GB2188039A - A filling head assembly for filling a flowable medium into a container - Google Patents

Abstract

A filling head assembly comprises a hollow outer housing(3), an inlet(9), an inner member(4) slidably mounted in the housing(3) and resiliently biassed towards a position of projection therefrom, an outer member(5) removably attachable at one end to the projecting end of the inner member(4), and a rod-like member(6) which extends through the assembly and carries a vent passage(28). A hollow nozzle tip(7) having at least one lateral outlet opening(7a) is removably attachable to the rod-like member(6) to seat slidably within and cooperate with the outer member(5). In operation, medium passed into the assembly through the inlet opening(9) is filled into a container by displacement of the outer member(5) and attached inner member(4) against the resilient bias to an extent sufficient to move back the outer end(5a) of the outer member(5) clear of the outlet opening(7a). The arrangement is such that the nozzle tip(7) and/or the outer member(5) can readily be removed from the assembly and replaced by a tip of different size or different arrangement of outlet opening or openings and/or a different size outer member, to modify the assembly for use with a different container or for filling a different flowable material. <IMAGE>

Description

SPECIFICATION A filling head assembly for filling a flowable medium into a container This invention relates to a filling head assembly for filling a flowable medium into a container, suitable, particularly but not exclusively, for filling a liquid medium into a bottle.

Conventional filling head assemblies usually employ a fixed depending hollow tubular member attached at its upper end to a source of liquid to be filled and having a nozzle tip fixed in the lower end thereof, and a sleeve slidably fitting over the tubular member and nozzle.

The sleeve is biassed, by a coil compression spring fitted over the tubular member between an upper shoulder thereof and an upper shoulder of the sleeve, downwardly towards a position in which it covers lateral outlet openings in the nozzle tip. A container is filled from such a conventional assembly by raising the container towards the assembly until the mouth rim of the container engages the lower end of the sleeve with the nozzle tip within the container mouth or neck, and continuing to raise the container to push the sleeve up against its spring bias to uncover the lateral outlet openings in the nozzle tip and allow liquid to flow therefrom into the container.

When the latter is full it is lowered away from the assembly allowing the sleeve to return under the action of its spring bias and cover off and close the lateral outlet openings in the nozzle tip once again.

Such a conventional filling head assembly whilst being relatively simple to construct and operate is not very flexible in use. For example such an assembly has to be tailor made to suit a particular size of container mouth with a specific diameter tubular member and nozzle tip. To change a machine having, say forty such assemblies, over to fill a different size container requires replacement of each assembly by an assembly having the desired new diameter tubular member and nozzle tip which is expensive and time consuming.

This aiso has to be done if a different nozzle tip is required having different lateral outlets to suit the flow characteristics of a different liquid to be filled.

Additionally with such conventional filling head assemblies the biassing or return spring is on the outside of the assembly where it is exposed to dirt, corrosion and other damage requiring frequent maintenance and replacement with consequent increase in expense and loss of use of the assembly during repair. Dismantling the conventional assembly is not easy, requiring totai removal of the assembly from the filling machine, and this makes it difficult and time consuming to clean and service the assembly.

There is thus a need for a generally improved filling head assembly which can more easily be adapted for use with different filiing mediums and different size and type of containers, and which can be more easily cleaned and stripped for service if and when necessary.

According to the present invention there is provided a filling head assembly for filling a flowable medium into a container, including a holiow outer housing having at least one open end and an inlet opening through a wall thereof through which inlet opening medium to be filled can be passed into the housing, a hollow, elongated, open-ended, inner member slidably mounted in the housing to project at one end from said at least one open end of the housing and resiliently biassed towards said position of projection in a direction outwardly of said housing, a hollow, elongated, open-ended, outer member removably attachable at one end to the projecting end of the inner member in longitudinal extension thereof, a rod-like member securable at or adjacent one end to the housing and extending through the assembled housing, inner member and outer member, to terminate at its other end in the region of the outermost open end of the outer member, and a hollow nozzle tip having at least one lateral outlet opening, which tip is removably attachable to said other end of the rod-like member to seat slidably within and cooperate with said outermost end of the outer member so that in operation of the assembly medium passed into the assembly through the outer housing inlet opening may be filled therefrom into a container by displacement of the outer member and attached inner member against the resilient bias to an extent sufficient to move back the outer end of the outer member clear of the at least one lateral outlet opening in the nozzle tip to permit the medium to issue through the lateral outlet opening into a container, and the lateral outlet opening closed again to stop issuance of medium to be filied therefrom by return of the outer member, and attached inner member, under the resilient bias to recover the lateral outiet opening, and the arrangement being such that the nozzle tip and/or the outer member can readily be removed from the assembly and replaced by a tip of different size or different arrangement of outlet opening or openings and/or a different size outer member, to modify the assembly for use with a different container or for filling a different flowable material.

Preferably the holiow outer housing, the hollow inner member, the hollow outer member and the rod-like member are tubular or substantially tubular in form.

Advantageously the nozzle tip is screw threadably attachable to the rod-like member and carries a seal ring around the periphery of the nozzle tip for sealing between the outer member and nozzle tip in the closed returned position of the outer member.

Conveniently the end of the outer member remote from the nozzle tip closing end is dimensioned to fit in a correspondingly dimensioned bore in the inner member and is provided with a shoulder for location against or adjacent to the end of the inner member projecting from the housing, a screw threaded lock ring being provided for fitting over the outer member shoulder and removably engagable with a complementary screw thread provided on the projecting end of the inner member whereby the outer member can be removably attached to the inner member.

Preferably the inner member and outer housing define there between an axially elongated chamber in which is housed a coil compression spring providing the resilient bias.

Advantageously the inner member has a removable peg projecting laterally from a side wall thereof into a corresponding slot provided through the adjacent side wall of the housing, which slot extends in the direction of the longitudinal axis of the housing and inner member, the arrangement being such that the inner member can be removed from the housing by removal of the peg and the degree of permitted sliding movement of the outer member relative to the nozzle tip is determined by the axial length of the slot.

Conveniently the slot opens at its end remote from the outer member into a transverse second slot in the housing to provide an opening of general T shape in which the peg projects, so that when the inner member is retracted into the outer housing to the fullest extent permitted by the cooperating peg and siot, the inner member may be rotated relative to the housing in either direction to a limited extent permitted by the peg travelling along the transverse second slot, whereby the inner member may be releaseably held in the retracted position.

Preferably the inner member, on the outer surface thereof in the region between the spring housing chamber and the inner member end projecting from the housing, has a elongated P.T.F.E. sleeve shrink fitted thereon, which sleeve is reduced in diameter at its outer surface to provide two axially longitudinally spaced larger diameter ring-like bearing surfaces for making slidable bearing contact with the inner surface of the outer housing, the smaller diameter regions of the sleeve accommodating expansion of the sleeve under the effect of heat, without causing the sleeve to expand sufficiently to jam movement between the inner member and outer housing.

Advantageously the inner member carries on its outer surface, adjacent its end remote from the projecting end a ring seal for providing sealing contact with the adjacent inner surface of the outer housing at a position on the other side of the spring housing chamber from the P.T.F.E sleeve.

Conveniently the end of the housing remote from the open end thereof is also and provided with a shouldered aperture there-through to receive the rod-like member and a flange thereon, there being a lock nut releaseably engagable with the shouldered aperture end of the housing to hold the rod-like member fixedly connected to the housing and therebeing a ring seal between the rod like member and shouldered apertured end of the housing.

Preferably the rod-like member has an axial, open-ended, bore there through which opens into a corresponding longitudinal axial bore through the nozzle tip so that the rod-like member bore and nozzle tip axial bore can act as a vent for a container when the nozzle tip is entered in the mouth of a container being or to be filled, and/or for passage of a reduced pressure into the container to assist in filling therein a high viscosity medium.

Advantageousiy the outer housing, inner member, outer member, nozzle tip and rod-like member are made of stainless steel.

Preferably the assembiy includes at least one ring of resilient material dimensioned to fit on the outer tube against the shoulder thereon, with or without a spacer or spacers on the outer member in contact with the resilient material ring to provide a requisite degree of height and resiliency for engagement by an upper part such as a neck rim of a container to be filled to move the outer member to the open position in which the nozzle tip lateral outlet opening is uncovered.

For a better understanding of the present invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is a side view of a filling head assembly according to the invention shown in partiai longitudinal section in a closed position, Figure 1A is a side view of a detail of Figure 1 to an eniarged scale, Figure 2 is a view of a lower part of the assembly of Figure 1 showing a nozzle tip thereof in an open position, Figure 3 is an exploded view, in partially sectioned form, of the assembly of Figures 1 and 2 showing the component parts thereof, Figure 4A is a side view of the assembly of Figures 1 to 3 in a first operative position above an empty container to be filled, Figure 4B is a side view similar to that of Figure 4A showing the assembly and container in a position in which the filling process has begun, Figure 4C is a view similar to that of Figures 4A and 4B showing the assembly thereof and container with the filling process completed, and Figure 4D is a view similar to that of Figures 4A, 4B and 4C showing the assembly in a closed position with a disengaged filled container being moved on for the filling cycie to be repeated.

As shown in the accompanying drawings a filling head assembly of the invention, gener ally referenced 1, is intended for filling a flowable medium into a container 2. Preferably the container 2 is a bottle as illustrated and the medium to be filled therein is a liquid. The assembly 1 may be fitted to in-line or rotary type filling machines and can fili flowable ma terials from low vacuum, gravity assisted va cuum, adjustable and high vacuum, and pres sure vacuum feed systems. Suitable flowable mediums to be filled range from free flowing liquids to viscose creams and the type of con tainer 2 which can be filled may have ex tremely wide mouths such as jars, or very narrow necks such as botties, made from glass, piastics or P.E.T. Easily collapsable plastics containers 2 can likewise be filled with the assembly 1.

As illustrated the assembly 1 basically in cludes a hollow outer housing, a hollow elon gated open-ended inner member 4, a hollow elongated open-ended outer member 5, a rod like member 6 and a hollow nozzle tip 7. The outer housing 3, members 4, 5 and 6 nozzle tip conveniently are made of stainiess steel such as type 316 stainless steel. This pro vides these parts with good resistance to cor rosion, good appearance and easy cleaning properties.

The outer housing 3 preferably is substanti aily tubular in form as illustrated and has at least one open end 8 and an inlet 9 opening through a wall of the housing 3, through which inlet opening 9 medium to be filled can be passed into the housing 3. Conveniently as illustrated in the exploded diagram of Figure 3 the housing may have reduced diameter re gions such as 10 for engagement by a clamp to hold the housing, and thereby the as sembly, in a fixedly depending position of use.

The inner member 4, preferably tubular in form, is slidably mounted in the housing 3 to project at one end 4a from the open end 8 of the housing 3. This inner member 4 is resili ently biassed, such as by means of a coil compression spring 11 towards the position of projection in a direction outwardly of the housing 3 as can be seen in Figure 1.

The outer member 5 is removable attacha ble at one end to the projecting end 4a of the inner member 4 in longitudinal extension thereof, such as by a lock ring 12. The rod like member 6 is securable at or adjacent one end to the housing such as by means of a further lock ring 13 and extends through the assembled housing 3, inner member 4 and outer member 5 to terminate at its other end 6a in the region of the outermost open end 5a of the outer member 5.

The hollow nozzle tip 7 has at least one lateral outlet opening 7a. Any number of such outlet openings 7a can be provided in any shape configuration and arrangement to suit the flow characteristics of the flowabie medium to be filled. For example as shown in Figure 1 there can be a single ring of radial opening 7a in the nozzle tip 7 or two staggered rings of radial opening 7a as shown in Figure 3.

The nozzle tip 7 is removably attachable to the end 6a of the member 6, such as by being screw threadably engagable therewith, to seat slidably within and cooperate with the outermost end 5a of the outer member 5, so that in operation of the assembly medium passed into the assembly 1 through the inlet opening 9 may be filled therefrom into a container 2 by dispiacement of the outer member 5 and attached inner member 4 against the resilient bias of the spring 11 to an extent sufficient to move back the outermost end 5a of the outer member 5 clear of the lateral outlet opening 7a in the nozzle tip 7, as can be seen in Figure 4B to permit the medium to issue through the lateral outlet opening 7a into a container.The lateral outlet opening 7a may be closed again to stop issuance of medium therefrom by return of the outer member 5 and attached inner member 4 under the resilient biassing action of the spring 11 to recover the lateral outlet opening 7a as shown in Figure 4A and Figure 1.

The housing 3, and members 4,5 and 6 are preferably tubular as illustrated. The nozzle tip 7 is screw threadable securable on the end 6a of the rod-like 6 and a seal ring, conveniently a '0' ring 14 is provided about the periphery of the nozzle tip 7 for sealing between the inner surface of the outer member 5 at the outermost end 5a thereof and the nozzle tip 7 in the closed returned position of the outer member as shown in Figure 1 and Figures 4A and 4D.

The inner end 5b of the outer member 5 remote from the nozzle tip closing end 5a is dimensioned to fit in a correspondingly dimensioned bore in the inner member 4 and is provided with the a shoulder 15 for location against or adjacent to the end 4a of the inner member 4 projecting from the housing 3. The screw threaded lock ring 12 is provided to fit over the outer member shoulder 16 in removable screw threaded engagement with a complementary screw thread provided on the shoulder 16 on the inner member 4 to enable the outer member 5 to be removably attached to and removed from the inner member 4.

The lock ring 12 is apertured to a diameter less than that of the shoulder 15 on the outer member 5 to enable it to grip behind the shoulder 15 as shown in Figure 1.

As can be seen specifically from Figure 1 the inner member 4 has a reduced outer diameter end section which defines with the inner surface of the housing 3 an axially elongated chamber 17 in which the spring 11 is housed. The spring 11 acts between an inwardly directed shoulder 18 formed on an inner surface of the wall of the housing 3 and an outwardly directed shoulder 19 formed on the outer surface of the inner member 4. The shoulders 18 and 19 define with the inner surface of the housing 3 and the outer surface of the inner member 4, the chamber 17.

The inner member 4 has a removable peg 20 projecting laterally from a side wail thereof, as can be seen in Figure 1. This peg 20 is removably attached to the inner member 4 in any convenient manner such as by being screw threadably engaged in a threaded lateral blind bore therein. The peg may be removed in any convenient manner, for example by having a head engagable by a screw driver or by an Allen key. The peg 20 projects into a corresponding slot 21 provided through the adjacent side wall of the housing 3. This slot 21 extends in the direction of the longitudinal axis of the housing and inner member so that the inner member 4 can be removed from the housing by removal of the peg 20 and the degree of permitted sliding movement of the outer member 5 relative to the nozzle tip 7 is determined by the axial length of the slot 20.

Advantageously, although not illustrated, the slot 20 may open at its end remote from the outer member 5 into a transverse second slot in the housing 3 to provide an opening of general T shape into which the peg 20 projects. This means that when the inner member is retracted into the outer housing 3 to the fullest extent permitted by the cooperating peg and slot, the inner member 4 may be rotated relative to the housing 3 in either direction to a limited extent permitted by the peg travelling along the transverse second slot so that the inner member may be releasably held in the retracted position clear of the lateral openings 7a in the nozzle tip 7. This affords access to the tip 7 for removal purposes.

The inner member 4 on its outer surface in a region between the chamber 17 and in a member end 4a projecting from the housing 3 has an elongated P.T.F.E. sleeve 22 shrink fitted thereon. This sleeve 22 is reduced in diameter at its outer surface to provide two axially longitudinally spaced larger diameter ring-iike bearing surfaces 23, as shown in Figure 1, for making slidable bearing contact with the inner surface of the outer housing 3. The smaller diameter regions of the sleeve 22 between the bearing surfaces 23 accommodate expansion of the sleeve under the effect of heat without causing the sleeve to expand sufficiently to jam movement between the inner member 4 and outer housing 3.Additionally use of such a sleeve 22 of P.T.F.E. material considerably reduces the friction between the inner member 4 and housing 3 allowing movement of the members 5 and 4 to open.or uncover the lateral opening 7a in the nozzle tip 7 to be carried out easily and with low force depending upon the choice of strength of spring 11 to enable the assembly to be used with easily collapsable low strength containers.

The inner member 4 carries a ring seal 24 preferably an '0' ring seal as illustrated, on its outer surface, adjacent its innermost end 4b for providing bearing contact with the adjacent inner surface of the outer housing 3, at a position on the other side of the spring housing chamber 17 from the P.T.F.E. sleeve 22.

The end of the housing 3 remote from the open end through which the inner member 4 projects is also open and provided with a shouldered aperture 25 therethrough to receive the rod-like member 6 and a flange 6b thereon. As can be seen in Figure 1 the flange 6b overlies the shoulder 25a of the housing 3 and is releasably held thereagainst by means of a lock nut 26 releasably engaged via an internal thread thereon with a corresponding external thread provided around the shoulder 25a of the housing 3. The rod-like member 6 is fixedly attached to its flange 6b in any convenient manner and a further ring seal 27 is carried around a neck portion of the flange 6b for sealing engagement with the adjacent surface of the shoulder 25a. Thus the rod-like member 6 can be releasably fixedly secured to the housing 3.

This rod-like member 6 has an axial, open ended bore 28 as can be seen clearly from Figure 1. The bore 28 opens into a corresponding longitudinal axial bore 29 through the nozzle tip 7, as can be seen from Figures 1 and 3. The end 6a of the member 6 is releasably attached to the nozzle tip 7, preferably by means of an externally screw threaded tubular adaptor 30 fixedly secured to the end 6a, on which screw thread a correspondingly internally screw threaded portion of the bore 29 of the nozzle tip 7 can be releasably engaged. In this way it is possible easily to remove the nozzle tip 7 from the assembly by pushing back the outer member 5 clear of the nozzle tip lateral apertures 7a by means of the cooperating peg 20 and slot 21 and then unscrewing the nozzle tip 7 from the rod-like member 6.

The bore 28 through the rod-like member 6 and communicating bore 29 through the nozzle tip 7 act as a vent for a container being filled when the nozzle tip is entered in the mouth of the container. In this way air displaced from the container by medium being filled therein from the lateral outlet opening 7a can be removed from the container via the bores 29 and 28. Additionally or alternatively, the bores 28 and 29 can be connected to a source of vacuum or pressure such as a low vacuum with or without gravity assistance, a high vaccum or pressure source to assist the filling of different viscosity mediums to the container. In this way liquids as different as tomato ketchup and wine can readily be filled into a container from the assembly of the invention.

At least one ring 31 of resilient material can be provided to fit over the outer member 5 against the flange 15 as shown in Figures 1 and 2. The degree of resiliency and height of this ring 31 can be chosen to provide the right degree of resiliency and height (rubber setting) governing the filling height of the assembly in a container. In other words the depth to which the nozzle tip protrudes into a container during filling can be altered to suit the size of container being filled by appropriate choice of the axial length of the ring 31.

To this end a spacer or spacers, conveniently of C section, can be provided as shown in Figures 4A to 4D between the ring 31 and the shoulder 15 as illustrated or on the nozzle tip side of the ring 31. These spacers 32 can be made of any convenient material, such as metal or plastics. In this way a single standard length outer member 5 can be used with containers of differing neck height and can be used to fill medium into such containers to any desired height therein.

As shown in Figures 4A to 4D of the accompanying drawings the filling head assembly of the invention is simple to operate. As shown in Figure 4A the first stage is the positioning of a empty container below the assembly 1. The container 2 as shown in Figure 4B is then raised until the nozzle tip 7 and outer member 5 enter the container through its open mouth and until the neck rim 2a of the container 2 engages the resilient material ring 31 and displaces the outer tube 5 upwardly to the fullest extent permitted by the cooperating peg 20 and slot 21 thereby uncovering the lateral outlet openings 7a in the nozzle tip 7 and allowing medium to be filled to issue therefrom into the container.When the desired height of material has been filled into the container 2, which usually is when the upper level of the medium in the container reaches the bottom of the nozzle tip 7 as shown in Figure 4C the filled container 2 is automatically displaced downwardly out of contact with the assembly 1 as shown in Figure 4D. This automatic movement may be controlled in any convenient manner such as by means of a pressure sensor acting via the bore 28 in the rod-like member 6 and communicating bore 29 in the nozzle tip. As shown in Figure 4D as the container 2 moves downwardly away from the assembly 1 the spring 11 returns the outer member 5 back downwardly to cover the lateral outlet opening 7a in the nozzle tip 7 thus cutting off flow of filling medium through the assembly.In this closed position as shown in Figures 4A and 4D the peg 20 is in engagement with the lowermost end of the slot 21. As indicated generally by dot-dashed lines in Figure 1 the assembly of the invention may be held in an upright depending position by means of vertical guide rods 33 and a collar assembly 34 releasably attachable around the housing 3 conveniently in the reduced diameter region 10 thereof.

The assembly of the invention is simple in design, has few parts and can be easily dismantled when necessary for cleaning or change of size nozzle tip or outer member 5, although this is not generally required for day to day operation. The outer member 5 can be removed from the assembly by means of the lock nut 12 at the same time as the nozzel tip 7 is unscrewed from the tubular adaptor 30 on the rod-like member 6, with the assembly otherwise remaining in situ. This allows the user of the assembly to change from one size of container to another by changing only two components. In some cases, such as for accommodating a change of medium to be filled only, only the nozzle tip requires to be changed.The setting of the resilient material ring 31 and spacers 32 which control the filling height in a container need not be disturbed or altered when changing the outer member 5 and nozzle tip 7 to a different diameter as similar thickness rings and spacers can be attached to the replacement outer member 5 to the required height.

Thus the filling head assembly of the invention will accommodate a very wide size range of outer member and nozzle tip diameters, for example in the range of from 1.3/16ths of an inch diameter (30.16mm) down to 1/4 of an inch diameter (6.35mm) which allows the assembly to be used for numerous different applications by selection of the correct outer member and nozzle tip diameters. Sliding movement of the inner member 4 in the housing 3 has low friction requirements by the use of a single sliding liquid seal ring 24 and the natural P.T.F.E. bearing sleeve 22. The sleeve 22 preferably is bonded to the stainless steel inner member 4 and is designed to run at varying ambient temperatures up to 100 c (212if) without expanding in such a way as to stop the assembly functioning. The combination of a single seal ring 24 and the P.T.F.E.

sleeve 22 allows the filling head assembly to be opened and closed with the minimum of effort which in turn allows the assembly to be used on low strength plastics bottles.

By placing the spring 11 in the chamber 1 7 between the housing 3 and inner member 4 the spring is protected from contact with dirt or the fluid medium being filled. Additionally the spring is kept away from the flow passages through the assembly for the medium being filled which also reduces obstruction of flow.

Claims (14)

1. A filling head assembly for filling a flowable medium into a container, including a hollow outer housing having at least one open end and an inlet opening through a wall thereof through which inlet opening medium to be filled can be passed into the housing, a hollow, elongated, open-ended, inner member slidably mounted in the housing to project at one end from said at least one open end of the housing and resiliently biassed towards said position of projection in a direction outwardly of said housing, a hollow, elongated, open-ended, outer member removably attachable at one end to the projecting end of the inner member in longitudinal extension thereof, a rod-like member securable at or adjacent one end to the housing and extending through the assembled housing, inner member and outer member, to terminate at its other end in the region of the outermost open end of the outer member, and a hollow nozzle tip having at least one lateral outlet opening, which tip is removably attachable to said other end of the rod-like member to seat slidably within and cooperate with said outermost end of the outer member so that in operation of the assembly medium passed into the assembly through the outer housing inlet opening may be filled therefrom into a container by displacement of the outer member and attached inner member against the resilient bias to an extent sufficient to move back the outer end of the outer member clear of the at least one lateral outlet opening in the nozzle tip to permit the medium to issue through the lateral outlet opening into a container, and the lateral outlet opening closed again to stop issuance of medium to be filled therefrom by return of the outer member, and attached inner member, under the resilient bias to recover the lateral outlet opening, and the arrangement being such that the nozzle tip and/or the outer member can readily be removed from the assembly and replaced by a tip of different size or different arrangement of outlet opening or openings and/or a different size outer member, to modify the assembly for use with a different container or for filling a different flowable material.

2. A filling head assembly according to claim 1, wherein the hollow outer housing, the hollow inner member, the hollow outer member and the rod-like member are tubular or substantially tubular in form.

3. A filling head assembly according to claim 1 or claim 2, wherein the nozzle tip is screw threadably attachable to the rod-like member and carries a seal ring around the periphery of the nozzle tip for sealing between the outer member and nozzle tip in the closed returned position of the outer member.

4. A filling head assembly according to any one of claims 1 to 3, wherein the end of the outer member remote from the nozzle tip closing end is dimensioned to fit in a correspondingly dimensioned bore in the inner member and is provided with a shoulder for location against or adjacent to the end of the inner member projecting from the housing, a screw threaded lock ring being provided for fitting over the outer member shoulder and remova bly engagable with a complementary screw thread provided on the projecting end of the inner member whereby the outer member can be removably attached to the inner member.

5. A filling head assembly according to any.

one of claims 1 to 4, wherein the inner member and outer housing define there between an axially elongated chamber in which is housed a coil compression spring providing the resilient bias.

6. A filling head assembly according to any one of claims 1 to 5, wherein the inner member has a removable peg projecting laterally from a side wall thereof into a corresponding slot provided through the adjacent side wall of the housing, which slot extends in the direction of the longitudinal axis of the housing and inner member, the arrangement being such that the inner member can be removed from the housing by removal of the peg and the degree of permitted sliding movement of the outer member relative to the nozzle tip is determined by the axial length of the slot.

7. A filling head assembly according to claim 6, wherein the slot opens at its end remote from the outer member into a transverse second slot in the housing to provide an opening of general T shape in which the peg projects, so that when the inner member is retracted into the outer housing to the fullest extent permitted by the cooperating peg and slot, the inner member may be rotated relative to the housing in either direction to a limited extent permitted by the peg travelling along the transverse second slot, whereby the inner member may be releaseably held in the retracted position.

8. A filling head assembly according to claim 6 or claim 7 when dependent from claim 5, wherein the inner member, on the outer surface thereof in the region between the spring housing chamber and the inner member end projecting from the housing, has a elongated P.T.F.E. sleeve shrink fitted thereon, which sleeve is reduced in diameter at its outer surface to provide two axially longitudinally spaced larger diameter ringlike bearing surfaces for making slidable bearing contact with the inner surface of the outer housing, the smaller diameter regions of the sleeve accommodating expansion of the sleeve under the effect of heat, without causing the sleeve to expand sufficiently to jam movement between the inner member and outer housing.

9. A filling head asssembly according to claim 8, wherein the inner member carries on its outer surface, adjacent its end remote from the projecting end a ring seal for providing sealing contact with the adjacent inner surface of the outer housing at a position on the other side of the spring housing chamber from the P.T.F.E. sleeve.

10. A filling head assembly according to any one of claims 1 to 9, wherein the end of the housing remote from the open end thereof is also open and provided with a shouldered aperture there-through to receive the rod-like member and a flange thereon, there being a lock nut releaseably engagable with the shouldered aperture end of the housing to hold the rod like member fixedly connected to the housing and therebeing a ring seal between the rod like member and shouldered apertured end of the housing.

11. A filling head assembly according to any one of claims 1 to 10, wherein the rodlike member has an axial, open-ended, bore therethrough which opens into a corresponding longitudinal axial bore through the nozzle tip so that the rod-like member bore and nozzle tip axial bore can act as a vent for a container when the nozzle tip is entered in the mouth of a container being or to be filled, and/or for passage of a reduced pressure into the container to assist in filling therein a high viscosity medium.

12. A filling head assembly according to any one of claims 1 to 11, wherein the outer housing, inner member, outer member, nozzle tip and rod-like member are made of stainless steel.

13. A filling head assembly according to any one of claims 1 to 12, wherein the assembly includes at least one ring of resilient material dimensioned to fit on the outer tube against the shoulder thereon, with or without a spacer or spacers on the outer member in contact with the resilient material ring to provide a requisite degree of height and resiliency for engagement by an upper part such as a neck rim of a container to be filled to move the outer member to the open position in which the nozzle tip lateral outlet opening is uncovered.

14. A filling head assembly for filling a flowable medium into a container, substantially as hereinbefore described with reference to the accompanying drawings.