HIGH VOLUME DISPENSING PUMP WITH SHORTENED AXIAL TRAVEL
20250025900 ยท 2025-01-23
Inventors
- Simon Christopher KNIGHT (Bridgend South Wales, IN)
- Gaurang MITTAL (Noida, IN)
- Prantik CHANDA (Noida, IN)
Cpc classification
B05B11/1077
PERFORMING OPERATIONS; TRANSPORTING
B05B11/1047
PERFORMING OPERATIONS; TRANSPORTING
International classification
B05B11/10
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A food and beverage reciprocating dispenser relies upon an external engine to shorten the axial travel and spring force required for actuation. This enables the delivery of more accurate and consistent dose volumes. The resulting pump has bore ratios that are improved by an order of magnitude in comparison to conventional designs.
Claims
1. A pump dispenser having an external pump engine including a pump chamber positioned above the radial sealing flange of an H-style closure cap, the dispenser comprising: a closure element including: (i) a cap having a radial flange defining an inlet bore and at least one air return vent, a lower skirt extending below the radial flange, and an upper skirt, (ii) a valve sealing the inlet bore, and (iii) a sleeve received within the upper skirt, the sleeve having at least one vent aperture and wherein return air pathways are provided between the sleeve and the upper skirt and communicate with the air return vent; an actuator including an outlet nozzle and a piston stem and wherein the piston stem has hollow tube communicating with the outlet nozzle through an outlet bore and an annular wiper configured to seal to and slide along an inner facing of the sleeve; and a biasing member positioned between the piston stem and radial flange and urging the actuator away from the closure element.
2. The pump dispenser of claim 1 further comprising a tether valve sealing the outlet bore.
3. The pump dispenser of claim 1 wherein the dispenser has a bore ratio greater than 3, greater than 5, greater than 10, or greater than 20 and wherein the bore ratio is less than 100, less than 80, less than 60, or less than or equal to 40.
4. The pump dispenser of claim 1 wherein the dispenser has a travel ratio greater than 0.60, greater than 0.80, greater than 1.0, greater than 1.5, or greater than or equal to 2.15 and wherein the dispenser has a travel ratio of less than 10.0, less than 5.0, less than or equal to 4.75, less than 3.0 or less than 2.50.
5. The pump dispenser of claim 1 wherein the piston stem and the biasing member are configured so that an axial travel distance during actuation and release of the dispenser is less than 50 mm, less than 40 mm, less than 30 mm, less than 20 mm, or less than or equal to 13 mm.
6. The pump dispenser of claim 1 wherein the piston stem includes a flexible spherical wiper.
7. The pump dispenser of claim 6 wherein the flexible spherical wiper is attached to a lower most end of the piston stem by a flexible U-shaped radial flange.
8. The pump dispenser of claim 6 wherein the flexible spherical wiper is attached to a mid-section portion of the piston stem by a flexible, curved radial flange.
9. The pump dispenser of claim 1 wherein the biasing member is made from an identical polymeric material as used in the closure element and the actuator.
Description
DESCRIPTION OF THE DRAWINGS
[0012] Operation of the invention may be better understood by reference to the detailed description taken in connection with the following illustrations. These appended drawings form part of this specification, and any information on/in the drawings is both literally encompassed (i.e., the actual stated values) and relatively encompassed (e.g., ratios for respective dimensions of parts). In the same manner, the relative positioning and relationship of the components as shown in these drawings, as well as their function, shape, dimensions, and appearance, may all further inform certain aspects of the invention as if fully rewritten herein. Unless otherwise stated, all dimensions in the drawings are with reference to inches, and any printed information on/in the drawings form part of this written disclosure.
[0013] In the drawings and attachments, all of which are incorporated as part of this disclosure:
[0014]
[0015]
[0016]
[0017]
[0018]
[0019]
[0020]
[0021]
[0022]
[0023]
[0024]
[0025]
[0026]
[0027]
DETAILED DESCRIPTION
[0028] Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. It is to be understood that other embodiments may be utilized and structural and functional changes may be made without departing from the respective scope of the invention. As such, the following description is presented by way of illustration only and should not limit in any way the various alternatives and modifications that may be made to the illustrated embodiments and still be within the spirit and scope of the invention.
[0029] As used herein, the words example and exemplary mean an instance, or illustration. The words example or exemplary do not indicate a key or preferred aspect or embodiment. The word or is intended to be inclusive rather an exclusive, unless context suggests otherwise. As an example, the phrase A employs B or C, includes any inclusive permutation (e.g., A employs B; A employs C; or A employs both B and C). As another matter, the articles a and an are generally intended to mean one or more unless context suggest otherwise.
[0030] In order to address the aforementioned needs and/or to overcome issues with conventional food and beverage dispensers noted above (e.g., minimizing the dose variation), the inventor realized one solution was to find a way of pushing the pump with greatly reduced force. The theory was if users are used to pushing a pump with higher force (i.e., >40 N), it should be possible to reduce this force by half and thereby incorporate a shorter stroke (more than half the customary length). In this manner, more reliable volumes/doses could be produced because the risk of the pump/actuator not being pushed completely down (i.e., all the way to the base) would be greatly reduced. Thus, one key to the inventive designs was to reduce the friction dramatically by, among other things, using a very light spring.
[0031] Conventional large dose pumps are deliberately designed with narrow diameters, so as to fit within the bottle/container neck. By relying on an external engine (i.e., one not disposed within the container or neck), it becomes possible to use wider and shorter pump chamber (and associated components, such as the piston/stem, valves, etc.), thereby reducing axial travel and spring force needed. This means the movement of the engine is now above the bottle neck, with the diameter of the fluid pathways (inlet size, outlet size, and pump chamber diameter) also increased. Normally, when more fluid is dispensed via a shorter stroke, the ETO increases. However, the inventive aspects contemplated herein enable a reduction of ETO by 50% even while reducing the stroke from 54 mm to 13 mm (almost a 4 reduction in axial travel).
[0032] The external pump design results in shorter stroke and increased the liquid bore that is 3.4 times larger, while the axial travel or stroke length is reduced by a factor of 3.8. The inventive design also easily achieves less than 5% variation in dose accuracy (depending on bottom valve solution) in comparison to 10% variation for convention designs. One particular example of a conventional pump has a bore ratio of 3.00 (167 mm2/54 mm stroke), whereas the inventive design has a bore ratio of 40.0 (572 mm2/14 mm stroke). Here, the bore ratio is based upon the surface area of the bore at the inlet and outlet, as defined by the minimum diameters or widths thereof (it being understood that the inlet and outlet could have a non-circular shape, provided appropriate adjustments were made to the necessary components).
[0033] Another means of expressing the comparative improvement is with respect to the ratio of the diameter of the closure to the length of axial travel, with conventional designs registering such a travel ratio of 0.52 (28 mm/54 mm) while the inventive pumps can range between 2.15 (28 mm/13 mm) and 4.75 (38 mm/8 mm).
[0034] The inventive design also relies upon a closure that imparts an improved aesthetic. Certain iterations also allow for the use of plastic springs in place of metal springs, thereby making the new design comparatively more sustainable and eco-friendly.
[0035] In particular, a bellows could be used as a substitute for a metal spring. Examples of such biasing members are disclosed in Patent Cooperation Treaty Publications WO 1994/020221A1 and WO 1996/028257A1, as well as U.S. Pat. Nos. 5,673,824; 5,819,990; and 5,924,603. Other proposed solutions for non-metallic springs can be found in Japanese Patent Publication 2005024100A; Patent Cooperation Treaty Publications WO2001/087494A1, WO2018/126397A1, and WO2020/156935A1; French Patent FR2969241B1; Korean Patent KR102174715B1; United States Patent Publications 2009/0102106A1, 2012/0325861A1, 2015/0090741A1, 2017/0157631A1, 2019/0368567A1, and 2020/0032870; and U.S. Pat. Nos. 5,819,990; 6,068,250; 6,113,082; 6,223,954; 6,983,924; 10,741,740; and 10,773,269. All of these disclosures are incorporated by reference.
[0036] Irrespective of the biasing member (all-plastic bellows, other plastic springs, or conventional metallic coiled springs), another notable feature in comparison to conventional food pumps is that the central portion of the biasing member need not be fitted around the piston or stem along its entire length. That is, whereas the prior art example provided a spring on the outer facing of the reciprocating stem, the inventive design merely captures the top and bottom portions. This provides for several advantages: 1) it simplifies the assembly of the pump by eliminating the need to coaxially and completely seat the biasing member over the elongated stem and 2) because the spring is positioned within the fluid pathway, it encourages the use of all-plastic members, which reduces the chances of metallic corrosion and promotes the use of a fully-recyclable design. Also, the shorter overall axial travel necessarily means that a shorter spring can be used (which was previously a detriment to the use of plastic springs in large volume dispensers-previously, the plastic springs could not easily accommodate the long axial travel lengths required by these large dose dispensers).
[0037] Further, the inventive aspects herein are easily adapted to the large-sized container necks used in the food and beverage industry, including but not limited to 28 mm and 38 mm. In a 38 mm sized closure, the dose volume could be as large as 8 mL, while only requiring 8 mm of axial travel. Still other arrangements are possible.
[0038] Turning to the drawings,
[0039] The pump generally consists of an actuator, a piston or push stem coupled to the actuator head, a biasing member, and a closure element. The closure element may be formed integrally or as a H-profile cap with a sleeve received in the upper portion of the cap. A coupling or snap-top collar/cover is fitted on the upper portion after the piston stem has been placed therein. Tethered flap valves (like the ones shown in
[0040] Bead-and-groove, slot-and-tab, or other coupling formations are provided at the interfaces of the actuator head and piston stem, within the closure elements individual components (and more specifically, at or near the top edges of the cap and the cover/collar), and anywhere else where a secure and possibly sealed fit is desired.
[0041] The sleeve conforms the contours of the cap but includes one or more vent apertures. These apertures are positioned within the upper portion of the cap at a level where wipers on the piston stem may seal the apertures (when the pump is fully extended) or expose/open the apertures. When open, return air may flow down through the piston stem and collar/cover, through the apertures, along the interface between the sleeve and an upright skirt defining the upper portion of the H-style cap, through vent apertures formed on the radial flange of the cap, and into the container.
[0042] The H-style cap has a general cross sectional shape approximating the letter H. The aforementioned top skirt is joined to a radial flange which defines the inlet bore and incorporates return air vents. A lower skirt extends below the flange, with its inner facing including threads or other features so that the cap can be attached to a container neck. An axial flange extending from the radial flange near the inlet bore defines a valve well. Channels or grooves may be formed on the collar/cap and the upper skirt to define the air pathway.
[0043] The valves comprise a circular blocking flap coaxially disposed within an annular sealing ring. The ring and flap are connected by one or more thinned tethers, which allow the flap to be temporarily displaced when exposed to suction created by the reciprocating action of the piston stem (and actuator) relative to the cap (and closuring element). These valves retain fluid in the pump chamber and prevent unwanted flowback, while also serving to protect the fluid from the ambient environment.
[0044] The piston stem includes a hollow bore of similar or greater diameter than the inlet bore. Similarly, the inner diameter of the pump chamber, whether defined by the inner facings of the sleeve or by the upper skirt, has a greater diameter than that of the piston stem. At its lower end, the piston stem includes wipers that seal to the inner facing of the pump chamber, thereby enabling suction to be created as the actuator urges the piston stem up and down. At its top end, the piston stem includes an outlet bore, preferably of similar dimensions to the inlet bore and sealed by a similar tethered flap valve (which is captured between the actuator head and the piston stem).
[0045] The inlet bore is configured to receive and support the lower extremity of a biasing member. The upper extremity is designed to couple or at least be retained by features on or near the hollow bore of the piston stem. These features may be interference fit, or they can simply be ribs or protrusions that cooperate with similar ribs or protrusions on the spring to restrain the spring and keep it positioned properly.
[0046] In operation, fluid is drawn up the hollow dip tube, past the inlet tether flap and into the pump chamber. Notably, because the pump chamber is not positioned within the container neck, its diameter is significantly larger than the dip tube. In turn, this increased diameter allows the pump chamber to accommodate larger volumes while retaining a shorter axial height in comparison to pump chambers on conventional food and beverage pumps.
[0047] The actuator head defines the final stages of the fluid pathway, with the outlet valve again providing sealing at the top edge of the pump chamber. The actuator may include a nozzle tip (like those shown in
[0048] Notably,
[0049] Blowby of this nature is problematic because the expected dose size will be reduced and, equally important, fluid will emanate from and accumulate on the exterior of the pump. When that fluid is perishable and/or prone to evaporate into a sticky residue, instances of blowby can be fatal to the utility of the pump itself (owing to inconsistent dosing, fluid loss, and potential soiling and/or spoilage of the fluid on the exterior surfaces of the pump).
[0050] In some instances, blowby can be addressed through judicious selection of materials. That is, by relying on sufficiently rigid and inflexible materials and wall thicknesses, the piston stem/wiper can be designed to not flex or deform. However, such design choices may not always be feasible to the extent thicker walls increase costs and rigid materials may not be preferred owing to manufacturing processes, sustainability, and/or cost considerations.
[0051] In such instances, the features of the piston stem can be altered as shown in
[0052] In this alternative arrangement, the elevation/location of the vent hole within the sleeve may be moved upward in comparison to its positioning in the embodiments of
[0053] Notably, this flexible spherical wiper can also be employed with the all-plastic biasing member design contemplated in
[0054] In all embodiments of the flexible spherical wiper, a stopper surface is provided, usually on the radial flange or arm that connects the wiper to the main body of the piston stem (either at its lower-most end, as seen in
[0055] A corresponding stopping surface, also forming part of the flexible spherical wiper structure also defines the lower most range of motion. In this instance, it may be the lower edge of the wiper, a skirt or crenelated extension positioned concentrically within the wiper (and offset radially inward enough to allow for the expected flexing action), or a combination of the two. Usually, this stopper will contact the sleeve or the closure.
[0056] Turning now to the drawings,
[0057] Notably, the vast majority, if not the entirety, of that pump chamber 6a is positioned coaxially within the diameter of closure 5. This arrangement requires that the maximum possible diameter or area 7a for fluid passing through the pump chamber 6a toward the outlet must be significantly smaller than the inner diameter of the closure 5, so as to receive the housing 6 and the lower portions of the stem 3. Because the dosing volume of the pump 1 is dictated by the volume of the pump chamber 6a, it becomes necessary to extend the axial length of the housing 6 and pump chamber 6a in order to increase dosing size. In turn, the actuation stroke needed to initiate pumping also becomes larger.
[0058] Additionally, conventional pumps of the prior art tend to have an even smaller maximum possible diameter or area 7b at their inlet because the spring 8 must be seated coaxially around the inlet. As a result, pumps 1 have a smaller inlet area 7b in comparison to the outlet area 7a. Also, the elongated housing 6 will occupy volume inside of the container that otherwise could have accommodated fluid for dispensing. It should also be noted that valves (not shown, but commonly taking the form of a temporarily displaceable ball) must be positioned at the inlet and outlet in order to allow for proper operation of the pump 1.
[0059] Despite these shortcomings, the design of pump 1 has been attractive because of its reliability in consistently dispensing larger doses. Additionally, to the extent spring 8 was made of metal, this prior art design can isolate and prevent the spring from coming into direct contact with the fluid by positioning the spring around the outside of the stem 3, although this further dictates and necessitates a comparatively constricted inlet area 7b (as well as outlet area 7a).
[0060] With reference to
[0061] The actuator 20 includes a channel 23 defined by extension 21 and nozzle/outlet 22. Notably, the nozzle 22 may include an open ended or valve controlled opening 221 (with the valve possibly including a duckbill or other similar anti-drip mechanism). Alternatively, nozzle 22 may be closed by a distribution panel 222 having a plurality of apertures arranged to provide a desired dispensing or spraying pattern.
[0062] During actuation, the actuator 20 and piston 30 move in unison and in a reciprocating fashion (owing to the biasing force exerted by spring 80) through the pump chamber 60a. Chamber 60a is generally defined by housing 60, which nested within the upper reaches 51 of closure cap 50.
[0063] Piston 30 has an enlarged lower end 31 that is configured to conform and seal to an inner surface of the pump chamber 60a. As such, both the pump housing and the piston have cooperating, and preferably circular, transverse shapes (i.e., the transverse plane running within horizontal plane of
[0064] Lower portion 31 includes a radial flange 311 having a sealing wiper 312. This wiper seals to the inner facing of the housing wall to alter the volume of the chamber 60a and create suction as the actuator 20 is urged upward. Notably, the outer-most edge (usually at its distal end) of the wiper 312 has substantially the same diameter D3 as the inner facings of the housing 60. Also, as seen in
[0065] That body 60 includes one or a plurality of vent holes 62 at its top, open end, imparting a cup shape but with a central aperture sized to receive flap or disc valve 61b. The valve 61b can be seated proximate the inlet aperture 63 in a well 633 defined by a raised annular ridge 632 that couples to the side wall by radial flange 631. The inner facing of the cylindrical walls 65 will be smooth so as to maintain a seal with the piston 30.
[0066] As noted above, radial ledge 53 include an extension 531 to couple to the body 60. On an opposing/lower facing of ledge 53, a tubular extension 521 protrudes coaxially downward, including ribs or grooves, to couple to a dip tube 60b.
[0067] The housing is sealed by an annular collar 40. The aperture in the collar 40 is sized to receive the middle portion 32 of piston while retaining its lower end 31 inside the pump chamber 60a. The collar 40 includes an outer skirt 41 offset from a plug seal extension 42, with these elements spaced apart to snap-fit to the top edge of the housing 60, thereby creating an air-tight seal.
[0068]
[0069] Member 80a is formed as a resilient, spiraling cone in which the sidewalls compress and expand to provide the biasing force to extend the actuator 20 away from the cap 50. Its top end 81a may be larger in comparison to its bottom end 82a, and both may be provided with a reinforced flange. When present, the reinforced flange can include radial and/or axial projections 83 to facilitate coupling the biasing member to adjacent components. Projections 83 may also provide spacing for fluid flow in some aspects, and these projections could be employed at other interfaces along the fluid flow paths of the pump 10, including proximate to the inlet on the housing 60 and/or closure 50 (i.e., the liquid flow path running through the diptube, into the pump chamber, and out the actuator and/or the make up air flow path that passes between the collar/closure and the piston and through the vent apertures of the pump housing).
[0070] Other all-plastic biasing member designs include both the inventions and prior art solutions described in International Patent Publications WO2022/038199A1 and WO2022/038194A1, both of which are incorporated by reference. Still other solutions and designs are apparent to persons of skill in this field, who will appreciate the shortened axial travel and unique configuration of the piston and pump chamber are more pertinent to the technical solutions (in comparison to the precise form of the spring/biasing member).
[0071]
[0072]
[0073] Still other iterations and features are illustrated in the figures. By way of example rather than limitation, the collar 40 fitted atop the housing 60 may include bead-and-groove features to couple to the top edge of the housing (e.g., between housing 50 and dip tube 60b, etc.). This fitment is equally applicable to other coupled components throughout the pump 10. The valves 61a, 61b can be free-floating discs or, as shown in
[0074] All components should be made of materials having sufficient flexibility and structural integrity, as well as a chemically inert nature. The materials should also be selected for workability, cost, and weight. Common polymers amenable to injection molding, extrusion, or other common forming processes should have particular utility, although metals, alloys, and other composites may be used in place of or in addition to more conventional container and closure materials.
[0075] References to coupling in this disclosure are to be understood as encompassing any of the conventional means used in this field. This may take the form of snap- or force fitting of components, although threaded connections, bead-and-groove, and slot-and-flange assemblies could be employed. Adhesive and fasteners could also be used, although such components must be judiciously selected so as to retain the recyclable nature of the assembly.
[0076] In the same manner, engagement may involve coupling or an abutting relationship. These terms, as well as any implicit or explicit reference to coupling, will should be considered in the context in which it is used, and any perceived ambiguity can potentially be resolved by referring to the drawings.
[0077] Although the present embodiments have been illustrated in the accompanying drawings and described in the foregoing detailed description, it is to be understood that the invention is not to be limited to just the embodiments disclosed, and numerous rearrangements, modifications and substitutions are also contemplated. The exemplary embodiment has been described with reference to the preferred embodiments, but further modifications and alterations encompass the preceding detailed description. These modifications and alterations also fall within the scope of the appended claims or the equivalents thereof.