Glue dispenser and method of using same

Abstract

A glue dispenser includes a low density polyethylene squeeze bottle and a nozzle having a spring loaded ball valve mechanism therein. Between uses, the bottle is stored so the nozzle is below the remainder of the bottle to prevent the glue from drying on the ball valve mechanism. The glue is water-based and has a viscosity in the range of 600-3,000 centipose.

Description

FIELD OF INVENTION

The present invention relates generally to dispensing glue and more particularly to a glue dispenser including a spring loaded valve and to a method of using same.

BACKGROUND ART

There are numerous prior art glue dispensers including spring loaded valves. There are also numerous glue dispensers of the squeeze bottle type. I am unaware, however, of any commercialized glue dispensers having spring loaded valves and squeeze bottle containers.

Prior art glue dispenses frequently have problems dispensing glue in controlled amounts to form spots or dots, as well as to form lines of glue having a desired consistency. Further, prior art glue dispensers having a dispensing mechanism suffer from the problem of glue clogging due to the glue drying on the dispensing mechanism. Such clogging and drying of glue on the dispensing mechanism prevents the dispensing mechanism from working effectively and frequently prevents the dispensing mechanism from working at all.

It is, accordingly, an object of the present invention to provide a new and improved apparatus for dispensing glue.

Another object of the present invention is to provide a new and improved method of using a glue dispenser in such a manner as to prevent clogging and/or drying of the glue against a dispensing mechanism including a spring loaded valve.

A further object of the invention is to provide a new and improved glue dispenser including a spring loaded valve, wherein the dispenser is arranged for enabling the glue to be applied to a workpiece in a very controlled manner, as dots and/or lines.

SUMMARY OF THE INVENTION

One aspect of the present invention relates to the combination of a squeeze bottle carrying liquid glue. The bottle has a squeezable low density polyethylene wall and a liquid dispensing head including a liquid dispensing nozzle normally closed by a spring biased valve member that can be opened to provide a flow of the glue to a workpiece surface in response to the spring biased valve member bearing against the workpiece surface. The glue, bottle and nozzle are arranged so that in response to the bottle wall being squeezed, for example, by a hand of a user, and the valve being pressed against the workpiece surface, the glue flows through the nozzle onto a portion of the workpiece surface being contacted by the valve. The glue flowing through the nozzle stays substantially in situ under ambient room temperature and pressure conditions.

A further aspect of the invention relates to a bottle carrying liquid glue. The bottle has a liquid dispensing head including a liquid dispensing nozzle normally closed by a spring biased valve member that can be opened to provide a flow of the glue to a workpiece surface in response to the spring biased valve member bearing against the workpiece surface. The glue, bottle and nozzle are arranged so that in response to the valve being pressed against the workpiece, the glue flows through the nozzle onto the workpiece portion contacting the valve. A holder for the bottle and the bottle are dimensioned and arranged so the valve is closed and the glue bears against the valve while the bottle is in the holder to prevent drying of the glue on the valve passages and parts, whereby clogging of the passages and parts is obviated.

A further aspect of the invention relates to a squeeze bottle carrying a liquid glue. The bottle has a squeezable wall and a liquid dispensing head including a liquid dispensing nozzle normally closed by a spring biased valve member that can be opened to provide flow of the glue to a workpiece surface in response to the spring biased valve member bearing against the workpiece surface. The glue, bottle and nozzle are arranged so that in response to the bottle wall being squeezed and the valve being pressed against the workpiece, the glue flows through the nozzle onto the workpiece portion contacting the valve and stays substantially in situ under ambient room temperature and pressure conditions. The valve includes a sphere and a compression spring having one end bearing against a surface of the sphere. The nozzle includes a passage ending at an end face of the nozzle. The passage has an end with a circular cross section in which the sphere is located. The end of the passage at the end face is circular. The sphere and the passage at the end face are dimensioned and shaped such that the sphere projects beyond an end face of the nozzle while the valve is closed, with the projection being through a distance slightly less (about 90%) than the radius of the sphere. It was found through actual experimentation that such a distance provides optimum dispensing of the glue on the workpiece, as spots and/or lines.

Preferably the glue is water-based and has a viscosity in the range of 600-3,000 centipose, and preferably in the range of 800-1,200 centipose. I have found that glues having viscosity less than 600 centipose do not adequately stay in situ on the workpiece, when dispensed through a spring biased valve member. I have also found that glues having a viscosity greater than 3,000 centipose do not flow adequately through the spring biased valve member. I have found that glues having viscosities in the range of 800-1,200 centipose provide the best flow characteristics and satisfactorily remain in situ on the workpiece. Typically, the glue is applied to the workpiece in spots, by pressing the nozzle to the workpiece and holding the valve member against the spot. I have also found that the glue can be applied as lines to a workpiece, by pressing the spring biased valve member against the workpiece and moving the valve along the workpiece.

A further aspect of the invention relates to a method of storing and dispensing glue in a dispensing container including a spring biased valve member in a dispensing nozzle. The method comprises preventing the glue from drying around the valve and spring and in the nozzle between dispensing operations by storing the dispensing container in a position so that the valve, nozzle and spring are below the remainder of the container and are covered by the glue. The glue in the container is dispensed onto a workpiece by pushing the valve against the workpiece.

Preferably, the dispensing step includes dispensing the glue onto a portion of the workpiece by pressing the valve member against the workpiece portion while causing a force component to be exerted on the glue toward the nozzle and the workpiece portion. The force component is exerted by gravity in response to the nozzle being held below the remainder of the container and/or is exerted by squeezing a squeezable container in which the glue is located.

I have found, through actual experimentation, that the glue is prevented from clogging and drying around the valve, spring and in the nozzle between dispensing operations by storing the dispensing container so that the valve, nozzle and spring are below the remainder of the container and are covered by the glue. I believe drying is prevented because air in the glue forms bubbles that rise in the liquid glue.

I have found the combination of the squeeze bottle having a squeezable low density polyethylene wall and the combination of a spring biased valve member provide extremely good control over the flow of the liquid glue to a workpiece. This is particularly true for liquid, water-based resin glue having a viscosity in the range of 600-3,000 centipose. I have also found the combination of a bottle with low density polyethylene wall, the water-based resin glue and a spherical valve that extends beyond an end face of the nozzle by a distance that is slightly less than the radius of the spherical valve assist in providing the desired control.

The above and still further objects, features and advantages of the present invention will become apparent upon consideration of the following detailed description of one specific embodiment thereof, especially when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective view of a preferred embodiment of a liquid glue dispenser in accordance with the invention;

FIG. 2 is a side view of the dispenser illustrated in FIG. 1;

FIG. 3 is a side view of the dispenser, with the dispensing head removed from the dispenser;

FIG. 3A is a bottom view of the dispenser of FIGS. 1-3;

FIG. 4 is a cross sectional view of the dispensing head of the dispenser of FIGS. 1-3;

FIG. 5 is a cross sectional view of the dispensing head of the dispenser of FIGS. 1-4, in a holder for the dispenser, in combination with the portion of a bottle of the dispenser connected to the head;

FIG. 6 is an exploded view of the dispenser head and one end of the dispenser of FIGS. 1-5; and

FIG. 7 is a view of the device illustrated in FIGS. 1-6 in use, wherein the bottle of the dispenser is gripped by a hand to apply a spot of glue to a workpiece, wherein the spot of glue is spaced from a line of glue on the workpiece that has been previously applied.

DETAILED DESCRIPTION OF THE DRAWING

Reference is now made to the drawing, wherein glue dispenser (10) is illustrated as including glue dispensing nozzle assembly (11), connected to one end of elongated container (12). During use, glue in container (12) is dispensed through a spring biased valve of nozzle assembly (11) onto a workpiece, to form spots of glue on the workpiece and/or lines of glue on the workpiece. Between uses, dispenser (10) is placed on holder (13) so that nozzle assembly (11) is below container (12). Consequently, the glue fills and wets the passages and valve mechanism of nozzle assembly (11), to prevent drying and clogging of glue in the passages and valve mechanism of nozzle assembly (11). Actual experimentation and use indicates that storing dispenser (10) in holder (13) so that nozzle assembly (11) is below container (12) prevents drying of glue in the passages and the mechanism of the valve assembly, to prevent clogging of the glue in the passages and valve assembly. To remind the user to keep the nozzle assembly (11) below container (12), the container includes human readable indicia, such as an arrow, or a written message to this effect; the indicia in FIG. 2 are written and include the legend “Keep nozzle in stand to prevent clogging.”

Container (12) is a one piece molded structure made of low density polyethylene, i.e., polyethylene having a density in the range of about 0.915-0.925 grams per cubic centimeter. Low density polyethylene has a density less than a 1:1 mixture of ethanol and water and is a branched polymer having molecules packed more loosely than those of high density polyethylene. Low density polyethylene is more transparent and waxy than high density polymer and is known to be used to make flexible bottles.

Container (12) holds a mass (9) of water based resin emulsion liquid adhesive, preferably having a solid content of approximately 60% by weight, a viscosity in the range of 600-3,000 centipose and a density of about 1.1. A viscosity in excess of 3,000 centipose for glue mass (9) results in the glue flowing too slowly from container (12) through nozzle assembly (11) onto a workpiece. If the viscosity of the mass of glue (9) is less than about 600 centipose, the glue flows too quickly from container (12) through nozzle assembly (11). Hence, if the glue viscosity is outside the stated range, it is difficult to control application of the glue to the workpiece, to form spots and/or lines of glue on the workpiece. Through actual experimentation, I have found that optimum results occur if the viscosity of the glue in container (12) is approximately 1,000 centipose, i.e., in a range between approximately 800-1,200 centipose.

Container (12) has a manually squeezable tubular wall (14) having circular inner and outer diameters coaxial with longitudinal axis (15) of container (12). At a first end of wall (14) is a planar rigid “base” (16), including ribs (18) that prevent substantial deflection of the base in response to manual squeezing of wall (14). At a second, opposite end of wall (14) is collar (20), from which extends tubular neck (22) that is coaxial with axis (15) and includes circular inner and outer diameters. The exterior wall of neck (22) includes threads (24) for mating with corresponding threads (26) on the interior of circular flange (28) of cast stainless steel, one piece cap (30), that is part of nozzle assembly (11). The threads (24) and (26) respectively on neck (22) and flange (28) enable cap (30) to be easily connected to and removed from container (12). To facilitate manual insertion and removal of cap (30) from container (12), the exterior of flange (18) includes knurling (31).

The closed end of flange (28), i.e., the end opposite from the open end of the flange, is screwed into neck (22). Cap (30) includes disc (33), including planar face (32) having a central bore (34), centered on axis (15), with which flange (28) and neck (22) are coaxial. Shoulder (36) extends from the exterior face of one piece stainless steel disc (33) and stub-cylinder (38) extends from shoulder (36). Bore (34) extends through shoulder (36) and cylinder (38), as well as disc (33), to form part of a passage for glue that flows from container (12) to the workpiece. Cylinder (38) has on its exterior surface threads (40) that mesh with corresponding threads on the interior of bore (46) of cast stainless steel nozzle (42). Nozzle (42) includes tube (44) and end disk (45). Tube (44) has an exterior wall (50) having a hexagonal cross section for facilitating manual screwing of tube (44) onto threads (40) of cylinder (38).

Aluminum sleeve (48) is bonded to the end of bore (46) opposite from shoulder (36) so the end of the sleeve abuts interior wall (50) of disk (45). The end of sleeve (48) opposite from exterior wall (50) of disk (45) is bonded to the portion of bore (46) immediately past the end region of the threads in the bore.

Inserted into bore (46) and sleeve (48) are cylindrical, coiled, stainless steel spring (56) and stainless steel sphere (58) that functions as a ball valve to open and close the passage in disk (45) formed by central bore 60 in the disk. Opposite first and second ends of spring (56) bear against sphere (58) and edge (64) of cylinder (38) that is remote from shoulder (36). The diameters of sphere (58) and bore (60), and the length of bore (60) are such that the sphere extends by slightly less than the radius of the sphere (58) beyond outer face (62) when sphere (58) closes the passage formed by bore (60). In one particular embodiment, the extent of sphere (58) beyond outer face (62) was approximately 0.88 times the radius of the sphere. In this embodiment, the diameter of bore (60) is 0.98 times the diameter of the sphere and the length of bore (60) is ⅙ the diameter of the sphere.

To positively prevent leakage of glue from container (12) through the connection of nozzle assembly (11), neoprene gasket (66) is placed in cap (30), against planar face (32), such that the perimeter of the gasket engages the interior side wall of flange (28) that carries the threads (26).

Holder (13) includes well (68), dimensioned to receive tube (44), with sphere (58) projecting from the end of the tube. Hence, well (68) has a length in excess of the length of tube (44) and the well has a diameter somewhat in excess of the distances separating a pair of opposite, parallel sides of tube (44). At the top part of holder (13) is circular, upper face (70), having a diameter somewhat greater than the diameter of base (16) and collar (20); the diameter of circular upper face (70) is the same as the diameter of exterior wall (72) of holder (13). Holder (13) includes shoulder (74), at the top of well (68). Shoulder (74) has a diameter slightly in excess of the outer diameter of flange (28), for receiving the exterior, outer circular face of shoulder (36). Holder (13) includes a vertical wall between face (70) and shoulder (74).

Dispenser (10) is placed in holder (13) so that the glue in container (12) bears against the portion of sphere (58) in sleeve (48). The glue also bears against all surfaces of sleeve (48) that are not in contact with tube (44) and the interior surfaces of tube (44) that are not covered by sleeve (48). The glue also bears against cylindrical, compression coil spring (56) and all interior surfaces of cap (30). Because all interior surfaces of nozzle assembly (11) are wetted by the glue, the glue does not have an opportunity to dry on these surfaces and clogging of the glue in the passages and against the parts of the nozzle assembly (11) does not occur.

In use, dispenser (10) is typically lifted from holder (13) and ball valve (58) is pressed downwardly against a workpiece, as illustrated in FIG. 7, causing glue to flow from container (12) through passages including bores (34), (46) and (60), and between the outer surface of sphere (58) and the resulting opening between the sphere and bore (60) at the end of the bore concident with face (62). If it is desired to form a spot or dot of glue on the workpiece, container (12) is held stationary by a user, who presses against wall (14). Thereby, the force of gravity, as well as the force exerted against wall (14), causes the glue to flow onto the spot. Alternatively, if it is desired to draw a line of glue on a workpiece, the user moves container (12) while (1) holding ball valve (18) downwardly against the workpiece, (2) pressing against wall (14) and (3) moving container (12) in the path of the line to be drawn. Usually, it is desirable for the force of gravity to be combined with the force exerted by the user squeezing wall (14). However, in some instances, the glue can be applied to surfaces which are horizontally disposed, in which case the force of gravity does not affect the dispensing of glue from container (12) onto the workpiece. In such instances, however, it is usually necessary to exert greater force on wall (14) of container (12).

In one actually constructed embodiment including low density polyethylene container (12) and water based resin glue having a viscosity of approximately 2,000 centipose, wall (14) had an outer diameter of approximately 2″, a wall thickness of approximately 1/16 of an inch, and a height of approximately 5″. In this embodiment, sphere (58) had a diameter of ⅜″, and bores (34), (46) and (60) had diameters of approximately 5/64″, 7/16″ and 11/64″, sleeve (48) had an inner diameter of 7/32″ and bore (60) had a length of approximately 1/16″. It was found that these dimensions, in combination with the described glue and described squeeze bottle, enabled glue in the container (12) to be dispensed evenly, in a controlled manner against a workpiece, by pressing sphere (58) downwardly against the workpiece, while squeezing wall (14). The glue stayed substantially in situ on the workpiece surface contacted by ball valve (58) under ambient temperature (72° F.) and pressure (30.00 inches of mercury) conditions.

While there has been described and illustrated one embodiment of the invention, it will be clear that variations in the details of the embodiment specifically illustrated and described may be made without departing from the true spirit and scope of the invention as defined in the appended claims.

Claims

1. In combination; a squeeze bottle carrying liquid glue, the bottle having a squeezable low density polyethylene wall and a liquid dispensing head including a liquid dispensing nozzle normally closed by a spring biased valve member that can be opened to provide a flow of the glue to a workpiece surface in response to the member bearing against the workpiece surface; the glue, bottle and nozzle being arranged so that in response to the bottle wall being squeezed and the valve being pressed against the workpiece surface, the glue flows through the nozzle onto a portion of the workpiece surface being contacted by the valve and stays substantially in situ under ambient room temperature and pressure conditions.

2. The combination of claim 1, wherein the valve comprises a sphere and a spiral, coiled compression spring having one end bearing against a surface of the sphere.

3. The combination of claim 2, wherein the nozzle includes a passage ending at an end face of the nozzle, the passage having an end with a circular cross-section in which the sphere is located; the sphere and the passage at its end being dimensioned and shaped such that the sphere projects beyond the end of the passage while the valve is closed by a distance that is slightly less than the radius of the sphere.

4. The combination of claim 3, wherein the glue is water-based and has a viscosity in the range of 600-3000 centipose.

5. The combination of claim 4, wherein the viscosity is in the range of 800 to 1,200 centipose.

6. The combination of claim 1, wherein the glue is water-based and has a viscosity in the range of 600-3000 centipose.

7. The combination of claim 6, wherein the viscosity is in the range of 800 to 1,200 centipose.

8. The combination of claim 1, further including a holder for holding the bottle, the holder of the bottle being dimensioned and arranged so the valve is closed and the glue bears against the valve while the bottle is in the holder.

9. In combination, a bottle carrying liquid glue, the bottle having a liquid dispensing head including a liquid dispensing nozzle normally closed by a spring biased valve member that can be opened to provide a flow of the glue to a workpiece surface in response to the member bearing against the workpiece surface; the glue, bottle and nozzle being arranged so that in response to the valve being pressed against the workpiece surface, the glue flows through the nozzle onto the workpiece portion contacting the valve; a holder for holding the bottle, the holder and the bottle being dimensioned and arranged so the valve is closed and the glue bears against the valve and valve parts while the bottle is in the holder whereby air does not contact the valve and valve parts while the bottle is in the holder.

10. The combination of claim 9, wherein the bottle is a squeeze bottle having a wall that can be manually squeezed, the wall, glue and nozzle being such that in response to manual squeezing of the wall, the glue flows through the nozzle onto a portion of the workpiece surface being contacted by the valve and stays substantially in situ under ambient room temperature and pressure conditions.

11. The combination of claim 9, wherein the valve comprises a sphere, and the spring comprises a coiled compression spring having one end bearing against a surface of the sphere.

12. The combination of claim 11, wherein the nozzle includes a passage ending at an end face of the nozzle, the passage having an end with a circular cross-section in which the sphere is located; the sphere and the passage at its end being dimensioned and shaped such that the sphere projects beyond the end of the passage while the valve is closed by a distance that is slightly less than the radius of the sphere.

13. In combination, a squeeze bottle carrying liquid glue, the bottle having a squeezable wall and a liquid dispensing head including a liquid dispensing nozzle normally closed by a spring biased valve member that can be opened to provide a flow of the glue to a workpiece surface in response to the member bearing against the workpiece surface; the glue, bottle and nozzle being arranged so that in response to the bottle wall being squeezed and the valve being pressed against the workpiece, the glue flows through the nozzle onto the workpiece portion contacting the valve and stays substantially in situ under ambient room temperature and pressure conditions, the valve including a sphere and a spring, the spring comprising a coiled compression spring having one end bearing against a surface of the sphere, the nozzle including a passage ending at an end face of the nozzle, the passage having an end with a circular cross-section in which the sphere is located; the sphere and the passage at its end being dimensioned and shaped such that the sphere projects beyond the end of the passage while the valve is closed by a distance that is slightly less than the radius of the sphere.

14. The combination of claim 13, wherein the glue is water-based and has a viscosity in the range of 600-3000 centipose.

15. The combination of claim 13, further including a holder for holding the bottle, the holder of the bottle being dimensioned and arranged so the valve is closed and the glue bears against the valve while the bottle is in the holder.

16. The combination of claim 13 wherein the wall is made of low density polyethylene.

17. A method of storing and dispensing glue in a dispensing container including a spring biased valve in a dispensing nozzle,

the method comprising:

preventing the glue from drying around the valve, spring and in the nozzle between dispensing operations by storing the dispensing container in a position so that the valve, nozzle and spring are below the remainder of the container and are covered by the glue, and

dispensing the glue in the container onto a workpiece by pushing the valve against the workpiece.

18. The method of claim 17 wherein the dispensing step includes dispensing the glue onto a portion of the workpiece by pressing the valve against the workpiece portion while causing a force component to be exerted on the glue toward the nozzle and the workpiece portion.

19. The method of claim 18 wherein the force component is exerted by gravity in response to the nozzle being held below the remainder of the container.

20. The method of claim 18 wherein the container is squeezable and the force component is exerted by squeezing the container.

21. The method of claim 18 wherein the portion of the workpiece is a spot on the workpiece and the valve is held stationary at the spot while the valve is being pressed against the spot.

22. The method of claim 18 wherein the portion of the workpiece is a line on the workpiece and the valve is moved along the line while the valve is being pressed against the line.

23. In combination; a container carrying liquid glue, the container having a wall and a liquid dispensing head including a liquid dispensing nozzle normally closed by a spring biased valve member that can be opened to provide a flow of the glue to a workpiece surface in response to the member bearing against the workpiece surface; the glue, container and nozzle being arranged so that in response to the valve being pressed against the workpiece surface, the glue flows through the nozzle onto a portion of the workpiece surface being contacted by the valve, the container including human readable indicia advising a user to keep the nozzle below the container.