Abstract:
The present invention relates to a closure suitable for dispensing pourable product from a container. More specifically, the present invention is directed to a “twist to open” type closure operated by a twisting action.

Description:
TECHNICAL FIELD  
       [0001]     The present invention relates to a closure suitable for dispensing pourable product from a container. More specifically, the present invention is directed to a “twist to open” type closure operated by a twisting action.  
       BACKGROUND OF THE INVENTION  
       [0002]     Dispensing closures for containers are commonly known in the art and may be based on various opening mechanisms such as “push and turn”, “twist and turn”, “twist to open” or “push and pull”. Those closures are commonly used in combination with containers designed to contain products such as food, beverages, personal care products, pharmaceutical or cosmetic products. Typical types of dispensing closures are for example described in U.S. Pat. No. 6,202,876 (push and twist), U.S. Pat. No. 5,305,932 (snap-on), U.S. Pat. No. 2,004,015507 (push and pull) or in WO 2004/110889 (push to open). The specific type of “twist to open” closures is described for example in U.S. Pat. No. 5,305,932; EP-B1-0 378 488; WO 00/30949; EP-A1-0 417 891 and in WO 03/050033.  
         [0003]     Although the above-types of closures will generally function satisfactorily in the applications for which they are designed, they typically only permit slow dispensing of limited amount of fluids. However, in certain circumstances, it is required to dispense the contained products much faster and in a relatively large quantity. This is typically the case in the context of liquid detergent containers. It has indeed been discovered that the users of containers equipped with the corresponding dispensing closures primarily seek for the fastest possible delivery of the contained liquid detergent into an appliance or receptacle. Most commonly used closures for containers adapted for delivering liquid detergent compositions, which are typically viscous liquids by nature, are described e.g. in EP-B1-0 109 704. Those dispensing closures typically consist of two separate parts: a spouted transition piece and a screw-type cap. Although the spouted piece allows for precise pouring of the viscous liquid into the intended receptacle, the cap is however often seen as difficult and/or too long to open and may easily get lost.  
         [0004]     Another drawback associated with the use of the above dispensing system is that under usage, liquid detergent compositions may be spilled in the area where liquid detergent is consumed and/or on the user&#39;s hands which may lead to skin irritation or even burns. This often occurs when the above-mentioned cap is also used as a dosing means.  
         [0005]     It is therefore an objective of the present invention to provide a dispensing closure suitable for dispensing pourable product from a container which provides fast dispensing of the contained product, which is easy-to-use, mess-free and which overcomes the above-mentioned drawbacks.  
         [0006]     It has now been found that the above objective can be met by providing a dispensing closure  1  according to the present invention.  
         [0007]     Advantageously, the dispensing closure  1  according to the present invention exhibits improved opening/closing ergonomics. A further advantage associated with the dispensing closure  1  according to the present invention is that it provides excellent sealing vis-à-vis the contained product.  
         [0008]     It is still another advantage that, due its particular configuration, the dispensing closure  1  of the present invention provides more convenient way of dispensing pourable product and allows better viewing of the amount of product being dispensed.  
         [0009]     It is still a further advantage that the dispensing closure  1  of the present invention requires a minimum number of components, which greatly facilitates its manufacture and assembly, and substantially reduces the associated production costs. In addition, the dispensing closure  1  of the present invention provides a more aesthetic appeal when compared to similar closures known in the art, and contributes to provide the user with a more pleasant experience while operating domestic tasks.  
         [0010]     Advantageously, the dispensing closure  1  according to the present invention does not require any modification of the container  2  on which it is mounted, for the dispensing closure  1  to become operable.  
         [0011]     Other advantages and more specific properties of the dispensing closure  1  according to the present invention will be clear after reading the following description of the invention in combination with the attached drawings.  
       SUMMARY OF THE INVENTION  
       [0012]     The present invention relates to a dispensing closure  1  suitable for being mounted on a container  2 , the container  2  having a dispensing opening  3  and being suitable for containing a pourable product in its interior volume, wherein the dispensing closure  1  comprises: 
        (a) a base member  7  comprising a means for attachment  6  to said container  2 , a draining canal  12  adapted to communicate with the interior volume of the container  2 , a discharging means  13  and a hollow sleeve  15 ; wherein the hollow sleeve  15  is adapted to communicate with the draining canal  12  and comprises a dispensing aperture  18  capable of dispensing the pourable product.     (b) a cap  19  comprising a cap top  20  and a barrel  21  extending downwardly from the cap top  20 , whereby the cap top  20  is capable of covering the discharging means  13  in a tight manner vis-à-vis the content of the container  2 ;     (c) complementary means  27 , 28  of raising and lowering the cap  19  by rotation thereof, wherein the complementary means  27 , 28  are located in the barrel  21  and the hollow sleeve  15 , and are adapted to switch the cap  19  from a lower position wherein said discharging means  13  is covered by the cap top  20  and the dispensing aperture  18  is obstructed by the barrel  21 , and an upper position wherein the discharging means  13  is uncovered and the dispensing aperture  18  is unobstructed.        
 
         [0016]     In another embodiment, the present invention is directed to a container closure assembly, comprising: 
        (a) a container  2  having a body portion  4  for holding container content, a lower closed end for supporting the container  2 , an upper end including a means of attachment  30  thereon adapted to receive and affix a dispensing closure for containers; and     (b) a dispensing closure  1  as above-indicated, mounted on the container  2 .        
 
         [0019]     The present invention further encompasses a method of dispensing the content of a container  2  comprising the steps of: 
        (a) providing a container closure assembly as above-described, wherein the cap  19  is in its lower position;     (b) rotating the cap  19  so as to raise the cap  19  to its upper position;     (c) pouring the required amount of the container content through the discharging means  13 ;     (d) rotating the cap  19  so as to lower the cap  19  back towards its lower position.       
 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]      FIG. 1  is a cross-section view of a container closure assembly according to the present invention. The assembly comprising a container  2  onto which is mounted a dispensing closure  1  according to another embodiment of the invention.  
         [0025]      FIG. 2  is a top perspective view of a dispensing closure  1  according to the invention in its lower/closed position.  
         [0026]      FIG. 3  is a top perspective view of a dispensing closure  1  according to the invention in its upper/open position.  
         [0027]      FIG. 4  is a bottom perspective view of the cap  19  for use in a dispensing closure  1  according to the invention.  
         [0028]      FIG. 5  is a top perspective view of the base member  7  for use in a dispensing closure  1  according to the invention.  
         [0029]      FIG. 6  is a top view of a dispensing closure  1  according to the invention in its lower/closed position.  
         [0030]      FIG. 7  is a top view of a dispensing closure  1  according to the invention in its upper/open position.  
         [0031]      FIG. 8  is a side view of a dispensing closure  1  according to the invention in its lower/closed position.  
         [0032]      FIG. 9  is a side view of a dispensing closure  1  according to the invention in its upper/open position.  
         [0033]      FIG. 10  is a cross-sectional side view of a dispensing closure  1  according to the invention in its lower/closed position.  
         [0034]      FIG. 11  is a cross-sectional side view of a dispensing closure  1  according to the invention in its upper/open position. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0035]     For the purposes of promoting and understanding the principles of the present invention, reference will be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. While this invention is susceptible of embodiments in many different forms, this specification and the accompanying drawings discloses specific forms as examples of the invention. However, the invention is not intended to be limited to the embodiment so described.  
         [0036]     In a first embodiment, the present invention is directed to a dispensing closure  1  suitable for being mounted onto a container  2  having a dispensing opening  3 .  
         [0037]     Referring now to  FIG. 1 , a dispensing closure  1  according to a first embodiment of the invention is represented which is mounted onto a container  2 .  
         [0000]     Container  2   
         [0038]     In a preferred embodiment, the container  2  comprises a body portion  4  for holding container content, a lower closed end for supporting said container  2 , an upper end including a neck  5  delimiting a dispensing opening  3 . The dispensing closure  1  of the present invention may be securely mounted onto said container  2 , via its base member  7 , using any means of attachment commonly know to those skilled in the art including cooperative threads, crimping, clipping means, heat sealing force fitting, clasp elements, snap-fit bead, groove arrangements, and mixtures thereof.  
         [0039]     Preferably, the dispensing closure  1  of the invention is provided with an inner female thread  6  typically located in the base member  7 , as described hereinafter, and the container neck  5  is provided with a male thread  30  formed adjacent its dispensing opening  3 . Typically, the dispensing closure  1  is mounted onto the container  2  with the female thread  6  of the base member  7  screwed on the male thread  30  of the container  2 .  
         [0040]     Alternatively, the container  2  may not need to have a neck  5 . Instead the container  2  may consist of a just a body portion  4  with a dispensing opening  3 . The dispensing closure  1  of the present invention is suitable for use with a variety of conventional or special containers having various designs, the details of which, although not illustrated or described, would be apparent to those skilled in the art. The container  2  may have a rigid wall or walls, or may have a somewhat flexible wall or walls.  
         [0041]     In a preferred aspect of the invention, the dispensing closure  1  is a separate element which is adapted to be removably or non-removably mounted, via its base member  7 , to a previously manufactured container  2  which has a dispensing opening  3  to the container interior. The dispensing closure  1  is adapted to be used with a container  2  having a dispensing opening  3  to provide access to the container interior volume and to a product contained therein, which is preferably a pourable product. However, the dispensing closure  1  of the invention may be used with many products, including but not limited to, relatively low or high viscosity liquids, creams, gels, suspensions, mixtures, lotions, pastes, particulates, granular products, and mixtures thereof. Typical products for use in the present invention may be those constituting a food product, a personal care product, an industrial or household cleaning product, or other compositions of matter for use in activities involving manufacturing, commercial or household maintenance, construction, agriculture.  
         [0042]     Preferably, said pourable product is a liquid composition, more preferably a viscous liquid composition, most preferably a laundry liquid detergent composition.  
         [0000]     Base Member  7   
         [0043]     The dispensing closure  1  according to the present invention comprises as a first essential element, a base member  7 .  FIG. 5  shows is a top perspective view of the base member  7  for use in the dispensing closure  1  according to the invention.  
         [0044]     The base member  7  is intended to be mounted onto a container  2  using any suitable means of attachment as indicated above. Suitable means of attachment are designed so as to provide secure sealing between the dispensing closure  1  and the container  2  vis-à-vis its content.  
         [0045]     The base member  7  may have any suitable configuration, form or dimension for accommodating an upwardly projecting neck  5  or portion of a container  2 . A preferred execution of the present invention, wherein the base member  7  has a substantially egg-like shape, preferably an egg-like shape, more preferably an elliptical shape, when seen from the top, as represented in the accompanying drawings.  
         [0046]     The base member  7  is comprised of two distinct parts: a skirt  8  and a platform  9 . The skirt  8  generally forms the lower part of the base member  7  and extends substantially towards the container direction, typically parallel to the neck  5  of the container  2 . Preferably, the skirt  8  has a substantially cylindrical shape, preferably a cylindrical shape. The platform  9 , which typically extends substantially transversely to the longitudinal axis of the container  2 , generally corresponds to the upper part of the base member  7 . In a preferred execution of the present invention, the platform  9  has a substantially flat, plate-like shape and is provided with a platform lip  10  extending substantially over the outer perimeter of said platform  9 . Platform  9  may be substantially horizontal. However, according to a highly preferred embodiment, platform  9  may be adapted such as to have an inclination of between 5 and 45 degrees, preferably between 10 and 40 degrees, more preferably between 20 and 30 degrees, most preferably between 20 and 25 degrees, above a virtual horizontal axis. As shown in  FIG. 10  and  FIG. 11 , the means for attachment  9  is preferably located onto the inner wall  11  of the skirt  8 .  
         [0047]     Also shown in  FIG. 10  and  FIG. 11 , the base member  7  further comprises a draining canal  12  adapted to communicate with the interior volume of the container  2  such as to permit dispensing of the container content by the discharging means  13 , via the dispensing opening  3  and the dispensing aperture  18 , when the cap  19  is in its upper position. Said draining canal  12  is typically delimited by the contours of said skirt  8 .  
         [0048]     Discharging means  13  for use herein may be readily recognized and selected by those skilled in the art. Preferably, said discharging means  13  is a pouring spout. In a more preferred execution, the discharging means  13  is a beveled spout which extends upwardly from said base member  7 , preferably from said platform  9 . Such preferred spout allows better control and more precise dispensing of the container content, especially viscous liquids such as liquid detergents. It is preferred that said discharging means  13  has a substantially annular shape.  
         [0049]     In a further preferred embodiment of the present invention, said discharging means  13  is located in such a way as to form spacing between said discharging means  13  and the outer perimeter of said platform  9 . Said spacing may preferably take the form of a circular drainer  14  adapted to recuperate any pourable product contained within the container  2 , preferably viscous liquid product, which would not have been properly dispensed from said discharging means  13 . Also, said spacing is preferably provided with apertures  33  communicating with the interior of the container  2  so as to permit the recuperated product to be drained back into the container  2 . Additionally, said apertures  33  will also constitute air intake means adapted to allow air to penetrate into the container  2  in response to the evacuation of its content and thereby contribute to a better dispensing of the container content, preferably viscous liquids.  
         [0050]     Referring now specifically to  FIG. 5 , the base member  7  further comprises a hollow sleeve  15  adapted to communicate with said draining canal  12 . The hollow sleeve  15  shall be adapted so as engage the hereafter-described barrel  21  for axial motion with respect to said hollow sleeve  15 . Suitable hollow sleeve  15  for use herein will be readily apparent to those skilled in the art. However, in a preferred execution, said hollow sleeve  15  has a substantially cylindrical shape, preferably a cylindrical shape, and is provided with an inner  16  and an outer surface  17 . Preferably, said hollow sleeve  15  extends upwardly from said base member  7 , more preferably from said platform  9 , and is open at both ends.  
         [0051]     The hollow sleeve  15  may extend substantially towards the container direction, typically parallel to the neck  5  of the container  2  and therefore towards a substantially vertical axis. In a highly preferred embodiment however, said hollow sleeve  15  may be positioned such as to have an inclination of between 5 and 45 degrees, preferably between 10 and 40 degrees, more preferably between 20 and 30 degrees, most preferably between 20 and 25 degrees, below a virtual vertical axis.  
         [0052]     According to the present invention, said hollow sleeve  15  is provided with a dispensing aperture  18  capable of dispensing the pourable product contained into said container  2 , and positioned such as to communicate with said discharging means  13 .  
         [0053]     The constituting parts of the base member  7  are formed from any suitable material commonly known in the art. Preferably, said parts are all formed from heat sealable thermoplastic materials such as polyethylene or polypropylene single piece. Accordingly, and in a preferred execution of the invention, the base member  7  is a monolithic piece formed from the same thermoplastic material. According to this specific embodiment, the different parts may be advantageously molded within a single injection molding operation which therefore involves both a simple and economical manufacturing process.  
         [0000]     Cap  19   
         [0054]     The dispensing closure  1  according to the present invention is further provided with a cap  19 , the role of which is to cover the discharging means  13  in a tight manner vis-à-vis the content of the container  2  when said cap  19  is in its lower/closed position.  FIG. 4  shows a bottom perspective view of said cap  19 .  
         [0055]     The cap  19  for use herein is comprised of two distinct parts: a cap top  20  and a barrel  21 . The cap top  20  generally forms the upper part of the cap  19  and extends substantially transversely to the longitudinal axis of the container  2 . It is typically provided with an inner face  32  and an outer surface  31 .  
         [0056]     The cap top  20  for use herein may however have any suitable configuration, form or dimension for accommodating said platform  9  and said discharging means  13 . Suitable cap tops  20  for use herein will easily be recognized by those skilled in the art. In a preferred execution, the cap  19  has a substantially rounded shape which will allow proper covering of said discharging means  13 . Preferably, the cap  19  has a concave form with the concavity turned towards the direction of the platform  9 . More preferably, the cap top  20  is provided with a substantially egg-like shape, preferably an egg-like shape, more preferably an elliptical shape, when seen from the top, as represented in the accompanying drawings.  
         [0057]     In a highly preferred execution of the present invention, said cap top  20  is further provided with a front screen  24  which is intended to selectively cover the extremity of said discharging means  13 . Typically, said front screen  24  is located at the front part of said cap top  20 .  
         [0058]     The cap top  20  for use herein preferably possesses a cap lip  25  which is typically a substantially annular lip and which extends over the outer perimeter of said cap top  20 . In that preferred embodiment, the cap lip  25  is adapted to tightly conform to the platform lip  10  contours, so as to provide a first sealing means of said cap  19  onto the base member  7  vis-à-vis the content of the container  2  when said cap  19  is in its lower/closed position.  
         [0059]     According to a preferred aspect of the invention, the outer surface  31  of said cap top  20  is further provided with a gripping means  26 , which is preferably a finger grip and which is typically located at the back part of the cap top  20 . Any gripping means commonly known in the art may be used in the context of the present invention. In a very preferred embodiment, the gripping means  26  is especially adapted to provide suitable gripping by pinching with two fingers. The exterior configuration of the cap top  20  for use herein may be varied as desired for aesthetic appearance or for further improved gripping. The latter may be e.g. provided with incrustations, serrations, grooves, indentations or any other operation commonly know in the art.  
         [0060]     As show in  FIG. 4 , the cap  19  is further provided with a barrel  21  which generally forms the lower part of the cap  19 . Said barrel  21  typically extends substantially transversely to the plan formed by said cap top  20 .  
         [0061]     The barrel  21  for use herein may however have any suitable configuration, form or dimension for accommodating said discharging means  13  and in particular said hollow sleeve  15 . Suitable barrel  21  for use herein will easily be recognized by those skilled in the art. However, in a preferred execution, said barrel  21  has a substantially cylindrical shape, preferably a cylindrical shape, and is provided with an inner  22  and an outer surface  23 . Preferably, said barrel  21  extends downwardly from said cap top  20  and is open at the end (i.e. lower end) opposite to that facing said cap top  20  (i.e. upper end).  
         [0062]     As previously mentioned, the barrel  21  is adapted so as to be engaged for axial motion with respect to said hollow sleeve  15 . Accordingly, and in a highly preferred embodiment of the present invention, the outer diameter (corresponding to the outer surface  23 ) of said barrel  21  is slightly inferior to the inner diameter (corresponding to the inner surface  16 ) of said hollow sleeve  15 . According to this preferred embodiment, the barrel  21  is allowed to axially slide within the interior of said hollow sleeve  15 , via the hereinafter described complementary means  27 , 28  of raising and lowering the cap  19 , while still providing efficient air tight seal (second sealing means) vis-à-vis the content of the container  2  when said barrel  21  obstructs said dispensing aperture  18 .  
         [0063]     In another highly preferred execution, the lower end of said barrel  21  is provided with a cross section which is non-perpendicular to the longitudinal axis thereof. As represented in  FIG. 10  and  FIG. 11 , the barrel  21  for use in the present invention is preferably provided with a beveled lower end. According to this highly preferred embodiment, the dispensing aperture  18  may be unobstructed/obstructed with a limited rotation of said cap  19  and thus much faster than with the configuration where the lower end of said barrel  21  in non-beveled.  
         [0064]     The cap  19  for use in the present invention may be formed from any suitable material commonly known in the art. Preferably, said cap  19  is formed as a single piece from heat sealable thermoplastic materials such as polyethylene or polypropylene single piece.  
         [0000]     Complementary Means  27 , 28  of Raising and Lowering the Cap  19   
         [0065]     The dispensing closure  1  according to the present invention further comprises, as another essential technical feature, complementary means  27 , 28  of raising and lowering said cap  19  by rotation thereof.  
         [0066]     Complementary means  27 , 28  for use in the present invention are located in said barrel  21  and in said hollow sleeve  15 , and are adapted for switching said cap  19  from a lower position and an upper position, by rotation of said cap  19 .  
         [0067]     Suitable complementary means  27 , 28  for use herein will easily be recognized by those skilled in the art. Those include but are not limited to angled or helical threads, helical grooves or notches, in combination with complementary helical threads or lugs  
         [0068]     According to a preferred embodiment of the present invention, the complementary means  27 , 28  of raising and lowering said cap  19  by rotation thereof, are a cooperative combination of discontinuous helical grooves  27  and lugs  28 . In a more preferred execution, and as represented in  FIG. 4  and  FIG. 5 , said helical grooves  27  are located in said hollow sleeve  15 , preferably in the inner surface  16  of said hollow sleeve  15 , and said lugs  28  are positioned in said barrel  21 , preferably in the outer surface  23  of said barrel  21 .  
         [0069]     In the illustrated embodiment, two such helical grooves  27  are provided at an angular increment of 180 degrees. The corresponding two lugs  28  are preferably spaced at 180 degrees increment as well. In a preferred execution, said lugs  28  have a substantially cylindrical shape, preferably a cylindrical shape, to conform to and slide within the corresponding grooves  27 .  
         [0070]     As indicated above, the complementary means  27 , 28  of raising and lowering said cap  19  by rotation thereof, are adapted to switch said cap  19  from a lower/closed position to an upper/open position. According to a highly preferred execution of the present invention, said complementary means  27 , 28  are adapted so as to allow said cap  19  to be switched from said lower position to said upper position through a limited angular displacement, preferably 180 degrees. In a very preferred embodiment, said helical grooves  27  are adapted such as angular displacement of more than 180 degrees is not permitted. This may be achieved e.g. by means of suitable rotation stops  29 , as represented in  FIG. 5 .  
         [0071]     In the normal course of a closing/opening operation, while said cap  19  is in its lower/closed position (see  FIG. 10 ), the dispensing aperture  18  is obstructed by said barrel  21  and therefore seals the content of the container  2 . Also, while said cap  19  is its lower position, said cap top  20  covers the discharging means  13  which provides a further sealing means for the container content and provides a visual indication that the dispensing container according to the invention is in its closed position.  
         [0072]     While said cap  19  is being engaged in a rotational movement, said complementary means  27 , 28  are working in cooperation so as to progressively raise said cap  19  towards the axis of said hollow sleeve  15 . As the cap  19  is rising, said dispensing aperture  18  is becoming progressively less and less obstructed until it is completely unobstructed. Concurrent to this axial motion, said cap top  20  is progressively uncovering said discharging means  13 .  
         [0073]     When said dispensing aperture  18  is completely unobstructed, the cap  19  has attained its open position, allowing the content of the container  2  to be dispensed through the discharging means  13  via said dispensing aperture  18 .  
         [0074]     In a highly preferred execution of the present invention, said complementary means  27 , 28  and said barrel  21  are adapted and configured so as to allow said cap  19  to be switched from the lower position to the upper position through an angular rotation of preferably 180 degrees.  
         [0075]     In the context of the present invention, it is preferred that said complementary means  27 , 28  are integrally part of the specific elements they are located in. More specifically and according to a highly preferred embodiment, said helical grooves  27  are preferably integrally part of said hollow sleeve  15  and said lugs  28  are preferably integrally part of said barrel  21 .  
         [0000]     Container Closure Assembly  
         [0076]     In another embodiment, the present invention is directed to a container closure assembly, comprising: 
        (a) a container  2  having a body portion  4  for holding the container content, a lower closed end for supporting the container  2 , an upper end including a means of attachment thereon adapted to receive and affix a dispensing closure for containers;     (b) a dispensing closure  1  according to the invention, mounted on the container  2 . 
 
 A Method of Dispensing the Content of a Container  2  
       
 
         [0079]     The present invention further encompasses a method of dispensing the content of a container  2  comprising the steps of: 
        (a) providing a container closure assembly according to the invention, wherein said cap  19  is in its lower position;     (b) rotating said cap  19  so as to raise said cap  19  to its upper position;     (c) pouring the required amount of the container content through said discharging means  13 ;     (d) rotating said cap  19  so as to lower said cap  19  back towards its lower position.        
 
         [0084]     Use of a container closure assembly according to the invention, for dispensing a liquid composition.  
         [0085]     In a further embodiment, the present invention is directed to the use of a closure assembly according to the present invention for dispensing a liquid composition, preferably a liquid detergent composition, most preferably a liquid laundry detergent composition.  
         [0086]     The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm”.  
         [0087]     All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention. To the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.  
         [0088]     While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.