Manually actuated pump assembly

Information

  • Patent Grant
  • 6186368
  • Patent Number
    6,186,368
  • Date Filed
    Wednesday, May 26, 1999
    25 years ago
  • Date Issued
    Tuesday, February 13, 2001
    23 years ago
Abstract
A finger operated pump assembly comprising a pump body having a base supporting an outer housing and an inner housing and defining a first portion of a compression chamber therebetween. A piston is at least partially received within the pump body and is slidable relative to the pump body along an inner surface of the outer housing. The piston has an annular lip for providing a sealing engagement with the pump body, and the piston is provided with a piston outlet defined by a poppet valve seat. A poppet is accommodated by the inner housing and the poppet is biased away from the base into engagement with the poppet valve seat by a spring to normally close the piston outlet. The poppet, the base and the inner housing all define an interior cavity. A peripheral passageway communicates with the compression chamber, and the passageway includes a one-way valve which allows the product to flow along the passageway toward the compression chamber. The interior cavity is provided with a ventilation port which allows the interior cavity, during operation of the poppet, to operate at ambient pressure. The pump body is coupled to a turret which is connected to a closure.
Description




FIELD OF THE INVENTION




The invention relates to an improved manually operated pump assembly, categorized as an accumulative pump, for dispensing a product under high pressure. The pump assembly comprises a compression chamber for pressurization of the product to be dispensed and a relief valve operating, substantially at ambient atmosphere, for controlling the release of product through a piston outlet of the pump.




BACKGROUND OF THE INVENTION




A variety of prior art manually operated hand-held pump assemblies are well known and used for dispensing a variety of products such as liquids for personal care and pharmaceutical uses, fragrance products and the like. Pumps of this type comprise a housing body and a slidable piston which together define a compression chamber for receiving and dispensing of the product. The body, as well as the internal components contained within the body, are retained by a turret. An inlet in the base of the body communicates, via a dip tube, with the product to be dispensed. A conventional spray actuator communicates with an outlet of the piston to facilitate operation of the pump and provides a mechanical mechanism for dispensing the product, as desired, by an operator.




Directional flow of product to be dispensed, from the interoir of the container into the compression chamber of the body, is controlled by a first one-way valve, typically located at or adjacent to the coupling of the body inlet to the dip tube. A second one-way valve enables the product to be dispensed from the compression chamber through the piston outlet and into a supply passage of the actuator. Finally, the product is dispensed out through a discharge orifice of the actuator.




It is desirable for the pump to reach a specified pressure, prior to releasing the product to be dispensed from the compression chamber, to ensure that the product dispensed out the discharge orifice exhibits consistent and uniform spray characteristics. For example, some sprays need to consist of particles of uniform size, e.g. particles lying within a narrow particle size range, in order for proper dispensing of the product. It is also desirable to dispense a specific dosage of product during a single actuation of the actuator. To accomplish both the desired dosage and particle size requirements, the construction and function of the pump assembly require accurately designed internal components which must be precisely controlled during operation of the pump assembly. Because the body, the piston, the spring, the valve, etc., determine the configuration and operating pressure of the compression chamber, these components are very important in controlling the function of the pump assembly.




Product dispensing requirements are increasingly more demanding. With an increase in the use of low volatile solvents, as the main carrier component for the product to be dispensed, and as well as using more viscous gel-type liquids, the design requirements for dispensing such products are more critical. In particular, the low volatile solvents and the viscous gel-type liquids require higher discharge pressures, to facilitate proper dispensing thereof, versus products that include solvents which are readily converted into vapor upon discharge. In an attempt to overcome this problem and facilitate control of the resulting spray configuration, many prior art pump assemblies use a single spring to both actuate the piston and also bias a second one-way valve. This single spring forces the piston back into its initial static position, once the actuator has actuated the piston, and holds the second one-way valve closed until a desired operating pressure is reached.




Other prior art designs use a first spring for returning the piston and a second spring for biasing the second one-way valve independently of the piston. The intended advantage of the two spring arrangement is that the second one-way valve spring can be independently adjusted to facilitate opening of the piston valve at a desired operating pressure. In either case, the second one-way valve and the spring(s) are all contained within the compression chamber of the body and are subjected to the generated operating pressure within the compression chamber. The spring(s) (or other known conventional biasing members) are typically located to bias the second one-way valve against a piston valve seat. The amount of pressure required to compress the spring, and thus move the second one-way valve away from its associated valve seat, determines the operating pressure of the pump assembly. The construction of the spring thus determines the pressure at which the product is displaced from the body out through the discharge orifice. The spring pressure translates into a high reaction force upon the product as it is released by the second one-way valve and overcomes the spring bias.




It is to be appreciated that in order for the pump assembly to dispense liquid properly, the pump section of the assembly must be initially purged of any air contained within the compression chamber-this initial purging step is commonly referred to as “priming” of the pump. When the actuator is initially depressed by an operator, any air contained within the compression chamber of the body must be displaced in order for product to be siphoned into the compression chamber of the body via the dip tube. By depressing the actuator, the piston is moved toward a base of the body thereby compressing the spring as well as any air contained within the compression chamber. The compressed air assists with maintaining the first one-way valve in a closed position. The compressed air also induces an opening force on the second one-way valve but, in most cases, the induced force of the compressed air may never reach a high enough pressure to overcome the spring closing force of the second one-way valve. For this reason, prior art pumps use a small rib(s), or some other mechanical device located near the end of the compression stroke, to disrupt the seal between an inner part of the body and the piston and allow the compressed air to escape from the compression chamber. Two methods are used for allowing the compressed air to escape from the compression chamber. The first method is to allow the air to escape around the piston which can result in residual product drying along the escape path and seizing the piston. The second method is to allow air to escape down the dip tube which results in the air and the product to be dispensed reciprocating back and forth within the tube, which is also undesirable.




Because both the second one-way valve and the spring occupy space inside the body, these components effect the compression of the air during the priming operation of the pump, and thus effect the operation of the second one-way valve. This also means that the product, siphoned via the dip tube into the body, is then pushed back through the system in the reverse direction as the piston reciprocates. This to and for movement of the air and the product reduces the efficiency of the pump and increases the force needed to operate the system. In addition, the number of strokes required in order to remove the air contained within the compression chamber is increased.




SUMMARY OF THE INVENTION




Wherefore, it is an object of the present invention to overcome the aforementioned problems and drawbacks associated with the prior art pump assembly designs.




Another object of the present invention to design a pump assembly, utilizing a smaller number of components, which is efficiently primed and operated while still ensuring a high dispensing efficiency for the pump assembly.




A further object of the invention is to provide a movable poppet which operates at ambient pressure so that the function of the poppet is essentially unaffected by the flow or circulation of the product to be dispensed within the compression chamber.




Still another object of the invention is to increase the compression efficiency of the pump assembly and also minimize the number of strokes required to “prime” the pump assembly by providing a spring which is not located along or in communication with the product dispensing flow path so that the spring is not hindered by and does not hinder or interfere with the flow of the product to be dispensed.




Yet another object of the invention is to provide a simpler, lower cost, higher quality and efficient spray pump assembly that provides the same spray characteristics for low volatile solvents, water based products, alcohol base and/or other formulas.




A still further object of the invention is provide a pump assembly having a dispensing dosage of between about 120-250 ml of product, or so, an actuation force of between about 5.5-7.5 lbs., or so, and an internal operating pressure of the compression chamber of between about 100 to 170 psi, or so.




The manually actuated pump assembly, according to the present invention, is capable of dispensing a wide range of products. The highly efficient internal volume and priming system, according to the present invention, renders the manually actuated pump assembly ideal for use with personal care products, pharmaceuticals, fragrances, etc. A majority of the structural components of the manually actuated pump, according to the present invention, are located outside of the compression chamber thereby allowing minimal clearance between the inwardly facing surfaces defining the compression chamber when those surfaces are moved into the fully actuated position. Such design of the pump assembly aids in both priming and normal operation of the pump assembly.




Priming is accomplished by venting the trapped air either out through the discharge orifice or past a seal formed between the poppet and an inner cylindrical housing, rather than down the dip tube or around the compression piston. The prior art dispensing systems, that prime through the dip tube, experience difficulties when dispensing gels or high water content products or when utilizing a long length dip tube. As note above, the pump assemblies that prime around the compression piston have a tendency to become clogged or seized due to drying of the product residue.




During normal operation, according to the present invention, the pump assembly has a high operating pressure due to the ratio of the compression chamber diameter to the piston stroke length. With an operation pressure of approximately 130 psi or so, the manually actuated pump according to the present invention operates about 30% higher than conventional pumps currently available on the market today. Another advantage of the high compression design, of the present invention, is the uniform spray consistently achieved during each dispensing stroke. In addition, less variation in the internal volume results by locating the spring and valving components external of the compression chamber. Lastly, the improved profile of the components provides substantially unrestricted flow of the product from the compression chamber to the discharge orifice.




Finally, the present invention relates to a finger pump apparatus comprising a container for housing a desired product to be dispensed, said container being closed at one end and having a spout to facilitate dispensing of the product to be dispensed; a pump body having a base supporting an outer housing and an inner housing, and said outer housing and said inner housing at least partially defining a compression chamber therebetween; a closure supporting said pump body, and said closure sealingly engaging with the spout of the container; a piston being at least partially received within said pump body and being slidable relative to said pump body along said outer housing, said piston having an annular lip for providing a sealing engagement with the pump body, and said piston being provided with a poppet valve seat defining a piston outlet; an actuator being coupled to said piston outlet, and said actuator having a discharge outlet communicating with piston outlet for facilitating dispensing of a product; a poppet being accommodated by said inner housing, said poppet being biased away from said base of said pump body by a spring into engagement with said poppet valve seat to normally close said piston outlet and prevent flow of product therethrough, and said poppet, said base and said inner housing defining an interior cavity, and said interior cavity being provided with a ventilation port which allows said interior cavity, during operation of said poppet, to communicate with an interior of the container so that the interior cavity operates at ambient pressure; a passageway communicating with said compression chamber, said passageway including an inlet with a one-way valve which allows the product to flow along said passageway toward said compression chamber; and a dip tube coupling the inlet of the passageway to a base portion of said container to facilitate pumping of the product to be dispensed by the pump assembly.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a diagrammatic front perspective view of a container supporting the improved pump assembly according to the present invention;





FIG. 2

is a diagrammatic cross-sectional view of the improved pump assembly, according to the present invention, shown in a static position without an overcap, an actuator, a closure, a liner, or a dip tube affixed thereto;





FIG. 3

is a diagrammatic cross-sectional view of the improved pump assembly, according to the present invention, shown in the static position with an actuator, a closure, a liner and a dip tube attached thereto;





FIG. 4

is a diagrammatic cross-sectional view, of the improved pump assembly of

FIG. 3

, shown in a partially depressed position in which the poppet has been sufficiently displaced from the poppet annular seat to commence dispensing of product;





FIG. 5

is a diagrammatic cross-sectional view of the improved pump assembly of

FIG. 3

showing the fully depressed position of the pump assembly; and





FIG. 6

is a diagrammatic cross-sectional view, of the improved pump assembly of

FIG. 3

, shown in its partially returned position in which the poppet is biased against the poppet annular seat to facilitate suction of the product into the compression chamber during the return stroke of the improved pump assembly.











DESCRIPTION OF THE PREFERRED EMBODIMENT




While this invention is susceptible to various embodiments, the specification and the accompanying drawings disclose only one specific form as an example of the invention. For ease of description, the pump assembly embodying this invention is described in the normal operating position, in terms such as: upper, lower, horizontal, etc., are used with reference to this position. It will be understood, however, that the pumps and components embodying this invention may be manufactured, stored, transported, used, and sold in an orientation other than the position described.




Turning first to

FIG. 1

, a brief description concerning the improved pump assembly


10


, according to the present invention, used in combination with a prior art container


12


will now be provided. As can be seen in this Figure, the container


12


is a generally closed plastic container which has a spout (not shown in detail) formed on the top surface of the container. The spout is provided with an external thread (not shown) and has an aperture or opening formed therein to provide communication with an interior of the container


12


. The container


12


accommodates a desired quantity of liquid, fluid or some other product to be dispensed


14


. The product to be dispensed


14


is typically supplied from an interior space or area of the container


12


, via a dip tube


16


, to an inlet of the pump assembly


10


. As is well known in the art, the bottom end of the dip tube


16


is normally submerged in the liquid or product when the container is in a generally in an upright orientation, as illustrated in

FIG. 1. A

further detailed description concerning the function of the dip tube


16


will be provided below.




The pump assembly


10


is provided with removable cap or closure


18


which accommodates a depressible actuator


20


that is movable relative to the closure


18


to facilitate actuation of the pump assembly


10


, and a further detailed description concerning the purpose of such depression will follow below. If desired, a removable hood or overcap


22


, can encase or enclose the actuator


20


to prevent inadvertent actuation thereof. The overcap


22


is hollow shell member and typically has a perimeter edge that has a friction fit with a hollow annular skirt


24


extending from a top surface of the closure


18


. As such overcap feature in conventional and well known in the art, a further detailed description concerning the same is not provided.




With reference now to

FIGS. 2-6

, a detailed description concerning the improved pump assembly


10


, according to the present invention, will now be provided. As can be seen in

FIGS. 3-6

, for example, the base portion of the closure


18


is provided with an annular flange


26


which is located to abut against a mating flange surface (not shown in detail) of the container


12


. In addition, the closure


18


is provided with a central through bore


28


extending through the closure


18


along a longitudinal axis L of the improved pump assembly


10


. An inwardly facing surface


29


of the base of the closure


18


is provided with an internal thread


30


(or some other conventional retaining recess, lip or mechanism) for engagement with a mating external thread (or some other mating conventional retaining recess, lip or mechanism) provided on the spout of the container


12


. The closure


18


is also provided with a substantially centrally located, radially inwardly extending horizontal closure annular flange


32


which separates a base portion of the closure


18


from the annular skirt


24


. The annular flange


32


facilitates retention of the various components of the improved pump assembly


10


as will be discussed below in further detail.




A top surface of the actuator


20


is provided with a finger recess


34


which is preferably shaped or contoured to facilitate engagement with an index finger of an operator. As such shaping or contouring feature is well known in the art, a further description concerning the same is not provided. The actuator


20


is further provided with a downwardly extending annular side wall


36


which has a diameter that is slightly less than an inside diameter of the annular skirt


24


of the closure


18


to allow the annular side wall


36


of the actuator


20


to move relative to the annular skirt


24


, e.g. to move in and out of the space encompassed by the annular skirt


24


of the closure


18


without excess friction or contact occurring between those two components. According to a preferred embodiment of the invention, there is a relative sliding motion between an outwardly facing surface of the annular side wall


36


and an inwardly facing surface of the annular skirt


24


to facilitate guiding the actuator


20


as it is actuated or depressed toward the closure


18


. Such sliding motion facilitates maintaining the actuator


20


in its correct upright dispensing orientation.




An internal longitudinal central bore


38


is formed within the interior of the actuator


20


and the central bore


38


, in turn, communicates with a transverse radial bore


40


. The transverse radial bore


40


terminates at an opening formed in an exterior surface of the actuator which is sealed or closed by insert member


42


. The insert member


42


has a discharged orifice


44


formed therein. The discharged orifice


44


facilitates dispensing of the product to the dispensed


14


out of the actuator into the external environment. The insert member


42


is received within the transverse radial bore


40


and an outer periphery of the insert member


42


has a friction fit with an inner wall defining the transverse radial bore


40


to permanently retain the insert member


42


therein. An inwardly facing surface, located on the base of the insert member


42


, engages with an outwardly facing planar end surface of a central post


46


accommodated within the radial bore


40


. The end surface of the post


46


has a plurality of conventional inwardly directed channels


48


which lead to a conventional mixing chamber (not separately numbered) centrally formed on the end surface of the post


46


. It will be apparent to one skilled in the art that the plurality of inwardly directed channels


48


and the mixing chamber may also be located on and supported by the inwardly facing base surface of the insert member


42


, instead of the post


46


, for engagement with a substantially flat end surface of the post


46


. The mixing chamber directly communicates with the discharge orifice


44


for dispensing the throughly mixed and/or swirled product to be dispensed


14


out through the discharge orifice


44


. As this dispensing arrangement is conventional and well known in the art, a further detailed description concerning the same is not provided.




The annular flange


32


of the closure


18


mates with an annular flange


50


of a turret


52


(see

FIG. 3

for example) and also supports a gasket or liner


58


. The gasket or liner


58


is provided with a central aperture and is employed for biasing the annular flange


50


of the turret


52


against the annular flange


32


of the closure


18


, when the closure


18


is secured to the container


12


. The annular flange


32


of the closure


18


and the gasket or liner


58


sandwich the annular flange


50


of the turret


52


therebetween as the closure


18


is secured to the spout of the container. Such sandwiching arrangement is conventional and well known in the art.




An annular side wall


54


of the turret


52


extends through a central aperture, provided in the annular flange


32


, and the annular side wall


54


extends substantially parallel to the annular skirt


24


of the closure


18


and is spaced therefrom a sufficient distance to allow the annular side wall


36


of the actuator


20


to be readily received therebetween without an undue interference from the side wall


54


during operation of the actuator


20


. A top free end portion of the turret


52


is provided with an annular retaining edge


56


which first extends radially inwardly and then extends downwardly a short distance, along the longitudinal axis L, toward the base of the closure


18


. A further detailed description concerning the purpose of the retaining edge


56


will be provided below. An annular lip


59


(see

FIG. 2

) is provided on an inwardly facing surface of the annular side wall


54


of the turret


52


to facilitate retention of a pump body


60


and a further description concerning the purpose of the same will follow.




The pump body


60


, as can be seen in further detail with reference to

FIG. 2

, comprises an outer cylindrical housing


62


which is connected to a base


64


of the pump body


60


to form a single unitary component or structure. An inner cylindrical housing


66


is integrally connected to the base


64


, of the pump body


60


, and the inner cylindrical housing


66


is located concentric with the outer cylindrical housing


62


but spaced therefrom. An exterior surface of the pump body


60


supports an annular nub


69


which is located to engage with the annular lip


59


of the turret


52


and secure the pump body


60


to the turret


52


. A lower portion of the pump body


60


is provided with a cylindrical extension


70


having an inlet aperture


72


formed in a base end surface thereof. A first end of the dip tube


16


is frictionally received and retained within the inlet aperture


72


, as is conventionally done in this art.




The inlet aperture


72


communicates with a first portion of a compression chamber


68


, formed between an exterior surface of the inner cylindrical housing


66


and an inwardly facing surface of the outer cylindrical housing


62


, via a longitudinal passageway


74


. The longitudinal passageway


74


extends parallel to but is spaced radially from the longitudinal axis L of the pump assembly. A one way valve is located along the longitudinal passageway


74


and the one-way valve comprises a metal ball


76


that is captively retained within a cage


78


. The cage


78


allows limited to and for movement of the ball


76


to facilitate opening and closing of the one-way valve. This one-way valve allows the product to flow along the longitudinal passageway


74


when the ball


76


is spaced from an annular ball seat


80


(see FIG.


6


). The ball


76


normally rests, as can be seen in

FIGS. 3-5

, against the annular ball seat


80


to shut off product flow through the longitudinal passageway


74


. Prior to inserting the dip tube


16


within the inlet aperture


72


, the metal ball


76


is forced into the inlet aperture


72


, and urged past the annular ball seat


80


into the cage


78


where the ball


76


is thereafter permanently retained and utilized to operate the one-way valve.




It is to be appreciated that the ball


76


is normally held by gravity in a sealing position over the opening defined by the annular ball seat


80


so as to prevent the compressed liquid from being forced back down into the dip tube


16


. During actuation of the actuator, i.e. either during priming of the pump or dispensing of product, the generated pressure within the compression chamber additional serves to hold the ball


76


in its sealing engagement against the annular ball seat


80


. A further detailed description concerning the purposed of the same will follow below.




A piston


82


is at least partially accommodated within the body


60


and the piston


82


is slidably movable relative to the body


60


. A first lower end


84


of the piston


82


is provided with an annular sealing lip


86


, having an outer circumference slightly larger than the inner dimension of the outer housing


62


to provide a tight sealing engagement between the annular sealing lip


86


and the inner surface of the outer housing


62


. During operation of the piston


82


, as will be described below in further detail, the pressure generated within the compression chamber


86


assists with forcing the annular sealing lip


86


of the piston


82


into sealing engagement with the inwardly facing surface of the outer cylindrical housing


62


. An exterior surface of the piston


82


, adjacent the annular sealing lip


86


, is provided with an annular shoulder


88


which abuts against the annular retaining edge


56


of the turret


52


to captively retain at least the first lower end


84


of the piston


82


within the pump body


60


.




The piston


82


is a generally hollow member which has an exterior side wall that may taper slightly from the first lower end


84


to a second remote end


90


. A piston outlet


92


is formed adjacent the second remote end


90


of the piston


82


. The second remote end


90


of the piston


82


, located adjacent the piston outlet


92


, is provided with a reduced diameter annular cylindrical side wall


94


which is sized to be frictionally received within the central bore


38


of the actuator


20


and provide a secure retaining engagement between the second remote end


90


of the piston


82


and the actuator


20


. An annular surface of the piston


82


, defining the piston outlet


92


, forms the poppet valve seat


96


. The piston outlet


92


is normally closed by a shoulder


106


of an elongate generally cylindrical poppet


98


which is biased against the poppet valve seat


96


via a spring


104


. When the cylindrical poppet


98


becomes spaced from the poppet valve seat


96


, during actuation of the pump assembly, the piston outlet


92


is opened and allows the product to be dispensed


14


to flow from the compression chamber


68


to the central bore


38


of the actuator


20


, and a further detailed description concerning the same will be provided below.




As stated above, a first portion of the compression chamber


68


is formed between the inner cylindrical housing


66


and the outer cylindrical housing


62


. A remaining second portion of the compression chamber


68


is formed between an inwardly facing surface of the piston


82


and an exterior surface of the poppet


98


. The hollow interior dimension of the piston


82


is slightly larger than the outer diameter of the inner cylindrical housing


66


and either the piston


82


and/or the inner cylindrical housing


66


may have a channel(s) formed thereon so that the first portion of the compression chamber


68


is in constant communication with the remainder of the compression chamber


68


regardless of the position of the piston


82


relative to the inner cylindrical housing


66


.




The cylindrical poppet


98


is accommodated within a central cavity


100


defined by the inner cylindrical housing


66


. The poppet


98


is a solid elongate generally cylindrical member which supports an annular sealing and guide surface


102


adjacent a first lower end thereof. The annular sealing and guide surface


102


is sized to have an slight interference sliding fit with the inwardly facing surface of the inner cylindrical housing


66


. The annular sealing and guide surface


102


slides along the inwardly facing surface of the inner cylindrical housing


66


, in a sealed manner during operation of the pump assembly, and maintains the poppet


98


aligned with respect to the longitudinal axis L of the pump assembly


10


. The poppet


98


is biased into a normally closed position, via a spring


104


accommodated within an interior central cavity


100


, so that the shoulder


106


of the poppet


98


abuts against the poppet valve seat


96


, formed on the piston


82


, to shut off flow through the piston outlet


92


. As can be seen in

FIG. 2

, for example, the poppet


98


has a tapered or smaller constant diameter appendage


108


that extends through the piston outlet


92


and facilitates maintaining proper alignment of the poppet


98


with respect to the outlet


92


during operation of the pump assembly.




The base


64


of the central cavity


100


, accommodating the spring


104


, is provided with a ventilation port


110


which provides communication between the interior cavity


100


and an interior space of the container


12


to ventilate the cavity so that the central cavity


100


is at ambient pressure. The ventilation port


110


prevents the creation of either excess pressure or vacuum in the central cavity


100


during operation of the pump assembly


10


. A lower most portion of the poppet


98


, opposite the appendage


108


, is provided with a cylindrical extension


112


which receives one end of the spring


104


and further facilitates proper alignment and engagement between the poppet


98


and the spring


104


.




In a preferred form of the invention, a lower inwardly facing surface of the inner cylindrical housing


66


is provided with at least one nub or some other protrusion


114


so that when the annular sealing guiding surface


102


of the poppet


98


engages with the nub or other protrusion


114


, the remaining pressure in the compression chamber


68


is relieved and flows downward through the central cavity


100


and out through the ventilation port


110


, provided in the base


64


, into the interior space of the container


12


. It is to be appreciated that the nub or other protrusion


114


is formed on an inwardly facing surface of the inner cylindrical housing


66


at a location near the end of the stroke of the poppet


98


, e.g. after the poppet has moved about 95% to 98% of is normal operating stroke within the inner cylindrical housing


66


, so as not to compromise significantly the pumping efficiency of the compression chamber


68


.




The use of the protrusion or nub


114


is very useful in “priming” the air normally contained within the compression chamber


68


of the pump assembly following the manufacturing process. Since air is a compressible fluid, the compressed air typically may not generate, even after the full compression stroke of the actuator


20


, a sufficient pressure to bias the poppet shoulder


106


away from the poppet valve seat


96


and thereby allow discharge of the compressed air out of the compression chamber


68


into the central bore


38


of the actuator


20


. According to the present invention, if the actuator


20


is substantially completely depressed and the poppet shoulder


106


still has not been biased away from the poppet valve seat


96


to thereby open the piston outlet


92


, the air is immediately released by the breach in the seal formed between the annular sealing and guide surface


102


and the inwardly facing surface of the inner cylindrical housing


66


, once the annular sealing and guide surface


102


engages with the nub or the protrusion


114


. This released air is conveyed through the central cavity


100


and out the ventilation port


110


. On the return stroke of the actuator


20


, however, as soon as the annular sealing and guide surface


102


clears the nub or the protrusion


114


and again establishes a seal with the inner cylindrical housing


66


, a siphoning action is created within the compression chamber


68


and a quantity of the product to be dispensed


14


is siphoned, via the dip tube


16


and passageway


74


, toward the compression chamber


68


. This siphoned product will eventually flow into the compression chamber


68


where the product, which is generally an incompressible fluid, will actuate the poppet


98


in its intended dispensing manner after a sufficient number, e.g. four (4), of priming strokes.




It is to be appreciated that if replacement air is not allowed to enter inside the container


12


and replace the volume of dispensed product


14


, during normal operation of the pump, the container


12


will progressively become evacuated and eventually deform inwardly and/or collapse once a substantial portion of the product to be dispensed is sprayed. To alleviate this problem, at least one groove


116


is provided along either an exterior surface of the body


60


or an inwardly facing surface of the turret


52


. This groove


116


is normally sealed off from the external environment by the piston shoulder


88


engaging with the annular retaining edge


56


to provide a seal therebetween. Once the piston


82


is sufficiently depressed, the exterior surface of the piston


82


is slightly spaced from the annular retaining edge


56


to allow ambient air to flow along the exterior surface of the piston


82


and around the retaining edge


56


and down along the groove


116


, located between the exterior surface of the body


60


and the inwardly facing surface of the turret


52


, to replace the volume of the product which was just dispensed by the actuator


20


. This ventilation groove


116


also maintains the pressure inside the container at substantially the same pressure as the external surrounding environment.




Now that a detailed description concerning the basic components of the pump assembly, according to the present invention, were provided, a detailed description concerning actuation of the pump assembly will now be described.




Initially the pump assembly


10


is first installed on a spout of a desired container


12


, containing a product to be dispensed


14


, by engaging the threads


30


of the closure


18


with a mating thread, or some other conventional retaining mechanism, provided on an exterior surface of the spout of the container


12


. Once this has occurred, the dip tube


16


of the pump assembly is submerged within the product to be dispensed


14


such that an inlet of the dip tube is located adjacent a base of the container


12


. The pump assembly


10


is now ready for actuation.




When actuation is desired, the operator places his or her index finger on the finger recess


34


and depresses the actuator


20


, in the direction of arrow A of

FIG. 3

, so as to bias the actuator


20


downwardly along the longitudinal axis L toward the closure


18


. Such depression of the actuator


20


, in turn, causes a depression of the piston


82


which results in the annular sealing lip


86


sliding along the inwardly facing surface of the outer cylindrical housing


62


in an sealed manner toward the base


64


of the body


60


. This action causes the product to be dispensed


14


, contained within the compression chamber


68


, to come under pressure, i.e. it is to be noted that a liquid is generally incompressible. As the pressure of the product to be dispensed increases, this increase in pressure serves to bias the ball


76


against the annular ball seat


80


and thereby prevent the escape of any product downwardly back along the dip tube


16


. As noted above, the inwardly facing surface of the piston


82


is spaced a sufficient distance away from the outwardly facing surface of the inner cylindrical housing


66


to allow the product to be dispensed


14


to continuously flow therebetween regardless of the position of the piston


82


. Once the pressure within the compression chamber


68


increases to a sufficient pressure, e.g. an operating pressure of about 130 psi, the generated pressure of the product to be dispensed


14


overcomes the biasing force of the spring


104


and forces the poppet


98


downwardly toward the base


64


of the interior cavity


100


against the action of the spring


104


. This movement results in a compression of the spring


104


which allows the poppet shoulder


106


to separate away from the poppet valve seat


96


and thereby establishes a product flow path through the piston outlet


92


, as can be seen in FIG.


4


.




Once the poppet shoulder


106


is sufficiently spaced from the poppet valve seat


96


, the product to be dispensed


14


rushes through the piston outlet


92


and flows upwardly through the central bore


38


, the radially bore


40


, the inwardly directed channels


48


and is dispensed out through the discharge orifice


44


in a manner which generates a substantially uniform discharge spray configuration from the actuator


20


. The piston


82


continues to force the product to be dispensed


14


out through the actuator


20


, during further downward motion of the actuator in the direction of arrow A, until the annular lip


86


of the piston


82


abuts against the base


64


of the body


60


, as seen in FIG.


5


. Once the pump assembly is in its fully depressed position, an inwardly facing surface of the base


64


of pump body


60


is contoured to closely accommodate and substantially mirror the inwardly facing surface or profile of the annular sealing lip


86


of the piston


82


and thereby minimize the amount of the product to be dispensed


14


still remaining in the compression chamber


68


, e.g. the volume of the compression chamber is minimized by this arrangement. As is apparent from

FIG. 5

, the volume of the compression chamber


68


has been significantly reduced so that a substantial portion of the product to be dispensed


14


, that was previously stored within the compression chamber


68


, has been dispensed by the actuation stroke of the actuator


20


.




It is to be appreciated when the annular sealing and guide surface


102


, seen in

FIG. 5

, engages with the nub or the protrusion


114


, formed near a lower portion of the inner cylindrical housing


66


, the seal therebetween is breached and most of the remaining product to be dispensed, or air during initial priming of the pump assembly, is conveyed through the interior cavity


100


and out the ventilation port


110


to quickly relieve the generated pressure of the compression chamber


68


.




Once the actuation stroke is completed, the finger actuation pressure of the operator is relieved, e.g. the finger of the operator is removed from the finger recess


34


. Thereafter, the spring


104


immediately biases the poppet


98


, in the direction of arrow B of

FIG. 6

, toward and against the poppet valve seat


96


of the piston


82


to quickly close the piston outlet


92


and thereby prevent the further flow of the product to be dispensed


14


therethrough. The spring


104


also biases, due to biasing of the poppet


98


in the direction of arrow B, the piston


82


and the actuator


20


in an upward direction away from the closure


18


. During this return stroke of the pump assembly


10


, additional product to be dispensed


14


is siphoned into the inlet formed in the second end of the dip tube


16


. The siphoned product to be dispensed


14


flows along the dip tube


16


and moves or displaces the ball


76


away from the ball seat


80


to allow passage of the product to be dispensed


14


therepast along the longitudinal passageway


74


.




It is to be appreciated that the cage


78


captively retains the ball


76


, e.g. opens this one-way valve but retains the ball


76


so that the ball


76


may fall, due to the effects of gravity, back on the ball valve seat


80


following completion of the pump assembly return stroke to close this one-way valve. The product to be dispensed


14


continues to flow along longitudinal passageway


74


into the compression chamber


68


where the product to be dispensed


14


is accumulated and stored, as can be seen in FIG.


3


. Once the spring


104


has biased the poppet


98


, in the direction of arrow B, a sufficient distance such that the shoulder


88


of the piston


82


abuts against the annular retaining edge


56


, the ball


76


is again allowed to settle on ball valve seat


80


to thereby prevent further flow and allow pressurization of the compression chamber


68


when the actuator


20


is again depressed.




According to a preferred form of the invention, the compression chamber which has a maximum transverse dimension or diameter of between 0.225 and 0.275 inches, and more preferably a diameter of about 0.250 inches and the piston has a stroke length of between 0.275 and about 0.325 inches, and more preferably a piston stroke length of about 0.300 inches. This results in a compression chamber diameter to piston stroke ratio of between about 4 to 5 and about 2 to 3 which facilitates achievement of an operating pressure of approximately 130 psi or so.




According to the design of the present invention, if, during depression of the actuator


20


toward the closure


18


, the finger actuation pressure discontinues for any reason, once flow has been established through the piston outlet


92


, the spring


104


will immediately bias the poppet


98


in the direction of arrow B of the

FIG. 6

, toward and against the poppet valve seat


96


. This biasing action quickly closes the piston outlet


92


and thereby prevents the further flow of product to be dispensed


14


therethrough.




According to the present invention, passageway


74


leading to the compression chamber


68


extends along a second longitudinal axis LP which is off set with respect to the longitudinal axis L of the pump assembly but extends substantially parallel thereto. This arrangement facilitates venting of the base


64


of the central cavity


100


to the interior space of the container


12


so that the central cavity


100


operates at ambient pressure or to some other pressure other than the operating pressure of the compression chamber.




Since certain changes may be made in the above described finger operated pump assembly, without departing from the spirit and scope of the invention herein involved, it is intended that all of the subject matter of the above description or shown in the accompanying drawings shall be interpreted merely as examples illustrating the inventive concept herein and shall not be construed as limiting the invention.



Claims
  • 1. A finger pump assembly comprising:a pump body having a base supporting an outer housing and an inner housing, said outer housing and said inner housing being coaxial with one another and said outer housing and said inner housing at least partially defining a compression chamber therebetween; a closure supporting said pump body, and said closure having a mechanism for facilitating engagement with a spout of a container; a piston being at least partially received within said pump body and being slidable relative to said pump body between the coaxial outer and inner housings and along said outer housing, said piston having an annular lip for providing a sealing engagement with the pump body, and said piston being provided with a poppet valve seat defining a piston outlet; an actuator being coupled to said piston outlet, and said actuator having a discharge outlet communicating with said piston outlet for facilitating dispensing of a product; a poppet being at least partially accommodated by the inner housing, said poppet being biased away from said base of said pump body by a spring into engagement with said poppet valve seat to normally close said piston outlet and prevent flow of product therethrough, and said poppet, said base and said inner housing defining an interior cavity, and said interior cavity being provided with a ventilation port which allows said interior cavity, during operation of said poppet, to operate at ambient pressure; and a passageway communicating directly with said compression chamber, said passageway having an inlet and a one-way valve which allows the product to flow along said passageway and directly into said compression chamber without passing through the interior cavity.
  • 2. The finger pump assembly according to claim 1, wherein said poppet has an annular sealing and guide surface to facilitate sliding sealing engagement of the poppet along an inwardly facing surface of said inner housing.
  • 3. The finger pump assembly according to claim 1, wherein said poppet is provided with a poppet shoulder for engaging with said poppet valve seat which defines the piston outlet, and said poppet has an appendage which extends through said piston outlet to facilitate alignment of said poppet with said piston outlet.
  • 4. The finger pump assembly according to claim 1, wherein an end of said poppet, received within said inner housing, supports an extension which engages with a first end of said spring to facilitate orientation of said poppet along a longitudinal axis of said finger pump assembly.
  • 5. The finger pump assembly according to claim 1, wherein said pump body is coupled to a turret and said turret is connected to said closure, and a remote free end of said closure supports an annular skirt which extends away from a base portion of said closure.
  • 6. The finger pump assembly according to claim 5, wherein said turret has an annular sidewall and a free end portion of said annular sidewall is provided with an annular retaining edge for securely connecting said pump body to said turret.
  • 7. The finger pump assembly according to claim 5, wherein said actuator is provided with an annular sidewall which engages with said annular skirt of said closure to facilitate actuation of said actuator along a longitudinal axis of said pump assembly.
  • 8. The finger pump assembly according to claim 5, wherein said closure is provided with an annular flange, and said turret is provided with a mating annular flange, and said annular flange of said closure and a gasket sandwich said annular flange of said turret therebetween to facilitate a sealing engagement of said finger pump assembly with a desired container.
  • 9. The finger pump assembly according to claim 1, wherein said actuator has a central bore which communicates with said discharge orifice, and said piston has an annular housing side wall which frictionally engages with said central bore of said actuator to couple said piston to said actuator and facilitate the supply of the product to be dispensed from said piston to said discharge orifice.
  • 10. The finger pump assembly according to claim 1, wherein an inwardly facing surface of said inner housing is provided with at least one nub to facilitate relieving the pressure generated within the compression chamber once the poppet has been substantially completely displaced along an inwardly facing surface of said inner housing, and the relieved pressure is vented through the interior cavity and out through the ventilation port provided in the base of the pump body.
  • 11. The finger pump assembly according to claim 5, wherein at least one groove is provided between an exterior surface of said pump body and an inwardly facing surface of said turret to allow an equalization in pressure, once the finger pump assembly is connected to a container and operated, to prevent the container attached to the finger pump assembly from becoming at least partially evacuated.
  • 12. The finger pump assembly according to claim 1, wherein the passageway, communicating with said compression chamber, extends substantially parallel to a longitudinal axis of the pump assembly but is radially spaced from the longitudinal axis.
  • 13. The finger pump assembly according to claim 12, wherein the valve is located along said passageway communicating with said compression chamber, and said valve comprises a ball captively retained within a cage with said ball normally resting upon a ball valve seat to prevent flow of product along said passageway and, during a siphoning action of said pump assembly, said ball is displaced from said valve seat to allow the flow of product therethrough.
  • 14. The finger pump assembly according to claim 12, wherein a dip tube is coupled the inlet of the passageway to facilitate siphoning of the product to be dispensed from a base portion of a container.
  • 15. A finger pump apparatus comprising:a container for housing a desired product to be dispensed, said container being closed at one end and having a spout to facilitate dispensing of the product to be dispensed; a pump body having a base supporting an outer housing and an inner housing, said outer housing and said inner housing being coaxial with one another and said outer housing and said inner housing at least partially defining a compression chamber therebetween; a closure supporting said pump body, and said closure sealingly engaging with the spout of the container; a piston being at least partially received within said pump body and being slidable relative to said pump body between the coaxial outer and inner housings and along said outer housing, said piston having an annular lip for providing a sealing engagement with the pump body, and said piston being provided with a poppet valve seat defining a piston outlet; an actuator being coupled to said piston outlet, and said actuator having a discharge outlet communicating with said piston outlet for facilitating dispensing of a product; a poppet being at least partially accommodated by said inner housing, said poppet being biased away from said base of said pump body by a spring into engagement with said poppet valve seat to normally close said piston outlet and prevent flow of product therethrough, and said poppet, said base and said inner housing defining an interior cavity, and said interior cavity being provided with a ventilation port which allows said interior cavity, during operation of said poppet, to communicate with an interior of the container so that the interior cavity operates at ambient pressure; a passageway communicating directly with said compression chamber, said passageway having an inlet and a one-way valve which allows the product to flow along said passageway and directly into said compression chamber without gassing through the interior cavity; and a dip tube coupling the inlet of the passageway to a base portion of said container to facilitate siphoning of the product to be dispensed by the pump assembly from an interior of the container.
  • 16. The finger pump apparatus according to claim 15, wherein said poppet has an annular sealing and guide surface to facilitate sliding sealing engagement of the poppet along an inwardly facing surface of said inner housing;said poppet is provided with a poppet shoulder for engaging with said poppet valve seat which defines the piston outlet, and said poppet has an appendage which extends through said piston outlet to facilitate alignment of said poppet with said piston outlet; and an end of said poppet, received within said inner housing, supports an extension which engages with a first end of said spring to facilitate orientation of said poppet along a longitudinal axis of said finger pump assembly.
  • 17. The finger pump apparatus according to claim 15, wherein said pump body is coupled to a turret and said turret is connected to said closure, and a remote free end of said closure supports an annular skirt which extends away from said base portion of said closure;said turret has an annular sidewall and a free end portion of said annular sidewall is provided with an annular retaining edge for securely connecting said pump body to said turret; and said actuator is provided with an annular sidewall which engages with said annular skirt of said closure to facilitate actuation of said actuator.
  • 18. The finger pump apparatus according to claim 15, wherein said actuator has a central bore which communicates with said discharge orifice, and said piston has an annular housing side wall which frictionally engages with said central bore of said actuator to couple said piston to said actuator and facilitate the supply of the product to be dispensed from said piston to said discharge orifice.
  • 19. The finger pump apparatus according to claim 15, wherein the passageway, communicating with said compression chamber, extends substantially parallel to a longitudinal axis of the pump assembly but is radially spaced from the longitudinal axis.
  • 20. The finger pump apparatus according to claim 15, wherein at least one groove is provided between an exterior surface of said pump body and an inwardly facing surface of said turret to allow an equalization in pressure and prevent said container from becoming at least partially evacuated during operation of said finger pump apparatus.
  • 21. A single spring finger pump assembly comprising:a pump body defining a longitudinal axis and having a base supporting an outer housing and an inner housing, said outer housing and said inner housing being coaxial with one another and with the longitudinal axis and said outer housing and said inner housing at least partially defining a compression chamber therebetween; a closure supporting said pump body, and said closure having a mechanism for facilitating engagement with a spout of a container; a piston being at least partially received within said pump body and being slidable relative to said pump body between the coaxial outer and inner housings and along said outer housing, said piston having an annular lip for providing a sealing engagement with the pump body, and said piston being provided with a poppet valve seat defining a piston outlet; an actuator being coupled to said piston outlet, and said actuator having a discharge outlet communicating with said piston outlet for facilitating dispensing of a product; a poppet being at least partially accommodated by the inner housing, said poppet being biased away from said base of said pump body by a spring into engagement with said poppet valve seat to normally close said piston outlet and prevent flow of product therethrough, and said poppet, said base and said inner housing defining an interior cavity, and said interior cavity being provided with a ventilation port which allows said interior cavity, during operation of said poppet, to operate constantly at ambient pressure; and a passageway communicating directly with said compression chamber, said passageway having an inlet and a one-way valve which allows the product to flow along said passageway and directly into said compression chamber without passing through the interior cavity, and the passageway extending parallel to the longitudinal axis but being offset from the longitudinal axis.
US Referenced Citations (12)
Number Name Date Kind
4051983 Anderson Oct 1977
4189064 O'Neill et al. Feb 1980
4986453 Lina et al. Jan 1991
5064105 Montaner Nov 1991
5176296 Lina et al. Jan 1993
5579958 Su Dec 1996
5626264 Florez et al. May 1997
5641097 Renault et al. Jun 1997
5655688 Moore Aug 1997
5664706 Cater Sep 1997
5702031 Meshberg et al. Dec 1997
5894963 Hirota Apr 1999