EP1761339A2

EP1761339A2 - Trigger sprayer with venting membrane

Info

Publication number: EP1761339A2
Application number: EP05731014A
Authority: EP
Inventors: Donald D. Foster
Original assignee: Stark Jeffrey P; Continental AFA Dispensing Co Inc
Current assignee: Stark Jeffrey P; Continental AFA Dispensing Co Inc
Priority date: 2004-03-25
Filing date: 2005-03-24
Publication date: 2007-03-14
Also published as: WO2005094492A2; CN101421049A; JP2007527831A; WO2005094492A3

Abstract

A trigger sprayer is provided with a passive venting system of simplified and inexpensive construction. A gas permeable, liquid impermeable membrane is positioned over a vent opening in the trigger sprayer housing and prevents the leakage of liquid from a container attached to the trigger sprayer, while allowing the venting of air from the exterior of the trigger sprayer to the container interior. The membrane is secured to a vent opening wall of the sprayer housing that is positioned coplanar and continuous with an annular surface of the sprayer housing. This enables the use of a single flat gasket to seal around the vent opening and seal between the trigger sprayer and the liquid container attached to the trigger sprayer.

Description

TRIGGER SPRAYER WITH VENTING MEMBRANE

Background of the Invention

(1) Field of the Invention The present invention pertains to a trigger sprayer which is connectable to a separate liquid container, where the trigger sprayer has a trigger that is manually manipulated to pump liquid from the container, and dispense the liquid from the trigger sprayer as a spray, stream, or foam. In particular, the present invention pertains to a venting membrane that is secured in the trigger sprayer to permit venting of air into the interior volume of the container as liquid is dispensed from the container, and a gasket that seals the trigger sprayer to the container.

(2) Description of the Related Art The present invention pertains to a trigger sprayer which is connectable to a separate container containing a liquid. The trigger sprayer has a trigger that is manually manipulated to operate a pump in the trigger sprayer. The pump draws liquid from the liquid container, through the trigger sprayer, and dispenses the liquid from the trigger sprayer as a spray, stream, or foam. There are many different systems employed in the construction of conventional trigger sprayers that allow for the venting of air to the interior of the liquid container connected to the trigger sprayer. The venting systems of trigger sprayers allow air to enter the container and occupy the container internal volume vacated by liquid dispensed from the container by the trigger sprayer. Venting of the container interior volume is required because the connection between the container and the trigger sprayer is typically a fluid-tight connection. This prevents the inadvertent leakage of the liquid contents of the container should the container and attached trigger sprayer be inverted or positioned on their sides. The fluid-tight connection between the container and the trigger sprayer is typically provided by a gasket positioned between the upper rim of a neck of the container and a bottom annular surface of the trigger sprayer housing. The connector that attaches the trigger sprayer to the container compresses the gasket between the container neck and the annular surface of the trigger sprayer housing, thereby providing the fluid- tight seal between the trigger sprayer and the container. However, the fluid-tight seal between the trigger sprayer and the container makes it difficult to vent the interior of the container as liquid is dispensed from the container. To maintain the fluid-tight connection between the trigger sprayer housing and the container, prior art venting systems have required elaborate constructions that add to the manufacturing costs of the trigger sprayer. For example, one typical venting system employs a resilient diaphragm valve that covers a vent hole in the sprayer housing that communicates the interior of the container with the container exterior environment, and a plunger connected to the trigger of the trigger sprayer. On manipulation of the trigger, the plunger is inserted through the sprayer housing vent hole and presses against the diaphragm valve, moving the diaphragm valve away from the vent hole and thereby venting the interior of the container. This type of venting system has been found to be disadvantaged in that the resiliency of the material of the diaphragm often does not enable the diaphragm valve to immediately position itself over the vent hole when the plunger is retracted. This can result in liquid leaking from the container through the vent hole. Providing the resilient diaphragm valve and the plunger in the trigger sprayer construction also increases the cost of construction. Another prior art venting system employs a small vent piston that reciprocates with the trigger and the pump piston of the trigger sprayer. The vent piston reciprocates in a vent chamber formed in the sprayer housing. As the vent piston is pushed into the vent chamber, the piston uncovers a vent hole that allows the container interior to be vented to the exterior environment. As the vent piston is pulled through the vent chamber and covers the vent hole, the container interior is again sealed from the exterior environment. The constructions of the these types of venting systems require that the sprayer housing be formed with an additional vent chamber, and that the trigger and/or pump piston be formed with an additional vent piston, increasing the manufacturing costs of the trigger sprayer. What is needed to overcome these disadvantages of prior art trigger sprayers is a venting system that enables the interior of the container connected to the trigger sprayer to be vented, while maintaining the gasket fluid-tight seal between the trigger sprayer and without appreciably increasing the manufacturing costs of the trigger sprayer. Summary of the Invention The construction of the trigger sprayer of the present invention overcomes the aforesaid disadvantages typically associated with prior art trigger sprayers by providing a trigger sprayer housing with a passive venting system that does not require movable parts and their associated costs. The venting system of the invention comprises a vent hole in the trigger sprayer housing that vents air to the interior volume of the container attached to the trigger sprayer, where the vent hole is covered by a gas permeable, liquid impermeable membrane. The vent hole and membrane are positioned on the sprayer housing to enable the sprayer housing to be economically manufactured, while allowing the sprayer housing to vent the interior volume of the container attached to the trigger sprayer, and while maintaining the fluid-tight seal between the trigger sprayer and the container. The trigger sprayer of the invention is comprised of a housing constructed in two separate sections, a pump section and a vent section. The pump section and the vent section are constructed so that these two sections can be press fit or snap fit together in assembling the trigger sprayer. The housing pump section contains the component parts of the trigger sprayer that can be found in many conventional trigger sprayers. This housing section contains the pump chamber , as well as the liquid supply passage and the liquid discharge passage that communicate with the pump chamber. The bottom of the housing pump section has an opening dimensioned to receive the housing vent section. A pump piston is assembled in the pump chamber for reciprocating movement of the piston in the chamber. A trigger is mounted to the housing pump section for pivoting movement of the trigger. The trigger is operatively connected with the pump piston for reciprocating the pump piston in the pump chamber in response to the trigger being manually manipulated on the trigger sprayer. A liquid spinner or foamer or other similar component is assembled to the liquid discharge passage of the housing pump section, depending upon the desired pattern of liquid discharge from the trigger sprayer. A shroud is assembled over the pump section of the housing to give the trigger sprayer an ecstatically pleasing appearance. The vent section of the housing has a generally cylindrical configuration that is complementary to an interior configuration of the bottom opening of the housing pump section. This enables the two sections to be press fit or snap fit together by inserting the vent section into the pump section. A liquid supply tube extends through the vent section and communicates with the liquid supply passage of the housing pump section. A dip tube is attached to the liquid supply tube and extends into the liquid container attached to the trigger sprayer. A circular flange with an annular surface surrounds a bottom opening of the housing vent section. The annular surface is positioned on the housing vent section to engage against a gasket positioned between the trigger sprayer and the neck of the liquid container to which the trigger sprayer is attached. A vent wall on the housing vent section is coplanar and continuous with the annular surface. The vent wall has a vent opening that communicates and vents the interior of the container attached to the trigger sprayer with the exterior environment of the trigger sprayer. A membrane is secured to the vent wall covering over the vent opening. The membrane is a gas pervious/liquid impervious membrane. Thus, the membrane allows air to pass from the container interior through the membrane and the vent opening, but prevents the passage of liquid from the container interior through the membrane and the vent opening. The vent section of the housing also includes a plurality of posts that project through the bottom opening of the housing. The gasket is a flat, circular disk of typical gasket material. The gasket has a circular peripheral edge that matches the circular peripheral edge of the annular surface of the housing vent section. A plurality of holes pass through the gasket. The plurality of holes include a liquid supply hole positioned on the gasket to accommodate the dip tube of the trigger sprayer extending through the liquid supply hole. A vent hole also passes through the gasket in a position where the vent hole is positioned at the membrane covering the vent opening of the housing vent section. The gasket could also be provided with a plurality of post holes that receive the plurality of posts on the housing vent section to hold the gasket against the annular surface of the housing vent section. Alternatively, the gasket could be staked on the housing vent section by pressing the gasket, without post holes, on the ends of the post, thereby staking the gasket on the housing section. The novel configuration of the trigger sprayer housing provides the trigger sprayer with a passive venting system of simplified and inexpensive construction. The membrane employed over the vent opening prevents the leakage of liquid from the container through the trigger sprayer, while allowing the venting of air from the exterior of the trigger sprayer to the container interior. The coplanar positioning of the vent opening wall and the annular surface of the housing vent section enables the same gasket to be used to seal around the vent opening and seal between the trigger sprayer and the liquid container. Thus, the combination of these features provides a trigger sprayer that is economically manufactured, provides a fluid-tight seal between the trigger sprayer and the liquid container, and prevents the leakage of liquid from the container while allowing container venting.

Brief Description of the Drawings Further objects and features of the invention are set forth in the following detailed description of the preferred embodiment of the invention and in the drawing figures wherein: Figure 1 is a side view of the trigger sprayer of the invention with a portion of trigger sprayer broken away; Figure 2 is a bottom plan view of the trigger sprayer; and, Figure 3 is an exploded view of several of the component parts of the trigger sprayer.

Detailed Description of the Preferred Embodiment Figures 1-3 of the application show a trigger sprayer that is similar in construction to the trigger sprayers disclosed in the US Patents of Foster, et al. No. 5, 344,053 and No. 5,337,928, the disclosures of which are incorporated herein by reference. The passive venting system of the invention will be described as being employed in a trigger sprayer of the type disclosed in the above referenced patents. However, it should be understood that the venting system of the invention may be employed in a variety of different trigger sprayer constructions. The particular construction of the trigger sprayer disclosed herein is intended to be illustrative of one environment in which the venting system may be used, and is not intended as being limiting. Because the venting system of the invention may be used in a variety of different types of trigger sprayers, the component parts of the trigger sprayer that are not material to the construction and operation of the venting system of the invention will be described generally herein. As stated earlier, the construction of the trigger sprayer of the present invention overcomes disadvantages typically associated with prior art trigger sprayers by providing a trigger sprayer housing with a vent hole that vents air to the interior volume of the container attached to the trigger sprayer, where the vent hole is covered by a gas permeable, liquid impermeable membrane. The vent hole and membrane cover are positioned on the sprayer housing to enable the sprayer housing to be economically manufactured with a passive venting system, i.e., having no moving parts. The passive venting system allows the trigger sprayer to vent the interior volume of the container attached to the trigger sprayer, and while maintaining a fluid tight seal between the trigger sprayer and the container. Referring to the drawing figures, the trigger sprayer 12 of the invention is comprised of a housing constructed in two separate sections, a pump section 14 and a vent section 16. As their names suggest, the housing pump section 14 contains the pump of the trigger sprayer, and the housing vent section 16 contains the venting system of the invention. The pump section 14 and the vent section 16 are constructed so that they can be press fit or snap fit together in assembling the trigger sprayer 12. To facilitate this assembly, the two housing sections 14, 16 are constructed of a resilient plastic material typically used in the construction of trigger sprayers. The housing pump section 14 contains the component parts typically found in a conventional trigger sprayer. Because these component parts are well known, they are described generally. The housing pump section 14 contains a pump chamber 18, a liquid discharge passage (not shown) that communicates with and extends away from the pump chamber, and a liquid supply passage (not shown) that communicates with and extends to the pump chamber. The bottom of the housing pump section 14 has a generally cylindrical wall 22. The wall 22 surrounds a bottom access opening 24 to the interior of the pump section. The pump section wall 22 has a plurality of internal ribs 26 on an interior surface of the wall. The ribs 26 project into the bottom opening 24 of the pump section wall 22 and provide a portion of the press fit or snap fit connection between the pump section 14 and the vent section 16. The pump section bottom opening 24 is dimensioned to receive the vent section 16 therein, in assembling the vent section to the pump section. As in conventional trigger sprayers, a pump piston 28 is assembled into the pump chamber 18 of the housing pump section 14. The pump piston 28 is mounted for reciprocating movement in the pump chamber 18. A trigger 32 is mounted to the housing pump section 14 by a pivot connection (not shown) between the trigger and the pump section. The pivot connection allows the trigger 32 to be manually manipulated or oscillated on the pump section 14. The trigger 32 is operatively connected with the pump piston 28 and causes the pump piston to reciprocate in the pump chamber 18 in response to oscillating movements of the trigger 32 on the pump section 14. As in the operation of conventional trigger sprayers, the manipulation of the trigger 32 and the reciprocation of the pump piston 28 draws liquid from a separate liquid container attached to the trigger sprayer 12 into the pump chamber 18, and dispenses the liquid from the trigger sprayer. A shroud 34 is assembled on the housing pump section 14. The shroud 34 is designed to give the trigger sprayer 12 an aesthetically pleasing appearance to consumers. The housing vent section 16 has a cylindrical wall 36 with a plurality of arcuate ridges 38 projecting outwardly from the wall. The arcuate ridges 38 are designed to mate with the internal ribs 26 of the housing pump section 14 to press fit or snap fit the vent section 16 in the pump section interior. The vent section wall 36 surrounds a hollow interior volume 42 of the housing vent section 16. A liquid supply tube 44 extends through the vent section 16. An upper portion of the tube 44 communicates with the pump chamber 18 when the vent section 16 is assembled into the pump section 14, thereby establishing the liquid supply passage through the trigger sprayer 12. A lower end of the tube 44 communicates with a dip tube (not shown) that extends into the interior of the liquid container to which the trigger sprayer 12 is attached. This communicates the pump chamber 18 with the liquid contained in the liquid container. A circular flange 46 projects outwardly from the bottom of the vent section wall

36. The flange 46 has a circular peripheral edge surface and a flat, annular bottom surface 52 at the bottom of the housing vent section 16. The annular surface 52 surrounds a bottom opening that provides access to the interior 42 of the vent housing section. The housing vent section 16 has a vent wall 54 that is positioned inside the flat annular surface 52. The vent wall 54 has a flat bottom surface. As seen in figure 3, the vent wall 54 projects radially inwardly from the vent section flange 46 and the vent wall surface is coplanar and continuous with the flange annular surface 52. A vent opening 56 extends through the vent wall 54. The vent opening 56 communicates the interior of the container attached to the trigger sprayer 12 with the exterior environment of the trigger sprayer, thus venting the container interior. A membrane 58 is secured to the vent wall 54 covering over the vent opening 56. The membrane 58 is a circular flat disk of a material that is gas permeable and liquid impermeable. Thus, the membrane 58 allows air to pass from the container interior through the membrane and the vent opening 56, but prevents the passage of liquid from the container interior through the membrane and the vent opening. In the preferred embodiment of the invention, the material of the membrane 58 is polytetrafluoroethylene (PTFE). Other equivalent materials may be used for the membrane 58. In the preferred embodiment, the membrane 58 is secured to the surface of the vent wall 54 by being radio frequency (RF) welded to the surface. The membrane 58 could be secured to the surface 54 by other equivalent methods. The housing vent section 16 also comprises a plurality of posts 62 that extend from an interior surface of the vent section 16 through the vent section interior 42. The plurality of posts 62 project outwardly through the bottom opening of the housing vent section 16 and are surrounded by the annular surface 52. As seen in figure 3, the plurality of posts 62 are spaced inwardly from the annular surface 52 and are spatially arranged around the surface. A gasket 64 is secured to the housing vent section 16. The gasket 64 is constructed of typical gasket material, and is constructed as a flat disk having a circular peripheral edge 66. The dimension of the gasket peripheral edge 66 matches the dimension of the vent section circular flange 46. This enables the gasket 64 to cover over and engage against the flat annular surface 52 of the vent section 16. A plurality of holes pass through the gasket. These include a liquid supply hole 68 that is positioned on the gasket to accommodate the dip tube of the trigger sprayer extending through the liquid supply hole 68 and into the liquid in a container attached to the trigger sprayer 12. A vent hole 72 also passes through the gasket 64. The vent hole 72 is positioned on the gasket 64 where the vent hole is positioned over the membrane 52 covering over the vent opening 56 in the vent wall 54. The preferred embodiment of the gasket 64 is also provided with a plurality of post holes 74. The post holes 74 are positioned on the gasket 64 to receive the vent section post 62 and hold the gasket against the annular surface 52 of the housing vent section 16. The liquid supply hole 68, the vent hole 72, and the post holes 74 are all separate from each other and are positioned at relative positions inside the peripheral edge 66 of the gasket 64. The relative positions of the holes positions the liquid supply hole 68 in line with the vent section tube 44, and positions the vent hole 72 in line with the membrane 58 and the vent opening 56 when the vent section posts 62 extend into the gasket post holes 74. The posts 62 extending into the gasket 64 stakes the gasket on the housing vent section annular surface 52 with the membrane 58 positioned between the gasket 64 and the vent wall 54. In an alternate embodiment, the gasket 64 could be provided with only the liquid supply hole 68 and the vent hole 72. This embodiment of the gasket would be staked on the housing vent section 16 by pressing the gasket on the ends of the post 62, thereby staking the gasket on the housing vent section. In either embodiment, the gasket 62 is secured to the housing vent section 16 by the posts 62 extending into post holes 74 in the gasket. A cap 82 having a cylindrical side wall 84 is positioned on the housing vent section 16 prior to its attachment to the housing pump section 14. The cap 82 has an annular lip 86 that rests on top of the housing vent section flange 46, thereby mounting the cap 82 on the vent section 16 for rotation of the cap relative to the vent section. Pressing the vent section 16, with the cap 82 mounted on the section, into the housing pump section 14 interconnects the vent section ridges 38 with the pump section ribs 26. This attaches the housing vent section 16 to the housing pump section 14 with the cap 82 mounted on the housing for rotation of the cap on the trigger sprayer 12. The cap 82 is provided with internal screw threading on the interior surface of the cap sidewall 84 for attaching the trigger sprayer 12 to the neck of a liquid container in the conventional manner. Other means may be provided on the cap 82 for attaching the trigger sprayer 12 to the liquid container. With the trigger sprayer 12 attached to the liquid container, the gasket 16 is positioned to seal between the container neck and the housing vent section annular surface 52. The gasket 64 also seals around the membrane 58 covering the vent opening 56. The posts 62 extending into the gasket 64 secure the gasket in position on the trigger sprayer 12. The novel configurations of the trigger sprayer vent section 16 and gasket 64 provides the trigger sprayer 12 with a passive venting system of simplified and inexpensive construction. The membrane 58 over the vent opening 56 prevents the leakage of liquid from the container through the trigger sprayer, while allowing the venting of air from the exterior environment of the trigger sprayer to the container interior. The coplanar positioning of the vent opening wall 54 and the vent section annular surface 52 enables the same gasket 64 to seal around the vent opening 56 and seal between the trigger sprayer 12 and the liquid container. Thus, the combination of these features provides a trigger sprayer that is economically manufactured, provides a fluid tight seal between the trigger sprayer and the liquid container, and prevents the leakage of liquid from the container while allowing venting of the container.

Claims

What Is Claimed Is 1. A manually operated liquid dispensing apparatus comprising: a housing having a manually operated pump; a liquid supply passage extending through the housing for communicating the pump with a separate liquid container attached to the apparatus; a plurality of posts on the housing; a vent opening on the housing; a gasket that is staked on the housing by the plurality of posts being inserted into the gasket; the gasket having a liquid supply hole with the liquid supply passage extending through the liquid supply hole, and the gasket having a vent hole with the vent opening being positioned in the vent hole; and, a membrane secured to the sprayer housing covering over the vent opening.

2. The apparatus of Claim 1 , further comprising: the membrane being an air permeable, liquid impermeable membrane.

3. The apparatus of Claim 1 , further comprising: the gasket being stacked on the housing by the plurality of posts on the housing extending into a plurality of post holes in the gasket, the plurality of post holes being separate from the liquid supply hole and the vent hole in the gasket.

4. The apparatus of Claim 3, further comprising: the gasket being a flat disk with a circular peripheral edge and the plurality of post holes, the liquid supply hole, and the vent hole are located inside the gasket peripheral edge.

5. The apparatus of Claim 1 , further comprising: the housing having a flat surface that extends around the liquid supply passage and the vent opening; and, the gasket engaging against the flat surface.

6. The apparatus of Claim 1 , further comprising: the housing having a vent wall with the vent opening passing through the vent wall; the membrane being secured to the vent wall over the vent opening; and, the gasket engaging against the vent wall with the membrane positioned between the vent wall and the gasket.

7. A apparatus of Claim 6, further comprising: the vent wall having a flat surface with the vent opening being in the flat surface; the membrane being flat and being secured on the vent wall flat surface; and, the gasket being flat where the gasket engages against the vent wall.

8. A manually operated liquid dispensing apparatus comprising: a housing having a manually operated pump; an annular surface on the housing adapted for connection to a neck of a separate liquid container attached to the apparatus; a liquid supply passage extending through the housing and communicating the pump with a separate liquid container attached to the apparatus; a vent surface on the housing; a vent opening in the vent surface; a gasket engaging against the housing annular surface and the housing vent surface, the gasket having a liquid supply hole with the liquid supply passage extending through the liquid supply hole, and the gasket having a vent hole with the vent opening being positioned in the vent hole; and, a membrane secured to the sprayer housing vent surface covering over the vent opening.

9. The apparatus of Claim 8, further comprising: the membrane being an air permeable, liquid impermeable membrane.

10. The apparatus of Claim 9, further comprising: the housing annular surface and the housing vent surface being coplanar.

11. The apparatus of Claim 10, further comprising: the housing annular surface and the housing vent surface being a single continuous surface.

12. The apparatus of Claim 10, further comprising: a plurality of posts on the housing; and, the gasket being staked on the housing by the plurality of posts on the housing extending into a plurality of post holes formed in the gasket, the plurality of post holes being separate from the liquid supply hole and the vent hole in the gasket.

13. The apparatus of Claim 12, further comprising: the gasket having a peripheral edge and the post holes, the liquid supply hole, and the vent hole all being inside the gasket peripheral edge.

14. The apparatus of Claim 8, further comprising: the gasket engaging against the housing vent surface with the membrane positioned between the vent surface and the gasket.

15. The apparatus of Claim 8, further comprising: the housing annular surface being a flat surface that extends around the liquid supply passage and around the vent surface, and the housing annular surface being coplanar with the vent surface.

16. A manually operated liquid dispensing apparatus comprising: a housing having a manually operated pump; an annular surface on the housing adapted for connection to a neck of a separate liquid container attached to the apparatus; a liquid supply passage extending through the housing and communicating the pump with a separate liquid container attached to the apparatus; a vent surface on the housing, the housing annular surface and the housing vent surface being a single continuous flat surface; a vent opening in the vent surface; and, a gasket engaging around the housing annular surface.

17. The apparatus of Claim 14, further comprising: a membrane secured to the housing vent surface covering over the vent opening.

18. The apparatus of Claim 15, further comprising: the membrane being an air permeable, liquid impermeable membrane.

19. The apparatus of Claim 16, further comprising: the housing annular surface extending completely around the housing vent surface.

20. The apparatus of Claim 16, further comprising: a plurality of posts on the housing; and, the gasket being staked on the housing by the plurality of posts on the housing extending into a plurality of post holes in the gasket, the plurality of post holes being separate from the liquid supply hole and the vent hole.