Title:
Automatic umbrella
Kind Code:
A1


Abstract:
An automatic umbrella has an electric motor, nose, and gear assembly which rides up or down the interior of the handle/body of the umbrella on threading/gearing on the interior of the umbrella shaft. As the traveler assembly rises the ribs hingedly connected to the traveler extend through notches or slots in the end of the umbrella, until the nose extends out the end and the ribs actually swing downwards. Motion of the ribs is controlled by a pin or guide on the side of the notch which cooperates with the shaped sides of the umbrella ribs. The nose acts to tension the canopy in the deployed position. The traveler may move due to a rotating gear engaging the threaded inside surface of a tubular body, or the tubular body may be rotated (preferably within an outer housing) and the traveler forced upward by the motion.



Inventors:
Ham, Demetrius Calvin (Dingmans Ferry, PA, US)
Application Number:
12/156054
Publication Date:
12/03/2009
Filing Date:
05/29/2008
Primary Class:
Other Classes:
135/16
International Classes:
A45B25/16
View Patent Images:
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20030098053Canopy structure for play yardMay, 2003Huang
20080053505PORTABLE GARAGEMarch, 2008Ampoyo
20030056817Canopy apparatusMarch, 2003Miller et al.
20020078985MIST-PRODUCING UMBRELLA DEVICEJune, 2002Farr
20080314427Protective play enclosureDecember, 2008Lai
20080121261Portable painting tentMay, 2008Bauer
20070272289Water exclusion system for a tentNovember, 2007Cooper



Primary Examiner:
YIP, WINNIE S
Attorney, Agent or Firm:
Demetrius, Ham C. (10 Woodridge Ct, Newton, NJ, 07860, US)
Claims:
What is claimed is:

1. An umbrella comprising: an elongated handle having an elongated interior space therein, the elongated handle being internally threaded and having upper and lower ends; a traveler disposed within the elongated interior space, the traveler having an electric motor operatively connected to a gear, the gear being disposed in operative engagement with the internal threading of the elongated handle; a plurality of ribs secured to the traveler in a hinged fashion, the plurality of ribs extending from the traveler in the direction of the upper end of the elongated handle; and a canopy attached to the plurality of ribs.

2. The umbrella of claim 1, further comprising: a battery in operative electrical connection with the electric motor.

3. The umbrella of claim 1, where in the traveler further comprises: a nose at the upper end of the traveler.

4. The umbrella of claim 3, wherein the nose further comprises: a plurality of nose grooves aligned with the plurality of ribs and as deep as the ribs.

5. The umbrella of claim 1, further comprising: a plurality of apertures at the upper end of the elongated handle, the apertures aligned with the plurality of ribs, the ribs passing through respective apertures.

6. The umbrella of claim 5, wherein the plurality of apertures further comprise: a plurality of notches.

7. The umbrella of claim 5, wherein the plurality of apertures further comprise: a plurality of guides disposed in the plurality of apertures and operatively engaged to the respective ribs passing therethrough.

8. The umbrella of claim 7, wherein the plurality of ribs further comprise: shaped sides, the plurality of guides operatively engaged to the respective ribs at the shaped sides.

9. The umbrella of claim 1, further comprising: a control having three positions, a first position in which no electrical current is supplied to the electrical motor, a second position in which a first polarity electrical current is supplied to the electrical motor, and a third position in which a reversed second polarity electrical current is supplied to the electrical motor.

10. The umbrella of claim 3, wherein the nose of the traveler projects from the upper end of the traveler and contacts and tensions the canopy when the traveler is in a first position.

11. An umbrella comprising: an elongated handle having an elongated interior space therein, the elongated handle having upper and lower ends, the elongated handle having a plurality of apertures at the upper end, each one of the plurality of apertures having one guide portion; a traveler disposed within the elongated interior space; a plurality of ribs secured to the traveler in a hinged fashion, the plurality of ribs extending from the traveler in the direction of the upper end of the elongated handle and passing through respective ones of the plurality of apertures, the ribs having a shaped side operatively engaged to the guide portion of the respective aperture; and a canopy attached to the plurality of ribs.

12. An umbrella comprising: a handle having an elongated outer housing thereon, the elongated outer housing having a first interior space; an inner sleeve disposed within the first interior space of the outer housing, the inner sleeve having a second interior space, the second interior space being internally threaded/geared and having upper and lower ends; a traveler disposed within the second interior space, a plurality of ribs secured to the traveler in a hinged fashion, the plurality of ribs extending from the traveler in the direction of the upper end of the elongated handle; a canopy attached to the plurality of ribs; and an electric motor connected to the inner sleeve.

13. The umbrella of claim 12, further comprising: a plurality of apertures at the upper end of the elongated outer housing, the apertures aligned with the plurality of ribs, the ribs passing through respective apertures.

14. The umbrella of claim 13, wherein the plurality of apertures further comprise: a plurality of notches.

15. The umbrella of claim 13, wherein the plurality of apertures further comprise: a plurality of guides disposed in the plurality of apertures and operatively engaged to the respective ribs passing therethrough.

16. The umbrella of claim 15, wherein the plurality of ribs further comprise: shaped sides, the plurality of guides operatively engaged to the respective ribs at the shaped sides.

17. The umbrella of claim 12, further comprising: a battery in operative electrical connection with the electric motor.

Description:

COPYRIGHT NOTICE

A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. 37 CFR 1.71(d).

CROSS-REFERENCE TO RELATED APPLICATIONS

N/A

FIELD OF THE INVENTION

This invention relates generally to umbrellas devices, and specifically to automatic umbrellas.

STATEMENT REGARDING FEDERALLY FUNDED RESEARCH

This invention was not made under contract with an agency of the US Government, nor by any agency of the US Government.

BACKGROUND OF THE INVENTION

Automatic umbrellas usually suffer from a number of defects. One first defect is that the typical automatic umbrella either has normal folding umbrella ribs to spread the canopy of the umbrella (as frequently seen in hand umbrellas and parasols), or else the simply folds the ribs down along the shaft of the umbrella (as frequently seen in table umbrellas and the like). Folding the ribs down the exterior leads to a larger exterior with a tendency to catch on passing objects even when the umbrella is not deployed, while using normal folding umbrella struts results in a device which is virtually certain to break soon as the weak and complex ribs eventually get bent or broken.

A second defect is the use of springs and elastic to operate the umbrellas. Since the typical hand umbrella has folding ribs which will soon break, the cost of using power mechanisms such as electrical motors becomes prohibitive. However, springs and the like provide an irregular action which may not fully deploy the umbrella in use. Electrical actuation would be superior.

Searching in the relevant prior art collections of the US Patent and Trademark Office reveals a number of motorized umbrellas of dissimilar design.

Electric motors operating umbrellas may be found in U.S. Pat. Nos. 7,188,633; 7,069,939; 4,572,226; 5,213,122; 5,449,012; 6,543,464; 5,141,010; 5,816,276; 3,129,715; 4,736,761; 6,182,917; 1,109,854; 4,523,607; and 5,291,908. While these devices teach rotating rods to power umbrellas, external travelers on an umbrellas stem, pulleys and various other mechanisms, none show ribs or struts riding on guides and extending through notches of the device. In addition, none show an internal traveler riding up an umbrella handle/body/shaft having threading on the interior of the shaft itself.

It would be preferable to provide an umbrella with notably simpler mechanisms for electrically operating the opening and closing of the umbrella as well as showing simple means by which rib/strut construction and deployment can both be drastically simplified to provide more reliable operation.

It would further be preferable to provide an umbrella which has stronger single piece ribs which are internally stowed when the umbrella canopy is not deployed.

SUMMARY OF THE INVENTION

General Summary

The present invention teaches an automatic umbrella which has one or more tubular handles/bodies with elongated cavities within.

A traveler assembly is located within a threaded cavity and comprises an electric motor, nose, and gear assembly which rides up or down the interior of the shaft/handle/body of the umbrella on threading/gearing on the interior of the umbrella shaft or interior of a rotating sleeve. In embodiments, the shape and resilience of the gear may effect the motion without internal threading/gearing of the shaft of the umbrella.

As the traveler assembly rises from the bottom of the interior to the top, the ribs (which are hingedly connected to the traveler at or near the nose) extend through notches or slots in the end of the umbrella, until the nose extends out the end of the umbrella or otherwise passes the notches and the continuing motion of the traveler actually drives the ribs to swing downward rather than extend further.

Motion of the single piece ribs is controlled by a pin or other type of guide on the side of the notch which cooperates with the shaped sides of the umbrella ribs, or a guide on the side of the ribs may extend into a smaller side-notch on the rib notch, thus using the same mechanism in mirror image.

Batteries and electric motor may be located in the traveler or in the shaft of the umbrella. A three position switch, buttons or other control may be used to provide the motor with either forward or reverse drive current, so the device may close itself by the opposite action as deployment, in which case the ribs will retract wholly or partially into the hollow body shaft.

The nose acts to tension the canopy in the deployed position.

Summary in Reference to Claims

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella comprising:

    • an elongated handle having an elongated interior space therein, the elongated handle being internally threaded and having upper and lower ends;
    • a traveler disposed within the elongated interior space, the traveler having an electric motor operatively connected to a gear, the gear being disposed in operative engagement with the internal threading of the elongated handle;
    • a plurality of ribs secured to the traveler in a hinged fashion, the plurality of ribs extending from the traveler in the direction of the upper end of the elongated handle; and
    • a canopy attached to the plurality of ribs.

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella, further comprising:

a battery in operative electrical connection with the electric motor.

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella, where in the traveler further comprises:

a nose at the upper end of the traveler.

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously to provide an umbrella wherein the nose of the traveler projects from the upper end of the traveler and contacts and tensions the canopy when the traveler is in a first position.

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella, wherein the nose further comprises:

a plurality of nose grooves aligned with the plurality of ribs and as deep as the ribs.

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella, further comprising:

    • a plurality of apertures at the upper end of the elongated handle, the apertures aligned with the plurality of ribs, the ribs passing through respective apertures.

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella, wherein the plurality of apertures further comprise:

a plurality of notches.

It is therefore yet another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella, wherein the plurality of apertures further comprise:

    • a plurality of guides disposed in the plurality of apertures and operatively engaged to the respective ribs passing therethrough.

It is therefore yet another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella, wherein the plurality of ribs further comprise:

    • shaped sides, the plurality of guides operatively engaged to the respective ribs at the shaped sides.

It is therefore yet another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella, further comprising:

    • a control having three positions, a first position in which no electrical current is supplied to the electrical motor, a second position in which a first polarity electrical current is supplied to the electrical motor, and a third position in which a reversed second polarity electrical current is supplied to the electrical motor.

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella comprising:

    • an elongated handle having an elongated interior space therein, the elongated handle having upper and lower ends, the elongated handle having a plurality of apertures at the upper end, each one of the plurality of apertures having one guide portion;
    • a traveler disposed within the elongated interior space;
    • a plurality of ribs secured to the traveler in a hinged fashion, the plurality of ribs extending from the traveler in the direction of the upper end of the elongated handle and passing through respective ones of the plurality of apertures, the ribs having a shaped side operatively engaged to the guide portion of the respective aperture; and
    • a canopy attached to the plurality of ribs.

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella comprising:

    • a handle having an elongated outer housing thereon, the elongated outer housing having a first interior space;
    • an inner sleeve disposed within the first interior space of the outer housing, the inner sleeve having a second interior space, the second interior space being internally threaded/geared and having upper and lower ends;
    • a traveler disposed within the second interior space, a plurality of ribs secured to the traveler in a hinged fashion, the plurality of ribs extending from the traveler in the direction of the upper end of the elongated handle;
    • a canopy attached to the plurality of ribs; and
    • an electric motor connected to the inner sleeve.

It is therefore yet another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella further comprising:

    • a plurality of apertures at the upper end of the elongated outer housing, the apertures aligned with the plurality of ribs, the ribs passing through respective apertures.

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella wherein the plurality of apertures further comprise:

a plurality of notches.

It is therefore yet another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella wherein the plurality of apertures further comprise:

    • a plurality of guides disposed in the plurality of apertures and operatively engaged to the respective ribs passing therethrough.

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella wherein the plurality of ribs further comprise:

    • shaped sides, the plurality of guides operatively engaged to the respective ribs at the shaped sides.

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide an umbrella further comprising:

a battery in operative electrical connection with the electric motor.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a user holding the umbrella of the invention just before use, while the umbrella is stowed.

FIG. 2 is a perspective view of a user holding the umbrella of the invention just after deploying it.

FIG. 3 is a partially cross-sectional view (or a view of the device with one side of the body removed) showing the significant internal structures of the device.

FIG. 4 is a side view of the umbrella in or near the position of use, with the fabric of the canopy removed.

FIG. 5 is a partially transparent view of the upper end of the umbrella with the ribs beginning to deploy, with the canopy removed: this view aids understanding of the mechanism for controlling the ribs.

FIG. 6 is a perspective view of the upper end of the umbrella with the canopy in place: this view corresponds to the view of FIG. 5.

FIG. 7 is a perspective view of the upper end of the umbrella with the canopy removed: this view corresponds to the views of FIGS. 5 and 6.

FIG. 8 is a partially cross-sectional view (or a view of the device with one side of the body removed) showing the internal structures of the device at a stage of deployment slightly more advance from the views of FIGS. 5 through 7.

FIG. 9 is a perspective view of the umbrella at the same stage of deployment as shown in FIG. 8.

FIG. 10 is a partially cross-sectional view (or a view of the device with one side of the body removed) showing the internal structures of the device at a stage of deployment slightly less advance from the views of FIGS. 8 and 9.

FIG. 11 is a perspective view of the umbrella at the same stage of deployment as shown in FIG. 10.

FIG. 12 is a perspective view of the device with the umbrella stowed in the body/handle portion.

FIG. 13 is an exploded view of the two parts of the body/handle and the main canopy/rib/motor assembly.

FIGS. 14a, 14b and 14c are cross-sectional partial views of one end of an embodiment having batteries in the handle or nose cone.

FIG. 15 is an exploded view of an embodiment having a rotating inner sleeve.

FIG. 16 is an assembled side view of the inner sleeve embodiment.

INDEX TO REFERENCE NUMERALS

  • Handle/body 100
  • Canopy 102
  • Interior space 104
  • Rib 106
  • Interior wall 108
  • Lower cavity end 110
  • Upper cavity end 112
  • Gear 114
  • Electric motor 116
  • Nose/tensioner 118
  • Nose groove 120
  • Notch 122
  • Control 124
  • Guide/retainer 125
  • Rib groove 126
  • Upper rib 128
  • Lower rib 130
  • Threads 132
  • Batteries 1402, 1404, 1406
  • Handle 200
  • Interior space 204
  • Rib 206
  • Interior wall (threaded/geared) 208
  • Gear 214
  • Electric motor 216
  • Nose/tensioner 218
  • Nose groove 220
  • Notch 222
  • Teeth/threads 232
  • Outer housing 240
  • Inner sleeve 242
  • Battery 244
  • Switch 246

DETAILED DESCRIPTION

FIG. 1 is a perspective view of a user holding the umbrella of the invention just before use, while the umbrella is stowed. FIG. 2 is a perspective view of a user holding the umbrella of the invention just after deploying it. It may be seen that handle/body/shaft 100 need not extend when canopy 102 is deployed, and that the user may easily deploy the umbrella one handed.

FIG. 3 is a partially cross-sectional view (or a view of the device with one side of the body removed) showing the significant internal structures of the device. Handle/body/shaft 100 has interior space 104. Rib 106 may sit therein when the device is not deployed and may extend in a semi-perpendicular fashion (as shown) when the device is deployed. (Canopy 102 is omitted from FIG. 3 and certain other figures for clarity.)

Interior wall 108 of the shaft 100 is threaded. The internally threaded shaft 100 allows use of a traveler which carries the ribs in and out of the interior cavity 104 (the traveler may be seen at upper end 112 of the cavity 104 and shaft 100 in FIG. 3, and has electric motor 116, gear 114 and nose 118).

Lower cavity/handle end 110 may have batteries (not shown) disposed therein or nearby in alternative embodiments, however in the best mode now contemplated and preferred embodiments such as FIG. 3, batteries are preferably located within the traveler nose 118, where they may be easily accessed when the umbrella is deployed, but where the need for wiring is minimized. Such a location for batteries 1406 may be seen in FIG. 14c.

Upper cavity/handle end 112 (at which the traveler is shown disposed in FIG. 3) is the location at which the traveler sits when the umbrella is fully in the open position or deployed position. Upper cavity/handle end 112 may advantageously be open.

(FIGS. 14a and 14b are cross-sectional partial views of one end of an embodiment having batteries in the handle. Batteries 1402, 1404 may be of a wide range of different types now known or later developed. Batteries may be rechargeable or replaceable.)

Nose/tensioner 118 may protrude as shown from the open upper end 112 when the canopy is fully deployed, which may result in the nose 118 pushing against the canopy and thus holding the canopy tight. The canopy may be attached to the nose as well as being attached to the ribs. The nose cone may be omitted in alternative embodiments.

Gear 114 may be operatively connected to electric motor 116 so that when electric motor 116 is actuated, gear 114 rotates. Gear 114 may be disposed in operative engagement with the threaded interior wall 108, so that rotation of gear 114 causes the traveler to move. Depending upon the polarity of current provided to the electrical motor, the rotation and thus motion may be either of two directions. Thus the device may advantageously have controls providing at least first and second polarities (normal and reversed) of current, as well as no current when the device is not being deployed or retracted.

The threading 132 (FIG. 8) on the interior of the shaft may take a number of forms, generally it may be a worm gear in the preferred embodiment. It may be continuous or interrupted, or even interrupted to the extent that the gearing becomes a rack and the gear a pinion. The threading 132 may be a worm gear, constant force thread, V-form, square, Acme, trapezoidal, power threads of all types, symmetrical, asymmetrical, class 1B, 2B, 3B, UN, UNF, coated or plated, or any other type of threading. The threads 132 may project from the wall or may be set thereinto, for example, a rack type threading may be a series of indentations or may be a series of projections from the wall. At the present time, a projecting power thread is preferred.

Nose groove 120 may be used in embodiments having large noses which entirely fill the interior cavity form side to side: nose groove 120 provides a space for the hinged ribs to enter when they are pulled back into the device. In alternative embodiments, the ribs may be hinged at a point higher up the nose, where it is narrower, or the nose may be narrower.

FIG. 4 is a side view of the umbrella with the fabric of the canopy removed. Notch 122 may be seen: the notches each have a respective rib projecting therefrom, and the action of the notch and rib is important, and will be discussed further in regard to FIGS. 5 through 7.

Control 124 may be a switch, a series of buttons, impedance detector, infrared and so on.

FIG. 5 is a partially transparent view of the upper end of the umbrella with the ribs beginning to deploy, with the canopy removed: this view aids understanding of the mechanism for controlling the ribs.

Guide/retainer 125 may be a projection from the notch 122 side, or it may be an indentation thereinto. The rib 106 may have a shaped side 126 which engages to the guide/retainer 125: rib groove 126 may be used if the guide is a projection and upper rib 128 and lower rib 130 may prevent it from leaving retainer 125, or the notch may be a type of aperture closed on all sides or narrowed at the top to prevent egress of the rib, or the guide/retainer 125 may be a relatively wider portion of the aperture 122 while the shaped side of rib 106 projects to engage into the wider portion.

FIG. 6 is a perspective view of the upper end of the umbrella with the canopy in place: this view corresponds to the view of FIG. 5. FIG. 7 is a perspective view of the upper end of the umbrella with the canopy removed: this view corresponds to the views of FIGS. 5 and 6. In FIG. 6, a transparent canopy may be seen. It will be appreciated that the device actually works better with an intermediate length of the ribs attached to the canopy, for example, the outer ends of the ribs only, or the outer ends and medial portions only with the internal rib ends free of the canopy (and vice-versa) so that the canopy's center is free to be tensioned by nose 118 and may fold more freely under use.

FIG. 8 is a partially cross-sectional view (or a view of the device with one side of the body removed) showing the internal structures of the device at a stage of deployment slightly more advance from the views of FIGS. 5 through 7. FIG. 9 is a perspective view of the umbrella at the same stage of deployment as shown in FIG. 8.

Gear 114 may be seen to have a fairly aggressive angle of advance, as the traveler will not need to exert great strength when moving up and down the interior of the device on threads 132.

The traveler may be seen to have pulled the ribs partially into the handle/shaft/body, and the ribs at this point continue to move substantially axially, but are beginning to deploy sideways.

FIG. 10 is a partially cross-sectional view (or a view of the device with one side of the body removed) showing the internal structures of the device at a stage of deployment slightly less advance from the views of FIGS. 8 and 9. FIG. 11 is a perspective view of the umbrella at the same stage of deployment as shown in FIG. 10. The ribs are nearly entirely within the handle.

FIG. 12 is a perspective view of the device with the umbrella stowed in the body/handle portion. The tips of the ribs are barely visible within the apertures.

FIG. 13 is an exploded view of the two parts of the body/handle and the main canopy/rib/motor assembly. The body is shown with two halves, but other forms of construction may be used. The ribs may be seen tightly bunched inside the interior space.

Reverting to FIG. 5, it will be understood that traveler actually pushes the rib internal ends up to the guides/retainers 125 of the apertures 122. This causes the hinged ribs 106 to sweep/swing downwards, quickly spreading the canopy 102 and tensioning it while bringing the canopy into a traditional “umbrella” shape. However, it will be seen that the ribs may be considerably stronger than conventional ribs, as the ribs at no point fold and need have no joints. The ribs may be stiff or flexible as desired for the shape and configuration of the device.

FIG. 15 is an exploded view of an embodiment having a rotating inner sleeve, while FIG. 16 is an assembled side view of the inner sleeve embodiment. Handle 200 may have therein electric motor 216 and battery 244 in operative electrical connection thereto. When actuated, the motor will turn. However, in this embodiment the electric motor 216 is connected to inner sleeve 242, a separate tubular piece which sits within outer housing 240. Inner sleeve 242 has threaded/geared interior wall 208, which is threaded 232 and in operative mechanical engagement to threading upon the traveler, which is free to move up and down in interior space 204 on gear 214.

It may be seen that in operation, switch 246 actuates the motor 216 whose turning will cause the inner sleeve 242 to rotate, which will act upon the traveler having grooves 220 allowing the ribs to fold tightly within the interior, which traveler will in turn be forced to move upward on the threads on the threaded/geared interior wall 208. Since rib 206 is engaged in notch 222, rotation is constrained and the traveler will begin to rise up the interior space 204, pushing rib 206 out through notch 222 and extending the umbrella. Nose 218 will then tension the umbrella canopy.

This embodiment has an extra moving part but is believed to be more reliable.

The disclosure is provided to render practicable the invention by those skilled in the art without undue experimentation, including the best mode presently contemplated and the presently preferred embodiment. Nothing in this disclosure is to be taken to limit the scope of the invention, which is susceptible to numerous alterations, equivalents and substitutions without departing from the scope and spirit of the invention. The scope of the invention is to be understood from the appended claims.