) * | 1993-01-21 | 1994-10-11 | Airtrol Components, Inc. | Pressure fluid stabilized regulator with leakage orifice and method of forming precise molded orifice units |
| DE4421566C1 (en) * | 1994-06-20 | 1995-08-24 | Teves Gmbh Alfred | Plastic piston mfr. |
| US6379069B1 (en) | 1994-12-12 | 2002-04-30 | James Alexander Corporation | Dispenser and process |
| GB9520748D0 (en) * | 1995-10-11 | 1995-12-13 | Imi Norgren Ltd | Releasable push-in tube couplings |
| US5624694A (en) * | 1996-03-18 | 1997-04-29 | Republic Tool & Mfg. Corp. | Mold for making an internally threaded housing |
| GB9618922D0 (en) * | 1996-09-11 | 1996-10-23 | Guest John D | Improvements in or relating to collets for coupling devices |
| US5980230A (en) * | 1997-04-11 | 1999-11-09 | Velcro Industries B.V. | Forming fastener products |
| JP3919043B2 (en) * | 1998-03-09 | 2007-05-23 | 富士フイルム株式会社 | Spool injection mold |
| AUPP864999A0 (en) * | 1999-02-12 | 1999-03-11 | Bishop Manufacturing Technologies Pty Limited | Moulded component and method of manufacture thereof |
| DE19929665B4 (en) * | 1999-06-25 | 2009-07-30 | Sarstedt Ag & Co. | Sample vessel for receiving sample material, such as blood or urine |
| US20060265852A1 (en) * | 2001-01-19 | 2006-11-30 | Victaulic Company | Triple-expanded mechanical pipe coupling derived from a standard fitting |
| DE10112548C2 (en) * | 2001-03-15 | 2003-02-27 | Gabo Systemtech Gmbh | Pipe connection with fitting |
| US6629832B1 (en) | 2001-08-07 | 2003-10-07 | Crum Manufacturing, Inc. | Apparatus for molding an end of an annular article |
| US7354079B2 (en) * | 2002-04-23 | 2008-04-08 | Watts Sea Tech, Inc. | Connector |
| CN100394256C (en) * | 2003-10-14 | 2008-06-11 | 碧理科技有限公司 | Liquid crystal aberration correcting element, and production method therefore |
| US7617950B2 (en) | 2004-05-24 | 2009-11-17 | Colgate-Palmolive Company | Controlling flow from multi-chamber containers |
| NZ539383A (en) * | 2004-05-26 | 2006-11-30 | Guest John Int Ltd | Collet for tube couplings with head made of stronger material than rest of collet |
| US7419251B2 (en) * | 2004-10-29 | 2008-09-02 | Hewlett-Packard Development Company, L.P. | Overmolded tube header |
| FR2877258A1 (en) * | 2004-11-03 | 2006-05-05 | Rz Engineering Soc Par Actions | DEVICE FOR MANUFACTURING BY MOLDING A BELLOW ENVELOPE COMPRISING MEANS FOR MAINTAINING A DEVILABLE CORE AND CORRESPONDING METHOD |
| US20050111900A1 (en) * | 2004-11-30 | 2005-05-26 | Francesca Fazzolari | Ampoule and method of use |
| US7581899B2 (en) | 2004-11-30 | 2009-09-01 | James Alexander Corporation | Dispenser and process |
| US7976234B2 (en) | 2006-04-28 | 2011-07-12 | James Alexander Corporation | Multi-chambered dispenser and process |
| US8100294B2 (en) * | 2007-12-18 | 2012-01-24 | James Alexander Corporation | Container assembly |
| US8910830B2 (en) | 2007-12-18 | 2014-12-16 | James Alexander Corporation | Container assembly |
| US8403178B2 (en) * | 2007-12-18 | 2013-03-26 | James Alexander Corporation | Container assembly |
| EP2463212B1 (en) | 2008-01-29 | 2013-08-07 | James Alexander Corporation | Dispenser |
| US9855675B1 (en) * | 2016-09-20 | 2018-01-02 | RELIGN Corporation | Arthroscopic devices and methods |
| DE102017107756A1 (en) * | 2017-04-11 | 2018-10-11 | Voss Automotive Gmbh | "Plastic connectors and method for its manufacture" |
| CN113733435B (en) * | 2021-07-30 | 2022-10-21 | 西安航天发动机有限公司 | Combined type valve core cold press molding tool and molding process |
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| GB796304A (en) * | 1956-04-16 | 1958-06-11 | Sidney Edward Youthed | An improved method and means for jointing thermoplastic synthetic resin pipes, pipe fittings and the like |
| AT281513B (en) * | 1967-08-21 | 1970-05-25 | Karl Ing Bengesser | Quick coupling |
| US3674292A (en) * | 1969-10-15 | 1972-07-04 | Amp Inc | Tubular connection devices |
| US3929943A (en) * | 1972-10-19 | 1975-12-30 | Du Pont | Process for sealing thermoplastic tube |
| FR2227483B1 (en) * | 1973-04-24 | 1975-08-22 | Legris France Sa | |
| GB1520742A (en) * | 1975-07-30 | 1978-08-09 | Guest J D | Couplings for tubes |
| US4028037A (en) * | 1975-03-17 | 1977-06-07 | The Dow Chemical Company | Tube treating and apparatus therefor |
| NL183053C (en) * | 1975-10-03 | 1988-07-01 | Wavin Bv | COMPOSITE PLASTIC TUBE CONTAINING TWO CONCENTRIC TUBES AND METHOD FOR MANUFACTURING SUCH PLASTIC TUBE. |
| US4018462A (en) * | 1975-10-31 | 1977-04-19 | Hitachi Metals, Ltd. | Pipe fitting |
| US4113829A (en) * | 1976-02-09 | 1978-09-12 | Philips Industries Inc. | Method of forming a bell end on thermoplastic pipe |
| GB1576131A (en) * | 1976-05-13 | 1980-10-01 | Imi Enots Ltd | Tube coupling device components therefor and method for its manufacture |
| GB1599285A (en) * | 1978-05-15 | 1981-09-30 | Imi Enots Ltd | Collets for use in tube coupling device |
| US4345956A (en) * | 1980-04-16 | 1982-08-24 | Phillips Petroleum Company | Method for making a pipe connection or fitting |
| JPS5896512A (en) * | 1981-12-04 | 1983-06-08 | Kubota Ltd | Method of molding receptacle of end of plastic pipe |
| US4525136A (en) * | 1982-01-11 | 1985-06-25 | Rowley William W | Application for forming a plastic tube coupling |
| JPS58138614A (en) * | 1982-02-10 | 1983-08-17 | Kubota Ltd | Molding of plastic tube end socket |
| DE3303434A1 (en) * | 1983-02-02 | 1984-08-02 | Georg 8000 München Seiler | Collar connection, which is sealed and protected against thrust forces, on plastic pipes |
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| US4551292A (en) * | 1984-04-05 | 1985-11-05 | Angiomedics, Inc. | Method for making a catheter with a soft, deformable tip |
| US4664423A (en) * | 1984-06-15 | 1987-05-12 | Rowley William W | Polybutylene tube coupling and method for making it |
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-
1989
- 1989-03-22 EP EP89302887A patent/EP0334648B1/en not_active Expired - Lifetime
- 1989-03-22 DE DE89302887T patent/DE68908221T2/en not_active Expired - Fee Related
- 1989-03-22 US US07/327,308 patent/US5038455A/en not_active Expired - Lifetime
- 1989-03-23 ZA ZA892240A patent/ZA892240B/en unknown
- 1989-03-23 CA CA000594697A patent/CA1316962C/en not_active Expired - Fee Related
- 1989-03-23 IL IL89726A patent/IL89726A/en not_active IP Right Cessation
- 1989-03-23 AU AU31637/89A patent/AU620853B2/en not_active Ceased
- 1989-03-25 KR KR1019890003923A patent/KR890014240A/en not_active Application Discontinuation
- 1989-03-27 BR BR898901397A patent/BR8901397A/en unknown
- 1989-03-27 JP JP1076377A patent/JP2785874B2/en not_active Expired - Fee Related
- 1989-03-29 NZ NZ228497A patent/NZ228497A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| DE68908221D1 (en) | 1993-09-16 |
| US5038455A (en) | 1991-08-13 |
| NZ228497A (en) | 1991-10-25 |
| EP0334648A2 (en) | 1989-09-27 |
| IL89726A0 (en) | 1989-09-28 |
| AU3163789A (en) | 1989-09-28 |
| JPH0248927A (en) | 1990-02-19 |
| ZA892240B (en) | 1990-11-28 |
| DE68908221T2 (en) | 1993-12-23 |
| JP2785874B2 (en) | 1998-08-13 |
| AU620853B2 (en) | 1992-02-27 |
| KR890014240A (en) | 1989-10-23 |
| BR8901397A (en) | 1989-11-07 |
| EP0334648B1 (en) | 1993-08-11 |
| IL89726A (en) | 1992-06-21 |
| EP0334648A3 (en) | 1990-08-01 |
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| Date | Code | Title | Description |
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