Fluid Dispenser

Abstract

A fluid dispenser having a fluid inlet and a fluid outlet; and a pump for drawing fluid from a fluid source via the fluid inlet towards the fluid outlet; wherein the pump has a housing and a spring adapted to bias the pump away from a compressed position and towards a rest position; the spring being situated at least partially within the housing; and wherein the spring comprises one or more resiliently deformable polymer units.

Claims

1. A fluid dispenser comprising: a fluid inlet and a fluid outlet; a pump for drawing fluid from a fluid source via the fluid inlet towards the fluid outlet; wherein the pump has a push top with an external wall which surrounds the upper portion of a spring; said push top being displaceable within a housing; said spring being adapted to bias the pump away from a compressed position and towards a rest position; the spring being, whilst in use, wholly internal as it is situated entirely within the combination of said push top and said housing; wherein the spring is wholly formed of one or more resiliently deformable polymer units; and said polymer units surround a stem through which fluid is drawn between said fluid inlet and said fluid outlet; said stem extending along the entire length of said spring; whereby said stem separates said spring from said fluid.

2. A fluid dispenser according to claim 1, wherein each unit of the spring has a circumferential wall and the circumferential wall is substantially without a cavity.

3. A fluid dispenser according to claim 1, wherein the or each unit is a gas-fillable unit.

4. A fluid dispenser according to claim 2, wherein the spring has a substantially non-helical arrangement.

5. A fluid dispenser according to claim 4, wherein the spring comprises a plurality of vertically stacked units which are joined to one another such that the spring is formed as a single piece.

6. A fluid dispenser according to claim 5, wherein each unit has a substantially circular vertical cross section.

7. A fluid dispenser according to claim 5, wherein the spring is substantially concertinaed.

8. A fluid dispenser according to claim 7, wherein the spring is entirely contained within the housing.

9. A fluid dispenser according to claim 8, wherein adjacent units of the spring are in fluid communication with one another.

10. A fluid dispenser according to claim 9, wherein the spring is sealed from the outside environment.

11. A fluid dispenser according to claim 10, wherein the spring has a substantially constant diameter along a longitudinal axis of the spring.

12. A fluid dispenser according to claim 1, wherein the or each unit of the spring comprises an equator, the equator of the or each unit being perpendicular to a longitudinal axis of the spring.

13. A fluid dispenser according to claim 12, wherein the thickness of the or each unit is substantially constant along the length of the spring.

14. A fluid dispenser according to claim 13, wherein the thickness of the or each unit varies along the length of the spring.

15. A fluid dispenser according to claim 4, wherein the spring is coated with a non-stick coating.

16. A fluid dispenser according to claim 1, wherein the spring is made of an elastomer.

17. A fluid dispenser according to claim 1, wherein the spring is made of a thermoplastic elastomer.

18. A fluid dispenser according to claim 1, wherein the spring is made from material selected from the group of: a polyolefin blend (TPO); a polyolefin alloy (TPV); a polyolefin plastomer (POP); a polyolefin elastomer (POE); reactor TPO (R-TPO); a thermoplastic polyolefin; an olefin block copolymer.

19. A container comprising a fluid dispenser as provided by claim 1.

20. A container according to claim 19, wherein the container is an airless container.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0089] The invention will now be described, by way of example only, with reference to the accompanying drawings.

[0090] FIG. 1A shows a fluid dispenser in cross section;

[0091] FIG. 1B shows the fluid dispenser of FIG. 1A in cross section with a full side view of a spring.

[0092] FIG. 2 shows a side elevation view of a spring;

[0093] FIG. 3 shows a side perspective view of a spring having four adjacently arranged units.

[0094] FIG. 4 shows a part cross sectional view of a spring having two adjacently arranged units.

[0095] FIG. 5 shows a dispenser in cross section with a spring in side elevation along its longitudinal axis.

[0096] FIG. 6 shows a perspective view of a spring having three lobes defining three channels for the flow of fluid.

[0097] FIG. 7 shows a cross section of a spring having lobes defining channels for the flow of fluid.

[0098] FIG. 8 shows an airless container and fluid dispenser in cross section.

[0099] FIG. 9 shows a further fluid dispenser in cross section.

[0100] FIG. 10 shows a spring having cavities in cross section.

[0101] FIG. 11 shows a further fluid dispenser in cross section.

[0102] FIG. 12 shows a spring without cavities in cross section.

[0103] FIG. 13 shows a further fluid dispenser in cross section.

[0104] FIG. 14 shows a side view of a spring for a fluid dispenser.

[0105] FIG. 15 shows a further embodiment of a spring.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0106] FIG. 1A shows a fluid dispenser 10 for drawing fluid from a fluid source (not shown) via a fluid inlet 12 and urging fluid towards a fluid outlet 14. The fluid dispenser may be used for various fluid products, such as soaps, cosmetics and food products.

[0107] The fluid dispenser 10 comprises a fluid chamber 16 and a tube 18. The tube 18 is in fluid communication with the fluid chamber and extends from the fluid chamber 16 towards, in use, a fluid source. The fluid chamber 16 and tube 18 are separated by a valve 20. The valve 20 is a one-way valve which allows fluid to pass from the tube 18 into the fluid chamber 16 but not from the fluid chamber 16 to the tube 18. In the embodiment of FIG. 1A the valve 20 comprises a ball 22 and a narrowed section of the tube 18 which together reversibly form a seal. In use, when the pressure in the fluid chamber 16 is greater than the pressure in the tube 18, a seal is formed between the ball 22 and tube 18 because the ball 18 is forced against the narrowed section of the tube 18.

[0108] The dispenser 10 further comprises a pump 24. The pump 24 incorporates a stem 26 which is in fluid communication with and moveable in relation to the fluid chamber 16 along a longitudinal axis of the dispenser 10. The stem 26 has a channel extending between the fluid chamber 16 and the fluid outlet 14. The pump 24 also incorporates a push top 28 which acts as a pump actuator.

[0109] The fluid outlet 14 is formed as a spout which is integral with the push top 28. The push top 28 is shaped so that the thumb or finger of an operator can comfortably rest on the push top 28 and apply pressure to the pump 24.

[0110] The pump 24 is arranged to urge fluid contained in the fluid chamber 16 up the channel of the stem 26 and out of the fluid outlet 14 as the push top 28 is depressed, i.e. as the pump 24 is moved towards the compressed position against the action of a spring 30. The spring 30 acts to return the pump 24 to the rest position by biasing the pump actuator 28 and fluid chamber 16 apart from one another.

[0111] The push top 28 and stem 26 are fixed to one another and both moveable relative to the fluid chamber 16. In use, an operator applies force to the push top 28 to move the stem 26 downwards. As the push top 28 and stem 26 are moved downwards, the spring 30 is compressed and pressure inside the fluid chamber 16 is increased. The increase in pressure causes fluid retained in the fluid chamber 16 to pass through the stem 26 towards the fluid outlet 14. The increased pressure also closes the valve 20 to prevent fluid from passing from the fluid chamber 16 into the tube 18.

[0112] When force is released from the push top 28, the spring 30 acts to move the pump 24 towards the rest position, i.e. move the fluid chamber 16 and the pump actuator 28 away from one another. The reduced pressure caused by the spring 30 causes air to enter the fluid outlet 14. The reduced pressure also causes the valve 20 to open and allow fluid to enter the fluid chamber 16 from the tube 18. Thus, the fluid chamber 16 refills with fluid from the fluid source ready for the pump 24 to be used again.

[0113] The pump 24 and fluid chamber 16 are enclosed by a housing 32. The housing 32 extends around the circumference of the pump 24 and fluid chamber 16. The housing 32 further comprises a collar 34 for receiving the neck of a container (not shown). The collar 34 incorporates a female screw socket for cooperating with the thread of a container with a screw top. The fluid chamber 16 is shaped so as to sit at least partially within and be bounded by an upper portion of a container.

[0114] The spring 30 comprises a plurality of gas-fillable units, such as 38, made of resiliently deformable material. The or each unit of the spring 30 has an elasticity which causes the spring 30 to return to its original shape after a force has been applied to it.

[0115] Each of the units of the spring 30 is integrally formed with an adjacent unit. The spring of FIG. 1A comprises eight units which are stacked one on top of the other and are all in fluid communication with one another. The spring 30 is sealed from the outside environment. In other words, a volume of gas is contained in the spring 30 and the resiliently deformable material of the spring 30 allows the spring to be compressed under pressure and to return to a resting shape when pressure is released. The spring 30 has a top end and a bottom end and the spring 30 is sealed at each end. The size of the spring 30, number of units incorporated in the spring 30, the thickness of the or each unit 38 and the resting pressure of the spring 30 can each be modified to adjust the performance of the fluid dispenser 10.

[0116] The spring 30 of FIG. 1A and FIG. 1B is annular, i.e. ring shaped, and the stem 26 extends through the opening of the spring 30.

[0117] FIG. 1B shows a side view of the spring 30 not in cross section and the rest of the dispenser 10 in cross section. The spring 30 can straightforwardly occupy the position of a conventional helicoidal spring.

[0118] In the fluid dispenser 10 of FIGS. 1A and 1B, the pump 24 comprises a cavity 36 between the housing 32 and the stem 26, and the spring 30 is located within the boundary of the housing 32 and within in the cavity 36. The cavity 36 has a shape which is suitable to accommodate the spring 30 when the pump 24 is in the rest position and when the pump 24 is in the compressed position. In other words, the cavity 36 is long enough to accommodate an uncompressed spring 30 and wide enough to accommodate a compressed spring 30 where each of the units temporarily increases in diameter.

[0119] FIGS. 2 and 3 show two embodiments of a spring 30 which may be incorporated in the fluid dispenser of FIGS. 1A and 1B.

[0120] FIG. 2 shows a side view of a first embodiment of a spring 30 comprising four units 38. The units 38 are integrally formed and in fluid communication with one another. Girdles 40 extend around the units to reinforce the spring 30. The dotted lines on FIG. 3 show how the units 38 are integral with one another. The spring 30 may be sealed from the outside environment or in fluid communication with the outside environment.

[0121] Each unit 38 of the spring 30 of FIG. 2 has a circumferential wall 58 having a substantially constant diameter. The diameter of the wall 58 decreases towards a top end and a bottom end of the unit 38. Each unit 38 has an equator 60 which has a constant diameter.

[0122] FIG. 3 shows a perspective view of a second embodiment of a spring 30 comprising two units 38 which are integrally formed and in fluid communication with one another. The spring 30 does not comprise reinforcing girdles. Each unit 38 of the spring 30 of FIG. 3 also has an equator which has a substantially constant diameter. The diameter of each unit 38 decreases towards the top end and bottom end of the unit.

[0123] The springs 30 of FIGS. 3 and 4 are annular and comprise an opening 42 (shown only in FIG. 4). A stem of a fluid dispenser 10 may extend through the opening 42. The units 38 of the spring 10 are sealed from the opening 42.

[0124] FIG. 4 shows a spring 30 in cross section and being sealed at top and bottom ends. FIG. 4 shows the spring 30 in a relatively compressed position. The spring 30 is annular and comprises an opening 42 through which a stem 26 (shown by the dashed line) can extend. The spring 30 is sealed from the opening 42. The top and bottom ends of the spring 30 are each sealed by a support plate 44.

[0125] FIG. 5 shows another embodiment of a fluid dispenser 10 sharing most of the features of the fluid dispenser 10 of FIGS. 1A and 1B. The fluid dispenser 10 of FIG. 5 differs from the fluid dispenser of FIGS. 1A and 1B in that it does not comprise a cavity between the housing 32 and the stem 26. Instead, the spring 30 is located inside the fluid chamber 16.

[0126] The spring 30 extends between an end portion of the stem 26 and an end of the fluid chamber 16 which is substantially opposite to the stem 26.

[0127] In the fluid dispenser 10 of FIG. 5, to allow fluid to pass from tube 18 into the fluid chamber 16 and from the fluid chamber 16 into the stem 26, the spring 30 comprises channels (not shown) at the periphery of the spring 30. Each unit of the spring 30 has a series of lobes which extend around the circumference of the spring 30. The lobes of adjacent units of the spring 30 are aligned to form the channels through which fluid can flow.

[0128] In use, when pressure is applied to the push top 28 the stem 26 is forced downwards into the fluid chamber 16. The downward movement of the stem 26 increases the pressure within the fluid chamber 16. The increased pressure forces the valve 20 to close and fluid contained in the fluid chamber 16 to exit via the stem 26. The channels formed by the lobes of the units of the spring 30 allow the fluid to flow from the fluid chamber 16 into the stem 26 and eventually out of the fluid outlet 14.

[0129] When pressure is applied to the push top 28 ceases, the spring 30 acts to return to the pump to the rest position. The spring 30 causes the pressure in the fluid chamber 16 to decrease, which opens the valve 20 thereby drawing fluid into the fluid chamber 16 via the tube 18. Once the pump 24 is in the rest position the dispenser 10 is ready to be used again.

[0130] The pump 24 may also be forced back towards the compressed position from a position which is between the rest and compressed positions.

[0131] FIG. 6 shows a spring 30 having a single unit in perspective. The spring 30 comprises a circumferential wall 58. The circumferential wall 58 incorporates changes in diameter to form three lobes 62. The lobes 62 together define three channels 64 therebetween. Fluid may thus flow along the channels 64 between the valve 20 and the stem 26 of the fluid dispenser 10.

[0132] FIG. 7 shows a spring 30 in cross section, having a plurality of lobes 62 formed by changes in circumferential diameter of the spring 30. The lobes 62 define a plurality of channels 64 through which fluid may flow in use. The spring 30 also incorporates an opening 42 through which the stem 26 of a fluid dispenser, or fluid, may flow in use.

[0133] FIG. 8 shows an airless container 50 and fluid dispenser 10 in cross section. The container 50 comprises a fluid chamber 52 and a fluid chamber plate 54. The fluid chamber 52 contains a fluid to be dispensed and no air. The dispenser 10 comprises a pump 24 incorporating a spring 30. The spring 30 biases the pump 24 towards a rest position. As the pump 24 is actuated against the bias of the spring 30 fluid is drawn from the fluid chamber 52 to a fluid outlet 14. The fluid chamber plate 54 is moveable along the length of the container 50 and moves up the length of the container 50 in response to fluid exiting the fluid chamber 52 via the fluid outlet 14. The container 50 further comprises an air intake valve 56. Air enters the air intake valve 56 as the fluid chamber plate 54 rises inside the fluid chamber 52 to replace the space left by the now expelled fluid. This way, a vacuum-type condition is maintained within the container 50.

[0134] FIG. 9 shows a cross section of a fluid dispenser sharing most of the features of the dispenser of FIGS. 1A and 1B. The spring 30 of the fluid dispenser of FIG. 9 also has a plurality of gas-fillable units 38, wherein each unit of the spring 30 comprises a circumferential cavity. The units 38 are stacked vertically one on top of another to form the spring 30 and adjacent units 38 are in fluid communication with one another, as shown in FIG. 10. Fluid communication may be achieved by an appropriate passage-way or aperture between adjacent portions.

[0135] FIG. 11 shows a further fluid dispenser 10. The fluid dispenser 10 of FIG. 11 differs from the fluid dispensers of FIGS. 1A, 1B and 9 in that the spring 30, which is shown in greater detail in FIG. 12, comprises a plurality of resiliently deformable polymer units 38 which are each solid. In other words, each unit 38 of the spring 30 is substantially without a cavity. Therefore, the units 38 are not in fluid communication with one another or the outside environment. The units 38 are stacked vertically one on top of another and are housed entirely inside the housing 32 of the dispenser 10. The spring 30 is housed in a cavity 36 between the housing 32 and the stem 26. In a further embodiment, the spring may be a polymeric foam.

[0136] With reference to FIG. 12, the spring 30 has a non-helical arrangement. Each unit 38 has a substantially circular vertical cross section and is substantially ring shaped to form the opening 42 through which the stem of a fluid dispenser 10 extends.

[0137] FIG. 13 shows a further fluid dispenser 10 having a spring 30 which is entirely housed within the housing 32.

[0138] The spring 30, shown in greater detail in FIG. 14, comprises a plurality of resiliently deformable polymer units 38 which are each substantially without a cavity. The spring 30 has a concertinaed arrangement. Each unit 38 comprises a top and bottom ends. The circumferential wall of each unit decreases in diameter towards each end of the unit 38. Each unit 38 thus has an equator which is substantially perpendicular to the longitudinal axis of the fluid dispenser 10. In other words, the spring comprises a succession of portion which are frustoconical where adjacent frustoconical portions taper in opposite directions. The succession of the portions allows the spring to collapse on itself under appropriate pressure and return to its starting configuration once pressure ceases to be applied.

[0139] FIG. 15 shows an alternative configuration to the succession of frustoconical portions. Instead, the wall of the spring undulates as a succession of radiused portions which have alternatively an outer opening or an inner opening. These rounded sections are thus also susceptible to being collapsed when appropriate pressure is applied and then return to their original position once the pressure ceases to be applied for example once the fluid has been dispensed.