|1.||: Spray dispensing apparatus comprising : a) primary reservoir means for a primary fluid to be dispensed; b) secondary reservoir means for a secondary fluid to be dispensed; c) a spray nozzle to receive said primary and secondary fluids and to spray dispense a mixture of same; and d) fluid delivery means adapted to deliver fluid from both said reservoir means to said spray nozzle; e) said apparatus being in the form of a handheld and handpowered and triggeroperated device; f) and said apparatus having said nozzle and said secondary reservoir means located in an upper portion of the apparatus, and said primary reservoir means being located at least mainly in a lower portion thereof. Apparatus according to claim 1 characterised by said upper portion of said apparatus comprising said nozzle and said secondary reservoir means and an associated trigger, and said lower portion of said apparatus consisting of said secondary reservoir means. Apparatus according to claim 1 wherein said apparatus has a spray head comprising said nozzle, and said trigger is located generally below said spray head, and at least two of said secondary reservoirs are provided and are adapted to be mounted on said apparatus so as to be at least partly above said trigger in the normal operating attitude of the apparatus .|
|2.||Spray dispensing apparatus comprising : a) at least one reservoir for at least one fluid to be dispensed; b) a spray nozzle to receive said at least one fluid and to spray dispense same; and c) fluid delivery means to deliver fluid from said at least one reservoir means to said spray nozzle .|
|3.||Apparatus according to claim 4 characterised by said apparatus being in the form of a handheld and hand powered and triggeroperated device.|
|4.||Apparatus according to claim 5 characterised by said apparatus having said nozzle and said secondary reservoir means located in an upper portion of the apparatus and said primary reservoir means being located at least mainly in a lower portion thereof.|
|5.||Apparatus according to any one of the preceding claims characterised by said secondary reservoir means being adapted to be connected to said apparatus by a bayonet or prongtype plugin facility.|
|6.||Apparatus according to claim 7 characterised by rupturable seal means associated with said bayonet or prongtype plugin facility to maintain said secondary fluid within said secondary reservoir in sealed condition until said seal is ruptured in use.|
|7.||Apparatus according to any one of the preceding claims characterised by said secondary reservoir being smaller in fluid volume than said primary reservoir by a factor of at least 2 and preferably of between 4 and 10.|
|8.||Apparatus according to any one of the preceding claims characterised by attachment means for attaching said secondary reservoirs to said primary reservoir when the secondary reservoirs are not in use.|
|9.||Apparatus according to any one of the preceding claims characterised by at least two of said secondary reservoirs, each of said secondary reservoirs having associated therewith its own nozzle and each such secondary reservoir being adapted to be mounted on said apparatus selectively in operative and nonoperative association therewith, the arrangement being such that when the secondary reservoir is in its operative association with the apparatus, the nozzle of the or each of said secondary reservoirs forms the nozzle of the apparatus. Apparatus according to any one of the preceding claims characterised by at least two of said secondary reservoirs, each of said secondary reservoirs having associated therewith its own pump means for said secondary fluid, and each such reservoir being adapted to be mounted on said apparatus selectively in operative and nonoperative association therewith, and in the operative association condition thereof, the pump of the or each of said secondary reservoirs forming the secondary reservoir pump for the apparatus. Apparatus according to any one of the preceding claims characterised by at least two of said secondary reservoirs, each secondary reservoir having associated therewith its own mixing chamber for said primary and secondary fluids, and each such reservoir being adapted to be mounted on the apparatus selectively in operative and nonoperative association therewith, and in the operative association condition thereof, the mixing chamber serving to permit mixing of said primary and secondary fluids in use of the apparatus. Apparatus according to any one of the preceding claims characterised by primary pump means for said primary fluid arranged to deliver said primary fluid to said nozzle, and secondary pump means for said secondary fluid arranged to deliver said secondary fluid to said nozzle for admixture with said primary fluid, said secondary pump means being arranged to be operated in response to operation of said primary pump means, whereby said secondary fluid is not dispensed by said nozzle unless said primary fluid is also dispensed. Apparatus according to claim 14 characterised by said mixing chamber for said primary and secondary fluids being located for delivery of said mixed fluids to said nozzle, said mixing chamber comprising a moveable pumping element for said secondary fluid whereby delivery of said primary fluid to said mixing chamber causes pumping of said secondary fluid into said chamber for admixture therewith. Apparatus according to claim 14 characterised by said mixing chamber being in the form of a pumping chamber having a moveable pumping element and said secondary fluid pumped thereby is delivered for admixture with said primary fluid to a location upstream of the nozzle, other than said chamber. Apparatus according to claim 15 or claim 16 characterised by said moveable pumping element comprising a slidable piston. Apparatus according to claim 15 or claim 16 characterised by said moveable pumping element comprising a moveable diaphragm. Apparatus according to claim 15 or claim 16 characterised by said moveable pumping element comprising a venturi nozzle adapted to allow said primary fluid to flow therethrough to cause suction to be applied to a supply line connected to said secondary reservoir. Apparatus according to claim 19 characterised by resilientlyloaded valve means adapted to inhibit the supply of said primary fluid to said venturi nozzle until a predetermined pressure has been reached in said primary fluid supply. Apparatus according to any one of claims 1 to 15 characterised by said fluid delivery means for said secondary fluid comprising a peristaltic pump. Apparatus according to any one of the preceding claims characterised by the apparatus comprising a spray head having at least two of said secondary reservoirs mounted thereon for selective interchangeable use by means of changeover valve means. Fluid reservoir means for handheld trigger operated spraying apparatus comprising dip tube means for fluid takeup, characterised by said dip tube means being formed integrally with said reservoir means or secured thereto whereby the fluid takeup end of said dip tube is permanently positioned in a defined operative position with respect to the base of the reservoir, and the other end of said dip tube means having associated therewith sealing means for interchangeable sealed cooperation with triggeroperated pump means. A method of handheld spraydispensing comprising selective interchangeable use of two or more quickattach secondary fluid reservoirs in association with a primary fluid reservoir. A method according to claim 22 comprising the step of pumping said secondary fluid into a supply of said primary fluid for admixture therewith. Fluid dispensing apparatus comprising primary and secondary fluid reservoirs characterised by at least two of said secondary reservoirs being provided and adapted to be rapidly operatively interchangeably mountable on said apparatus.|
This invention relates to an apparatus and method for dispensing, particularly but not exclusively to such apparatus and method for spray dispensing. An example of the application of the invention is to hand-held and hand-powered and trigger-operated spray devices of the kind conventionally used for dispensing sprays of such liquids as household cleaning fluids, horticultural treatment fluids, water, cosmetic treatment liquids and the like. Certain aspects of the invention may find application to non-sprayed dispensing of fluids such as beverages, this application being of relevance, for example, to domestic drinks-dispensing machines. However, the principal application of the invention is to trigger-operated spraying devices of the kinds mentioned above.
A problem that arises in relation to known spray dispensing devices is lack of versatility. In order to change from dispensing one liquid to another, there is a need to change over the entire spray dispensing apparatus, including the trigger mechanism, liquid take-up tube, spray nozzle and associated structures from one fluid reservoir to another. This entails disconnection, usually by means of a screw- threaded device, manual disengagement of the apparatus, re¬ insertion of the dip or take-up tube and a reconnection of the apparatus by a reversal of the above operations. This procedure also gives rise to cross-contamination leading to a requirement for purging. Also,this procedure is sufficiently inconvenient to render the operation unacceptable, and users tend to purchase one entire set of apparatus for each application. Despite the modest cost of such equipment, this represents limitation on the use of such devices, and some improvement in versatility is clearly needed by the market.
There is disclosed in US patent number 5,152,461 (Proctor) a hand operated sprayer with multiple fluid containers. A trigger device draws fluid out from at least two containers, mixes the fluid in a desired concentration or ratio and expels the mixture of fluid out of a nozzle. A metering device is provided for variably controlling the ratio of the fluids being mixed. This device however is little if any more convenient than conventional devices, being excessively large due to the use of multiple large liquid containers. Moreover, where one or more of these contains a concentrated liquid, the device is dangerous, due to the risk of neat concentrate being dispensed. Additionally, where it is desired to change from the fluid or fluids available currently in the device to another such fluid or fluids, the change-over operation is little if any more convenient than with a conventional hand-held trigger-type sprayer. The device is also complex and costly.
An object of the present invention is to provide an apparatus and method for dispensing, particularly for spray dispensing, offering improved versatility in operation, and/or improved ease of change-over between fluids to be dispensed, and/or one or more other improvements in relation to matters discussed above, or generally.
According to the invention there is provided apparatus and method for dispensing as defined in the accompanying claims.
In an embodiment of the invention there is provided spray dispensing apparatus, and a corresponding method, comprising primary reservoir means for a primary fluid to be dispensed, secondary reservoir means for a secondary fluid to be dispensed, a spray nozzle to receive and spray-dispense a mixture of said primary and secondary fluids simultaneously, and fluid delivery means adapted to deliver fluid from both
said reservoir means to said spray nozzle.
In the described embodiment, the spray dispensing apparatus is in the form of a hand-held and hand-powered and trigger-operated device.
In an alternative embodiment of the invention, in place of a spray nozzle there is provided a fluid dispensing outlet through which a mixture of the primary and secondary fluids can be dispensed, ultimately into a beverage container. Otherwise, the dispensing apparatus is generally as described herein.
Also in the described embodiment, the dispensing apparatus has a spray head comprising the nozzle, and the trigger is located generally below the spray head. At least two of the secondary reservoirs are provided and are adapted to be mounted on the spray head so that they are at least partly above the trigger in the normal operating attitude of the apparatus. In other words, the secondary reservoirs are selectively mounted on the spray head, not in the normal location for the primary reservoir ie in the lower portion of the apparatus and below the spray head, but in the unconventional location of in the upper portion of the apparatus and generally on top of the spray head, or level with it, or on top of it and somewhat behind it. By virtue of this location of the secondary reservoir, there is provided convenience of mounting and location, together with convenience for admixture of the primary and secondary fluids, in the manner described below. In this way there is avoided the need to draw up liquid from the secondary reservoir by means of a dip tube in the manner of the prior art.
Also in the embodiment, the secondary reservoir means is adapted to be connected to the apparatus by a bayonet or prong-type plug-in facility. In this way, rapid connection
and disconnection can be achieved so that rapid and easy interchange of the secondary reservoirs can be likewise achieved.
In the described embodiment, the bayonet connection means is provided with a tamper-evident foil, or the equivalent, to seal the receptor for the bayonet element prior to connection. The bayonet or plunger is provided on the assembly which includes the primary reservoir and pierces the seal on first use. Prior to connection of the secondary reservoir means to the apparatus, both units are sealed. When the bayonet or plunger is withdrawn after a period of use, it is automatically wiped as it is withdrawn from the other (or female) portion of the connector, so as to prevent drips.
Likewise in the embodiment, the bayonet or prong-type connector operates so as to open automatically the flow of primary fluid towards the nozzle for admixture with the secondary fluid. Valve means prevents fluid flow in the event of incomplete or incorrect connection.
The size of the secondary fluid reservoir is smaller than that of the primary fluid reservoir by a factor of at least 2, and preferably of from 4 to 10. Thus, a typical application of the invention is to spraying material in which the primary reservoir contains a diluent and the secondary reservoir contains a highly concentrated cleaning or other agent. In certain embodiments, means is provided for attaching the secondary reservoirs to the primary reservoir when not in use. The secondary reservoirs may be arranged to be stored effectively within the envelope of the primary reservoir, being attached to the outside of the latter, for example by clip means. In this way an extremely convenient means is provided for storing the secondary reservoirs whereby they do not interfere with normal use of the apparatus and yet
are instantly available for interchangeable use.
Further in the described embodiments, each of the secondary reservoirs has associated therewith its own nozzle, together with its own secondary fluid pump means and its own mixing chamber for the primary and second fluid. Thus, each reservoir is adapted to be mounted on the apparatus selectively in an operative and non-operative association therewith. In its operative mode or association, the nozzle of each respective secondary reservoir forms the operative nozzle of the apparatus. Likewise, the pump means for the secondary fluid of each secondary fluid reservoir serves to pump the secondary fluid from the secondary fluid reservoir to be dispensed through the nozzle after admixture with the primary fluid in the mixing chamber. In this way numerous technical advantages and simplifications are provided over alternative arrangements, these including complete avoidance (by the use of dedicated spray nozzles) of the problem of fluid carry-over between successive dispensing operations. Also, by providing each secondary reservoir with its own pump there is avoided the need for pump-priming and associated uncertainty of initial spraying upon commencing use. Additionally, by providing a mixing chamber associated with the secondary reservoir, for the primary and second fluids, the safety feature is added that (where the secondary fluid is a highly concentrated treatment agent to be diluted by the primary fluid) , the risk of escape of the concentrate is greatly reduced by the fact that it is the diluent which is transferred to the concentrate, rather than vice versa.
In the embodiments, the arrangement provided for pumping the secondary fluid for admixture with the primary fluid is such that the secondary pump means is arranged to be operated in response to operation of the primary pump means, whereby the second fluid is not dispensed by the nozzle unless the primary fluid is also dispensed. Thus, in accordance with
this principle, a mixing chamber for the primary and secondary fluid is provided and is located for delivery of the mixed fluids to the nozzle. The mixing chamber comprises a moveable pumping element for the secondary fluid whereby delivery of the primary fluid to the mixing chamber causes pumping of the secondary fluid into the chamber for admixture therewith. The moveable pumping element comprises in one embodiment a slidable piston and in another embodiment a moveable diaphragm. These arrangements lead to several technical advantages including the safety aspects of secondary fluid dispensing only in response to primary fluid presence. Also, the relative proportions of the two fluids mixed can be adjusted by adopting the requisite dimensions in the construction of the relevant parts of the pumping mechanism. Moreover, at least in the piston pumping embodiment, as the piston retracts, the secondary fluid behind it is pushed into the mixing chamber via a non-return valve, and this ensures thorough mixing. The non-return valves are provided in the form of flexible cup seals in the piston and rod seal. Moreover, in the embodiment, continuous dispensing of the secondary fluid occurs during the pumping phase of the cycle and the large mixing chamber volume and its swirl effect give good mixing of the concentrate and the diluent. In the at- rest position of the piston, it closes off the concentrate supply, and likewise the diluent and concentrate mixture to the nozzle. By pre-loading the piston to its at-rest position, a pre-pressurisation operating characteristic is provided to produce drip-free delivery.
In the embodiments employing a venturi device for causing admixture of the primary and secondary fluids, a venturi nozzle is adapted to allow the primary fluid flow to cause suction to be applied to a supply line connected to the secondary reservoir. A resiliently loaded valve means inhibits supply of the primary fluid to the venturi nozzle until a predetermined pressure has been reached in the primary
fluid supply. As a result, a pressurization stage is produced which causes the venturi to be activated only when there is sufficient pressure to produce fluid velocity and a corresponding pressure drop requisite for the necessary mixing effect. The venturi produces continuous delivery of the secondary fluid for good mixing with the primary fluid. Moreover, when the primary fluid flow stops, the secondary fluid delivery is automatically shut-off.
Embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which :-
Fig 1 shows a circuit diagram of a first embodiment of the apparatus comprising primary and secondary reservoirs, associated pumps, valves and the spray nozzle;
Fig 2 shows, on a larger scale, a section through a bayonet coupling provided between two portions in the apparatus of Fig 1, Fig 2 showing the two portions in their connected condition;
Fig 3 shows the coupling of Fig 2 in its disconnected position;
Figs 4, 5, 6 and 7 show perspective views of alternative systems for mechanically clamping the two portions of the apparatus of Figs 1 to 3 ;
Figs 8 and 9 show side elevation views of the apparatus of the preceding figures showing, respectively, a secondary reservoir in its in-use position and detached from its in-use position, these figures also showing the storage arrangements for three alternatively-mountable secondary reservoirs.
Figs 10 and 11 show, in view similar to those of Figs 8 and 9, alternative mounting arrangements for the secondary reservoirs;
Figs 12 and 13 show a further alternative arrangements for mounting secondary reservoirs;
Figs 14 and 15 a still further arrangement for mounting
Figs 16 and 17 show sectional views through two embodiments of a secondary reservoir employing, respectively, a collapsible bag within the rigid reservoir, and a semi- permeable disc to admit air to the rigid reservoir.
Fig 18 shows a disc or flap valve assembly for'use in the embodiment of Fig 17 in place of the semi-permeable discs;
Fig 19 shows a circuit diagram and associated elevation view of a further embodiment of the apparatus having a mechanical drive for the pump of the secondary reservoir coupled to the corresponding mechanical drive for the pump of the primary reservoir;
Figs 20 and 21 show longitudinal sectional views through a mechanically-driven twin chamber mixing chamber assembly incorporated into the secondary reservoir or pod assembly of Fig 19 or of a further embodiment, wherein pumping of the secondary fluid and mixing of the same with the primary fluid is mechanically energised;
Fig 22 shows a circuit diagram and corresponding side elevation view of an embodiment in which the secondary pump is driven by delivery of primary fluid to the mixing chamber, as in Figs 1 and 23 to 28;
Figs 23, 24 and 25 show a diaphragm pump embodiment in three stages of its operation;
Figs 26, 27 and 28 show a piston pump embodiment, likewise in three stages of its operation;
Fig 29 shows a further embodiment incorporating a venturi - operated mixing system;
Fig 30 shows on a larger scale a cross-section through the venturi pumping and mixing system of the embodiment of Fig 29;
Figs 31 to 34 show details of an elastomeric valve and pump assembly for use in a further embodiment, Figs 31A and 31B being sections in Fig 31 on the lines AA-BB dashed respectively, and likewise Figs 32A and 32B in relation to Fig 32;
Figs 33 and 34 show further alternative cross sections on the line B-B' in Figs 31 and 32 respectively;
Figs 35 to 39 show side elevation views of a peristaltic pumping system in various stages of its operating sequence;
Fig 40 shows a further embodiment in which four secondary reservoirs are simultaneously mounted on the spray head for selected operation;
Fig 41 and 42 show modifications of the embodiment of Fig 40; and
Figs 43 and 43A show vertical sectional and horizontal sectional views (the latter being on the line A-A in Fig 43) through a secondary reservoir suitable for use in the preceding embodiments and illustrating the construction of the dip tube and associated components.
As shown in Fig 1, spray dispensing apparatus 10 comprises a primary fluid reservoir 12 containing a primary fluid 14, and a secondary fluid reservoir 16 containing a secondary fluid 18.
A spray nozzle 20 delivers a spray 22 comprising a mixture of the fluids 14 and 18.
A trigger 24 pivoted at 26 to the housing of apparatus 10 (not shown) is connected at 28 to a piston rod 30 and its corresponding piston 32 which has a return spring 34.
Piston 32 slides in a cylinder 36, and the assembly constitutes a pump 38 for the primary fluid 14.
There is provided, likewise, a pump 40 for the secondary fluid 18. Pump 40 comprises a piston 42, a return spring 44, a cylinder 46 and a piston rod 48.
The headside chamber 50 of cylinder 46 also constitutes a mixing chamber for the primary and the secondary fluids 14
and 18 respectively. It also constitutes an actuating chamber for piston 42, and the rodside chamber 52 of cylinder 46 is connected by fluid lines 54 and 56 to headside chamber 50 and secondary reservoir 16 through non-return valves 58 and 60 respectively.
Likewise, headside chamber 50 is connected by fluid line 62 through non-return valve 64 to headside chamber 66 of cylinder 36, and onwards via fluid lines 68 and non-return valve 70 to primary reservoir 12.
Headside chamber 50 is connected via fluid line 72 and non-return valve 74 to nozzle 20. Valve 74 is also a pre- pressurisation valve serving to ensure that spraying does not commence until there is sufficient pressure to produce the requisite spray discharge pattern
There is shown at 76 an indication of a coupling which may be constituted by a bayonet coupling as described below and illustrated in Figs 2 and 3.
The apparatus of Fig 1 operates as follows. Primary fluid 14 is pumped by primary pump 38 to headside mixing chamber 50. Piston 42 moves leftwards, thereby pumping secondary fluid 18 into chamber 50 through valve 58 and mixing it with primary fluid 14 prior to discharge via nozzle 20.
Coupling 76 is shown in Figs 2 and 3. Trigger 24 and other parts of the apparatus are indicated in the embodiments of Figs 8 to 15. As indicated in these latter figures, each set of spray apparatus 10 comprises a series of interchangeable secondary reservoirs 16, each reservoir being constructed as a unit or assembly or "pod" 78, which comprises a reservoir 16, an associated nozzle 20, secondary fluid pump 40 and mixing chamber 50.
Thus, in this embodiment, the apparatus 10 has a spray head 80 which comprises the nozzle 20 and the associated other portions of pod 78. Trigger 24 is located generally below the spray head 80, being pivoted thereto at 26. The series of 4 secondary reservoirs 16 are adapted to be mounted individually on apparatus 10 so as to lie at least partly above said trigger in the normal operating attitude of apparatus 10.
As shown in Figs 2 and 3, coupling 76 connects pod 78 to the remainder of apparatus 10, which will be conveniently called the "trigger pump unit" 82. Thus, connecter 76 is a bayonet or prong-type plug-in facility comprising a plunger or bayonet element 84 which is spring-loaded outwardly by compression spring 86 acting on an end plate 88, which can seal on its other side against a seat 90 of polymeric sealing material. A similar annular seat 92 of such material is provided at 92 to receive the female portion 94 of the bayonet coupling 76. Bayonet element 84 has axial and radial drillings 96 and 98 respectively, to permit fluid communication therethrough for the purposes to be described.
Rupturable seal means 100 is provided in association with the bayonet coupling 76 to maintain the coupling fluid-tight until it is ruptured in use. Seal 100 is in the form of an adhesively or heat-sealably-secured and fluid-tight plate or diaphragm which can be readily ruptured by the pointed end 102 of bayonet element 84.
Within female portion 94 of coupling 76 there is provided a spring-loaded ball 104 which co-operates with a valve seat 106 so as to seal automatically this portion of the coupling when the two parts are disengaged. Ball 104 is loaded by spring 108.
Fig 2 shows the fluid path 110 when coupling 76 is made and primary fluid can pass through the coupled assembly.
As shown, fluid path 110 extends around end plate 88 which has been disengaged from its seat 90, through axial drilling 96 and radial drillings 98, and leads to mixing chamber 50, as shown in Fig 1.
The rupturable seal means 100, being in the form of a tamper-evident foil or equivalent sheet material, safeguards the user against unauthorised use of the pod 78. Upon disconnection as shown in Fig 3, ball 104 seats on valve seat 106 under the action of spring 108 and end plate 88 seals on seat 90, whereby both portions of coupling 76 are fluid-tight upon disconnection. Moreover, bayonet element 84 itself is effectively "wiped" dry as it is withdrawn through ruptured seal 100 and associated aperture 112 in housing 94.
Turning now to the embodiments of Figs 4 to 7, these show alternative simple mechanical coupling systems for actually mechanically connecting portion 94 of pod 78 with the trigger pump unit 82.
Thus, as shown in Figs 4 and 5, housing portion 94 may be provided with a bayonet element 114 adapted to co-operate with an internal profiled recess 116 adapted to complement and cooperate with element 114. A similar formation 114 and a corresponding recess 116 are provided at a diametrically opposed position on the assembly.
In the embodiment of Figs 6 and 7, fixed and hinged plastic clips 118 and 120 are provided on the upper end of trigger pump unit 82 to cooperate with complementary recesses 122 in housing portion 94. Clip 118 is fixed and clip 120 is resiliently mounted whereby ready manual engagement and disengagement can be achieved.
Turning now to the embodiments of Figs 10 to 15, these show variations on the embodiment of Figs 8 and 9 in which
different locations and sizes and methods of mounting the secondary reservoirs 16, or pods 78 are provided.
In the embodiment of Figs 8 and 9, the pods 78 are located on the primary reservoir 12 by a simple clipping action utilising moulded plastic thumb cut-outs 124 on the pods 78 and which cooperate with the adjacent profile of primary reservoir 12 for mounting purposes. As shown in Fig 9, the external profile of the primary reservoir 12 is formed with relieved portions 126 whereby the pods 78 are conveniently contained within the external profile of the assembly.
In the embodiment of Figs 10 and 11, the pods 78 are mounted in upright positions by cooperating with complementary formations 128 provided on the external surface of primary reservoir 12.
Figs 12 and 13 show a further variation in which the pods 78 are adapted to be located and mounted when not in use on the tapering neck portion 130 of primary reservoir 12, for removal and mounting on the assembly, as in the other embodiments.
The further variation shown in Figs 14 and 15 illustrates the use of different sizes of pods 78 both in their mounted and non-operative position as seen in Fig 14 in relation to the upright pods, and in Fig 15 where the larger pod 78 is shown mounted on the spraying head of the apparatus 10.
In the embodiments of Figs 10 to 15, it will be noted that these pods 78 may be mounted not only in recessed portions of the primary reservoir so as to lie within the external envelope of the latter, but also they may be simply attached to the outside of reservoir 12, or indeed the pods may be attached to the upper portion of the primary reservoir,
which forms part of the hand grip of the apparatus 10. A range of pods sizes can be accommodated.
Summarising therefore in relation to Figs 8 to 15, it will be seen that there have been disclosed modifications wherein the spray head 80 of the apparatus is capable of accepting different sizes and shapes of pods 78 or secondary reservoir. Moreover, the pods can be attached to the primary reservoir of the apparatus and thus stored when not in use in a variety of locations including the hand grip region of the apparatus and the lower region of the primary reservoir 12. Indeed, as suggested in Fig 9, the pods 78 could be stored within space actually created within the reservoir 12, by providing the relieved portions 126 thereof as actual outwardly-opening recesses provided solely to receive the pods. This would of course reduce the fluid capacity of reservoir 12, but such might well be acceptable for certain applications, particularly where high volume of diluent is not required.
Mounting all the secondary reservoirs or pods on the primary reservoir or diluent bottle, particularly at a location in the lower region thereof serves to lower the centre of gravity of the assembly and thus increase the stability of the spraying assembly. This offsets the raising of the centre of gravity caused by mounting the secondary reservoir, or concentrate pod and its associated equipment including valves in the upper region of the assembly.
Turning now to the embodiment of Figs 16 and 17, this shows two general constructions of the secondary reservoir 16 itself. Thus, in Fig 16 reservoir 16 comprises an external generally rigid moulded plastics housing 132 defining the external envelope of the reservoir, and having within it a flexible bag 134 to hold and contain the fluid 18 of reservoir 16.
Thus, as indicated in Fig 16, bag 134 can expand and contract within housing 132 according to its state of filling. In order to allow the bag to contract as fluid passes out of the system through the neck 136 of reservoir 16 there is provided an air bleed hole 138 to admit air.
In the embodiment of Fig 17 which does not utilise a bag 134, but simply allows the fluid 18 to fill the housing 132, there is provided a semi-permeable disc 140 to permit air to enter the housing without the risk of fluid leaking out.
In the embodiment of Fig 18, in place of the semi permeable disc 140, there is provided a disc valve 142 wherein a flap valve element 144 cooperates with aperture 146 provided in a support disc 148, the aperture being connected via a further support disc 150 and opening 152, to the air bleed hole 138. The flap valve 142 admits air while preventing fluid return. The offset location of opening 146 inhibits tampering with the reservoir 16.
Summarising therefore in relation to the features of the embodiments shown in Figs 16, 17 and 18, the position is as follows. In Fig 16, the provision of a flexible bag or fluid containment element capable of collapsing or reducing in size as fluid is withdrawn from it enables fluid to be pumped out of the secondary reservoir 16 or pod 78, while conveniently containing the fluid at other times, without the need to resort to an upright reservoir structure with a dip tube as is conventionally the case and as is used in the case of the primary reservoir 12. Accordingly, this feature relates closely to the provision of the pod and secondary reservoir at a location generally above the remainder of the apparatus, while still feeding fluid for admixture with the primary fluid. The provision of an external housing or structure 132 for reservoir provides external protection for the flexible fluid containment bag 134.
In the embodiment of Figs 17, similar considerations apply, but a different approach to the necessary admission of air into housing 132 has been adopted by means of the air bleed valve 140, and likewise in the case of the flap valve 142 of Fig 18, this latter being usable simply in place of the air bleed valve 140 of Figs 17, and in substantially the same manner.
Turning now to the embodiment of Fig 19, it will be seen that this corresponds to the system of Fig 1 and the previous embodiments, except in one main respect. Therefore, in Fig 19 parts corresponding to those of the preceding embodiments are given the same reference numerals and will not be described further, except as necessary.
In the embodiment of Fig 19, the main difference from the preceding embodiments lies in the method of driving secondary pump 160. In this embodiment, instead of utilising the primary fluid or diluent to drive the pump, there is provided a mechanical link 162 for this purpose. Thus, a simple mechanical drive is taken from the trigger 24 by means of an upstanding drive element 164 which directly engages a pivoted drive member 166 connected to the piston rod 168 and piston 170 of secondary pump 160. In an alternative embodiment (not illustrated) the mechanical drive proceeds directly from drive element 164 and trigger 24 to piston rod 168.
Piston 170 has a return spring 172.
Fluid lines and non-return valves are provided, generally as in the preceding embodiments. However, in this case, the pre-pressurisation valve 174 (corresponding to combined pre- pressurisation and a non-return valve 74 in Fig 1) is shown on the main body or non-pod side of the coupling 76. Alternatively, the valve 174 may be mounted on the pod 78.
In the embodiment of Fig 19, the pods 78 are shown inserted into storage recesses 176 corresponding to the recesses 126 in Fig 9 and provided at the rearside of primary reservoir 12.
With the above-described modifications, the embodiment of Fig 19 functions substantially as described above in relation to the preceding embodiments, except that piston 170 of secondary pump 160 is directly mechanically actuated instead of being actuated by pressure of the secondary fluid or diluent 14.
In this Fig 19 embodiment, the output of secondary fluid pump 160 is mixed with the primary fluid from pump 38, not in a mixing chamber forming part of the secondary pump, but at a T-junction mixing unit downstream of the nozzle 20. The mixing chamber arrangement may alternatively be employed.
It is to be understood that, generally speaking the embodiments described herein are intended to be used in a system in which the individual secondary reservoirs or pods provide sources of treatment fluid in highly concentrated form and a common diluent fluid is provided in primary reservoir 12, thereby enabling a wide variety of tasks to be accomplished.
In the embodiments of Figs 19, 20 and 21 the secondary pump is mechanically driven, as described above in relation to Fig 19. In the embodiments of Figs 22 to 28, there is employed a fluid drive for the secondary pump, thus differing from the embodiment of Figs 19 to 21. The general arrangement of the apparatus for each of these two types of embodiment is shown, respectively, in Figs 19 and 22 in which, as previously, the relationship between the circuit diagram and the actual hardware is indicated. Figs 20 and 21 show on a larger scale the mode of operation of the mechanically-
actuated pumping system for the secondary fluid, or concentrate, of Fig 19. Figs 23, 24, and 25 show an alternative embodiment of pump for the secondary fluid, utilising a diaphragm. Figs 26, 27 and 28 show a piston pump. These two variations (Figs 23 to 25 and 26 to 28) can be considered as options in the system of Fig 22, which shows a piston in the secondary fluid pump. It is to be understood that the piston may be replaced by the diaphragm system of Figs 23 to 25 when so desired.
In the system drawing of Fig 22, the parts correspond to those of Fig 1 (the circuit diagram) and Fig 8 (the general arrangement of the spray apparatus 10) and Fig 19 (the mode of storage of the pods 78) . Therefore, the parts seen in Fig 22 have been numbered accordingly and will not be further described, except where necessary.
Reverting therefore to Figs 20 and 21, these show on a larger scale one embodiment of the secondary pump 160 of Fig 19, comprising a cylinder 180, a piston 182 slidable therein, and a piston rod 184. Piston rod 184 is actuated mechanically in the manner indicated, for example, at 164, 162 and 166 in Fig 19.
Inlet ports 186 and 188 for the primary and secondary fluids are both provided in the rodside chamber 190 of the piston and cylinder assembly, and there is provided the discharge or outlet port 192 in the headside chamber, leading to nozzle 20.
In this embodiment, there is provided an improved facility for mixing of a primary and secondary fluids within the piston and cylinder assembly 180, 182, which thus constitutes a mixing chamber, as previously.
The general mode of operation of the mechanically-driven
piston and cylinder assembly is as follows. Leftward movement (arrow 191) of piston 182, produced by the mechanical drive draws both primary and secondary fluids into rodside chamber 190, and simultaneously causes o ward discharge of previously mixed primary and secondary fluids in headside chamber 193, through outlet port 192 to nozzle.
Return movement of piston 182 under the control of the mechanical drive is shown in Fig 21 at arrow 195. As a result of such return movement of the piston 182, the mixture of fluids present in rodside chamber 190 is caused to pass around the circumference of piston 182, the latter having a one-way flow flexible piston sealing lip 194. The lip 194 permits the fluids to pass as indicated at 196, thereby producing enhanced mixing of the fluids.
Retraction of piston rod 184 is achieved by the mechanical drive indicated in Fig 19. Such return movement may make use of the return spring 172 indicated in Fig 19.
Other than as described above, this embodiment functions generally as the preceding embodiments.
Turning now to the embodiment of Figs 23 to 25, there is shown in these figures a diaphragm pump to be substituted for the piston pumps of the preceding embodiments. The diaphragm pump 200 is located closely adjacent spray nozzle 20, in the manner of the preceding embodiments. The pump housing 202 provides an inlet 204 for primary fluid or diluent. An inlet 206 is likewise provided for the secondary fluid or concentrate.
A first diaphragm 208 serves to define one side of a mixing chamber 210 to which primary fluid 14 is admitted via an annular passage 212 (constituting a mixing chamber) and inlet ports 214.
In a manner similar to that of the piston pump embodiments, first diaphragm 208 moves in a pumping direction under the pressure of the primary fluid (leftwards as seen in Figs 23 to 25) . This applies thrust to a thrust rod 216 having a concave diaphragm support dish 218. Leftwards movement (as seen in Fig 23) of rod 216 causes flexure of a second diaphragm 220. This movement is shown by arrow 222 in Fig 24, and the corresponding pumping action of second diaphragm 220 on the secondary fluid which fills the chambers and passages located downstream of it is identified by arrows 224, 226, 228, and 230. The pressure applied by the secondary fluid to a third diaphragm 231 opens the diaphragm valve provided by this diaphragm and an associated seat or cut-off 233, thereby allowing the secondary fluid to follow the route indicated at 224, 226, 228 and 230. Second diaphragm 220 contacts, as shown in Fig 24, an annular cut-off 223 so as to prevent the possibility of fluid discharge in the reverse direction via inlet 206.
Accordingly, mixing of the primary and second fluids occurs partly in annular passage 212 and is supplemented in mixing chamber 210 before the mixture reaches nozzle 20 and is spray-discharged as indicated at 232.
Fig 25 shows the return movement of thrust rod 216 at arrow 234, this movement producing a corresponding inflow of secondary fluid as indicated at arrows 236 and 238, in preparation for the next pumping stroke of the diaphragm assembly. This inflow is created because the diaphragm valve 231, 233 snaps shut, making the fluid flow route indicated at 236, 238 the only possibility for replacement of fluid. The return movement of thrust rod 216 continues the spray discharge from nozzle 20 as indicated at 232.
In this embodiment, as in the preceding embodiments, the directions of fluid flow required for operation of the
apparatus is produced by the arrangement of non-return valves discussed above and shown in the fluid flow circuit diagrams.
It is to be noted however that the first diaphragm 208 co-operates with an annular cut-off structure 240 associated with nozzle 20 so that, in its state of rest as shown in Fig 23 the diaphragm co-operates therewith to isolate nozzle 20 from mixing chamber 210.
A second annular cut off structure 246 co-operates with first diaphragm 208 near its outer periphery to complement the cut off function of structure 240.
Features of potential technical significance in relation to the embodiment of Figs 23 to 25 include the absence of sliding seals (due to the absence of pistons) , the continuous dispensing of secondary fluid during the pumping phase of cycle, and the use of an all-plastics polymer construction whereby the use of metallic springs is avoided. Thus, the diaphragms are of polymeric construction with the necessary inherent resilience. Additionally, the diaphragms, in their at-rest conditions, close off the supply of secondary fluid or concentrate (this being done by third diaphragm 242) and also close off the already mixed diluent and concentrate mixture (primary and secondary fluids) to nozzle 20 (this being done by first diaphragm 208 and structure 240) .
Due to the resilience of the diaphragms, the assembly has a pre-pressurisation feature whereby drip-free delivery from the nozzle can be achieved. This effect is enhanced by the reduced available surface area of first diaphragm 208 in its at-rest condition due to cut-off 240. A further feature of this embodiment is the provision of a swirl chamber 245 within nozzle 20 and produced within the structure of cut-off 240 and its end plate 247 by the provision of ports 249 which are out of alignment with the nozzle axis 251 so as to produce a swirl
effect and enhance mixing of the primary and secondary fluids.
In the embodiment of Figs 26, 27 and 28 a piston 250 has a return spring 252 and is slidable in a cylinder 254 having an inlet portion 256 for the primary fluid. The secondary fluid is supplied to the rodside chamber 258 of the assembly.
Piston 250 has a flexible annular sealing lip 260 which functions as a one-way admission valve for fluid between the opposite sides of the piston whereby, as the piston moves rearwards (or downwards as seen in Fig 26) , secondary fluid is admitted from chamber 258 into the headside or mixing chamber 262.
Piston 250 has an extended annular guide 264 at its rodside, and the guide cooperates with a complementary guide structure 266 mounted on cylinder 254. Guide structure 266 has a corresponding sealing lip 268 to allow inflow of the secondary fluid.
Piston 250 has a projecting cut-off head 270 with an annular sealing lip 272 to cooperate with the nozzle structure 274 to isolate the nozzle initially, under the action of spring 252. As in the embodiment of Figs 23 to 25, there is provided a swirl chamber 273 effective to produce a swirling action for enhanced mixing of the primary and secondary fluids due to non-alignment of inlet openings 275 with the nozzle axis 277.
Thus, in use, initial inflow of primary fluid to mixing chamber 262 produces pre-pressurisation. When the resilient loading of spring 252 is overcome, spraying commences through nozzle 20 and piston 250 moves rearwards, admitting further secondary fluid for admixture with the primary fluid.
At the end of the spraying stroke of the trigger,
pressure drops and spring 252 returns piston to the Fig 26 position.
Fig 27 shows piston 250 moving rearwards and secondary fluid entering chamber 262 at 276 while primary fluid enters at 278.
Fig 28 shows piston 250 returning under the action of spring 252 while spraying continues and secondary fluid passes lip 268 as shown at 280.
Features of technical significance in relation to the embodiment of Figs 26 to 28 include the non-return valve function of the flexible cup or lip-type seals 260 and 268 whereby a positive pumping action is achieved under spring return. Moreover, continuous dispensing of concentrate into mixing chamber 262 is provided during the pumping phase of the cycle as piston 250 moves rearwards. The large volume of mixing chamber 262 and the swirl effect produces by the secondary fluid entering it past seal 260 produce good mixing. Additionally, in the at-rest position of piston 250, it closes off the supply of both fluids to nozzle 20. Finally, the spring 252 and sealing lip 272 provide a pre-pressurization function whereby drip-free delivery can be achieved.
Turning now to the embodiment of Figs 29 and 30, this employs a venturi system for pumping the secondary fluid to the spray head for admixture with the primary fluid.
As shown in Fig 29, the piston and other pumps of the preceding embodiments are replaced by a venturi assembly 290 which draws the secondary fluid from its reservoir 16 via a pre-pressurisation-operated valve 292.
Venturi assembly 290 is driven by fluid from primary fluid pump 38 through a pre-pressurisation valve 294.
As shown in Fig 30, venturi assembly 290 comprises a profiled venturi jet 296 which is loaded by a spring 298 against an inlet port 300 so as to produce the pre- pressurisation valve effect.
Secondary fluid is delivered to assembly 290 via a fluid line 302 which can be aligned with an inlet port 304 in the venturi jet 296.
In use, secondary fluid or diluent supplied via fluid line 306 rises in pressure until valve member 308 on venturi jet 296 lifts from port 300, whereupon the venturi jet moves leftwards as seen in Fig 30, aligning inlet port 304 with fluid line 302 and admitting secondary fluid under the effect of the pressure reduction caused by the venturi effect of primary fluid flow through the jet 296.
Thus, a mixing of the primary and secondary fluids occurs in the venturi jet assembly and in the following chamber 310, whereupon the mixed fluid is ready for discharge through nozzle 20.
Technical features of significance in relation to the venturi system of Figs 29 and 30 include the pre- pressurisation feature which ensures that primary fluid pressure and flow are sufficient to enable the venturi to work immediately the valve opens. Additionally, the secondary fluid is drawn into the primary fluid stream by the venturi and thus is vacuum driven. The continuous delivery of secondary fluid in this way ensures good mixing with the primary fluid. Moreover, when the flow of primary fluid stops, the second fluid delivery is shut off by return movement of the venturi jet under the action of its return spring.
In the embodiment of Figs 31 to 34 there is provided an
elastomeric valve and pump assembly for the secondary fluid in place of the various pumping arrangements described in the preceding embodiments. The supply of primary fluid or diluent is provided as previously, by the primary fluid pump 38, and the delivery of mixed fluids from the assembly shown in Figs 31 to 34 is to nozzle 20, likewise as described previously. Therefore, in this embodiment there will be described only the details of the secondary fluid pump arrangement.
In the pump assembly 320 shown in Figs 31 and 32, primary fluid passes through the assembly in a primary fluid flow channel 322. Located below channel 322 is an elastomeric bellows-like pumping element 324 which is sealed at 326 and 327 to channel 322, at both of its ends. A fluid line 328 is connected to the supply of secondary fluid, and may merely dip into such supply.
A port 330 opens between channel 322 and the inner volume of pumping element 324.
Actuation of pumping element 324 is effected by main trigger 24 which is provided with a rearward shoulder 332 against which a bifurcated spring 334 acts, and likewise acts on a pressure plate 336 located at the under side of pumping element 324.
Figs 31 and 32 show the limit positions of trigger 24. In Fig 31 the pumping element 324 is in its maximum volume pre-discharge position. In Fig 32 the pumping element is shown in its more or less completely discharged condition. The arrows 338 and 340 illustrate the discharge of secondary fluid into channel 322 and the onward flow of the admixture thereby produced, respectively.
This embodiment permits the relative proportions of the primary and secondary fluids mixed to be determined by the
volume of the pumping element 324. In the preceding embodiments, the proportions are determined in various ways including, for example, the sizes of the inlet ports or jets admitting fluids to the mixing chambers, or related factors. It will therefore be appreciated that the relative volumes mixed can be changed by a simple redesign, or even by substitution of one jet or port for another.
Figs 31A and 31B together with Figs 32A and 32B and Figs 33 and 34 show the cross-sectional shapes of the elastomeric element arrangement and its disposition in relation to the primary fluid flow channel 322. It can be seen that the pumping element entirely surrounds the channel 322, and port 330 formed in channel 322 is generally of slit-form. Moreover, the pumping element has a lower thickened portion for co-operation with pressure plate 336, and the profile of the pumping element as it is compressed by pressure plate 336 is of significance in relation to its pumping action, Fig 32B showing it compressed from its uncompressed Fig 3IB condition. Figs 33 and 34 show an alternative section for the pumping element, in which it has a more rectangular shape and nevertheless compresses in a manner similar to that of Fig 32B to produce a relatively low volume within it at its fully discharged position shown in Fig 34.
The technical significance of the features of the embodiment of Figs 31 to 34 include the fact that the pumping and non-return valve functions of the assembly are both provided by the pumping element 324. The non-return valve function is identified at nip 342 in Fig 32. This nip simultaneously closes off the supply of secondary fluid before pumping commences. Also, the elastomeric pumping element provides energy storage during the pumping phase of the cycle so that fresh secondary fluid can be drawn into the pump when the bellows recuperate during the induction phase.
It is also noteworthy that the pumping element also provides a delivery valve for the secondary fluid, this being constituted by portion 344 of the pumping element, which closes off the port 330 as shown in Fig 31. During pumping, the internal pressure of secondary fluid lifts and opens the valve, but when the trigger 24 is released, the valve automatically closes as the pressure falls. This prevents the primary fluid contaminating the secondary fluid.
Additionally, this embodiment provides continuous delivery of secondary fluid into the primary fluid stream during pumping.
In the embodiment of Figs 35 to 39 there is provided, in place of the elastomeric pump of Figs 31 to 34, a peristaltic pump 350 operated by trigger 24, the trigger having, however, a modified structure at its upper and inner end, to accommodate the structure of the peristaltic pumping mechanism, notably the roller arm 352 thereof.
As in the previous embodiment, there is provided a primary fluid flow channel 354 which extends within the pod 78 towards nozzle 20. In Fig 35, arrow 356 indicates primary fluid flow and into this flow ir injected a supply of secondary fluid as indicated at 358 and the mixed fluids proceed towards the nozzle at 360.
The details of peristaltic pump 350 will now be described. The pump comprises a pump element 362 in the form of a flexible membrane attached to the outer surface 364 of pod 78.
Pump element 362 has an inlet opening 366 through which secondary fluid is delivered to it, and an outlet opening 368 through which the secondary fluid is delivered via an internally projecting injector nozzle 370 into the primary
fluid flow in duct 354.
Trigger 24 is pivotally mounted at 372 on a yoke 374 fixed to the main housing of apparatus 10.
In this embodiment, broadly speaking the mode of operation of the pump is similar to that of the preceding embodiment to the extent that the action of trigger 24 causes sealing-off of the supply of secondary fluid and progressive discharge of same by trigger angular movement causing a progressive reduction in the volume available for containing the secondary fluid within the space between the pumping element and the pod 78, whereby pressure is raised and the secondary fluid is discharged through injector nozzle 370.
The pumping action is effected by roller arm 352 which is pivoted to trigger 24 at 376 so as to be capable of an over centre movement between the positions shown in Figs 35, 37 and 39, and the position shown in Fig 38. The limit positions are defined by stops 378 and 380 which are engageable by a rounded end formation at one end of roller arm 352. At its other end it is provided with a rotary roller 382 for engagement with the pump element 362.
As shown in Fig 36, roller arm 352 is of generally of H- shaped form with roller 382 mounted for rotation between the side arms thereof, and the roller arm itself being pivotally connected by a pin 376 to a projecting end support arm 384 formed integrally with trigger 24.
Trigger 24 actuates its associates primary pump through a drive pin 386 and an associated connector 388, in a manner generally similar to that adopted in the previous embodiments.
Figs 35 to 39 illustrate the sequence of movements of trigger 24 and roller arm 352. Fig 39 shows the assembly in
its commencing position with roller arm 352 at one of its end limit positions, being its position for pumping purposes. Roller 382 is compressing pump element 362 against pod 78. Inlet opening 366 is thereby sealed off from the discharge nozzle. Outlet opening 368 remains able to communicate with injector nozzle 370. As trigger 24 moves anti-clockwise about pivot 372, roller 382 can progressively compress the trapped secondary fluid and cause it to be injected into primary fluid flow channel 354 for admixture to the primary fluid.
Fig 35 shows the trigger in its next onward movement from the Fig 39 position, and Fig 37 shows it approximately in its end limit position before roller arm 352 is caused to move over-centre as shown in Fig 38, by virtue of the end resistance provided by a stop 389 provided by a fixed adjacent structure in the trigger-mounting region. The geometry of the trigger/roller arm is such that the roller 384 does not pressurise the pump element 362 on the return stroke. At the end of the return stroke, the base of the roller arm strikes a second stop 391 spaced from stop 389, which moves the roller arm 352 over-centre in readiness for the next pumping stroke.
The lower surface 364 of the pod 78 is relieved slightly at the ends of the travel of roller 384 to ease the operation of the over-centre action.
Fig 37 shows associated with the trigger assembly seen in side elevation, a corresponding plan view of the relative disposition of parts with respect to the primary fluid flow channel 354, the pump 350, the injector 370 and the inlet opening 366.
The technical significance of the principal features of the embodiment of Figs 35 to 39 includes the following. Firstly, the over-centre action of the roller arm 352 creates a one-way pumping action for the primary fluid in the required
direction. The polymeric material chosen for the upper end portion of the trigger provides the necessary degree of resilience for the over-centre action of the roller arm, while the latter is also compliant to provide in its spring loading for the roller 382 itself. The stops 389 and 391 provided adjacent the trigger serve to move the roller in its over centre action in the region of the end of its reciprocating movement, this action being facilitated and provided in combination with the interaction of the roller arm with the relatively rigid periphery of the pod 78.
The pump element of the peristaltic pump is mainly a flexible membrane attached to the outside of the pod 78 enabling concentrate to be drawn in behind the actuating roller 382 during the delivery phase of the pumping cycle. This eliminates the need for suction and delivery valves. During pumping, the concentrate or secondary fluid is delivered continuously into the primary fluid stream, and when trigger 24 is released, roller 382 cuts off the secondary fluid supply from the nozzle, as shown in Fig 39.
Turning to the embodiments of Figs 40, 41, and 42, these differ from the preceding embodiments in that the secondary reservoirs and associated nozzles and pumps are provided in a different form so that a plurality of spray pods can be simultaneously mounted at the spray head for selective use in sequence, each spray pod having its own nozzle and being brought into operative relation with the remainder of the apparatus by simple manually-operable means. Thus, in these embodiments, instead of dismounting a pod from the spray head when use of the pod has been completed and it is to be replaced by another, manually operable means is actuated to bring the next pod into use, without the need for a dismounting operation.
In the embodiment of Fig 40, spray pods 400 each have a
nozzle 402 and are mounted for rotary motion about a lengthwise stem 404 for selective interchangeable use by rotation about the lengthwise action of stem 404. In this embodiment, it is the uppermost pod which is operative, as indicated by an arrow 406.
Primary fluid is delivered to the nozzles for admixture with the secondary fluid from the primary fluid reservoir 408 and via a duct provided in stem 404.
In this embodiment, the pods employ the same general principals of construction as described above in the preceding embodiments, but without the need for detachment of a pod when its use is completed. The pods are allowed to remain in position until exhausted. Connection of the pods to the delivery system for primary fluid may utilise a bayonet connector in a manner similar to that adopted in the preceding embodiments, with some modification to the requirement for relative turning movement between the pod and the main body as the final step in the connection process.
A rotary valve is provided within the spray head to be operated by the rotary selection movement about the axis of stem 404 to enable the selected one of the pods 400 to be connected to the primary fluid supply at any given time. The other pods are sealed off.
Further features of this embodiment provide that the pods may only be removed in their non-spray positions, whereby primary fluid may not be accidentally sprayed. Likewise, visual and tactile indication is provided by means of arrow 406 and correspondingly, located compliance and resistance in the turning motion of the assembly of pods, to identify the correct position for each. The pods 400 are removable in a radial direction with respect to the lengthwise axis of stem 404.
Otherwise, this embodiment is constructed generally as described previously, including the primary fluid pumping arrangements including trigger 410.
In the embodiment of Fig 41, the four spray pods 412 are disposed for selective motion about the lengthwise axis of an upwardly-extending stem 414, and each pod has its own nozzle 416 as previously. As in the preceding embodiment, the pods are inserted radially with respect to stem 414, or axially.
In the embodiment of Fig 42, the pods 418 have nozzles 420 and selection of the required pod is by means of a "piano key" push-select facility 422 provided on each pod.
In this embodiment, the pods 418 are arranged to be inserted either from above or by an inward swinging movement from the front of the assembly.
As in the preceding embodiments, visual and tactile indication is provided of the selected pod 418.
Turning now to the embodiment of Figs 43 and 43A, the drawings show details of a modified primary fluid reservoir for use in the preceding embodiments, but which is also applicable generally to trigger spray apparatus, whether employing two fluid reservoirs, or only one.
As shown in Figs 43 and 43A, primary fluid reservoir 430 is formed with an integral dip tube portion 432 located on the rearside of the reservoir, that is to say on the side remote from the trigger, and thus rearwards with respect to the direction of spraying. In a modification (not shown) the integral dip tube portion is located on the forward side of the reservoir, having regard to the direction of spraying.
Dip tube portion 432 is defined by an integrally moulded
tube 434, formed integrally with the remainder of reservoir 430, and joined thereto along the majority of its length by a neck portion 436 in which the two walls 438 and 440 are joined together.
Reservoir cap 442 is adapted to engage the reservoir 430 in sealing fashion and comprises a vent tube portion 444 and a delivery tube portion 446 for application of suction from the trigger pump.
In use, reservoir 430 operates substantially as the conventional dip tube reservoirs do, but enjoys the technical features of correct positioning of the inlet end of the tube 434 in relation to the remainder of the reservoir at all times, and the avoidance of a separate dip tube attached to the pumping apparatus avoids the problems of dripping when fitting a new reservoir. Moreover, there is no need to match the length of the dip tube to the reservoir when the dip tube is formed integrally therewith, or fixed therein.
Amongst other modifications which could be made in the above embodiments and which lie within the broadly envisaged aspects of the invention are the following. Firstly, the invention envisages the use of quickly interchangeable reservoirs of secondary fluid, which can be connected to the apparatus by a quick-attached system such as a bayonet coupling. Usually, for convenience, the secondary reservoirs will be at a location in the region of the trigger and/or spray nozzle, but not necessarily so. Thus, in some instances it may be possible or convenient to deliver primary fluid as a pumping medium to a secondary fluid pump at some location other than strictly adjacent the nozzle. Thus, those skilled in the art will be able to envisage modifications to the disclosed system of plug-in pods or reservoirs, where a particular application suggests or requires it.
Likewise in those circumstances where the secondary fluid is not of a nature to present a safety hazard, then those features described in the embodiments for ensuring avoidance of dispensing of neat secondary fluid, may not be required.
Considerable variation in the relative volumes of the primary and secondary reservoirs may be adopted according to particularly conditions of usage. The volume of secondary fluid dispensed per stroke of the dispensing trigger will depend upon a considerable number of design factors which can be relatively easily varied.
The integrally moulded dip tube may be applied to an extremely wide range of hand-held trigger-operated spray devices.