Patent Publication Number: US-9833798-B2

Title: Dispenser

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the priority of Australian Provisional Patent Application No. 2014900800, filed Mar. 10, 2014, the disclosure of which is incorporated herein by reference. 
     FIELD 
     The present invention relates to dispensers that delivers a liquid, and more particularly but not exclusively to a dispenser that will deliver a liquid medication to animals, such as companion animals. 
     BACKGROUND 
     There are a variety of means via which a liquid, such as a medication, can be delivered to an animal, such as a companion animal. For example, the medication may be delivered via a collar, orally via tablet, or in some instances a “spot-on” applicator. A particular example of an applicator is a satchel that is compressed to expel the contents from the satchel. 
     In use of pump delivery devices, the reservoirs are open to atmosphere in order for the pumps to be able to draw liquid from the reservoir. This can lead to contamination of the liquid being dispensed. 
     Further disadvantages of the devices/methods that dispense a medication to an animal include inaccuracies in the dose volume, efficiency of the medication due to the method of delivery, as well as difficulty in respect of applying the medication. 
     OBJECT 
     It is the object of the present invention to overcome or substantially ameliorate at least one of the above disadvantages. 
     SUMMARY OF INVENTION 
     There is disclosed herein a dispenser to deliver a liquid, the dispenser including: 
     a reservoir having an interior to receive a volume of the liquid; 
     a pump communicating with the reservoir to draw the liquid from the reservoir; an inlet one-way valve between the reservoir and pump via which liquid passes from the reservoir to the assembly; 
     a delivery passage, to receive liquid from the pump, to deliver the liquid to a delivery outlet via movement of the liquid in a delivery direction; 
     an outlet one-way valve operatively associated with the pump and delivery passage; 
     a vent one-way valve providing for the flow of air from atmosphere to said interior; and wherein 
     the inlet and outlet one-way valves operate to provide for the flow of liquid in said delivery direction from the reservoir to the delivery outlet while inhibiting movement of the liquid in a direction opposite said delivery direction. 
     Preferably, the reservoir includes a hollow body providing said interior, with said pump being fixed to said hollow body, and wherein said vent one-way valve is attached to the pump and communicates with said interior. 
     Preferably, said body has a base upon which the dispenser can rest, with said vent one-way valve being spaced from said base. 
     Preferably, said vent one-way valve is positioned so as to be above the liquid when the dispenser is resting on said base. 
     Preferably, said vent one-way valve is formed of resilient material and is urged closed, but resiliently deforms to open when pressure in said interior is below atmospheric pressure. 
     There is further disclosed herein a dispenser to deliver a liquid, the dispenser including: 
     a pump assembly providing a pump chamber having a pump inlet, and an outlet passage extending from the chamber to an outlet opening, a piston in the chamber cooperating with the chamber to generally enclose a pump volume, with relative movement between the chamber and piston changing said volume to deliver the liquid in a delivery direction to the outlet passage, with said dispenser further including; 
     an inlet one-way valve operatively associated with the pump inlet to provide for the delivery of the liquid thereto while inhibiting movement of liquid through the inlet valve in a direction opposite said delivery direction; 
     an outlet one-way valve operatively associated with the outlet passage to provide for the delivery of the liquid to the outlet opening, while inhibiting movement of the liquid along the outlet passage in said opposite direction; and wherein 
     the inlet valve includes a movable valve element, the movable valve element being movable between an open position and a closed position, with the element in the closed position preventing movement of the liquid in said opposite direction, while in the open position providing for the delivery of liquid to the chamber, with said element being urged to the closed position when said passage is generally upwardly oriented and said direction is generally upwardly oriented. 
     Preferably, said element is urged to the closed position under the influence of gravity when the passage is generally upwardly oriented. 
     Preferably, the dispenser further includes a spring urging the element to the closed position. 
     Preferably, said pump including a pump cylinder within which the piston is located, with the pump cylinder providing the pump inlet. 
     Preferably, the dispenser further includes a reservoir having an interior to receive the liquid, and a vent one-way valve providing for the flow of air from atmosphere to said interior when pressure in said interior is less than atmosphere. 
     A dispenser, further including a pump assembly said pump assembly including: 
     a pump body providing a pump cylinder; 
     a piston slidably mounted in the cylinder and co-operating therewith to provide a pump chamber; 
     the vent one-way valve; 
     the outlet one-way valve; 
     the inlet one-way valve, and 
     a nozzle attached to the piston, with the nozzle and reservoir gripped by a user to cause relative movement therebetween to cause the liquid to be delivered. 
     Preferably, the reservoir includes a hollow body with a neck, and said pump assembly is mounted on the neck to act as a cap closing said neck. 
     Preferably, the pump body has a threaded sleeve, and said neck is threaded and engaged with the sleeve. 
     Preferably, the pump body provides an annular cavity, between the sleeve and cylinder, that receives said neck. 
     Preferably, the cylinder has an inner transverse wall providing a location for the inlet one-way valve, with said vent one-way valve being mounted on the transverse wall. 
     Preferably, the inlet valve includes a movable valve element, the movable valve element being movable between an open position and a closed position, with the element in the closed position preventing movement of the liquid in said opposite direction, while in the open position providing for the delivery of liquid to the chamber, with said element being urged to the closed position when said passage is generally upwardly oriented and said direction is generally upwardly oriented. 
     Preferably, said element is urged to the closed position under the influence of gravity when the passage is generally upwardly oriented. 
     Preferably, the dispenser further includes a spring urging the element to the closed position. 
     Preferably, said pump including a pump cylinder within which the piston is located, with the pump cylinder providing the pump inlet. 
     Preferably, the dispenser further includes a reservoir having an interior to receive the liquid, and a one-way valve providing for the flow of air from atmosphere to said interior when pressure in said interior is less than atmosphere. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       Preferred forms of the present invention will now be described by way of example with reference with the accompanying drawings wherein: 
         FIG. 1  is a schematic side elevation of a dispenser; 
         FIG. 2  is a schematic sectioned side elevation of the dispenser of  FIG. 1  sectioned along the line  2 - 2 ; and 
         FIG. 3  is an enlarged view of portion of the dispenser as seen in  FIG. 2 . 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     In the accompanying drawings there is schematically depicted a dispenser  10 . As one example, the dispenser  10  may be a metered pump device that can deliver multiple metered doses. As a further example, the dispenser  10  may be a “spot-on” delivery device that delivers a medication to companion animals. 
     The dispenser  10  includes a hollow body  11  providing a reservoir. The body  11  encloses an interior  12  that receives a liquid, such as a medication to be dispensed. 
     At one end of the body  11  there is provided a threaded neck  13 , while at the opposite end the body  11  has a base  14  upon which the dispenser  10  can rest on a supporting surface. When resting on the base  14 , the longitudinal central axis  15  is generally upwardly extending from the base  14 . 
     Mounted on the neck  13  is a pump assembly  17 . The pump assembly  17  is adapted to draw liquid from the interior  12  and dispense metered doses of the liquid. The pump assembly  17  includes a body  18  providing a cylindrical sleeve  19  that is internally threaded and threadably engaged with the neck  13 . The body  18  also has a radially extending annular flange  20  that extends inwardly toward the axis  15  from the sleeve  19 . Extending from the flange  20  is a further sleeve  21 . Liquid moves through the pump assembly  17  in a delivery direction  52 . 
     The pump assembly  17  further includes a pump  57  provided by a cylinder  22  and piston  50 . The cylinder  22  abuts an internal surface of the flange  20  and is located internally relative to the sleeve  19 . The cylinder  22  includes a cylindrical surface  23  that surrounds a pump chamber  24 . The cylinder  22  includes an annular cavity  25  from which there extends a passage  26 . The cavity  25  communicates with atmosphere. 
     Located in the chamber  24  and slidably engaged with the surface  23  is the piston  50  that includes an O-ring  27  that sealingly connects the piston  50  with the surface  23 . 
     The piston  50  includes an axially extending sleeve  28  that is located internally relative to the sleeve  21 . 
     Attached to the piston  50 , by being fixed to the sleeve  28 , is a nozzle member  29 . The nozzle member  29  includes an elongated nozzle  30  having a longitudinal passage  31  that communicates with an end opening  32  via which the liquid is dispensed, preferably in a spray form. 
     The member  29  further includes a sleeve  33  that is fixed to the piston  50  by being secured to the sleeve  25 . 
     Located internally of the sleeve  33  is a chamber  34  that communicates with the passage  31 . Located in the chamber  33  is a spring  35 . 
     The piston  50  has a longitudinal passage  36  having adjacent one and thereof a valve seat  37 . Operatively associated with the seat  37  is a movable valve element  38  having and end portion  39  that engages the seat  37  to close the passage  36 . The element  38  has a stem  40  engaged by the spring  35 . The spring  35  is compressed and urges the movable valve element  38  into seated engagement with the seat  37  to close the passage  36 . The seats  37 , element  38  and spring  35  provide a one-way valve  55  preventing liquid being opposite the direction  52 . 
     The passage  36  communicates with the chamber  24 , and also communicates with the chamber  34  when the valve element  39  is disengaged with the seat  37 . 
     The cylinder  22  has an inlet passage provided by a valve seat  41 . Operatively associated with the valve seat  41  is a movable valve element  42  having an end portion  43  sealingly engageable with the seat  41 . The element  42  also has a stem  44  extending from the end portion  43  and having an annular projection  45 . Extending between the projection  45  and the cylinder  22  is a spring  46 . The spring  46  is compressed so as to urge the element  42  to a closed position, that is with the end portion  43  engaged with the seat  41 . The seat  41 , element  42  and spring  46  provide a one-way valve  56  preventing liquid moving in a direction opposite the direction  52 . 
     The cylinder  22  also has a cylindrical projection  47  providing the passage  26 . Fitted over the projection  47  is a vent one-way valve  48 . Preferably the valve  48  would be formed of resilient material so as to be urged to a closed configuration. However the valve  48  is resiliently deformably (to an open configuration) to provide for the flow of air from the cavity  25 , through the passage  26  to the chamber  24 . 
     The one-way valve  48  is located at a position adjacent the neck  13 , that is one end of the interior  12 . More particularly the one-way valve  48  is located adjacent the pump  51 . Accordingly, when the dispenser  10  rests on its base  14 , the one-way valve  48  is located above liquid level in the interior  12 . 
     The pump assembly  17  is essentially a cap  58  attached to the neck  13 . The pump body  18  not only provides the cylinder  22  but an inner transverse wall  53  (part of the cylinder  22 ) providing the seat  41 . The valve  48  is also mounted in the wall  53 . The body  18  also provides an annular cavity  54 , between the cylinder  22  and sleeve  19 , that receives the neck  13 . 
     Accordingly the pump assembly includes the body  18 , the one-way valves  48 ,  55  and  56 , the piston  50 , and the nozzle  30 . 
     In operation of the above described dispenser  10 , the interior  12  receives a volume of liquid to be dispensed. Preferably, the dispenser  10  is operated so that the nozzle  30  is downwardly extending in the direction  16 . Thereafter a user positions the dispenser  10  so that the body  11  is located in the palm of a user&#39;s hand. The user then by use of one or more fingers engaged with the lateral projection  51  of the nozzle member  29 , moves the nozzle member  29  in a direction opposite the direction  16  relative to the body  11 . This in turn moves the piston  50  relative to the cylinder  22  to reduce volume of the interior  24 . Any liquid contained in the interior  24  will then be under pressure and cause the valve element  38  to move to the open position. Once the element  38  is in the open position, liquid in the chamber  24  flows through the passage  36  to be delivered to the passage  31 , as a result of reduction in the volume of the chamber  24 . The liquid is then dispensed via the end opening  32 . 
     Once a measured dose has been delivered, the user relaxes the pressure applied to the nozzle member  29  (projections  51 ), causing the nozzle member  29  to move in the direction  16  relative to the body  11 . This occurs under the influence of the spring  49  extending between the flange  20  and a flange  59  of the nozzle member  29 . In particular, the spring  49  is under compression when no pressure is applied to the nozzle member  29 . 
     As the piston  50  moves in the direction  16  relative to the body  11 , when pressure is relaxed on the member  29 , via the projections  51 , liquid is drawn into the chamber  24  via the seat  41 . In particular due to a reduction of pressure in the chamber  24 , the end portion  43  of the valve element  42  moves away from the seat  41 . This allows liquid to be drawn in from the interior  12  to the chamber  24 . 
     As liquid is drawn from the interior  12 , air is allowed to enter the interior  12  via the passage  61  and one-way valve  48 . This enables pressure within the volume  12  to be at least approximate atmospheric pressure. 
     An advantage of the above described preferred embodiment is the “equalizing” of pressure in the interior  12  with respect to atmosphere, as provided by the one-way valve  48 . A further advantage of the above described preferred embodiment is that when the dispenser  10  is resting on its base  14 , the movable valve element  42  is urged under the influence of gravity to the closed position when resting on the base  14 , the direction  16  is upward. The element  38  is also urged under the influence of gravity to the closed position when the dispenser  10  is resting on the base  14 . 
     A still further advantage of the above described preferred embodiment is that the one-way valve  48  is located above liquid level when the dispenser  10  is resting on its base  14 , that is with the direction  16  being an upward direction.