Improvements in or relating to pump sprayers

Abstract: The disclosure relates to a pump sprayer (10) as having a container closure (11) for mounting the sprayer on a container of liquid product to be sprayed. Hollow stem (12) of the pump piston extends through a central opening in crown portion (13) of the closure for reciprocation within a pump cylinder. A plunger head (14) is mounted on the stem of effect piston reciprocation upon application of a downward finger force applied to finger pad (15) of the plunger head against the spring bias of the piston return spring. The head includes a laterally extending spinner probe (18) surrounded by an orifice cup (19) having a coaxial discharge orifice (21). The inner front face of the orifice cup is provided with a plurality of tangential channels (22) terminating at the downstream end thereof in a central spin or swirl chamber (23) where he swirling particles break up in the atmosphere as a spring core. Some of the spin velocity is negated to produce a more narrow spray cone by the provision of an opening (26) in probe (18) extending from the downstream end of the tangential channels (22). The piston stem is provided with at least one opening (27) in alignment with opening (26) to establish a second fluid path communicating with passage (16).

Description: This invention relates generally to a fine mist sprayer having a reciprocable hollow piston stem on which a fingertip actuated plunger is mounted for the pumping of fluid. Spin mechanics of some known type are provided for imparting a spin or swirl at a given velocity for issuance through the discharge orifice as a fine mist spray having a predetermined spray cone. More particularly, the invention relates to a means establishing a second fluid flow path for diverting some of the fluid from the discharge passage to the spin mechanics to negate some of the spin velocity and thereby cause the spray to issue as a narrower spray cone. The second fluid path may be selectively opened and closed to regulate the size of the spray cone. Known pump sprayers typically have some type of spin mechanics for imparting a spin or swirl to the fluid at a given velocity to issue through the discharge orifice as a fine mist spray which breaks up in the atmosphere in the form of a divergent spray cone of given size. For this purpose an orifice cup has a spin chamber coaxial with the discharge orifice, and tangential channels lead into the spin chamber. Longitudinal channels leading in the tangentials are formed between a post or a probe and the surrounding orifice cup to establish a flow path from the discharge passage formed in the hollow piston stem. The orifice cup and probe are mounted within a plunger head coupled to the stem for reciprocation of the stem upon manual depression of the head. US-A-4074861, for example, which represents the prior art as referred to in the preamble of claims 1 and 14, discloses a pump sprayer on a closure for a liquid holding container. The sprayer comprises a pump piston having a hollow stem which extends through a central opening in a crown portion of the closure for reciprocation within a pump cylinder. A plunger head is mounted on the stem to affect piston reciprocation upon application of a downward finger force applied to a finger pad of the plunger head against the spring bias of the piston return spring. The hollow piston stem then defines a fluid discharge passage which communicates at its upper end with a lateral pathway in the head and the head includes a laterally extending spinner probe surrounded by an orifice cup having a co-axial discharge orifice. The inner front face of the orifice cup is provided with a spin mechanics arrangement including a plurality of tangential channels terminating at the downstream end thereof in a central spin or swirl chamber. Longitudinal channels formed between the orifice cup and probe communicate with the tangential channels and form a first fluid path, together with an annular opening and lateral pathway, the path communicating with the aforesaid passage in the hollow piston stem. During pumping, liquid is discharged as a fine mist spray via the spin mechanics which impart swirl or spin to the liquid to discharge through the orifice and break up in the atmosphere as a diverging spray cone or plume. For certain applications it is desirable to provide a narrower spray cone using the existing spin mechanics structure, the less divergent spray cone satisfying the need for reducing the area of spray against a target of a given size to be wetted during pumping operation. Also, it would be beneficial to selectively var the size of the spray cone in a simple and efficient manner using existing spray mechanics without complicating the structure and avoiding the need for additional molded parts. An object of the invention is to provide an improved fine mist sprayer capable of issuing a less divergent, narrower spray compared to the conventional sprayer in a simple and efficient yet highly effective manner by negating some of the tangential velocity imparted to the fluid at the discharge orifice. This invention provides a pump sprayer having a hollow piston stem defining a single liquid discharge passage through which liquid passes upon pumping, said piston stem being reciprocable during pumping within a container closure, a plunger head mounted on said stem and having a probe extending transversely from said stem, a nozzle cap surrounding said probe, said cap having a discharge orifice and means including a spin chamber in communication with said orifice for imparting a spin at a given velocity to the liquid to be discharged through said orifice as a fine mist spray having a predetermined spray cone, said plunger head and said nozzle cap having means defining a first liquid fluid path extending from said discharge passage to said orifice via said spin imparting means through which the liquid passes; wherein the probe has a through opening defining a second liquid path communicating directly with said single liquid discharge passage and with said spin chamber for diverting some of the liquid from said single liquid discharge passage into said second liquid path to said spin chamber for negating the given velocity to produce a spray cone more narrow than the predetermined spray cone. This invention provides also a plunger sprayer according to claim 14. The plunger head may be rotated about the stem between a position misaligning the probe and stem openings for directing fluid through only the first fluid path to produce a normal fine mist spray of a given spray velocity, and a position aligning the probe and stem openings for directing fluid from the discharge passage through both fluid flow paths to produce a fluid spray of a reduced velocity and a narrower spray plume. Cooperating means acting between the stem and a closure for the pump sprayer resists rotation of the stem upon head rotation. Stop means acting between the piston stem and the plunger head limit head rotation to the misaligned and aligned positions. And, limit stops on the head and/or the closure may be provided for limiting the reciprocation travel of the stem to thereby limit the output of the sprayer. Other objects, advantages and novel features of the invention will become more apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings, in which: Figure 1 is a fragmentary vertical sectional view of a fine mist sprayer incorporating the present invention; Figure 2 is a fragmentary vertical sectional view of the modified piston stem of Figure 1; Figure 3 is a view taken substantially along the line 3-3 of Fig. 1; Figure 4 is a view taken substantially along the line 4-4 of Fig. 1; Figure 5 is a view taken substantially along the line 5-5 of Fig. 1; Figure 6 is a view similar to Figure 5 showing the plunger head rotated relative to the piston stem; Figure 7 is a fragmentary view of the upper end of the piston end showing one embodiment of an opening provided in the stem; and Figure 8 is a view similar to Figure 7 showing another embodiment of an opening provided at the upper end of the piston stem. Turning now to the drawings wherein like reference characters refer to like and corresponding parts throughout the several views, the pump sprayer is generally designated 10 in Figure 1 as having a container closure 11 for mounting the sprayer on a container (not shown) of liquid product to be sprayed upon pumping. Hollow stem 12 of the pump piston extends through a central opening in crown portion 13 of the closure for reciprocation within a pump cylinder (not shown) in the normal manner. A plunger head 14 is mounted on the stem to effect piston reciprocation upon application of a downward finger force applied to finger pad 15 of the plunger head against the spring bias of the piston return spring (not shown). The hollow piston stem defines a fluid discharge passage 16 which communicates at its upper end with a lateral pathway 17 in head 14. The head includes a laterally extending spinner probe 18 surrounded by an orifice cup 19 having a coaxial discharge orifice 21. The inner front face of the orifice cup is provided with some type of known spin mechanics including a plurality of tangential channels 22 (only one shown in Fig. 1) terminating at the downstream end thereof in a central spin or swirl chamber 23. Longitudinal channels 24 formed between the orifice cup and probe 18 communicate with tangential channels 22 and form a first fluid path together with an annular opening 25 and lateral pathway 17, such path communicating with passage 16. The aforedescribed structure of spin mechanics and first fluid path is set forth in more detail in U.S. Patent 4,074,861, commonly owned herewith. During pumping operation product is discharged through passage 16 and the first fluid path as a fine mist spray via the spin mechanics which impart a swirl or spin to the fluid at a given velocity for issuance through the discharge orifice where the swirling particles break up in the atmosphere diverging as a spray cone or plume of a given conical size. According to the invention some of the spin velocity is negated to produce a more narrow spray cone. This is effected by the provision of an opening 26 in probe 18 extending from the downstream end of the tangentials 22 at spin chamber 23 and terminating at piston stem 12. The piston stem is provided with at least one opening 27 which, in the Figs 1 and 5 position, is in alignment with opening 26 to establish a second fluid path communicating with passage 16. During pumping upon reciprocation of the plunger in its relative position to the piston stem shown in Figs. 1 and 5, fluid is discharged through passage 16 and through the first fluid flow path 17, 25, 24 as it is swirled in chamber 23 at a given velocity. And, during such pumping operation, some of the fluid is diverted from passage 16 into the second fluid path 27, 26 for negating some of the tangential velocity occurring in chamber 23 to effect a discharge of fluid through orifice 21 as a divergent spray having a cone size more narrow than the size of a spray cone produced by the pumping of fluid only through passage 16 and the first fluid flow path. When the plunger head is rotated about the stem from its Fig. 5 position at which openings 26 and 27 are in alignment, to its Fig. 6 position at which openings 26 and 27 are out of alignment, any diversion of fluid through the second fluid flow path is blocked such that the discharge of fluid passes only through the first fluid flow path for issuing as a divergent spray having a normal cone size determined by the full spin velocity imparted to the fluid by the tangential channels. To resist rotation of stem 12 upon plunger head rotation, the stem has one or more (three being illustrated in Fig. 3) external longitudinal ribs 28 of a given configuration mating with longitudinal grooves 29 (Fig. 4) of a corresponding shape located in central sleeve 30 which depends from crown piston 13 of closure 11. And, limit stops are provided for limiting relative rotation of the plunger head between its Fig. 5 and its Fig. 6 positions. Such limit stops may be in the form of equally spaced lugs 31 extending radially inwardly from wall 32 of inner skirt 33 of the plunger head. The upper ends of ribs 28 of the stem contact one side of lugs 31 in the Figure 5 position, and contact the other side of lugs 31 in the plunger head rotative position of Fig. 6. It is to be noted that other openings 27A and 27B are provided at the upper end of stem 12 although only opening 27 in the illustration is aligned and misaligned with opening 26 upon plunger head rotation. Openings 27, 27A and 27B are equally spaced, and openings 27A and 27B are provided for facilitating the sub-assembly of the plunger head and the piston stem without the need for indexing. Thus, with three openings 27, three lugs 31 and three ribs 28, the plunger head can be initially oriented during assembly with the piston stem in the Figure 5 or in the Figure 6 position without the need for complicated indexing. As seen in Figure 7, each opening 27 may be in the form of an open notch having spaced, parallel side edges. Otherwise, an opening 33 may be formed at the upper end of the plunger stem which, as shown in Figure 8, has a sloping bottom wall 34 to effect a partial blocking and unblocking of opening 26 upon relative head rotation. Thus, with the Figure 8 embodiment, the second fluid flow path ca be placed in service between a totally blocked position and a gradually open position for varying the spray cone within a range of that achieved by relative head rotation between a fully aligned Figure 5 position and the fully misaligned Figure 6 position. Another advantageous feature is the provision of limit stops for limiting stem reciprocation to thereby meter the volume of spray out of the orifice. For this purpose, dependig legs 35 may be provided on skirt 33 and/or upstanding legs 36 on crown portion 13 of closure 11. Lugs 35, if oriented to axially align with legs 36, will bear against legs 36 at the end of the downward travel of the plunger head to thereby limit piston reciprocation and thereby meter the amount of discharge from the sprayer. If only legs 35 are provided they will simply impart against crown portion 13 to limit the downward travel of the plunger head and piston. And, if only legs 36 are provided they will impart against the underside of sleeve 33 to limit downward travel of the plunger head and piston. Obviously many other modifications and variations may be made to the above embodiments without departing from the scope of the invention as defined in the claims. For example, other forms of spin mechanics than than illustrated and described can be provided and means other than ribs and grooves 28 and 29 could be provided for resisting stem rotation upon plunger rotation.

Claims: A pump sprayer having a hollow piston stem (12) defining a single liquid discharge passage (16) through which liquid passes upon pumping, said piston stem being reciprocable during pumping within a container closure (30), a plunger head (14) mounted on said stem and having a probe (18) extending transversely from said stem, a nozzle cap (19) surrounding said probe, said cap having a discharge orifice (21) and means including a spin chamber (23) in communication with said orifice for imparting a spin at a given velocity to the liquid to be discharged through said orifice as a fine mist spray having a predetermined spray cone, said plunger head and said nozzle cap having means (17, 25, 24) defining a first liquid fluid path extending from said discharge passage (16) to said orifice (21) via said spin imparting means through which the liquid passes; characterised in that the probe (18) has a through opening (26) defining a second liquid path communicating directly with said single liquid discharge passage (16) and with said spin chamber (23) for diverting some of the liquid from said single liquid discharge passage into said second liquid path to said spin chamber for negating the given velocity to produce a spray cone more narrow than the predetermined spray cone. A sprayer as claimed in claim 1, characterised in that said plunger head (14) is relatively rotatable on said stem (12) about a central axis thereof, an outer end of said stem having at least one opening (27) capable of being aligned and misaligned with said probe opening (26) for uncovering and blocking said probe opening depending on the relative rotative position of said plunger head. A sprayer as claimed in claim 2, characterised in that said stem opening comprises a notch (27) having a predetermined width. A sprayer as claimed in claim 3, characterised in that said stem opening comprises a notch having a tapered lower edge (34) for gradually uncovering said probe opening (26) upon the rotation of said plunger head to gradually regulate the size of the spray plume. A sprayer as claimed in any of claims 2 to 4, characterised in that cooperating means (28, 29) are provided between said stem (12) and said closure (30) to resist rotation of said stem upon plunger head rotation. A sprayer as claimed in any of claims 2 to 4, characterised in that cooperating stop means (28, 31) are provided between said plunger head (14) and said stem (12) for limiting plunger head rotation into position aligning and misaligning said stem opening (27) and said probe opening (26). A sprayer as claimed in any of claims 2 to 4, characterised in that first limit stop means (35) is provided on said plunger head (14) for limiting stem reciprocation to control the output of said sprayer in a given rotative position of said plunger head. A sprayer as claimed in claim 7, characterised in that said first limit stop means comprises at least one depending leg (35) for contact with said closure (30). A sprayer as claimed in claim 7 or claim 8, characterised in that second limit stop means (36) is provided on said closure (30) for abutting engagement by said first limit stop means for limiting stem reciprocation. A sprayer as claimed in claim 9, characterised in that said second limit stop means comprises at least one upstanding leg (36) on said closure (30). A sprayer as claimed in claim 5, characterised in that said cooperating means comprises longitudinally extending ribs (28) and grooves (29) on said stem (12) and said closure (30). A sprayer as claimed in claim 6, characterised in that said stop means comprise radially extending spaced lugs (31) on said plunger head (14) and radially extending spaced ribs (28) on said stem (12). A sprayer as claimed in claim 12, characterised in that said ribs (28) mate with corresponding grooves (29) provided in said closure (30) for resisting rotation of said stem upon head rotation. A plunger sprayer comprising: a hollow piston stem (12) reciprocable within a container closure and defining a fluid discharge passage (16); a plunger head (14) on said stem having fluid spray means (21) and a first fluid path (17, 25, 24) extending from said discharge passage to said spray means (21); said spray means including a spinner probe (18); said stem (12) having at least one opening in communication with said passage (16); characterised in that: said spinner probe (18) has a through opening (26) terminating at said stem (21) and said through opening (26) defines a second liquid path communicating directly with said fluid discharge passage (16) and with said spinner probe (18); and said plunger head (14) is rotatable about said stem into a position misaligning said openings (26, 27) for directing fluid from said passage (16) through only said first path (17, 25, 24) to produce a fluid spray of a given velocity; and said plunger head (14) is rotatable about said stem (12) into a position aligning said openings (26, 27) for directing fluid from said passage (16) through both said paths to produce a fluid of a reduced tangential velocity compared to said given velocity and of a narrow spray plume. A sprayer as claimed in claim 14, characterised in that said stem opening comprises at least one notch (27) having a given width. A sprayer as claimed in claim 14, characterised in that said stem opening comprises a notch having a tapered lower edge (34) for gradual alignment with said probe opening upon head rotation to gradually regulate the size of the spray plume. A sprayer as claimed in claim 14, characterised in that cooperating means (28, 29) on said stem (12) and said closure (30) are provided for resisting stem rotation upon head rotation. A sprayer as claimed in claim 17, characterised in that said cooperating means comprise mating ribs (28) and grooves (29). A sprayer as claimed in claim 14, characterised in that cooperating stop means (28, 31) are provided on said stem (12) and said head (14) for limiting head rotation to said misaligning and aligning positions. A sprayer as claimed in claim 18, characterised in that said ribs (28) are located on said stem (12), and lugs (31) are provided on said plunger head (14) for engaging said ribs for limiting plunger head rotation to said misaligning and aligning positions. A sprayer as claimed in claim 19, characterised in that said stop means comprise radially spaced cooperating lugs (31). A sprayer as claimed in claim 14, characterised in that at least one first limit stop (35) is provided on said head (14) for limiting the reciprocation travel of said stem to thereby limit the output of the sprayer. A sprayer as claimed in claim 22, characterised in that said first limit stop comprises a depending leg (35) adapted to impact said closure (30). A sprayer as claimed in claim 14, characterised in that at least one second limit stop (36) is provided on said closure (30) for limiting the reciprocation travel of said stem to thereby limit the output of the sprayer. A sprayer as claimed in claim 24, characterised in that said second limit stop comprises an upstanding leg (36) adapted to impact said head.

Inventors: GROGAN R PAT, GROGAN, R. PAT
Applicants: CALMAR INC, CALMAR INC.
Application year: 1995
Main classification: B05B11
IPC codes: B05B11, B05B1