NZ200968A - Dispensing measured doses of drench liquid to remote drench gun;lines to and from pump include pinch valves - Google Patents

Description

200968 Patents Form No. 5 PATENTS ACT 1953 COMPLETE SPECIFICATION After Provisional No. 200968 Dated: 15 June 1982 "IMPROVEMENTS IN AND RELATING TO DISPENSING OF LIQUIDS AND LIQUIFIED MATERIALS" We, ENGINEERING DYNAMICS LIMITED, of 12 Railway Avenue, Lower Hutt, New Zealand, a company organised and existing under the laws of New Zealand, hereby declare declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement:- fS 200368 This invention relates to the dispensing of liquid materials, substances and compounds, including dispersions and solids in suspension (all hereinafter embraced by the term "liquid(s), liquid and liquidised 5 materials"), and in particular relates to the dispensing of such materials in metered or prescribed amounts such as may be required in the dispensing of measured amounts or doses of medicinal liquids and liquidised materials to animals by way of a drench gun. It is to be apprec-1 0 iated however that the invention is not necessarily confined to such veterinary applications, and may have other applications in the dispensing of liquid and liquidised materials.

In order to dispense liquid and liquidised 15 materials in measured doses, it is common to provide a hand or power operated pump system which utilises or incorporates non-return valve mechanisms such as ball valve or poppet valve mechanisms and such valve mechanisms are fully effective provided that the material being 20 pumped is a free flowing liquid clear of grit or hard lumps or even soft and partially undissolved lumps of materials, such as may commonly occur for example in animal drenches made up from simple powder materials or powder materials which are mixed with liquids to be held 25 in temporary suspension to facilitate drenching or ,4 dosing. Accordingly, one principal object of the invention is to provide pumping and dispensing apparatus for liquid and liquidised materials 20MAY1986# 200968 1 0 1 5 20 25 and including valving means capable of effectively operating in the pumping and dispensing of materials containing grit, lumps or partially undissolved powder materials, as well as having general purpose applications . advantages of the invention will become apparent from the ensuing description. therefor, there is provided a means for dispensing liquid and/or liquidised materials in prescribed amounts comprising a pump unit housing a reciprocally movable diaphragm and/or piston unit defining a wall of a pumping chamber of the pumping unit and actuable by an intermittently applied force, an inlet to said chamber arranged for connection via first valving means to a supply source of the material to be dispensed and an outlet from the chamber arranged for connection via second valving means to a dispensing nozzle device; said first and second valving means being synchronized for alternate opening and closing in conjunction with movement of the diaphragm and/or piston unit for induction to and explusion from the pump chamber of the material, and said first and second valving means including resilient flexible tube parts which are alternately compressible to prevent the flow of the material Other and more particular objects and According to one aspect of the invention / 200968 therethrough.

In another aspect of the invention, there is provided the means according to the preceding paragraph and wherein said flexible tube parts of 5 the first and second valve means are alternately compressible by a common reciprocally movable member.

In a further aspect of the invention there is provided a means for dispensing liquid and/or liquidised material in prescribed amounts comprising 10 a diaphragm pump unit, diaphragm main valving means for effecting alternate compression and closing of the first and second flexible tube valving means controlling flow of the material to and from the pump, and a diaphragm actuated control means 15 for effecting synchronized operation of the diaphragm pump and diaphragm main valving means.

In a still further aspect of the invention, a supply tank or reservoir for the supply of the liquid and/or liquidisedmaterial includes a separate 20 compartment housing at least one baffle or deflector plate and having an inlet for air under pressure, there being a passage providing communication between the inner base parts of the tank and compartment for the passage of material 25 from the compartment to the tank for agitation of the material on application of air pressure to the compartment. '20MAYI986 IN Z. rr v.. .y I ^ 200963 As previously indicated, the invention is particularly applicable to drenching operations, and some preferred aspects of the invention will now be described with reference to such an 5 application and by way of example with reference to the accompanying drawings, in which FIGURE 1: is a schematic drawing illustrating one first arrangement of drench application apparatus; FIGUEE 2: is a cross-sectional view of one form of the main valving means, shown actuated in closing one flexible tube part; FIGUEE 3; is a view similar to figure 2 and showing the valving means in the mid or 15 neutral position and closing both tube parts; FIGURE 4: is a cross-sectional view of one form of pump in accordance with the invention; With modifications in figures 4A and 4B; FIGURE 5; is a sectional view more 20 particularly illustrating one form of drench gun and one form of control valve means for controlling operation of the main valving means and pump; FIGURE 5A: is a fragmentary perspective 25 view illustrating an alternative nozzle end part for the dredge gun of figure 5; v. ? r *v \ 2 0 MAY 1946 £ 200968 FIGURE 6: is a cross-section view illustrating one preferred form of supply tank incorporating an agitating means, FIGURE 7: is an agitator control means for intermittent operation of the agitator supply tank exampled in figure 6.

FIGURE 8: is a diagrammatic illustration of an alternative drench installation in accordance with this invention applied by way of example, to a twin herringbone milking shed; FIGURE 9; is a side view of an alternative preferred form of drench gun; FIGURES 10 and 11; are diagrammatic sectional views respectively illustrating an alternative arrangement of pump and valve unit in accordance with the invention; FIGURE 12: is a fragmentary plan view of the encircled portion 'X' of figure 11; FIGURE 13; is a diagrammatic view of another agitator pump arrangement in accordance with a modification of the invention; FIGURE 14; is a view illustrating a cabinet incorporating a liquid reservoir and housing parts of the drench system in accordance with a preferred arrangement of the invention, and FIGURE 15: is a diagrammatic illustration of a still further modification to and application of the invention. / #» 200968 Referring firstly to figure 1 of the drawings, a supply tank or reservoir S is arranged to contain a supply of the liquid or liquidised material required to be dispensed or applicated, 5 and a main material pipeline Ll extends from the supply tank S to a diaphragm pump unit P by way of a pump valve PV, and the material passed to the pump P is pumped therefrom by way of a secondary material pipeline L2 to the drench or 10 dispensing gun G, the line L2 passing to and from the pump main valving means.

At least the portions of the pipelines Ll and L2 within the pump main valving means are flexible tube parts which are alternately compres-15 sible and the actuation of the pump main valving means PV is synchronized with operation of the pump P and controlled by a control valving means CV so that line Ll is open and line L2 closed during the suction movement of the pump P, and 20 line L2 is opened whilst line Ll is closed on the pumping or expulsion movement of the pump P. Actuation 20MAYI986; I 200968 of the control valve CV is arranged to be effected by an operator of the drenching gun G, and in one preferred means for effecting operation of the apparatus,and as is convenient, in farm operations 5 where there is generally a source of air pressure supply, air under pressure from a main source M is directed to the control valve CV from which two lines extend to or are placed in communication with the pump P and pump main valving means PV 10 which preferably are or incorporate diaphragm operating mechanisms. The control valve CV preferably also incorporates a diaphragm which is coupled by air lines to the main air supply line and the gun with an adjustable flow regulator valve Rl 15 controlling and substantially reducing the flow of air under pressure to the control valve CV and gun G, the gun operator being able to control the extent of air pressure build-up in the control valve diaphragm unit for operation 20 thereof as required.

Where, as is commonly the case, the material to be dispensed is a powder/liquid mix in which the powder material is likely to be only in temporary suspension, unless the mix is agitated j 25 or stirred frequently the temporarily suspended material will settle out, at least in part. Accordingly, it is desirable to provide for continuous -8- !v 20 MAY 1986& «* 200968 or intermittent agitation or stirring of the material within the supply tank S during operation and dispensing of such material, and the mains air pressure M may be conveniently utilised also 5 for effecting the required agitation. Continuous agitation will in most cases not be necessary and therefore intermittently controlled agitation can be provided for and figure 1 illustrates at A an agitator control means for intermittently 10 allowing air under pressure to pass to the supply tank S. Full continuous mains air pressure will not be required for such operation and a further air flow regulator R2 can be provided to control the air flow to the agitator control means A. 15 Referring now also to figures 2 and 3 of the drawings, the pump main valving means PV may comprise a diaphragm unit including a rigid two-part housing 1 with a flexible diaphragm 2 located and secured between mating peripheral flange parts 20 la thereof and thus defining two separate compartments 3 and 4 through which flexible and resilient tube parts Ll' and L2' of the material supply and dispensing lines Ll and L2 can respectively pass. The tube parts Ll' and L21 within the housing 25 compartments 3, 4, are arranged to be alternately 2O0J6% figure 2 tube part Ll* is shown compressed and L21 is shown expanded and open). It is desirable that there is no overlap of operation whereby both tube parts Ll' and L2• are open or partially open at the 5 same time and thus the arrangement of the pump main valving unit PV is such that there is an intermediate or neutral position with the diaphragm pressures balanced and both tube parts Ll' and L21 closed (as illustrated in figure 3) before part 10 Ll' is opened from the closed position illustrated in figure 2.

Compression of the respective tube parts Ll', L2', is arranged to be effected by rigid compression members 5 secured to the diaphragm 15 medial portion, the respective tube parts Ll' , L2 ', being located between such rigid compression members 5 and appropriate fixed bearing parts lb of the housing 1; and in the one first arrangement illustrated in figures 2 and 3 20 of the drawings, the compression members are flat plate members 5 each provided with a pair of spaced apertures through which a pair of parallel guide rods 6 extending perpendicular from rigid support parts 2b of the diaphragm are slidably 25 located; the compression members 5 being normall^^^-^ ^ biassed away from the diaphragm 2 by means of (f f < compression springs 7 located about the guide p <o ... y ^'£.7 V F 200368 rods 6 so that a controlled and resilient pressure can be brought to bear on each of the tube parts Ll' and L21 without risk of damage to such tube parts Ll', L21. Appropriate end stops or collar 5 portions 6a can be provided on the guide rods 6 to limit the amount of travel of the compression members 5 under the spring bias and also to limit the extent of movement of the diaphragm 2 and thus avoid over compressing the tube parts Ll' and L2' 10 in a manner likely to cause damage thereto.

The employment of a natural or synthetic rubber for the material supply lines Ll and L2 can be further utilised to advantage with this kind of pump main valving means in that the lines 15 need not in fact be broken or terminated at either side of the valving means PV but can be continuous and, after a period of use with the valving means in one location relative to the pipelines Ll and L2, the pipelines Ll and L2 may be adjusted a little 20 lengthwise through the housing 1 of the main valving means PV to provide fresh points of compression and thus avoid premature fatigue and failure of the pipelines Ll and L2 at the main valving means PV with the frequent compression and 25 expansion. The pipelines Ll and L2 may locate at a close self-sealing fit within appropriately dimensioned apertures in the respective housing I 200368 parts 1. The respective housing parts 1 are provided with appropriate air bleed apertures 8 and air pressure inlets 9 for the alternate supply of air under pressure to each compartment 3, 4.

In a modification of the invention not illustrated, instead of the single diaphragm unit illustrated at figures 2 and 3, a pair of co-operating diaphragm units can be located in juxtaposition with their diaphragms coupled by a 10 connecting rod for simultaneous operation, and the pipelines Ll and L2' located one through each diaphragm unit on the outer part thereof remote from the connecting rod for compression between the housing and a bearing or compression plate on 15 each diaphragm.

The pump unit P may take various forms and preferably also includes a diaphragm for effecting the pumping operation, and one form of the invention is shown now in figure 4 of the drawings. 20 In this arrangement the diaphragm unit includes two housing parts 10 (which may be similar in size and construction to the diaphragm housing parts 1 for the main valving means PV, for economy in manufacture) with a flexible resilient diaphragm 25 member 11 secured at its periphery between peripheral flange portions 10a of the housing parts 10, and dividing the housing into two chambers 12 and 13 I 200968 one of which is the pumping chamber for the liquid material 14 and has the inlet 12a from material line Ll and the outlet 12b for.material line L2. It is envisaged that air pressure can be supplied 5 directly to the other compartment 13 for effecting movement of the diaphragm 11 in the pumping operation, and for readily pumped liquids this arrangement may suffice. However for more difficult liquids or liquidised materials such as may apply to animal 10 drenches, a more positive operation of the diaphragm 11 may be necessary and it may be further desirable to provide a pressure compensating fluid or liquid on the opposite side of the diaphragm 11 so that the diaphragm 11 is not strained whilst being flexed 15 during pumping operations. In the one form of the invention illustrated by way of example in figure 4, a pneumatic cylinder 15 reciprocally housing a double acting piston unit 16 is mounted on the side of the housing 10 remote from the material pumping 20 side and said opposite chamber part 13 and adjacent end part 15a of the cylinder 15 are filled with a compensating liquid such as oil 17. The double acting piston unit 16 comprises a pair of spaced piston members 16a and 16b coupled by a connecting 25 rod 16c slidably located in an aperture in a fixed divider 18 dividing the bore of the cylinder 15 into two inner compartments 19a and 19b between I ^ 800968 between the two piston members 16a, 16b. The piston members 16a, 16b are provided with appropriate peripheral seals and a small amount of oil 17a can be also provided in the portion of the chamber 19b 5 between the fixed divider 18 and the piston member 16b nearest the diaphragm 11 to prevent air leakage; and the chamber 19a on the outer or opposite side of the divider member 18 is provided with two air supply ports 20 providing communication to 10 such chamber 19a at either side of the outer piston member 16a for effecting reciprocation of the piston member 16a and piston unit 16 as a whole for exerting and relieving pressure on the oil 17 and thus the diaphragm 11 in effecting the pumping 15 operations. The length of stroke of the piston unit 16 can be made adjustable such as by a screw-threaded adjusting member 21 located at the outer end wall 15b of the pneumatic cylinder 15 and providing an abutment for the outer piston member 16a. 20 In some instances and particularly where a lengthy material outlet pipe L2 is in use, when the w„.y pump diaphragm 11 reaches the end of its travel on the pumping stroke (downward) it will stop pumping but the momentum of the long column of ;y 25 liquid material 14 (which is being discharged from the pump P) tends to continue its motion down the discharge line L2. If conventional check valves 20096S are installed on the pump unit, then the valve on the suction line Ll could open whilst the column of liquid material in line L2 came to rest. This would mean fluid could be induced into the pump chamber 12 while the diaphragm 11 was not moving and thus the quantity of liquid material 14 dispensed at the drench gun G could exceed the normal displaced volume of the pump chamber 12. This over induction of material can be' prevented by use of a "brake", "stop" or "deceleration" valve built into the pump unit P. One form of "brake" or "stop" valve is illustrated in figure 4A of the drawings and it should be noted that this arrangement has application only with pumps which do not have conventional check valves. The diaphragm 11 has a valve plate 11a the periphery of which is arranged to seat on a valve seat lib of the housing 10 above the inlet 12a and outlet 12b so that liquid being discharged from 12b (L2) cannot induce cavitation in the oil or other liquid 17 above the diaphragm 11, and the momentum of the liquid column in line L2 is absorbed by the resilient nature of the material of which the line is formed. The mating portions of the valve plate 11a and/or valve seat lib, at least, can be of a resilient material.

In an alternative arrangement and as illustrated in figure 4B, a deceleration valve is 2009SS provided and which can be used for pumps with "traditional" check valves. This arrangement includes a tapered needle 11c depending from diaphragm plate 11a to align with or locate in the outlet port 12b which is co-axial with the housing, and it will be noted that as the diaphragm 11 descends the needle 11c of varying cross-section enters the orifice of outlet 12b. Thus the orifice reduces in size as the diaphragm 11 descends and at the end of the diaphragm stroke the orifice is completely occluded. Thus liquid material 14 cannot be further sucked into the pump by the continuing motion of the discharged column of liquid material 13 in line L2. The varying cross-section of the needle 11c enables the discharge rate of liquid material in line L2 to be more gently or gradually brought to rest.

The invention further includes a first novel drench gun G of very simple construction and operation, and preferably with no moving parts. This form of drench gun G in accordance with the invention is illustrated by way of example in figure 5 of the drawings, and with reference to figure 5A illustrating an alternative outlet nozzle part for the gun. The gun G may include a solid hand piece 21 manufactured from such as an aluminium alloy or a plastics material and having an open conduit 23 200368 extending therethrough with a lower end portion 23a projecting through the butt of the hand piece 22 for connection to the flexible pipeline L2, and an upper forwardly extending outlet end part 23b having an outlet nozzle end piece 24. The outlet end part 2 3b can be rigid and unflexible, or may be articulated or be a reinforced flexible tube part e.g. by having a spirally wound flexible metal sheath, enabling angular adjustment of the outlet part 23b. The outlet part 23b of the conduit 23 is preferably provided with a rubber or resilient plastics nozzle end piece 24 to avoid damage to an animal on insertion of the nozzle end part 24 for drenching operations, and preferably the nozzle end part 24 is arranged to be normally closed to prevent contamination of the medication or drench material by air or dust and also to prevent drip of the medication or drench from the nozzle end part 24 after a drench has been administered. The arrangement illustrated in figures 5 and 5A provides a simple and effective self-closing nozzle end part 2 4 and comprises a tubular end piece normally closed at the outer end, which may be of rounded or conical formation, and such normally closed end part is provided with a plurality of longitudinal slits 24a intersecting at the outmost free end so that when the drench material is applied under pressure through 200968 the outlet conduit 23 the end portions 24b of the nozzle end part between the slits 24a open out in the form of petals to permit egress of the drench material; and on cessation of pumping of the 5 material the petal end portions 24b will close due to the inherent resilience of the rubber or like material. A nozzle end part 24 may be easily fitted to and replaceable on the outlet end part 23b of the conduit 23 and may be retained in position by 10 providing the outlet end part 23b of the conduit 23 with an annular rib which is locatable in a complementary inner annular recess provided in the wall of the nozzle end part 24.

As previously mentioned with reference to 15 figure 1 of the drawings, the gun G is coupled by an air line 25 to one side of a diaphragm unit, 26 (which may be of similar form to the previous diaphragm units) of the control valve mechanism CV and to the main air supply line M by way of an adjustable 20 air flow regulator valve Rl. Air under pressure is thus continually slowly bled to the air line 25 j between the gun G and the control valve diaphragm unit 26 and whilst drench is not being administered the air may be permitted to leak or bleed from an ^ 25 orifice 27 in or at the gun hand piece 22 so that an operator, when requiring to administer a drench, may simply close the orifice 27 with a thumb or finger to I J2Q0968 y <?0 Y- Yr "**1986:1 ■ I allow air pressure to build up within the air line connecting with the control valve diaphragm unit 26 until the pressure build up within the diaphragm unit 26 is sufficient to deflect the diaphragm 26a and effect actuation of the connected control valve 2 8 to direct air to the appropriate sides of the pump diaphragm unit and pump main valve diaphragm unit.

Once the control valve 28 is so actuated it is not necessary to maintain the air bleed orifice 27 closed as the seguence of operations follows automatically with operation of the pump P and opening of the outlet line tube part L21 to allow passage of pumped drench material 14 therethrough to the gun G and automatic return of the diaphragm member 11 and 2 of the pump P and pump main valve unit PV closing off the outlet line L2 and enabling the second chamber 12 of the pump unit P to refill with drench material 14 ready for the next operation.

As an alternative to closure of the air bleed aperture 2 7 on the gun G by means of an operator's th-urnb or finger, a mechanical or electrical closure device can be provided and operable by a suitably positioned trigger or button; or in a further alternative arrangement, a mechanically or electrically operated stop valve may be provided in the air line connection 25a to the main air supply M to normally prevent the air flowing into the line connecting the f 200968 gun G and control valve diaphragm 26 so that there is no escape of air whilst the drench gun G is not in operation; and any suitable electrical or mechanical trigger means can be employed for effecting opening of 5 the stop valve to allow the passage of air to the control valve diaphragm unit 26.

Referring now to figures 6 and 7 of the drawings, the main supply tank S is preferably provided with an inclined base 29 so that any solids settling 10 out in the drench material 14 will normally fall to the lowest end or side of the supply tank S. The lowest or deepest end part of the supply tank S can be provided with a separate compartment 30 by providing a dividing wall 31, preferably inclined, extending 15 between opposite walls of the tank S and terminating short of the inclined base 29 so as to provide a communicating passage 32 between the compartment 30 and main area of the tank S. The lower end part of the dividing wall 31 may be turned inwardly into the 20 compartment and towards the respective end or side wall to terminate short thereof and form a first J baffle 33 running generally parallel with and in spaced relationship from the inclined base 29 so that there is an elongate passage 32 extending the full width ) 25 of the supply tank S and compartment 30 at the inclined base 29. A plurality of further baffle members 34 may be disposed in spaced and staggered relationship above 200963 the lowermost baffle 33 in the compartment 30 e.g. secured to and extending inwardly alternately from the inclined inner dividing wall 31 and the respective outer wall part 35 of the supply tank S, to provide a 5 tortuous communicating path between the said passage 32 and the upper part of the compartment 30. Air under pressure is arranged to be directed by way of a suitable conduit 36 to an inlet 36a in the upper part of the compartment 30, and preferably in an 10 intermittent manner so that the intermittently applied air pressure forces the liquid or liquidised material 14 in the compartment 30 to travel through the tortuous path and through the communicating passage 32 up along the inner side of the inclined base 29 of the 15 main supply tank S, to carry any settled-out material 14 upwardly and be deflected again on reaching the opposite side or end wall 35a of the supply tank S so that agitating currents (indicated by arrows 37) are set up within the drench material 14 in the main 20 part of the supply tank S. The main outlet 38 from the supply tank S for connection to the main supply line Ll is preferably in the inclined base 29 and towards the lower end thereof near the compartment 30, and an inner filter or strainer 39 is located 25 thereover; and the apertures of which strainer 39 are cleared by the jetting movement of the drench material 14 passing from the compartment 30 and agitated within 86 -21- 200968 the main supply tank S.

When air supply to the compartment 30 is stopped and exhausted, the liquid drench material 14 in the main part of the supply tank S may then refill the compartment 30 ready for the next agitating operation.

The intermittent supply of air under pressure to the drench material supply tank S can be provided by way of an agitator time delay valve unit A such as that illustrated particularly in figure 7 of the drawings, and including a cylinder 4 0 having a stepped bore 41, 41a, and reciprocally housing a complementary stepped piston 42. Air under mains pressure is directed by way of an air line 43 to the outer end of the smaller bore 41a, and air under reduced pressure e.g. reduced by way of a regulating valve R2 is fed to a reservoir 44 and from the reservoir 44 to the outer end of the larger bore 41 of the valve unit. The air line 36 to the compartment 30 of the main supply tank S is also coupled to the outer end wall 40a closing the larger bore 41 and a separate air bleed port 45 is provided at such outer end wall 40a. A further air vent 46 is provided in the wall of the cylinder 40 communicating with the inner part of larger bore 41 on the inner side of the larger portion 4 2a of the piston 4 2, and the arrangement thus provides that air under pressure is bled slowly into the reservoir 44 via the regulator R2 until the pressure within the reservoir 44 has risen to a point where the force exerted by the air pressure on the outer side of the larger part 42a of the stepped piston 42 exceeds the force applied by the main air pressure supply to the opposite outer end of the smaller part 42b of the stepped piston 42. At this point the piston is moved from the position indicated in full in figure 7 towards the opposite end part having the smaller bore 41a. Prior to this movement the entry port 47 from the reservoir 44 is arranged to be sealed from the exit port 36b to the tank air line 36 and the exhaust or air bleed port 45, and such sealing can be effected by locating the entry port 4 7 medially of the outer end wall 40a of the cylinder 40 and providing an annular resilient seal 4 8 about such entry port 4 7 and providing a seal between the end wall 40a and the outer face of the larger part 42a of the piston 42. Such seal 48 can for example be located in an annular recess 48a provided in the piston face (as shown), or alternatively in an annular recess provided in the end wall. Thus, on movement of the piston 42 towards the smaller bore end of the unit under air pressure from the reservoir 44, this static seal is broken and the full reservoir pressure is applied to the entire face of the larger end 42a of the piston 42 and can discharge the stored 20036S air from the reservoir 44 through both the exhaust bleed port 45 and through the outlet port 36b and air line 36 to the agitator baffle compartment 30 of the supply tank S. After a while, escape of air through the exhaust or bleed port 45 will permit the reservoir pressure to fall to a point where the force on the larger end 42a of the piston 42 will be overcome by the main air pressure applied to the smaller end 42b of the piston 42, and the piston 42 will return to its original position at the outer end 40a of the larger bore closing the static seal 48 between the inlet port 4 7 and the exhaust bleed and outlet ports 45, 36b, and air pressure will again begin to build up in the reservoir 44 ready for the next operation. The construction of the cylinder 40 and outer end wall 40a at the larger end of the bore 41 provides a communicating annular passage or chamber 49 between the exhaust bleed port 45 and the outlet port 36b so that when the valve is closed i.e. with the piston 4 2 at the outer end of the larger bore and sealed on the static seal 48, air in the agitator compartment 30 of the supply tank S is able to exhaust through the exhaust bleed port 45 to enable return of the liquid drench material 14 into the agitator compartment 30. The time delay period for operation of the agitator control unit A may be affected by the size of the reservoir 44 and by 20096$ varying the rate at which the reservoir 44 charges via the flow regulator R2.

Some further aspects and modifications or variations of the invention will now be further 5 described by way of example with reference to the figures 8 to 14 of the accompanying drawings.

Referring firstly to figure 8 of the drawings, a drench installation in accordance with the invention may be permanently set up in relation to a milking 10 shed such as the illustrated twin herring-bone milking shed 50 with a cabinet 51 such as that illustrated in figure 14 permanently mounted at a convenient location e.g. outside the milking area, such cabinet 51 housing a large dosing liquid reservoir 52 e.g. a 15 50 to 60 litre plastics holding tank which may contain sufficient for say 400 to 50 0 doses of drench or several days supply. The cabinet 51 may further house three diaphragm units in accordance with the invention and comprising an agitator pump unit 53 such as that illus-20 trated in figure 13, a valve unit 54 and main pump 55 such as those illustrated in figures 10, 11 and 12 and may also house a pressure surge chamber unit 56. Compressed air is provided for the installation from any readily available source or by way of an independant 25 small compressor mounted 57 in close proximity to the cabinet 51.

A dosing head 58 housing two similar diaphragm units 54' and 55', similar to the first valve and pump units 54 and 55, can be fixedly or movably mounted within 2009Sg the shed 50 and coupled by way of conduits 59,59" to the main recirculating pump 55 in the cabinet 51; and at least one but preferably at least two drench guns or more hand pieces 60, such as those illustrated in 5 figure 9 of the drawings,being coupled to the dosing head unit 58 by way of long flexible discharge lines 61. The discharge lines 61 can be a continuation of or coupled to the supply conduit 5 9 and the drench guns 60 could be coupled directly to and operated from 10 the first valve and pump units 54 and 55 when in close proximity in a similar manner to the arrangement of figure 1, but with the usually required long supply conduits 59 for installations of this nature and having regard to the heavy or thicker kinds of liquids to be 15 pumped, the dosing head 5 8 with the additional valve and pump unit 54' and 55' improves the liquid recirculation, pumping and drench dispensing operations. Figure 8 illustrates the employment of two drench guns or hand pieces 60, but it will be appreciated that a 20 single gun or hand piece 60 can be employed for a small shed or that additional drench guns or hand pieces 60 may extend from the same dosing head units 58 or from a further similar dosing head unit 58 coupled in series thereto.

With reference to figure 9 of the drawings, an alternative to the air controlled gun G may be a drench gun 60 comprising a simple hand piece or body part 62 through which an end portion 61a of a resilient flexible hose 61 jf- p P*T * .v /? °\ ' 2°May, - extends, (such end portion 61a may be an integral part of o\\ ^ - **9 200968 the main flexible connecting conduit 61 for the system or may be connected or connectable thereto by way of a rigid connector piece 61b anchored in the rear or butt part 62a of the gun, the forward or outer end portion of the part of the hose 61a within the gun 60 being anchored at the forward end part 62b of the gun 60 and connected to a rigid or semi-rigid drench gun nozzle end piece 63. The drench gun 60 has a trigger lever member 64 mounted by a transverse pivotal connection 65 to the body part 62 so as to be pivotally moveable towards and away from a hand grip portion 62c of the body part 62 and being normally biased away from such hand grip portion 62c by a biassing spring 66, the trigger lever member 64 having a transverse bar 67 extending below the hose end portion 61a to normally compress and close off the hose end portion 61a under the spring bias against the upper side 62d of the drench gun body part 62, but being releasable to allow passage of the drench liquid or fluid material to and out from the outlet end 63a of the nozzle piece 63 on am operator squeezing the trigger lever member 64 toward the hand grip portion 62c. The biassing spring 66 is preferably located at an inclination as indicated in figure 2 and may extend from a lower part of the butt or hand grip portion 62c directly to the transverse bar 67, the pivotal connection 65 for the trigger lever member 64 having its axis parallel with the transverse bar 67 and its relative location with the transverse bar 67 providing an "over-centre action" so that the biassing spring 66 is able to exert its maximum compressive force on the transverse bar 67 and hose end portion 61a to pinch H- 2°HAYi to S ^ / V S 2Q096S the hose end portion 61a closed (as indicated in broken outline in figure 9); but a minimum pressure is required to be placed by an operator on the trigger lever member 64 to overcome the compressive force and hold the drench gun 60 in the "open" position to allow the dispensing of the liquid drench therefrom.

Referring now to figures 10,11 and 12 the drenching apparatus or installation includes a first air valve 68 to which compressed air is directed from compressor 57 or another supply source, and which valve 68 includes a biassing spring 6 8a which normally sets the valve so that compressed air can pass to port "g" of the valve 6 8 and port "e" to one side of diaphragm valve unit 54 urging its diaphragm piston 69 downwardly to compress and close off the confined part 59a of compressible hose 59 drawing liquid drench from tank 52, and at the same time open the main discharge / valve hose 59. This same air is also directed to port "d" of pump 55 and also urges a piston 70 of the pump 55 (the pistons 69 and 70 being each coupled to a diaphragm 69a and 70a between the respective upper and lower halves of the valve and pump assemblies 54, 55) downwardly to displace liquid from the lower chamber "h" of the pump assembly 55 (air in the upper pump chamber "j" being also applied to the lower end part of a piston 71a in a second pneumatic valve 71 coupled to and co-operable with the pump 55, holding the piston 71a in a raised position).

As the pump piston 70 reaches the end of its stroke lobe C of pneumatic valve piston 71a is contacted and causes the second pneumatic valve 71 f * ' O A r ■?" O < 500968 to change over; the signal now issues from port "a" of the second pneumatic valve 71 and causes the first pneumatic valve 68 to change states. The same signal also directs air to port "f" of the valve unit 54 and the opposite or lower side of diaphragm 69a to close the pump discharge hose confined part 59a' in the upper part of valve 54 and open the pump delivery hose part 59a in the lower part of valve 54. Port "g" is no longer coupled to the air supply and air trapped in chambers "j" :and "1" of the pump and valve units 55 and 54 are now exhausted. Preferably the exhausted air under pressure is directed to escape into the reservoir or tank 52 of liquid so as to agitate such liquid and prevent settling out of solids in suspension. Since there is now no opposition to a biassing spring 72 of the pump unit 55, the pump unit 55 induces a fresh charge of liquid into its lower chamber through delivery hose part 59a. When the pump piston 70 reaches the upper end of its stroke, it actuates the second pneumatic valve 71 by striking lobe "b" and the valve 71 changes state to allow the first pneumatic valve 6 8 to restart the cycle.

As mentioned previously the drench gun or guns 60 could be supplied directly by pump unit 55, but for long line operations and efficient pumping and dispensing of the drench the additional dosing head 58 is provided with a second diaphragm valve unit 54' identical to unit 54 being coupled to the discharge Qjq ,nj| side of pump unit 55, and a second pump unit 55' coupled to the valve unit 54, gun lines 61 and 200968 1 o j recirculating line 59' to the tank 52; pump unit 55' being identical to pump unit 5 5 except that the piston return spring 72 is omitted as the lower chamber "h" of unit 55' is self charging with the drench liquid.

As previously mentioned, for the kinds of drench liquids and solutions commonly utilised agitation is desirable to prevent settling out. Thus, as an alternative to the earlier described agitation system in addition to the exhaust air agitation referred to, and referring now to figure 13 of the drawings, the apparatus or installation may include an agitator pump which again may comprise a simple diaphragm pump unit 53 actuable by the intermittently exhausted air under pressure so that the pulse of air may be 1 ^ applied to port "A" to force the piston diaphragm assembly 73 upwardly so that liquid in the upper chamber "E", which is coupled by a conduit 74 to the reservoir, is forced out of the upper discharge port "B" and conduit 74 to create a jetting effect 20 in the lower part of the reservoir or tank 52 and which serves to intermittently agitate the drenching mixture. When the air pulse is spent, air remaining in the lower chamber "C" of the agitator pump unit 53 is displaced to atmosphere by the piston assembly 7 3 returning to the 25 lower position under pressure of a biassing spring 75 in the upper chamber "E". A small 'breather hole "D" is provided in a wall of the lower chamber "C" to enable air escape on -return of the piston diaphragm assembly. At the /V \same time the returning piston and diaphragm assembly 73 Q 2°M*ri986 °- -30- 200368 draws a new volume of liquid from the reservoir or tank 52 back into the upper chamber "E" so that the unit 5 3 is then ready for the next air pulse and jetting action.

For economy and simplification in manufacture and to facilitate assembly and replacement of parts, and referring by way of example to figures10, 11 and 12 particular, the various components comprise a similarly formed diaphragm unit having upper and 10 lower substantially identical parts (at least identical in initial mouldings) with a frusto-conical portion 55a merging into a hollow cylindrical portion 55b having an initially closed end 55c and inner boss 55d; and the outer peripheral flange part 55e 15 (between opposed similar flange parts 55e the peripheral edge portion of the diaphragm 70a is sealably located) is provided with a plurality of stepped lug formations 55f equally spaced about the periphery and of width fractionally less than the gap 20 between adjacent pairs of lugs. This arrangement provides that by locating two similar parts in opposition the projecting lugs 55f of one part can be located between the projecting lugs 55f of the opposite part in a variety of locations and the 25 stepped formations of the lugs 55f provides that the inner stepped faces are located in slight spaced relationship relative to the same transverse plane 200968 i.e. the line of the diaphragm 70a, and the two parts may be readily locked together by locating a ring of wire 76 around the opposed peripheral flange portions and between the said inner faces of the opposed lugs (the arrangement being particularly shown in the fragmentary plan view of figure 12 of encircled portion "X"). This arrangement provides for rapid and simple assembly without fastening screws or bolts, and a readily removable arrangement for servicing as may be 10 required.

The various units may be further provided with a similar piston arrangement comprising two similar half pistons 70 located one either side of the flexible resilient diaphragm 70a and secured 15 thereto such as by locating screws extending between the two piston parts 70 and/or by utilising a suitable adhesive.

The valve unit 54 preferably operates along similar lines to that described with reference to 20 figures 2 and 3 of the drawings with alternate compression and closing off and release to open of parts of flexible hoses 59, 59a passing through the respective cylindrical portions of the diaphragm unit housings; and in the constructions illustrated 25 in figures 10 and H, compression members 69b are slidably located in the piston parts 69 and arranged to extend through openings provided in the ends there-32- 200963 of for engagement with the respective flexible hose parts 59, 59a. In this arrangement there is a central aperture provided through the diaphragm 69a and a single compression spring 77 located between the two compression parts 69b so as to normally bias such parts 69b outwardly in providing the required closing off but resilient compressing force, and the required arrangement whereby with one hose part open the other hose part is fully closed,and there is the intervening time when both hose parts are closed with the piston 69 and diaphragm 69a centralised and the compression parts 69b in their maximum extended positions under the spring 77 influence.

The frusto conical parts of the diaphragm housing can be also provided in forming (such as by injection moulding of rigid setting plastics materials or die casting of aluminium alloys) with a plurality of thickened recessed boss parts 55g, any one or more of which can be opened to form required air inlet and/or outlet ports; and similarly the cylindrical portion 55b can be thickened at opposite side parts for added strength where required to accept flexible hose parts passing through formed apertures, or for the fitment of hose or conduit end connections. Thus a single moulding of one housing half can be employed in a variety of diaphragm pump or valve units.

I 0* 20 25 '•... V ^00 96s The installation can additionally include further animal treatment equipment such as a cow teat and udder spray applicator for the treatment or control of such as materials; and accordingly the cabinet 51 or a similar adjacent cabinet can house a further tank or container for the required treatment liquid and one or more additional liquid diaphragm pump units similar to the previously described units formed with the same housing, diaphragm and piston components. Other liquid pumping and/or valve units similar to the described and illustrated units 55 and 54 can be provided for other treatments and uses; and it will be seen that the diaphragm pump and/or valve units in accordance with the invention can have applications in fields other than those described.

Referring now by way of example to figure 15 of the drawings the apparatus can include a system having a main or first reservoir S' for the principal drenching liquid coupled to the control diaphragm valve unit 54 and diaphragm pump unit 55, with a feed line 61' for a drench gun or guns either directly therefrom or by way of the aforementioned booster or header unit 58 having the supplementary valve unit 54' and pump unit 55'; and additionally there is provided a secondary reservoir S" arranged to contain an additive liquid drench or medicine such as a bloat oil for the treatment of bloat in cows, being a liquid that does or may not readily mix with the first or principal liquid drench. This 200968 second reservoir S" can be arranged to feed prescribed quantities of the bloat oil or other liquid to the principal drench system by way of a feed line L3, non-return or one-way valves, V' and V", and an intermediate diaphragm pump unit 55" similar to pump unit 55. The line L3 from the pump unit 55" and second valve V" feed to the first pump unit 55 (or alternatively to the supplementary pump 55" when provided) so as not to mix with the main drench before ready for dispensing by way of the drench gun G or 60 (preferably the latter kind). The second valve unit V" has a strong return spring arrangement to counter the pressure applied to and prevent passage of the principal drench into the bloat drench system.

Thus, by this invention, there is provided an effective and efficient means for dispensing animal drenches, and in particular liquid drenches which may be admixtures and tend to settle out when not agitated and which are otherwise frequently difficult to dispense with normal drench apparatus having conventional valving and dispensing arrangements . Particular forms and variations of the invention have been described and illustrated by way of example, but it will be appreciated that other variations of and modifications to the invention can take place without departing from the scope of the appended claims. For example the apparatus has been described with reference to the operation of one drench or dispensing ^ 200968 gun, but it is envisaged that two or more dispensing guns can be supplied from the same supply source and from the same pumping and pump valve and control valve means by appropriate multiple connections 5 and/or switching valve mechanisms for the drench outlet line and control valve air line.

Also, it is envisaged that in some cases it may be preferable to employ vacuum pressure in place of air pressure and/or to utilise piston and cylinder 10 units in place of diaphragm units. Electric solenoid operated switching valve mechanisms may also be conveniently alternatively employed at appropriate parts of the apparatus.

Further, the invention is not confined to 15 the application of drenches as it is envisaged that the supply tank and agitating means and/or the other pumping and valve control components may have applications elsewhere in the dispensing of difficult materials.

•:V 200968

Claims (23)

WHAT WE CLAIM IS:

1 . A means for dispensing liquid and/or liquidised materials (as herein defined) in prescribed amounts comprising a pump unit housing a reciprocally movable diaphragm and/or piston unit defining a wall of a pumping chamber of the pumping unit and actuable by an intermittently applied force, an inlet to said chamber arranged for connection via first valving means to a supply source of the material to be dispensed and an outlet from the chamber arranged for connection via second valving means to a dispensing nozzle device; said first and second valving means being synchronized for alternate opening and closing in conjunction with movement of the diaphragm and/or piston unit for induction to and expulsion from the pump chamber of the material, and said first and second valving means including resilient flexible tube parts which are alternately compressible to prevent the flow of the material therethrough.

2. A means as claimed in claim 1 wherein said flexible tube parts of the first and second valve means are alternately compressible by a common reciprocally movable member.

3. A means as claimed in claim 1 or claim 2 wherein the pump unit and first and second valving means are all diaphragm units.

4. A means as claimed in claim 4 wherein a diaphragm actuated control unit is provided for effecting sychron- >^ized operation of the diaphragm pump and valve units. -37-

5. A means as claimed in any one of the preceding claims and applied to a drench administering system substantially as hereinbefore described with reference to figure 1 of the accompanying drawings.

6. A means as claimed in claim 1 or claim 2 wherein the first and second valving means are provided by way of a single diaphragm unit having two similar opposed housing parts with a resilient diaphragm member clamped peripherally therebetween to form two separated chambers, the medial part of said diaphragm member supporting a compression member extending into each chamber and arranged for co-axial movement together on the application of air pressure or vacuum to the respective chambers, one of said resilient flexible tube parts being located in one chamber and the other of said flexible tube parts being located in the other chamber of the diaphragm unit to be alternately compressed by movement of said diaphragm and respective compression member.

7. A means as claimed in claim 6 wherein said compression members are provided with or incorporate one or more compression springs providing for a controlled resilient compression force to be applied to the flexible tube parts within the diaphragm valve unit.

8. A means as claimed in claim 7 wherein the resilient mounting of the compression members provides an overlap period during movement of the diaphragm and compression members whereby both flexible tube parts 200938 are compressed closed before either one of said tube parts are released from the compressed closed state to the uncompressed open state permitting passage of fluid therethrough.

9. A means as claimed in claim 6, claim 7 or claim 8 wherein the diaphragm unit forming the first and second valving means is arranged and constructed and operated substantially as hereinbefore described with reference to figures 2 and 3 of the accompanging drawings.

10. A means as claimed in claim 6, claim 7 or claim 8 wherein the diaphragm unit forming the first and second valving means is arranged and constructed and operated subtantially as hereinbefore described with reference to figures 10 and 11 of the accompanying drawings.

11. A means as claimed in any one of the preceding claims wherein the dispensing nozzle device is a drench hand gun or hand piece arranged and constructed and operated substantially as hereinbefore described with reference to figures 1 and 5 of the accompanying drawings.

12. A means as claimed in any one of claims 1 to 10 inclusive wherein the dispensing nozzle device is a drench gun or hand piece arranged and constructed and operated substantially as hereinbefore described with reference to figure 9 of the accompanying drawings.

13. A means as claimed in any one of the preceding claims wherein the supply source for the liquid or liquidised material to be dispensed comprises a reservoir and agitation means are incorporated in the system for intermittent or continuous agitation of the reservoir contents during operation of the means. - 39- 200968

14. A means as claimed in claim 13 wherein the reservoir is constructed substantially as hereinbefore described with reference to figure 6 of the accompanying drawings.

15. A means as claimed in claim 13 or claim 14 wherein the agitation of the reservoir contents is arranged to be effected substantially as hereinbefore described with reference to figures 6 and 7 of the accompanying drawings.

16. A means as claimed in claim 13 wherein agitation of the reservoir contents is arranged substantially as hereinbefore described with reference to figures 1,13 and 14 of the accompanying drawings.

17. A means as claimed in any one of claims 1 to 16 wherein a "brake" or "stop" valve substantially as described with reference to figure 4A of the accompanying drawings is employed.

18. A means as claimed in any one of claims 1 to 16 wherein a deceleration valve substantially as described with reference to figure 4B of the accompanying drawings is employed in the system.

19. A means as claimed in any one of claims 1 to 4 inclusive and any one of claims 6 to 8 inclusive, wherein the pump unit and the first and second valving means are arranged and constructed and operated substantially as hereinbefore described with reference to figures 10, 11 and 12 of the accompanying drawings.

20. A means as claimed in any one of claims 1 to 4 inclusive and any one of claims 6 to 8 inclusive, when applied to an animal drench system substantially as -4.0- £00966 hereinbefore described with reference to figures 8 to 14 of the accompanying drawings.

21. A means as claimed in claim 20 and including a supplementary liquid medicine administering system substantially as hereinbefore described with reference to figure 15 of the accompanying drawings.

22. A diaphragm housing for the means according to any one of the preceding claims arranged and constructed and assembled substantially as hereinbefore described with reference to figures 11 and 12 of the accompanying drawings.

23. A drench administering assembly including a reservoir and diaphragm pump and valving means arranged substantially as hereinbefore described and with reference to figure 14 of the accompanying drawings. ENGINEERING DYNAMICS LIMITED, By Their Authorised Attorneys/ JOHN A. REMMINGTON & ASSOCIATES, 6*' -41-