Roll-on liquid applicators for dispensing a liquid in a controlled amount may employ a spring-biased ball which is captured within an upper chamber of a housing. In this style of applicator the ball is movable between a first or closed position and a dispensing position where the ball is moved away from an edge of the housing. Applicators of this type typically rely on sealed interfaces, not only around the ball, but with other components which are received within the housing. The effectiveness and reliability of these sealed interfaces is an important design consideration. When roll-on liquid applicators are used for dispensing a low-viscosity liquid, the design considerations for effective and reliable sealing take on added importance.
When this type of roll-on liquid applicator is not in use, it is important to prevent evaporation loss of the liquid. This design consideration is applicable for the primary liquid reservoir or supply and is applicable for the staged liquid supply which may be in a chamber which is in flow communication with and/or in direct contact with the ball. As these design aspects are evaluated relative to the potential for an improved construction, the cost of the component parts, the ease of assembly of those parts and the reliability of the fits between mating parts, including sealing integrity and overall performance, take on added importance. While the focus of the present disclosure is on a roll-on “liquid” applicator the actual construction and the design of the component parts would be applicable to any flowable media, whether a low-viscosity liquid or a flowable media with a higher viscosity. In fact, even certain powder compositions could be classified as “flowable” and the only design considerations which would have to be made would be on the size of clearance spaces and/or flow openings such that the selected flowable media would be able to pass therethrough.
When a selected manner of sealing the interface between two (2) structures introduces variables which are difficult to control or when the structures are more costly to produce, a new construction offers opportunity for improvement. For example, trying to establish a sealed interface between a conical surface and an annular edge typically leaves little margin for error if the intended area of contact is a relatively narrow line. Under these conditions, if either surface is slightly out of round or warped, the abutment between these two (2) components could leave gaps or separation which could be susceptible to liquid leakage and/or evaporation of some portion of the liquid supply, depending in part on the viscosity of the liquid. Evaporation is a greater concern when a highly volatile liquid is going to be dispensed by the applicator.
Some designs introduce component part complexities which are less reliable in terms of their fit, sealing and performance and at the same time these component parts may be more expensive to produce. If these same part complexities create abutment interfaces which are difficult to seal, a new construction offers opportunities for improvement. It might be possible to improve the overall construction of these types of roll-on applicators by the use of an additional component part. Although a reduction in the number of component parts might be thought of as always being a desirable design pursuit, sometimes adding a part can contribute to the overall reliability and performance of an assembly. This is the case with the roll-on applicator of the present disclosure.
The disclosed roll-on applicator includes a housing, a ball which is captured within the housing, a valve and a sealing insert positioned between the ball and the valve. The valve includes a spring member for spring-biasing the ball. Use of the roll-on applicator applies a force to the ball and moves the ball from a first position or starting position through an intermediate position to an ending position. The sealed condition which is achieved in the ending position is between the sealing insert and a ledge of the housing. The shape characteristics of the sealing insert and the housing ledge establish a more reliable sealed interface as compared to other designs such as pushing a ball against an annular corner or edge. The disclosed roll-on applicator provides a wider annular ring area of abutment contact as compared to earlier designs which create what is essentially an annular line of abutment contact between the ball and an annular corner or edge.
This larger area of abutment contact which is provided by the roll-on applicator disclosed herein is the result of adding the sealing insert and positioning this insert between the ball and the referenced ledge of the housing. This housing ledge includes a depending annular lip which in one position abuts up against an annular surface of the valve. Adding a tapered shape to the annular lip adds flexibility to the tip and thereby enhances the integrity and reliability of the seal. This type of abutment interface provides more reliable sealing as compared to a conical surface being pushed against an annular corner or edge, something which is considered to be a deficiency found in earlier roll-on applicator constructions.
For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates. One embodiment of the invention is shown in great detail, although it will be apparent to those skilled in the relevant art that some features that are not relevant to the present invention may not be shown for the sake of clarity.
Referring to
In the upright position or orientation of
When the applicator 20 is used in a normal or intended manner to apply or dispense a portion of the liquid within housing 26, the applicator 20 is tilted (or inverted) so as to enable gravity feed of liquid onto the surface of the ball. Then as the ball rolls, liquid is applied to a surface. Depending on the positioning and orientation of the surface to be contacted by the ball 28, the applicator 20 could be completely inverted so as to direct the ball 28 downwardly as opposed to simply tilting the applicator 20 at some angle of incline. As the ball 28 is moved across the selected surface, surface friction causes the ball 28 to turn or rotate within housing 26 and to roll on axis. As the ball rolls, a liquid coated portion of the outer surface of the ball 28 moves into contact with the surface and transfers liquid onto the surface.
In the context of the present disclosure, the focus is on applying a liquid to the surface. The viscosity of this liquid will have an influence on the extent or magnitude of any flow gaps or separation which may need to be established in order for the liquid to coat the ball and for that liquid to be applied to a surface as the ball rolls. If a more viscous liquid is selected for dispensing from roll-on applicator 20, additional clearance or separation might be required between some of the components parts of roll-on applicator in order to allow this more viscous liquid to properly flow in the intended manner of use associated with roll-on applicator 20. It is also anticipated that the construction and arrangement of roll-on applicator 20 would be suitable to apply a flowable powder and for this reason a more generic reference to the material to be applied to the work surface is a “flowable media” which is intended to encompass not only liquids of various viscosities, but other materials which could be applied by means of roll-on applicator 20.
The additional component parts of roll-on applicator 20 include a spring-biasing valve 42 and a sealing insert 44 (see
With continued reference to
The annular opening 72 is defined in part by the upper portion 61 and in part by lower portion 34. Adjacent the lower edge 76 of the opening 72 is a depending sealing lip 78 which has a tapered shape, converging in a downward direction to a tip. The lower chamber 74 has a generally cylindrical shape and receives a majority of valve 42. As illustrated in
The flow opening which is defined in part by shelf 64 and defined in part by lower portion 34, in particular by sealing lip 78, can be thought of as a transition flow opening 72 between the upper chamber 62 and the lower chamber 74. Further, whenever reference is made herein to a particular component or a portion of a component being “received” within a certain chamber, volume or space, that is to be interpreted as having at least a portion of that component part or structure as being actually received in the identified chamber, volume or space. For example, the valve would properly be described as being received within the lower chamber 74, even though a portion of the valve head extends into the transition flow opening between the two (2) chambers. Similarly, the sealing insert 44 could be described as being received within the upper chamber 62 even though the frustoconical lower portion 86 of the sealing insert 44 extends into that transition flow opening between the two (2) chambers.
The sealing insert 44 is constructed and arranged as a single-piece, unitary, elastomeric member with an annular upper portion 80 which defines a generally concentric, part-spherical depression 82. Depression 82 is sized and shaped so as to generally match part of the generally spherical size and shape of ball 28. This size and shape compatibility between depression 82 and the surface of ball 28 allows the ball to seat fully in depression 82 with an area of contact between these two components. The underside surface 84 of upper portion 80 is annular and substantially flat so as to be able to seal against the upper surface of shelf 64 with an area of contact (See
The annular lower portion 86 of sealing insert 44 is tapered (i.e. frustoconical) so as to generally correspond to the size and shape of frustoconical recess 56. This size and shape compatibility allows the lower portion 86 to fit into recess 56 with a snug fit. Based on this snug fit, the valve head 46 and sealing insert 44 move together as a single unit. Lower portion 86 is generally concentric with upper portion 80 and with depression 82.
There are three (3) position orientations for roll-on applicator 20 and these three (3) position orientations are illustrated in
A second position and orientation of applicator 20 is represented by
As the ball 28 is initially pushed against the work surface which is to receive a line of liquid from applicator 20 with a moderate level of force, the ball 28 pushes inwardly against the valve 42. If the force applied against the upper portion 30 of the ball exceeds the spring force of spring 48, the ball moves inwardly, a very slight distance, away from upper edge 32. This movement creates a slight separation between the ball 28 and the upper edge 32 which makes it easier for the ball to roll and for liquid on the surface of the ball to be applied to the work surface. During this initial movement of the ball 28, as represented by
With increased pushing force on ball 28, additional movement occurs and this position and orientation are presented by the
The use of sealing insert 44 enables certain design decisions for the valve 42 and for the housing 26 which are considered to be beneficial to the overall design and construction of ball-captured, roll-on applicators. One of the important considerations for roll-on applicators is the integrity and reliability of the various seals and sealed interfaces. One feature of sealing insert 44 is the part-spherical depression 82 which matches the size and shape of the generally spherical ball 28. This construction provides a larger area of sealing contact and should minimize any sealing issues which might result from having only a point or line contact for the designed sealing. Additionally, the upper portion 80 has an annular-ring shape and a relatively large annular underside surface 84 which is adjacent the upper surface of shelf 64. Here again, when sealing contact is made between surface 84 and shelf 64, there is a relatively large area of abutment and sealing contact. This large area of sealing contact should minimize any sealing issues which might result from having only point or line contact for the desired sealing.
The use of sealing insert 44 also facilitates the specific design selected for valve head 46 and the specific design selected for sealing lip 78. These two (2) portions cooperate to establish a sealed interface at their location of abutment. For this sealed interface the valve head supplies an area for the contact in the form of the annular-ring shape of ledge 58. Since sealing lip 78 tapers to a smaller depending tip, it is expected that with the use of plastic components some compression and spreading of that smaller depending tip will occur due to abutment against ledge 58. This compression of the plastic tip increases the area of contact with ledge 58 and thereby should provide an improved seal at this abutment interface.
An alternative valve construction for applicator 20 is illustrated in
In the alternative valve construction of
While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes, equivalents, and modifications that come within the spirit of the inventions defined by following claims are desired to be protected. All publications, patents, and patent applications cited in this specification are herein incorporated by reference as if each individual publication, patent, or patent application were specifically and individually indicated to be incorporated by reference and set forth in its entirety herein.
This application claims the benefit of U.S. Provisional Application Ser. No. 61/667,478 filed Jul. 3, 2012, which is hereby incorporated by reference in its entirety.
Number | Date | Country | |
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61667478 | Jul 2012 | US |