# Patent

## Title
Locking aerosol spray tube

## Abstract

A modified spray cap and extension tube. Positive mechanical interlocking features are added which lock the extension tube to the cap. The extension tube therefore does not fly out of the cap when in use. The modified spray cap is configured so that a conventional diffused spray pattern is still achieved when the modified extension tube is removed.

## Background
CROSS-REFERENCES TO RELATED APPLICATIONS
This is a continuation-in-part application of U.S. application Ser. No. 10/410,983, filed Apr. 10, 2003 now U.S. Pat. No. 6,783,037.
MICROFICHE APPENDIX
Not Applicable


STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
Not Applicable


BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the field of aerosol spray cans. More specifically, the invention comprises a revised extension tube that locks to the spray cap when in use.
2. Description of the Related Art
Aerosol spray cans tend to deliver a diffused spray. In some applications, such as the precise deposition of lubricants, this diffused pattern is undesirable. Where precise application is needed, an extension tube has customarily been used.
FIG. 1 shows a prior art aerosol can 10. To dispense its contents, the user pressed down on spray cap 12. A diffused spray pattern then issues from orifice 16. Extension tube 18, which is simply a long hollow piece of plastic, can be inserted into orifice 16. In some prior art devices, orifice 16 is contained within nozzle insert 14. Gripping features, such as small ribs or pliable materials, can be included within nozzle insert 14. These help frictionally retain the portion of extension tube 18 that is thrust into orifice 16. However, those skilled in the art will know that this frictional retention approach is only marginally effective. The contents of aerosol can 10 issue forth under considerable pressure. They may also have significant lubricating value. These two factors degrade the prior art devices' ability to retain extension tube 18 in position. In fact, it is not uncommon for an extension tube 18 to be launched out of spray cap 12 like a projectile.
BRIEF SUMMARY OF THE INVENTION
The present invention comprises a modified spray cap and extension tube. Positive mechanical interlocking features are added which lock the extension tube to the cap. The extension tube therefore does not fly out of the cap when in use. The modified spray cap is configured so that a conventional diffused spray pattern is still achieved when the modified extension tube is removed.



BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
FIG. 1 is an isometric view, showing a prior art spray cap and extension tube.
FIG. 2 is an isometric view, showing a modified spray cap and extension tube.
FIG. 3 is an isometric sectional view, showing the internal features of the modified spray cap.
FIG. 4 is a hidden line view, showing the modified extension tube.
FIG. 5 is an isometric view, showing an alternate embodiment of the modified extension tube.
FIG. 5B is an isometric view, showing an alternate embodiment of the modified spray cap.
FIG. 6 is an isometric view, showing the modified extension tube locked into the modified spray cap.
FIG. 7 is an isometric sectional view, showing an alternate embodiment of the present invention.
FIG. 8 is an isometric sectional view, showing an alternate embodiment of the present invention.
FIG. 9A is a hidden line view, showing an alternative embodiment of the modified spray cap.
FIG. 9B is a hidden line view, showing an alternative embodiment of the modified spray cap.
FIG. 10 is a hidden line view, showing an alternative embodiment of the modified spray tube.
FIG. 11 is an isometric view, showing the modified extension tube locked into the modified spray cap.



REFERENCE NUMERALS IN THE DRAWINGS


















10
aerosol can
12
spray cap



14
nozzle insert
16
orifice



18
extension tube
20
T-cap



22
cross slot
24
T-tube



26
conduit
28
orifice



30
locking block
32
first mating surface



34
second mating surface
36
inlet



38
tube
40
gasket insert



42
threaded cap
44
threaded counterbore



46
threaded tube
48
threaded shank



50
threaded extension
52
delivery tube



54
spray slot
56
boss



58
extension tabs
60
tube tabs



62
mating surface
64
inclined surface



66
inclined surface
68
detent



70
mating surface
72
ridge










DETAILED DESCRIPTION OF THE INVENTION
FIG. 2 shows T-cap 20 and T-tube 24. T-cap 20 generally assumes the same shape as prior art spray cap 12. However, a pair of intersecting slots are cut into its upper surface. These are cross slot 22 and spray slot 54. These two slots combine to form a “T” shape, hence the name T-cap 20. A modified type of extension tube is configured to mechanically interlock with the two slots. The view shows T-tube 24 in position to be installed.
FIG. 3 shows T-cap 20 sectioned in half. It is shown just above the position it would normally occupy when installed on aerosol can 10. Although the particular method of installing T-cap 20 on aerosol can 10 is not significant to the present invention, those skilled in the art will know that one good method of installing such a cap is to press the lower portion of conduit 26 over delivery tube 52.
Delivery tube 52 remains in aerosol can 10. When it is pressed downward, the contents of the can are delivered through the hollow interior of delivery tube 52. When T-cap 20 is installed, the can's contents are delivered through conduit 26, eventually emerging through orifice 28. Orifice 28 is actually located in the rear wall of cross slot 22, which is designated as first mating surface 32 in FIG. 3.
The reader will observe that spray slot 54 is aligned with orifice 28. This fact is significant since the device preferably functions well without the use of an extension tube. In other words, the user preferably has the option of a diffused spray available without an extension tube, or a focused spray available with the extension tube. To that end, the side walls of spray slot 54 preferably diverge somewhat so as not to interfere with the spray pattern when T-tube 24 is not in use.
FIG. 4 shows the portion of T-tube 24 which is configured to lock into T-cap 20 in more detail. Locking block 30 is a rectangular piece which is attached to the hollow tube 38. Inlet 36 is located on second mating surface 34. It passes through locking block 30 to connect with the hollow interior of tube 38. The reader will observe by studying the geometry that when T-tube 24 is pressed into T-cap 20, second mating surface 34 will mate snugly with first mating surface 32 (assuming that locking block 30 is properly sized with respect to cross slot 22). The height of locking block 30 is selected so that when its lower surface mates against the lower surface of cross slot 22, inlet 36 will be aligned with orifice 28. Tube 38 will then lie within spray slot 54.
Second mating surface 34 bears against first mating surface 32 so that when the user presses T-cap 20, the contents of aerosol can 10 will flow from orifice 28 into inlet 36 without unwanted leakage. However, for certain low-viscosity solvents, the mating of the two surfaces alone maybe insufficient. FIG. 5 shows the addition of gasket insert 40 to second mating surface 34. Gasket insert 40 is preferably made of a pliable sealing material which helps form a tight seal between orifice 28 and inlet 36. A sealing gasket can also be placed on T-cap 20. FIG. 5B shows an alternate version of T-cap 20 in which a gasket insert 40 has been added around orifice 28.
FIG. 6 shows the completed assembly, with T-tube 24 mechanically locked to T-cap 20. The reader will observe how locking block 30 rests within cross slot 22 and how tube 38 rests within spray slot 54. In this configuration, the user may freely employ tube 38 without fear of it coming loose from T-cap 20. The user is also free to use the can with a more conventional diffused spray by simply removing T-tube 24. It easily presses into place and it is just as easily removed.
FIG. 7 shows other mechanical interlocking means which can be used to lock the extension tube to the cap. Conduit 26 passes through threaded cap 42, bends 90 degrees, and exits at a point on the cap's perimeter. Threaded counterbore 44 is provided at this point of exit. Threaded tube 46 is substituted for T-tube 24. It has threaded shank 48, which features a male thread sized to engage the female thread within threaded counterbore 44. Inlet 36 passes through threaded shank 48 and connects to the hollow interior of the extension tube. In this embodiment, the user installs the extension tube by threading threaded shank 48 into threaded counterbore 44, and removes it by unthreading threaded shank 48 from threaded counterbore 44. Both components are shown sectioned in half in order to aid visualization.
An alternate embodiment is shown in FIG. 8. Threaded extension 50 extends from the cap's perimeter at the point where conduit 26 exits. Threaded extension 50 features a male thread. An alternate embodiment of threaded tube 46 is also provided. In the version shown in FIG. 8, threaded shank 48 features a female thread along the wall of inlet 36. This female thread is sized to engage the male thread on threaded extension 50. Its operation is the same as for the embodiment shown in FIG. 7; i.e., the user installs and removes the extension tube using the threaded engagement.
FIG. 9A, FIG. 9B, FIG. 10, and FIG. 11 show another embodiment of the present invention. An alternative embodiment of threaded extension 50 and threaded shank 48 is also provided. FIG. 9A shows threaded cap 42 with an alternate embodiment of threaded extension 50. Boss 56 is affixed to threaded cap 42 around conduit 26. Threaded extension 50 protrudes from boss 56 at the point where conduit 26 exits. Threaded extension 50 features extension tabs 58 which resemble partial turns of threading on opposite sides of threaded extension 50. Extension tabs 58 feature inclined surface 64 on the side proximal to boss 56.
FIG. 9B illustrates inclined surface 64 on extension tabs 58 from a different perspective. Inclined surface 64 features ridge 72 which allows extension tabs 58 to “lock” into place with the spray tube when the two are rotationally engaged.
FIG. 10 shows threaded tube 46 with an alternate embodiment of threaded shank 48. Inlet 36 is sized to receive threaded extension 50 of FIG. 9A. Tube tabs 60 are sized and positioned within inlet 36 to engage extension tabs 58 when threaded cap 42 and threaded tube 46 are threadedly connected as shown in FIG. 11. Tube tabs 60 have inclined surface 66 that mates with inclined surface 64 when tube tabs 60 and extension tabs 58 are rotationally engaged. Inclined surface 66 is distal to mating surface 70 so that rotational engagement of tube tabs 60 and extension tabs 58 forces mating surface 70 against mating surface 62. Tube tabs 60 also feature detent 68 at the peak of inclined surface 66, thereby allowing ridge 72 of extension tabs 58 to snap into place. Once the ridges 72 are snapped into the detents 68, the threaded tube is held securely in place.
FIG. 11 illustrates the attachment of threaded tube 46 to threaded cap 42. To attach threaded tube 46 and threaded cap 42, threaded extension 50 is inserted into inlet 36 of threaded shank 48 so that mating surface 70 abuts mating surface 62. Threaded shank 48 is then rotated approximately a quarter of a turn in the clockwise direction relative to boss 56, thereby engaging extension tabs 58 with tube tabs 60. To release threaded tube 46 from threaded cap 42, threaded shank 48 is rotated approximately a quarter of a turn in the counterclockwise direction relative to boss 56.
The preceding description contains significant detail regarding the novel aspects of the present invention. It is should not be construed, however, as limiting the scope of the invention but rather as providing illustrations of the preferred embodiments of the invention. As an example, many shapes could be employed for cross slot 22, spray slot 54 and locking block 30. They are not limited to the orthogonal walls shown, but could instead be elliptical in shape. Such a variation would not alter the function of the invention. Thus, the scope of the invention should be fixed by the following claims, rather than by the examples given.

## Claims

1. A locking extension tube assembly allowing a user to lock an extension tube to an aerosol spray can, wherein said aerosol spray can includes a delivery tube which, when pushed downward, delivers the contents of said aerosol spray can therethrough, comprising:
a. a cap, having an upper portion, an outer perimeter, and a lower portion positioned over said delivery tube;
b. an extension, protruding from said outer perimeter of said cap, said extension having a cylindrical external surface around a center axis, a first end, and a second end, said second end distal to said outer perimeter of said cap;
c. a conduit, beginning at said lower portion of said cap directly over said delivery tube and ending at an orifice proximal to said second end of said extension;
d. a tab, connected to said extension and projecting from said extension, said tab substantially perpendicular to said center axis of said extension;
e. a spray tube, having an inlet adapted for attaching to said extension and said tab when said extension and said spray tube are insertedly situated and said inlet is rotated about said center axis of said extension;
f. a boss attached to said extension proximal to said cap, said boss having a tube mating surface facing said tab of said extension;
g. a boss mating surface on said spray tube, said boss mating surface proximal to said inlet of said spray tube; and
h. wherein said tube mating surface of said boss mates with the boss mating surface of said spray tube when said inlet is rotated about said center axis of said extension.

2. The locking extension tube assembly of claim 1, said tab further comprising an inclined surface facing said cap.

3. The locking extension tube assembly of claim 1, said spray tube further comprising a tube tab disposed within said inlet of said spray tube and projecting inward into said spray tube, said tube tab configured to releasably attach to said tab of said extension when said extension and said tab are together inserted into said inlet of said spray tube and said inlet is rotated about said center axis of said extension.

4. The locking extension tube assembly of claim 1, said tab further comprising a first surface facing said cap and a ridge on said first surface protruding toward said cap.

5. The locking extension tube assembly of claim 4, said spray tube further comprising a tube tab disposed within said inlet of said spray tube and projecting inward into said spray tube, said tube tab having a ridge valley configured to engage said ridge of said tab of said extension when said extension and said tab are together inserted into said inlet of said spray tube and said inlet is rotated about said center axis of said extension.

6. The locking extension tube assembly of claim 1, wherein said tab projects outward from said external surface of said extension.

7. The locking extension tube assembly of claim 1, wherein said inlet of said spray tube is adapted for receiving and attaching to said extension and said tab when said extension and said tab are together inserted into said inlet of said spray tube and said inlet is rotated about said center axis of said extension.

8. A locking extension tube assembly allowing a user to lock an extension tube to an aerosol spray can, wherein said aerosol spray can includes a delivery tube which, when pushed downward, delivers the contents of said aerosol spray can therethrough, comprising:
a. a cap, having an upper portion, an outer perimeter, and a lower portion positioned over said delivery tube, including
i. an extension, having a cylindrical external surface and a center axis running the length of said extension, said extension protruding out from said outer perimeter, said extension including a tab on and projecting outwardly from said external surface,
ii. a conduit, beginning at said lower portion of said cap directly over said delivery tube and ending in an orifice in said extension;
iii. a boss attached to said extension proximal to said cap, said boss having a tube mating surface facing said tab of said extension;

b. a spray tube, including
i. a shank, having a substantially hollow interior;
ii. a tube, having a hollow interior, attached to said shank;
iii. an inlet passing through said shank and connecting with said hollow interior of said tube;
iv a tube tab disposed from said interior of said shank, said tube tab projecting inward into said substantially hollow interior; and
v. wherein said inlet and said tube tab are adapted for receiving and attaching to said extension and said tab of said extension when said extension and said tab are together inserted into said inlet of said spray tube and said inlet is rotated about said center axis of said extension.

9. The locking extension tube assembly of claim 8, wherein said spray tube removably attaches to said cap when said inlet of said spray tube is rotated a quarter of a turn with respect to the center axis of said extension.

10. The locking extension tube assembly of claim 8, said tab of said extension further comprising an inclined surface facing said cap.

11. The locking extension tube assembly of claim 8, said tab further comprising a first surface facing said cap and a ridge on said first surface protruding outwardly from said first surface toward said cap.