HK1087968B - Airless dispensing pump and a method for priming a pump - Google Patents

Description

Airless dispensing pump and filling method thereof

Technical Field

The present invention relates generally to airless dispensing pumps and more particularly, but not exclusively, to an airless dispensing pump that can be easily primed (Prime) to effectively pump viscous fluids while reducing contact with contamination sources such as air and metal.

Background

Airless pumps have been developed for use in a wide range of applications, including dispensing personal care products such as skin creams, lotions, toothpaste and hair gels, as well as food sauces and the like. Many of these products deteriorate quickly upon contact with air and it is therefore important to prevent air from entering the package when the product is dispensed. In a typical dispensing pump application, air is allowed to enter the container via the vent passage in order to equalize the pressure inside the package as the product is dispensed. If this is not the case, the container may become progressively flattened or, in the case of a rigid container, the increased vacuum level within the container will exceed the ability of the dispensing pump to draw product from the container.

The ability to evacuate the entire contents of the container in the case of viscous products is relatively weak when using conventional dispensing pumps with a straw or tube. Generally, a viscous product, such as cream, is drawn through a straw, which initially works, but the viscous product does not self-balance. As a result, a cavity or hole is formed in the surface of the product, at which point the dispensing pump can only dispense air, since it cannot dispense product that adheres to the sidewall of the container. As a result, only about 50% to 60% of the total package capacity of viscous product can be dispensed by conventional dispensing pumps.

In airless type dispensing systems, the above problems are overcome in two general ways, namely by using a variable flat bag type design or by using a driven piston type design. In a variable flat design, a flat bag is connected to the dispensing pump, the bag being gradually flattened as the contents are discharged. In a slave piston type design, a rigid container, typically cylindrical or oval, has a slave piston that gradually reduces the volume of the container as the product is drawn by the dispensing pump.

In either type of airless dispensing system, initial priming of the pump mechanism can be somewhat difficult due to the viscosity of the contents. Even after proper filling, the pump mechanism may not dispense a sufficient amount of fluid due to restrictions within the pump mechanism, particularly the valves. When used with viscous products, the valves within the pump mechanism need to provide a large flow opening, but at the same time close quickly to ensure that the product is pumped efficiently. Due to the differences in viscosity of the various products, it is difficult to easily and inexpensively reconfigure the pump mechanism to accommodate products of different performance. Many products, such as pharmaceuticals, must also be free of metal contact that could contaminate the drug, and it is desirable to reduce or even eliminate contact with metal parts within the pump mechanism. In a typical airless pump design, after dispensing, the product may remain at the outlet of the dispensing head where it may become dry or hardened from contact with air. The dried product often has an unsightly appearance and sometimes results in a clogged outlet. Therefore, improvements in this regard are needed.

Disclosure of Invention

One aspect of the present invention relates to an airless dispensing pump assembly. The assembly includes a pump mechanism that forms a pump chamber with an inlet port through which a viscous fluid can be supplied from a container. The pump mechanism includes a piston slidably received in the pump chamber to pump fluid from the pump chamber. The outlet valve member is configured to allow the viscous fluid to flow out of the pump chamber during a dispensing stroke of the piston and to create a vacuum in the pump chamber during an intake stroke of the piston. An inlet valve member covers the inlet port, the inlet valve member including an outer support and an inner seal sized to seal the inlet port during a dispensing stroke of the piston. Two or more connecting feet connect the outer support to the inner seal for quickly closing the inlet port during a dispensing stroke of the piston. At least one of the connecting legs comprises a circumferential portion extending circumferentially around the seal to provide a larger communication port for the viscous fluid between the legs during the suction stroke of the piston.

Another aspect relates to a dispensing pump valve that includes a valve opening and a valve member. The valve member includes an outer support disposed about the valve opening and an inner seal sized to seal the valve opening. Two or more connecting feet connect the outer support to the inner seal. At least one of the connection legs includes a portion that extends circumferentially around the inner seal.

Another aspect relates to a dispensing pump assembly that includes a pump mechanism that forms a pump chamber. The pump mechanism includes an inlet valve member for controlling the flow of fluid into the pump chamber, and a piston slidably received in the pump chamber for pumping fluid from the pump chamber. The piston defines a flow passage through which fluid may be pumped from the pump chamber. The pump head has a dispensing outlet fluidly connected to the flow passage for dispensing the fluid. An outlet valve member is received in the flow passage of the piston for controlling the flow of fluid out of the pump chamber. The flow passage includes a first portion sized to form a piston-type fit between the first portion and the outlet valve member to withdraw fluid from the dispensing outlet after the fluid has been dispensed. The second portion is larger in size than the first portion to allow fluid to flow around the outlet valve member during fluid dispensing.

Another aspect relates to techniques for priming a pump. Such pumps include an inlet valve that seals an inlet port of the pump. The inlet valve member includes an outer support, an inner seal sealing the inlet port, and at least two connecting legs connecting the outer support to the inner seal. The container is filled with the fluid through a top opening of the container. The pump is pre-filled by securing the pump over the top opening of the container so that the pressure of the fluid within the container opens the inlet valve member to at least partially fill the pump chamber with fluid.

Other forms, objects, features, aspects, benefits, advantages, and embodiments of the present invention will become apparent from the detailed description and drawings provided herein.

Drawings

FIG. 1 is a cross-sectional view of a fluid dispensing assembly according to one embodiment of the present invention.

Fig. 2 is a cross-sectional view of the assembly of fig. 1 during a dispensing stroke.

FIG. 3 is a front view of the pump body used in the assembly of FIG. 1.

FIG. 4 is a front cross-sectional view of the pump body shown in FIG. 3.

Fig. 5 is a top view of an inlet valve of the assembly of fig. 1.

Fig. 6 is a side cross-sectional view of the inlet valve shown in fig. 5.

FIG. 7 is a cross-sectional view of a pump cylinder for the assembly shown in FIG. 1.

Fig. 8 is a front view of the piston of the assembly of fig. 1.

Fig. 9 is a front cross-sectional view of the piston shown in fig. 8.

Fig. 10 is a bottom view of the plug of the assembly shown in fig. 1.

Figure 11 is a side cross-sectional view of the plug shown in figure 10.

Detailed Description

For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the illustrated embodiments, and any further applications of the principles of the invention as illustrated herein are contemplated as would normally occur to one skilled in the art to which the invention relates. One embodiment of the invention is shown in more detail herein; it will be apparent to those skilled in the relevant art, however, that some features that are not relevant to the present invention may not be shown for the sake of clarity.

An airless pump assembly 30 according to one embodiment of the present invention is shown in fig. 1 and 2. As shown, the pump assembly 30 includes a reservoir 32 for storing fluid, a slave piston 34 received in the reservoir 32, a pump 37 for pumping fluid from the reservoir 32, and a pump cap 39 covering the pump 37. Fig. 1 and 2 show two cross-sectional elevational views, with fig. 1 showing slave piston 34 at the bottom of container 32 with pump 37 at the top of its stroke, and fig. 2 showing slave piston 34 at a point where substantially all of the contents of container 32 have been dispensed with pump 37 at the bottom of its stroke. It should be noted that directional terms such as "upper," "lower," "top," "bottom," "left," and "right" are used merely for convenience of the reader to aid the reader in understanding the illustrated embodiments, and are in no way used to limit the illustrated features to a particular orientation. The pump assembly 30 will be described with reference to a driven piston type system, but it should be appreciated that selected features of the assembly 30 may be applicable to other types of pumping systems, such as airless dispensing pumps of the variable flat bag type.

Referring to FIG. 1, the slave piston 34 is slidably received in a cavity 43 within the reservoir 32, the slave piston 34 having upper and lower seals 44 that seal against the reservoir 32. An upwardly projecting ring or support 46 at the base 47 of the container 32 prevents the slave piston 34 from being pushed excessively into the base 47 of the container 32 during packaging, thereby reducing the risk of damage to the under-piston seal 44. When fluid is dispensed from the container 32, a slight vacuum is created and the slave piston 34 moves upwardly within the cavity 43 to reduce the effective size of the cavity 43. At the base 47, the container 32 has one or more vent slots 49 that allow venting of the container 32, as well as another opening (not shown), to prevent a vacuum from forming between the underside of the slave piston 34 and the base 47 of the container 32 as the slave piston 34 progressively moves upward during dispensing. The base 47 of the container 32 also has a drive dog 52 which allows the outside of the container 32 to be printed on. In the illustrated embodiment, the container 32, as well as other components, have a generally cylindrical shape, but it should be understood that in other embodiments these components may have different shapes.

In the pump assembly 30, the pump 37 is secured to the container 32 by a snap-fit type connection. It should be understood, however, that the pump 37 may be secured to the container 32 in other ways. As shown in fig. 1 and 2, the pump 37 includes a pump body 55 secured to the container 32, an inlet valve member 57 that controls the flow of fluid into the pump 37, a pump cylinder 60 in which a pump piston 61 is slidably disposed, an outlet valve member 64, a pump head 66 for dispensing fluid, a return spring 67, and a nozzle plug 68. Turning to fig. 3 and 4, the pump body 55 has one or more ridges 72 that snap fit into corresponding grooves in the container 32. The pump body 55 also has a pump cover groove 74 to which the pump cover 39 is fixed, and a fixing flange 75 provided between the ridge 72 and the pump cover groove 74. The pump body 55 defines an inlet port 77 at one end through which fluid from the container 32 may be received, as shown in FIG. 4. Around the inlet port 77, the pump body 55 has a sealing ridge or valve seat 80 that is biased against and seals with the inlet valve member 57, and around the sealing ridge 80, the pump body 55 also has a valve retention ridge 82 that aligns the inlet valve member 57 with the inlet port 77.

The inlet valve member 57 has a unique design that provides a number of advantages in dispensing viscous creams or other viscous fluids. As can be seen in fig. 5 and 6, the inlet valve member 57 has a generally planar, circular disc shape, but it should be understood that the inlet valve member 57 may have a different overall shape in other embodiments. The inlet valve member 57 includes an outer peripheral ring or support 85 and an inner seal 87 connected to the outer support 85 by two or more connecting legs 88. In the illustrated embodiment, the outer support 85 is in the form of a continuous ring, but it is contemplated that the outer support 85 can have a different overall shape. For example, the outer support 85 may comprise discontinuous segments in other embodiments. In the illustrated embodiment, the inlet valve member 57 has three legs, but in other embodiments the valve 57 may have two or even more than three legs. Each leg 88 includes an outer portion 90 that extends generally radially inwardly from the outer support 85 and an inner portion 91 that extends radially outwardly from the seal 87. Between the outer portion 90 and the inner portion 91, each leg 88 has a circumferential portion 92 that extends circumferentially between the support and the seal 87 such that the legs 88 extend generally around the periphery of the seal 87. As shown, the leg 88 is surrounded on both sides by flow openings 94. In the illustrated embodiment, the outer and inner portions 90, 91 of each leg 88 are radially offset equidistantly from one another, in this case about 120 degrees (120), such that the legs 88 are generally in the form of equal arcuate segments. In another embodiment in which two, rather than three, legs 88 are used, the legs 88 form an approximately 180 degree (180) arc, thereby allowing further elongation of the legs 88 for a given size of inlet valve member 57. The length and shape of the leg 88 ensures that the inner seal can be lifted from the valve seat 80 to form a series of large openings through the bore 94 that allow viscous fluid to easily flow into the pump 37. By having the legs 88 extend circumferentially or circumferentially, the legs 88 may be longer than if they were to extend only in a radial direction, and larger flow openings may be formed due to the longer legs 88. The design of the inlet valve 57 not only allows a large orifice to be formed for easy flow of viscous fluid, but also importantly allows the inlet valve member 57 to close in an extremely rapid manner. The seal 87 is able to seal quickly against the valve seat 80 by the two or more legs 88 pulling around the seal 87. The rate at which the seal 87 closes on the valve seat 80 can also be adjusted by varying the width, thickness and/or number of the legs 88, or by using a more or less rigid material. Thus, by merely replacing the inlet valve member 57 with an inlet valve member having a different characteristic, the pumping action of the pump 37 can be altered to accommodate fluids of different characteristics. For example, it has been found that the use of three feet 88 of the same size provides the desired size of the flow opening, as well as good shut-off performance.

In one embodiment, the inlet valve member 57 is made of plastic to avoid contamination of the product with metal. As mentioned above, it is desirable that the drug does not come into contact with the metal to avoid contamination. In one particular form, it has been found that the inlet valve member 57 works well when made from relatively inexpensive polyolefin materials (polyethylene/polypropylene family). It is contemplated, however, that the inlet valve member 57 may be made of other materials. For example, the inlet valve member 57 may also be made of more complex polymers in applications requiring operation under heat or where chemical compatibility is a concern. All of the remaining components of the assembly 30, except for the spring 67 and possibly the outlet valve member 64, may be made of a polyolefin material, which may reduce manufacturing costs. It should be understood, however, that in other embodiments, the components of the assembly 30 may be made of different materials, such as metal, if desired.

Referring back to fig. 1 and 2, when assembled in the pump 37, the inlet valve member 57 is sandwiched between the pump body 55 and the pump cylinder 60. The pump body 55 in fig. 4 has a connecting section 98 that extends around the inlet port 77 and the valve retention ridge 82. The connecting section 98 has one or more snap-in grooves 99 on the inside that can receive corresponding snap-in ridges 101 on a body-engaging flange 103 extending from the pump cylinder 60 as shown in fig. 7. At the end of the pump cylinder 60 facing the inlet valve member 57, a retaining ridge 105 on the pump cylinder 60 clamps onto the support 85 on the inlet valve member 57. This ensures that the inlet valve member 57 cannot be removed and remains in the correct relationship with respect to the inlet port 77 in the pump body 55 at all times. To ensure rapid priming, the seal 87 is biased to the closed position by the valve seat 80 around the inlet port 77 of the pump body 55 so that the inlet valve member 57 is substantially air-tight during initial priming of the pump 37. The amount of preload bias can be varied according to particular requirements. For example, the valve seat 80 in one embodiment extends a height of about 0.3 millimeters around the inlet port 77.

The pump cylinder 60 defines a pump chamber or pump chamber 108 in which the piston 61 is slidably received. Although pump cylinder 60 and pump chamber 108 in FIG. 7 are generally cylindrical in shape, it is contemplated that in other embodiments they may have a different overall shape, such as rectangular. A piston guide 110 with a guide bore 112 extends into pump chamber 108 of pump cylinder 60, and a guide flange 114 extends around guide opening 112. The piston guide 110 and the guide flange 114 together define a spring retaining groove 115 in which the spring 67 (fig. 1) may be received.

As shown in fig. 8 and 9, the piston 61 has a piston head 120 attached to a shaft or shank 122. The piston head 120 has upper and lower seals 124 that extend away from the piston head 120 in a very small angular fashion to seal against the walls of the pump chamber 108. The piston head 120 of the piston 61 and the shaft 122 together define a flow passage 127 through which fluid may be pumped. At the end of the shaft 122 opposite the piston head 120, the pump head 66 is snap-fit onto the shaft 122, as shown in fig. 1 and 2. It will be appreciated, however, that the pump head 66 may be connected to the shaft 122 in other manners. As shown, an outlet nozzle 129 with an outlet opening 130 in the pump head 66 is in fluid communication with the flow passage 127 in the shaft 122 so that fluid from the container 32 can be dispensed to a user. It should be noted that the spring 67 is mounted on the outside of the shaft 122 between the pump head 66 and the cylinder 60, and therefore, the spring 67 does not contact the dispensed product. As mentioned above, this is very important for drugs where it is critical that the drug does not come into contact with the metal.

The pump 37 in the illustrated embodiment is configured to reduce the amount of fluid remaining at the outlet opening 130 of the pump head 66 where the fluid dries or hardens from contact with air. To address this issue, the pump 37 incorporates a suck back feature, wherein fluid in the outlet opening 130 is sucked back into the pump 37. Referring to fig. 1 and 9, the piston 61 has a valve seat or flange 133 with a tapered surface 134 in the flow passage 127, the outlet valve member 64 sealing against the valve seat 133. The outlet valve member 64 functions like a check valve to allow fluid flow in only one direction. In the illustrated embodiment, the outlet valve member 64 has a generally spherical or ball shape, but it should be understood that the outlet valve member 64 may have a different shape in other embodiments. For example, the outlet valve member 64 may have a cylindrical shape in other embodiments. To reduce metal contact within the pump 37, the outlet valve member 64 is made of a non-metallic material in one embodiment. For example, the outlet valve member 64 is made of glass in one embodiment; however, in other embodiments, a wide variety of plastic materials may be used. In systems where metal contact is not a concern, it is contemplated that the outlet valve member 64 may be made of metal.

Downstream of the valve seat 133, the flow passage 127 has a first portion 136 that is only slightly larger than the diameter (size) of the outlet valve member 64 to allow movement of the outlet valve member 64 while preventing fluid from passing around the outlet valve member 64. This interference fit between the outlet valve member 64 and the first portion 136 of the flow passage 127 forms a piston-type fit that may be used to withdraw fluid from the outlet nozzle 129 during the upstroke of the piston 61. Near the pump head 66, the flow passage 127 has a second portion 138 that is larger than the first portion 136, and therefore the second portion 138 is sufficiently large in size to allow fluid to flow around the outlet valve member 64 during the downstroke of the piston 61. In the second portion 138, the piston 61 has a rib 140 that centers the outlet valve member 64 over the first portion 136 so that the outlet valve member 64 can drop back into the first portion, as shown in FIG. 2. The ribs 140 extend radially inward along the axis of the flow passage 127. Without the ribs 140 or other centering structure, the outlet valve member 64 would move to one side, which would delay its return to the valve seat 133 and, in the worst case, would cause air to be drawn back into the pump chamber 108. At one end of the flow passage 127, the pump head 66 has a stop 143 that limits the travel of the outlet valve member 64 between the valve seat 133 and the stop 143. It is contemplated that in other embodiments, the pump 37 may also incorporate a spring or other type of biasing device to bias the outlet valve member 64 against the valve seat 133. By incorporating this suck-back feature in the piston 61, the assembly of the piston mechanism is simplified.

The pump 37 in the illustrated embodiment is manually activated by pressing on the pump head 66, but it should be understood that the pump 37 in other embodiments may be automatically activated. Prior to use, the pump cap 39 and plug 68 are removed from the pump 37. After the pump head 66 is depressed, the spring 67 returns the piston 61 and thus the pump head 66 to the extended position. The outlet valve member 64 is moved from the second portion 138 (fig. 2) to the first portion 136 (fig. 1) of the flow passage 127 by this upstroke or intake stroke of the piston 61. Once the outlet valve member 64 reaches the first portion 136, the outlet valve member 64 slides tightly within the first portion 136 and acts like a true piston, drawing fluid from deep within the outlet nozzle 129 back into the flow passage 127 to a position above the outlet valve member 64. By drawing fluid from the nozzle 129, the likelihood of the fluid encrusting at the outlet opening 130 is reduced. During the upstroke, the outlet valve member 64 eventually seats against the valve seat 133, thereby creating a vacuum in the pump chamber 108, as shown in FIG. 1. The vacuum created in the pump chamber 108 causes the inlet valve member 57 to open, thereby providing a wider passageway for fluid from the container 32 to enter the pump chamber 108. During the downstroke or dispensing stroke of the pump 37, the inlet valve member 57 closes to prevent the fluid within the pump chamber 108 from being pushed back into the container 32. The outlet valve member 64 is lifted from the valve seat 133 to allow fluid to be dispensed through the outlet nozzle 129. Specifically, as the outlet valve member 64 travels within the first portion 136, fluid cannot pass around the outlet valve member 64, but once the outlet valve member 64 reaches the larger second portion 138 of the flow passage 127, fluid is able to exit the nozzle 129 around the outlet valve 64. Additional fluid may be dispensed by depressing and releasing the pump head 66 in the manner described above.

To ensure that the outlet 130 of the nozzle 129 remains clean during initial shipment, a nozzle plug 68 is inserted into the nozzle 129 to ensure that there is no fluid leakage. Turning to fig. 10 and 11, the plug 68 includes a handle or boss 147 for pulling the plug 68 out of the nozzle 129, and a plug portion 148 that is inserted into the outlet opening 130 of the nozzle 129. The plug portion 148 incorporates a small vent slot 150 that is sized small enough to prevent leakage of medium to high viscosity fluids, but to allow air to escape during initial priming of the pump 37. To also help reduce leakage during shipment, the pump 37 is covered by a pump cover 39. The pump cover 39 ensures that the pump head 66 is not inadvertently depressed during shipping and that the dispensing pump 37 remains in its original state and clean for display. The pump cover 39 also allows the entire package to withstand the high top loads that can occur when many packages are stacked one on top of the other.

Before filling the container 32, the slave piston 34 is preassembled in the container 32 and pushed to the bottom position, as shown in fig. 1. As described above, the support 46 in the container 32 prevents the driven piston 34 from being pushed excessively into the seat 47 of the container 32. The pump assembly 30 is designed to be "top-filled" in that the container 32 normally passes through a filling line and is filled from the top with the fluid or product first dispensed on top of the slave piston 34. In one form, an insertion nozzle that can be used to fill the container 32 is first inserted into the cavity 43 to a position just above the slave piston at the bottom of the container 32 and gradually retracted as the fluid is dispensed. This technique ensures that minimal air is entrained that would compromise the performance of the assembly 30. Once the appropriate fill level is reached, dispensing pump 37 is snap-fitted on top of container 32, along with plug 68 and pump cap 39. During the snap-fit of dispensing pump 37 onto container 32, the fluid within container 32 forces inlet valve member 57 open and partially fills pump chamber 108. The extremely fine vent groove 150 in the plug 68 ensures that entrained air under pressure can escape when the pump 37 is snapped into place, thereby ensuring that the opening of the inlet valve member 57 is unobstructed for filling. Venting via the vent slot 150 also reduces the risk of product spilling over the snap fit between the container 32 and the pump body 55. By priming the pump 37 in this manner, it is ensured that even the most viscous fluid requires the least amount of priming stroke to start operation of the pump 37.

While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character; it being understood that only the preferred embodiment has been shown and described and that all changes, equivalents, and modifications that come within the spirit of the invention as defined by the following claims are desired to be protected. All publications, patents and patent applications cited in this specification are herein incorporated by reference as if each individual publication, patent or patent application were specifically and individually indicated to be incorporated by reference and set forth in its entirety herein.

Claims (21)

1. An airless dispensing pump assembly comprising:

a pump mechanism forming a pump chamber with an inlet port through which a viscous fluid can be supplied from a container, the pump mechanism being sealed to the container and configured to reduce air infiltration into the container, the pump mechanism comprising

A piston slidably received in the pump chamber to pump fluid from the pump chamber,

an outlet valve member configured to permit viscous fluid to flow out of the pump chamber during a dispensing stroke of the piston and to create a vacuum in the pump chamber during an intake stroke of the piston, an

An inlet valve member covering the inlet port, the inlet valve member including,

the outer supporting piece is arranged on the outer side of the inner supporting piece,

an inner seal sized to seal the inlet port during a dispensing stroke of the piston, an

Two or more connecting legs connecting the outer support to the inner seal for rapidly closing the inlet port during a dispensing stroke of the piston, wherein at least one of the connecting legs comprises a circumferential portion extending circumferentially around the seal to provide a larger communication port for viscous fluid between the legs during an intake stroke of the piston.

2. The assembly of claim 1, further comprising:

the piston includes a shaft defining a flow passage; and

a metal spring surrounding the shaft outside the flow passage to reduce metal contamination of the viscous fluid.

3. The assembly of claim 2, wherein the piston, outlet valve member and inlet valve member are made of a non-metallic material.

4. The assembly of claim 1 wherein said piston defines a flow passage with a valve seat against which said outlet valve member seals during said intake stroke.

5. The assembly of claim 4,

the pump mechanism includes an outlet opening in fluid communication with the flow passage to dispense fluid from the flow passage;

the flow passage having a first portion disposed proximate to the valve seat and a second portion disposed distal to the valve seat;

said first portion being sized slightly larger than said outlet valve member to allow said outlet valve member to slide into said first portion while forming a piston-type fit between said first portion and outlet valve member to withdraw viscous fluid from said outlet opening during an intake stroke of said piston; and

the second portion is larger in size than the first portion to allow viscous fluid to flow around the outlet valve member and out the outlet opening during a dispensing stroke of the piston.

6. The assembly of claim 5, wherein the second portion includes a guide structure that guides the outlet valve member back into the first portion to reduce air infiltration into the pump chamber.

7. The assembly of claim 6, wherein the guide structure comprises one or more ribs.

8. The assembly of claim 5, wherein the pump mechanism includes a stop extending adjacent the second portion to limit movement of the outlet valve member.

9. The assembly of claim 1 wherein said outlet valve member is spherical.

10. The assembly of claim 1 wherein said inlet valve member is disc-shaped.

11. The assembly of claim 1, wherein the support is annular.

12. The assembly of claim 1,

the inlet valve piece comprises three connecting support legs;

each of the three connecting legs comprises a circumferential portion; and

the three connecting feet are equally spaced around the inner seal.

13. The assembly of claim 1, wherein the pump mechanism includes a sealing ridge disposed about the inlet port to preload the inlet valve.

14. The assembly of claim 1, wherein the pump mechanism comprises:

a pump body configured to be coupled to the container and defining the inlet port;

a pump cylinder defining the pump chamber; and

wherein the pump chamber and the pump cylinder are connected together with the inlet valve member sandwiched therebetween to secure the inlet valve member over the inlet port.

15. The assembly of claim 1, further comprising a container.

16. The assembly of claim 15, further comprising:

a slave piston slidably disposed in said container with at least one seal sealable on said container; and

the container has a base with a support that supports the slave piston during filling of the container to reduce damage to the seal.

17. The assembly of claim 1, further comprising:

the pump mechanism includes an outlet opening through which a viscous fluid can be dispensed; and

a plug received in the outlet opening to reduce viscous fluid leakage during shipping, wherein the plug comprises a vent groove sized to vent gas from the pump mechanism when the pump mechanism is connected to the container to allow priming of the pump mechanism.

18. A method of priming a pump, comprising:

providing a pump having an inlet valve member that seals an inlet port of the pump, wherein the inlet valve member includes an outer support, an inner seal that seals the inlet port, and at least two connecting feet that connect the outer support to the inner seal;

filling a container with a fluid through a top opening of the container, wherein the pump is sealed to the container and configured to reduce air infiltration into the container; and

the pump is filled by securing the pump over the top opening of the container such that fluid pressure within the container opens the inlet valve member to at least partially fill the pump chamber with fluid.

19. The method of claim 18, further comprising:

the container has a bottom with a support; and

before the filling, the driven piston is pushed to the bottom of the container and against the support.

20. The method of claim 19, wherein the filling comprises retracting an insertion nozzle for dispensing fluid from a bottom of the container to a top opening of the container in a progressive manner.

21. The method of claim 18, further comprising inserting a plug into an outlet opening of the pump mechanism, the plug having a vent slot that can vent from the pump chamber during the priming.