GB2027171A - Dispensing tap - Google Patents

Abstract

A dispensing tap comprises a body part (11) having a conical bore (12), and engaged therewith a complementarily conical valve sleeve (13) movable axially relative thereto to create a flow passage therebetween. The opposed ends of the flow passage are in fluid flow connection with inlet (25) and outlet (16) passages and displacement means (31) connected with the sleeve are adapted to cause the axial movement thereof. The cone included angle is at most 5 DEG and the length of the sleeve's conical surface is at least one inch (25mm). A supplementary valve (17) is located downstream of the flow passage and comprises a valve member (17b) cooperating with a valve seat (16b) in the outlet passage. The valve member is operatively connected to the displacement means and a lost motion linkage (17a, 13c) between the displacement means and the valve sleeve provides that the supplementary valve member moves from and into contact with the valve seat respectively before and after movement of the valve sleeve upon respectively opening and closing of the tap. The displacement means comprises a valve stem (14) and cooperating cam surfaces (22) on the stem and body part adapted upon relative rotational motion therebetween to move the sleeve axially of itself, pairs of cam surfaces (22c, 22c', 22d, 22d') providing support therebetween at diametrically opposed locations with respect to the tap axis. <IMAGE>

Description

SPECIFICATION Dispense tap The invention concerns a dispense tap, and has more particular reference to a dispense tap for carbonated beverages.

The object of the invention is to provide a dispense tap which is capable of application to the dispensing of beverages of different CO2 contents or delivery pressures.

According to the present invention, there is proposed a dispense tap comprising a body part, a conical bore to such body part, a complementarily conical valve sleeve engageable with such conical bore and movable axially relative thereto to create, upon such movement, a flow passage therebetween, inlet and outlet passages in fluid flow connection with respective opposite ends of the said flow passage, and displacement means operatively connected with the said sleeve and adapted, upon actuation, to effect axial movement thereof, the cone angle of the said bore and valve member being not more than 2T (that is to say the cone included angle being not more than 50) and the length of the conical surface of the valve sleeve being not less than 1 't (25 mm).

According to a preferred feature, a supplementary valve member is provided downstream of the flow passage formed by and between the conical bole and complementarily conical valve sleeve, such valve member being cooperable with a valve seat in the outlet passage from the aforesaid flow passage to prevent fluid flow therethrough, the supplementary valve member being operatively connected with the displacement means and being movable to and from its position of engagement with the valve seat by such means, there being a 'lost-motion' between the displacement means and valve sleeve such as provides forthe movement of the supplementary valve member from its valve seat before axial shift of the sleeve member on opening of the tap and for the movement of the supplementary valve member into engagement with its valve seat after return motion of the valve sleeve on closing of the tap.

According to a further preferred feature, the displacement means includes a valve stem and co-operating cam means on said stem and body part adapted, upon relative rotational motion therebetween, to effect an axial shift of the said valve stem.

According to a still further preferred feature, the co-operating cam means comprise co-operating pairs of cam elements on the stem and body part, the cam elements providing support therebetween at diametrically opposed locations with respect to the axis of the tap.

The invention will now be described further, by way of example only, with reference to the accompanying drawings illustrating one embodiment thereof, and in which: Fig. 1 is a longitudinal section, taken through one embodiment of the invention; Figs. 2 and 3 are sectional views of the lower element of the double cam arrangement whereby the valve stem and valve sleeve are moved axially of the body part on operation of the tap.

Referring now to the drawings, and particularly to Fig. 1 thereof, a tap for dispensing carbonised beverages, for example beer, comprises a tubular body part 11 having a conical bore 12 in the lower part 1 1a thereof to receive a complementarily conical valve sleeve 13 into seating engagement therewith, a valve stem 14 arranged co-axially od the body part 11 and slidably supported in a bearing block 1 5 mounted in the upper part 1 b of the body part 11 for movement in the axial direction of such body part, a tubular outlet nozzle 16 mounted on the body part at the lower end thereof and having an upwardly extending flange 1 6a defining a seating 1 6b for a supplementary valve member 1 7 secured to the lower end of the valve stem 14, first spring means 1 8 between the bearing block 1 5 and-an abutment 19 on the valve stem and against the restraint of which the said stem is axially movable, and a second sprir-lg means 20 between such block and the conical valve sleeve 1 3 against the restraint of which the said sleeve is axially movable, the supplementary valve member 17 being engageable with the valve sleeve 13 to effect axial displacement thereof on axial movement of the valve stem 14 4 in excess of a predetermined distance.

The tap further comprises a cap 21 secured to the valve stem 14 at the upper end thereof, and co-operating cam means 22 on bearing block 15 and the cap 21 adapted, upon relative rotation therebetween, to effect axial displacement of the valve stem 14 and the conical valve sleeve 13 against the restraint of the respective spring means 18, 20.

An inlet port 23 is provided in the wall of the body part 11 between the underside of the bearing block 15 and the upper end of the tubular sleeve member 13 and a lug 24 is secured to such body part in register with the port 23 to define an inlet passage 25.

The body part 11 is of generally cylindrical internal configuration at its upper end, as at 1 2a, to receive the lower portion 1 Sb of the bearing block 1 5 as a free but close fit therein, whilst the lower end is similariy cylindrical, as at 1 2b.

Intermediate the two generaily cylindrical bores, the body part is of conical configuration. The inlet port 23 is in the upper cylindrical part of the bore 12. At its lower extremity the outer surface of the body part is screw-thrnaded, as at 1 C, to receive a clamping ring 27 for securing outlet nozzle 1 6 to the body part, there being a flange I 6d extending outwardly of such nozzle body for abutment with the annular end face of body part 11. An Bring 28 is provided between the nozzle body 1 6c and the bore 1 2b to effect a fluid seal between the outlet nozzle 1 6 and body part 11, and stop means, for example, in the form of a castellated distance piece (not shown) located on the nozzle body 1 6c between it and valve sleeve 13, may be provided to prevent taper locking of latter in the bore 1 2b.

The outer surface of the upper end of the body part will also be screw-threaded, as at 12c.

The body part 11 will ordinarily be of metal such as brass, stainless steel or any other material commonly used in the art.

The valve sleeve 1 3 is of conical outer configuration, and is conveniently moulded from a rigid synthetic plastics material, the outer surface of such sleeve being complementary to the conical part of bore 12.

The upper and lower ends of the sleeve 13 have cyindrical recesses 1 3a 1 3b respectively, there being an inwardly directed flange 1 3c separating such recesses, the upper face of the flange abutting a sealing ring 29, such ring bearing against the surface of the valve stem 14 to effect a seal between the stem and sleeve internally of the latter.

The valve stem 1 4 is cylindrical, the lower end having a reduced diameter thread 14a, to cooperate with the threaded bore of the upper end of an extension 30 to the stem 14, whilst the upper end has a transverse threaded bore 1 4b, to receive the inner end of an operating handle 31 mounted through the cap 21. A peripheral channel 1 4c is provided in the upper part of the valve stem, and more particularly in that part thereof lying within the bearing block 15, to receive a sealing ring 32 for effecting a fluid seal between the stem 14 and the bearing block 1 5.

Bearing block 1 5 is of moulded form, and of stepped outer configuration, flange portion 1 5a limiting engagement of the block 1 5 with the body part 11. A cut out is provided in the annular end face of the body part for co-operation with a complementary dog on the bearing block rotationally to fix such block relative to the body part. A peripheral groove 1 sic is formed in the bearing block in the lower portion 1 5b thereof to receive a sealing ring 33, to provide a fluid tight seal between the block and body part, whilst the flange on the bearing block extending outwardly of such bearing block is held in abutment with the end face of the body part 11 by a second clamping ring.At its upper end the bearing block 1 5 is stepped to receive a part of the cam means 22, such part being mounted on the bearing block.

The supplementary valve member 17 comprises a conical face holding a valve ring 17b, such member forming the upper end of extension 30, and valve ring 1 7b is movable to and from engagement with the valve seating 16b.

An abutment ring 35 is provided within the cylindrical recess 1 3a in the valve sleeve 13, such ring seating against the upper face of sealing ring 29 and serving the two-fold purpose of providing a seating to receive the lower end of the second spring means 20 and of retaining O-ring 29 in position relative to the flange 13c.

The co-operating cam means 22, see particularly Figs. 2 and 3 of the drawings, comprises a first part 22a in abutment with the bearing block 15, as has previously been indicated, and a second part 22b mounted in the cap 21, such parts including two co-axial cam surfaces 22c 22c', 22d 22d' respectively. Cam means part 22b has a radially extending slot for engagement with a corresponding lug at the inner end face of cap 21, thus rotatably to fix the said part in the cap, whilst cam means part 22a is nonrotatably mounted on the bearing block 1 5 by providing complementary structures, for example corresponding flats or similar slot and lug (not shown) therebetween.

In order to assemble the tap, which assembly can readily be effected without the aid of tools, abutment 19, which abutment is conveniently a circlip or some such arrangement engaged with a peripheral groove in the surface of the stem, is placed in position, and abutment ring 35 is arranged co-axially upon the stem. The valve stem is then engaged with the through hole in flange 1 3c of the valve sleeve, and the extension 30 to the stem is applied to such stem. The resultant sub-assemby is then applied to the valve body 11, and spring means 1 9, 20 are arranged co-axially upon the stem.Mounting of the bearing block 1 5 on the free end of the valve stem and the movement thereof axially of the stem against the restraint of the spring means to bring the dog of the bearing block into engagement with the cutout in the end of the valve body 11 will allow the clamping ring to be tightened to hold the bearing block flange in close abutment to the top of the body part 11, relative rotation therebetween being precluded by the co-operating cut-out and dog.

The spring means 18, 20 hold the conical valve sleeve 1 3 in engagement with the complementarily conical bore 12 of the body part and maintain the supplementary valve member 17 in its extended position.

Cam means part 22a is non-rotatably applied to the bearing block, and the completion of the assembly of the upper part of the tap requires only that the cap 21, with cam means part 22b mounted therein, be applied in co-axial relationship with the tap body in an appropriate angular disposition thereon for the through hole in the cap which receives the operating handle to be aligned with the transverse hole 1 4b in the upper end of the valve stem, and that the handle be mounted through the cap with the forward end thereof engaged with such transverse hole.

Assembly of the lower end of the tap is completed by the co-axial location of the outlet nozzle 16 with the lower end of the body part 11 and by the engagement of clamping ring 27 with the body part.

It is to be understood that the various sealing rings will be placed in position upon the relevant part before assembly of the tap.

As will be appreciated, the assembly of the tap as hereinproposed can be effected in a simple and rapid manner and without the need for tools of any kind.

Variations in the assembly sequence set forth are, of course, possible in some instances.

In operation, rotation of the operating handle about the axis of the tap will effect an axial shift of the valve stem due to the action of the cam means. During initial rotation, the supplementary valve member 17 is lifted from the related valve seat 1 6b as the stem moves against the restraint of spring means 1 8, thus to connect the annular space 36 between the walls of the lower cavity 1 3b and the flange 1 6a with the outlet nozzle 16.

On continued rotational movement of the operating handle, further axial shift of the valve stem occurs such as will bring sealing ring 1 7a of supplementary valve means 1 7 into abutment with flange 1 3c of the valve sleeve 13 and thereupon lift the said valve sleeve, thereby opening a conical flow passage between the said sleeve and the opposed conical bore 12 which is in fluid flow connection with, at one end, flow chamber 37, itself connected with inlet port 23, and, at the other end, with annular space 36, which latter space is in fluid flow connection with the outlet nozzle. Accordingly, beverage flowing to the tap via inlet port 23 passes through the tap to pass outwardly thereof via the outlet nozzle.

By suitable angular adjustment of the operating handle, the axial displacement of the conical valve sleeve relative to the body part, and thus the cross-sectional dimensions of the flow passage between the valve sleeve and the valve body, can be varied to suit particular requirements, it being understood that the extent of axial shift will be determined by the extent of angular adjustment in relation to the form of cam surface and that the cross sectional dimensions of the passage will depend upon the extent of axial shift of the valve sleeve in reiation to the cone angle of such sleeve and co-operating bore.

In the embodiment illustrated the cone angle of the mating surfaces of the valve sleeve and conical bore is approximately 12 (to given an included angle of 30), whilst the length of the valve sleeve is approximately 1 Tn (38 mm).

Dimensions of this magnitude have been found to be such as to allow of the satisfactory use of the tap with carbonated beverages delivered at a range of pressures, the degree of opening of the tap being varied to suit the specific requirements of the beverage and delivery pressure.

However, other cone angles and sleeve lengths may be used whilst still providing for linear flow of the beverage, and thereby avoiding undue frothing of the beverage. For example, cone angles of up to 2T (50 included angle), and sleeve lengths of not less than 1" (25 mm) are thought likely to give satisfactory results.

The utilisation of a cam as a means of translating rotation motion into linear motion does provide for the use of a given tap for a range of CO2 pressures, and does, furthermore, give a very smooth operation of the tap. The cam means disclosed also provides uniform support for the valve stem during axial shift thereof, and accordingly avoids upsetting the co-axial relationship between the sleeve and opposed bore, with consequential deleterious effects on fluid flow.

The invention is not restricted to the exact features of the embodiment hereinbefore disclosed, since alternatives will readily present themselves to one skilled in the art.

Thus, for example, whilst it is found preferable, from considerations of cost, to form the tap body part from tubing of constant wall thickness by means of known cold-forming or like methods, such body may, if desired be produced by machining, with consequential modification to the detail of the attachment of, for example, the outlet nozzle to the body part.

As an alternative to the use of a threaded collar for axially locating the bearing block relative to the body, a retaining ring disposed outwardly of the body and co-operable with the block via apertures in such body may be preferred.

If desired, the bottom end of the outlet nozzle may be adapted screw-threadedly to receive a sparkler, whilst the end of the valve stem extension 30 may be formed in a manner other than as shown in Fig. 1 to provide for a creaming action on the beer during dispensing thereof.

Claims (11)

1. A dispense tap comprising a body part, a conical bore to said body part, a complementary conical valve sleeve engageable with said conical bore and movable axially thereto to create, upon such movement, allow passage therebetween, an inlet passage and an outlet passage in fluid flow connection with respective opposite ends of said flow passage and displacement means operatively connected with safd sleeve and adapted upon actuation to effect axial movement thereof, the cone included angle of said bore and sleeve being not more than 50 and the length of the conical surface of said sleeve being not less than 1 inch (25 mm).

2. A dispense tap according to claim 1 comprising a supplementary valve member located downstream of said flow passage.

3. A dispense tap according to claim 2, wherein said supplementary valve member is adapted to co-operate with a valve seat in said outlet passage.

4. A dispense tap according to claim 2 or claim 3, wherein said supplementary valve member is operably connected with said displacement means.

5. A dispense tap according to claim 4 comprising a lost motionlinkage locaPed and providing said operable connection between said sleeve and said displacement means.

6. A dispense tap according to claim 5, wherein said lost motion linkage is adapted to provide that, upon movement of said displacement means from a non-operating position, said supplementary valve member moves from said valve seat before axial movement of said valve sleeve commences.

7. A dispense tap according to claim 5 or claim 6, wherein said lost motion linkage is adapted to provide that, upon movement of said displacement means from an operating position, said supplementary valve member moves into contact with said valve seat after axial movement of said valve sleeve ceases.

8. A dispense tap according to any one of the preceding claims, wherein said displacement means comprises a valve stem and co-operating cam means on said stem and said body part adapted upon relative rotational motion therebetween to move said valve sleeve axially of itself.

9. A dispense tap according to claim 8, wherein said co-operating cam means comprise cooperating pairs of cam elements on said stem and body part, said cam elements providing support therebetween at diametrically opposed locations with respect to the axis of the tap.

10. A dispense tap according to any one of the preceding claims wherein stop means are provided to limit movement of said valve sleeve into said conical bore to prevent taper locking therebetween.

11. A dispense tap substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.