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Title:
METHOD AND APPARATUS FOR SEALING
Document Type and Number:
WIPO Patent Application WO/2000/078546
Kind Code:
A1
Abstract:
A method for sealing component parts (11, 12) together by placing the component parts adjacent to each other, interposing an electrically resistive wire (20) between the parts and passing an electric current through the wire to cause the temperature of the wire to rise. When sealing component parts made of certain types of materials having a relatively low softening point, such as plastic or other polymeric material, the component parts are urged toward each other so that when the wire becomes heated it will cause the surface of each plastic component part in contact with the wire to soften. When sealing component parts made of other types of materials, such as glass, metal or other materials having relatively high softening points, the wire will have a coating of hot melt glue which will soften and adhere to the surfaces to be bonded when the electrical resistive wire is heated by passing a current through it.

Inventors:
MIRAGLIA PHILIP J (US)
Application Number:
PCT/US2000/016990
Publication Date:
December 28, 2000
Filing Date:
June 21, 2000
Export Citation:
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Assignee:
MIRAGLIA PHILIP J (US)
International Classes:
B29C65/34; (IPC1-7): B32B31/00
Foreign References:
US2647072A1953-07-28
DE4101215A11992-07-23
US4586624A1986-05-06
JPS59118426A1984-07-09
US3047703A1962-07-31
Attorney, Agent or Firm:
Dresner, Arthur (LLP 261 Madison Avenue New York, NY, US)
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Claims:
WHAT IS CLAIMED IS:
1. A method for sealing together component parts comprising: placing said component parts adjacent each other; interposing an electrically resistive wire between said component parts; applying a force to said component parts causing said component parts so as to urge said component parts toward each other and into physical contact with said wire along a contact surface of each said component part; causing an electric current to pass through said wire in order to raise the temperature of said wire above the softening point of the materials of construction of said parts and to cause said contact surface of each part in contact with said wire to reach its softening point; continuing to apply said force to said component parts when said contact surfaces have reached said softening point so that said softened parts will come in contact with each other and be sealed together; and removing said electric current from said wire allowing said wire and said parts to cool so that said softened contact surfaces will harden forming a seal there between.
2. The method according to claim 1, further comprising the step of coating said wire with a hot melt adhesive prior to interposing said wire between said parts so that upon passing said electric current through said wire said hot melt adhesive will soften causing said parts to adhere together.
3. The method according to claim 2 wherein said electrically resistive wire has a circular crosssection.
4. The method according to claim 2 wherein said electrically resistive wire has a rectangular crosssection.
5. The method according to claim 2 wherein said electrically resistive wire has a crosssection with an aspect ratio of at least 3 to 1.
6. A method for bonding first and second components of a toner cartridge together, said first and second components being constructed of polymeric material, said first component comprising an open hopper having two opposing side walls and two opposing end walls, said side walls and said end walls having exposed edge surfaces defining an opening to the interior of said hopper; said second component comprising a cover having a dispensing mechanism for dispensing toner material housed within said first component when said second component is assembled with said first component to cover said opening, said second component having planar surfaces arranged to fit complimentary with said exposed edge surfaces of said side and end walls, wherein said method comprises the step of placing an electrically resistive wire between said planar surfaces of said second component and at least one exposed edge surface of said first component with the ends of said wire exposed for connection to a source of electrical current; urging said first and second components toward each other; and passing an electric current through said electrically resistive wire causing said wire to become heated to a temperature which will produce softening of the material of said first and second components whereby said softened material of said first and second components will adhere to each other and to said wire; and removing said electric current from said wire causing said wire to cool causing said softened material of said first and second components to harden and bond to each other.
7. The method according to claim 6 further comprising the step of cutting said exposed ends of said wire after said wire has cooled and said components have become bonded together.
8. The method according to claim 6 further comprising the step of bending said exposed ends of said wire along an outside surface of at least one of said components after said wire has cooled and said components have become bonded together.
9. The method according to claim 6 further comprising the step of coating said wire with a hot melt adhesive which is in a nonadhering condition at room temperature prior to placing said wire between said first and second components, whereby said hot melt adhesive will soften into an adhesive condition when said wire is heated in order to bond with the facing surfaces of said first and second components.
10. The method according to claim 6 wherein an electrically resistive wire is placed between said planar surfaces of said second component and at least two of said exposed edges.
11. The method according to claim 10 wherein said two exposed edges are the exposed edges of said two opposing side walls.
12. The method according to claim 11 wherein said exposed ends of said wire are located at opposite ends of said side walls.
13. The method according to claim 11 wherein said exposed ends of said wire are located at the same end of said side walls.
14. The method according to claim 10 wherein said two exposed edges are the exposed edge of one of said side walls and one of said end walls.
15. The method according to claim 6 wherein an electrically resistive wire is placed between said planar surfaces of said second component and the exposed edges of said two opposing side walls and at least one of said end walls.
16. The method according to claim 15 wherein said electrically resistive wire is placed between said planar surfaces of said second component and the exposed edges of said two opposing side walls and said two opposing end walls.
17. The method according to claim 6 further comprising the step of placing a closed cell foam gasket between said planar surfaces of said second component and the exposed edges of said first component that have no wire placed there between.
18. An electrically resistive wire coated with a hot melt adhesive which does not have adhesive characteristics at room temperature and which will soften and become tacky to acquire adhesive quality upon passing an electric current through said wire for use in bonding components together according to the method of claim 2. 19.
19. The electric wire according to claim 18 wherein said wire has an electrical resistance of sufficient value to cause said wire to become heated and thereby render said hot melt adhesive to acquire adhesive quality upon applying an appropriate voltage to said wire.
20. The electric wire according to claim 18 wherein said wire has a resistance value of between 650 and 750 ohms per CMF.
21. The electric wire according to claim 20 wherein the ends of said wire are placed adjacent each other.
Description:
METHOD AND APPARATUS FOR SEALING BACKGROUND OF THE INVENTION The present invention relates generally to the field of sealing components of various compositions or materials of construction together, and more particularly to a method and means for causing such components to be bonded and sealed together quickly, inexpensively and in such a manner that they can be readily unsealed and detached from each other. In a particular application, the invention is used for sealing components of an ink or toner cartridge together.

There are of course numerous methods known in the art for sealing or bonding various types of items together. These methods range from the use of a variety of adhesives to various types of welding techniques. Depending upon the nature of the items to be bonded together, the materials of construction of such items and the requirements for such bonding, different techniques will be employed. When bonding components together to form a container for housing liquids, fine powders, or other fluid materials it is important that the seal between the components be absolute so that there is no leakage of the fluid material through the sealed components. In many situations it is desirable to have access to the interior of such a sealed container for replenishing the fluid material. In such situations, it is sometimes necessary to separate previously sealed components to gain access to the interior of the container and to then reseal the separated components after the container is refilled. Examples of such containers that contain fluid material which is frequently replenished include battery casings, ink cartridges used in printing devices and toner cartridges which carry either liquid or fine powder toner for use

in office copying machines.

For the sake of simplifying an understanding of the present invention, the invention will be described and illustrated herein in connection with unsealing and resealing the major components of an office copier type of toner cartridge container which components are constructed of polymeric materials. However, it should be understood that the principles of the invention are applicable to other types of components made or constructed of any type of material having surfaces that are to be sealed or otherwise joined together.

The development of the xerographic photocopying process has led to the expansion of this copying technology to other devices, such as printers used with computers. Devices using the xerographic printing or digital imaging systems frequently use a dry fine powder toner, which is often supplied in a cartridge to be installed in a printer or office copying machine from which toner is dispensed as required during printing operation. Such cartridges typically include many structural components and functional elements, such as toner hoppers, toner dispensing rollers, photo conductor rollers, operating levers, etc., and are accordingly relatively costly to replace when the toner supply is depleted. However, the rollers and other hardware which are generally included with such cartridges, are often sufficiently durable to last through several refills of toner in a given cartridge. Thus, the discarding of the cartridge and accompanying hardware when the toner is depleted, is quite costly and wasteful.

Manufacturers of such cartridges are well aware of this problem, but of course desire to maximize profits by selling new toner cartridges, complete with new rollers, platens, levers and other hardware, even though all that may be needed by the customer is a fresh supply of toner within the cartridge. In fact, in at least some cases, manufacturers of such cartridges have included features in the cartridge which complicate the disassembly or opening of the cartridge for replenishment of the toner supply and seal therein, in order to discourage the refilling and reuse of the cartridges by the consumer.

Many, if not most, users of such cartridges try to reuse their cartridges in order to reduce expense; a refilled and reused cartridge may cost only one half or less than that of the price of a new cartridge. However, the used cartridges must still be sent out to another facility, or back to the manufacturer, for refilling since it requires disassembly of its components.

Accordingly, a number of devices have been proposed for facilitating the opening of such cartridges in order to gain access to its interior to replenish the toner and recycle such cartridges for reuse by the consumer. Examples of such devices are shown in U. S. patents 5,223,068 and 5,407,518 to Baley and in patent 5,657,678 to Cohen. By opening the cartridge along an existing seam as shown in the prior patents the cartridge will be separated into its two major components which will have to be sealed together after the cartridge is refilled with toner. In addition covering seals, used to prevent inadvertent dispensing of toner until the cartridge is placed in use, will also have to be replaced.

Toner cartridges of the type shown and described in the above referenced patents used for dispensing fine powder toner in office copying machines typically consist

of two major components. One of the major components is a generally elongated housing or hopper having a generally V-shaped cross section. The open end of the hopper forms a rectangularly shaped opening. The rectangle is defined by the top surfaces of the side and end walls of the hopper. These top surfaces usually protrude to form a flange, thereby forming ledges on flanged surfaces. The other major component is a generally planar dispensing cover which rests on top of the rectangular opening and thus encloses the hopper. The cover typically has a dispensing mechanism, which may include an opening with dispensing rollers and other hardware for proper dispensing of the toner when the cartridge is placed in use. A seal is usually positioned between the flanged surfaces of the hopper and the dispensing cover in order to insure a seal between the surfaces of the cover and the flanged surfaces of the hopper. Once the hopper is filled with toner powder the dispensing cover is adhered to or otherwise sealed with the hopper thus retaining the toner within the hopper and permitting it to be dispensed through the dispensing mechanism in the cover. The components for cartridges of this type are usually made of a polymeric material such as ABS plastic, or PVC resin. The dispenser cover is usually sealed to the top surfaces of the hopper using a compatible adhesive or a welding technique. Once the toner material carried within the hopper is depleted the cartridge becomes useless unless it can be"opened"by removing the dispenser cover from the top side and end wall surfaces of the hopper so that the hopper can be refilled for reuse. In order for the cartridge to become usable again after being refilled, the dispenser cover must be resealed onto the top side and end wall surfaces of the hopper in order to prevent leakage of the refilled toner.

Prior techniques for resealing the dispenser cover onto the top side and end wall surfaces of the hopper have included applying a hot melt glue in a bead along the top side and end wall surfaces of the hopper; using short metal clips spaced apart to hold the cover in place on the top surface of the hopper, or using elongated rail type clips which extend the length of the top surface of the hopper for holding the cover in place. Other means of sealing cartridge components together have included the use of acrylic adhesives or ultrasonic welding. None of these prior sealing techniques are satisfactory. The use of hot melt glues or acrylic adhesives spread along the top surfaces of the hopper present a number of problems. First, it is difficult to apply a bead of hot melt glue or acrylic adhesive only to the surfaces to be adhered together without interfering with the proper placement of a piece of film (the cover seal) typically positioned over a dispensing opening in the dispenser cover used to seal the dispensing opening until the cartridge is ready for reuse. The film is usually required to be removed before using the cartridge. In order to accomplish the application of such adhesives effectively, costly and complicated traveling devices must be used to uniformly dispense the adhesive in a consistent bead in the correct locations. In addition, the use of an adhesive requires that the process be completed in a very short period of time to avoid having the adhesive set prematurely. Accordingly, the components to be sealed must be accurately positioned before the adhesive begins to harden. Operating in such a short time period invariably results in errors.

The use of short metal clips or elongated clips has also been found to be unsatisfactory. Such clips require that a gasket made of closed cell foam strips be placed between the parts to be secured together in order to prevent toner from leaking between

the assembled components. Surfaces usually have high and low spots and such an extensive use of gaskets to seal all of the mating surfaces of the hopper and the cover does not always ensure against leakage. Considerable time and effort is required to properly align and position such foam gaskets. If the foam gasket is not properly cleaned prior to the parts being reassembled, toner might tend to migrate through the gasket creating undesirable leaks. Even if the difficulties of using foam gaskets are overcome, the use of clips can cause damage or deformity of the cartridge along the toner applicator rollers thus resulting in poor print quality. The use of clips also causes problems when attempting to reuse a cartridge in an existing office copying machine. A clip placed in a specific area of the cartridge along the top surface of the hopper may not allow the reassembled toner cartridge to be correctly positioned in the copier. Misalignment of the cartridge within the copier will result in poor print quality. In addition clips may fall off the cartridge resulting in damage to the copy machine or may cause physical harm to a user as they frequently have sharp edges. Such clips also create an unsightly appearance.

Finally, ultrasonic welding techniques require elaborate and expensive welding equipment which while effective for certain types of materials are usually not cost effective and can only be used on level surfaces.

OBJECTS OF THE INVENTION It is accordingly a general object of the present invention to overcome the disadvantages of the foregoing sealing methods and to provide a method and means for sealing component parts, whether they have even or uneven surfaces, together in a quick, convenient and inexpensive manner.

It is another general object of the invention to provide a method of sealing components made or constructed of any materials together which permits easy and rapid unsealing of the same components.

A further object of the invention is to provide a method for sealing components together which overcomes the need for the use of a foam gasket.

A further more specific object of the present invention is to provide a quick and convenient method for resealing the major components of toner cartridges together after they have been separated to allow refilling of the cartridge with new toner material so that the cartridge may be reused.

In one embodiment of the invention, a method of sealing components together is accomplished by placing the components adjacent to each other, interposing an electrically resistive wire between the parts and passing an electric current through the wire to cause the wire to increase in temperature and soften the adjacent surfaces of the parts to be joined so that they become welded together. In an alternative embodiment, the wire is coated with an adhesive which will soften upon passing the electric current through the wire causing it to bond with the surface of the parts to be joined.

Yet a further object of the invention is to provide an electrically resistive wire coated with a hot melt adhesive so that when an electric current passes through the wire the adhesive will melt.

Other objects, features and advantages of the invention will be apparent from the description hereinafter.

BRIEF SUMMARY OF THE INVENTION The invention is directed to a method for sealing component parts together by placing the component parts adjacent to each other, interposing an electrically resistive wire between the parts, and passing an electric current through the wire to cause the temperature of the wire to rise. When sealing component parts made of certain types of materials, having a relatively low softening point, such as plastics, the component parts are urged toward each other so that when the wire becomes heated it will cause the plastic component part in contact with the wire to soften. By applying a force to the softened parts in order to urge them into contact with each other, the softened parts will be sealed together. Removing the electric current from the wire will allow the wire and the parts to cool so that the softened contact surfaces will harden forming a seal between them. When sealing component parts made of other types of materials, such as glass, metal or other materials having relatively high softening points, the wire will have a coating of hot melt glue which will soften and adhere to the surfaces to be bonded when the electrically resistive wire is heated by passing a current through it. The hot melt glue coating can also be used when bonding low softening point materials, such as plastics.

BRIEF DESCRIPTION OF THE DRAWING Figure 1 is a partially exploded perspective view illustrating the major components of a toner cartridge to be sealed together using the method of the present invention;

Figure 2 is a sectional view taken along lines 11-11 of figure 1 showing one embodiment of the present invention; Figures 3A, 3B, 3C, 3D, 3E, 3F, 3G, 3H and 31 are plan views of one of the major components of the toner cartridge shown in figure 1 and illustrating nine different arrangements for practicing the present invention; Figure 4 is a sectional view similar to figure 2 showing an alternative embodiment of the present invention; Figure 5 is a perspective view illustrating one embodiment of a resistive wire with a coating of hot melt glue; Figure 6 is a perspective view illustrating an alternative embodiment of a resistive wire coated with a hot melt glue; Figures 7,8,9 and 10 are plan views illustrating further embodiments of a resistive wire coated with hot melt adhesive; and Figure 11 is perspective view of a toner cartridge illustrating the major components of the toner cartridge shown in figure 1 after being resealed together using the method of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As noted above, the present invention will be described in connection with the sealing and resealing of toner cartridge components. Figure 1 illustrates a typical toner cartridge 10 of the type described in patents 5,223,068,5,407,518 and 5,657,678. The cartridge is formed of two major components, a toner hopper 11 and a dispensing cover 12.

Cover 12 includes a toner dispenser mechanism 13. Hopper 11 has a generally V-shaped cross section as illustrated in figure 2. The hopper has an interior region 14 for housing toner material. The interior region 14 is defined by end walls 15 and 16 and elongated side walls 17 which are integral with each other. The top edge surfaces of end walls 15 and 16 form top ledges or flanges 25 and 26 respectively. The elongated top edge surface of side walls 17 forms elongated top ledges or flanges 27. When assembling cover 12 with hopper 11 it is critical that a narrow elongated peripheral border area 18, illustrated in dotted line, of the cover 12 be sealed with the elongated top ledges 27 in order to prevent undesirable leakage of toner from the hopper 11 when the cartridge is placed in use. The top ledges 25 and 26 are similarly sealed with the narrow peripheral end borders 19 of cover 12, or the space between them can be filled with a gasket in order to prevent leakage of toner from the ends. When the cartridge is placed into use in an office copier machine it will be positioned such that the hopper 11 is oriented in a manner to permit the toner to be dispensed through the dispensing mechanism 13 using gravity to assist in the dispensing action. Accordingly, it is highly undesirable if any toner were to leak or otherwise pass between perimeter surfaces 18 or 19 of the cover 12 and the top ledges 25,26 or 27 of hopper 11. Manufacturers have used a variety of techniques for sealing the cover 12 to the hopper 11. As noted above, these techniques range from applying an adhesive to the surfaces of perimeters 18 and 19 and to the surfaces of ledges 25,26,27, to using expensive ultrasonic welding techniques to weld these surfaces together. For the reasons

noted above, these various techniques have been either unsatisfactory or expensive to implement.

The present invention involves the use of an electrically resistive wire 20 positioned between the surfaces of the components to be joined. Depending on the materials of construction of the components to be bonded, the wire 20 will be either bare or may be coated with a hot melt adhesive, as described in further detail below. In the case of bonding components made of polymeric materials which have a relatively low softening point, a bare wire can be used. In figure 1, electric wire 20 is shown as being placed along one of the top ledges 27. When cover 12 is positioned for assembly with hopper 11, wire 20 will be positioned between the ledge 27 and perimeter 18 of cover 12 as more clearly seen in figure 2. In operation, a device, such as a"C"clamp schematically illustrated in figure 2 as reference numeral 21 or any other kind of device for applying or exerting pressure on the cover 12 and hopper 11 to urge them toward each other, is positioned so as to apply a force to cover 12 and hopper 11 in the areas of perimeter 18 and ledge 27 respectively in order to urge the facing surfaces together so that wire 20 will be in physical contact with the surface of ledge 27 and the surface of cover 12 in the area of perimeter 18.

Upon passing an electric current through wire 20, diagrammatically indicated by plus and minus signs at opposite ends of the wire, the wire 20 will become heated. In the case, as described herein for bonding polymeric materials, such as the components of the toner cartridge, a bare uncoated wire can be used which when heated will cause the material in the areas of perimeter 18 and ledge 27 to soften. Good results are achieved using a 22 gauge nickel chromium alloy wire, known as nichrome, with an electrical resistance of between 650 and 750 ohms per CMF (circular mill foot) which will heat up to about from 200°F to 400°F after a dwell time of about five seconds with approximately 40 volts

applied across the wire. This will be sufficient to produce an adequate heating. As a result of continued force applied by clamp 21 the softened surfaces will come in contact with each other. Upon removal of the electric current from the bare electric wire, the wire will cool causing the contact areas of cover 12 and ledge 27 to cool and become welded together.

The electric wire whether bare or coated with a hot melt adhesive, can be placed along only one of the longitudinal ledges 27, as illustrated in figure 1, to seal the surface of perimeter 18 with the surface of one of the longitudinal ledges 27. Similarly, a wire 20 can be placed along both longitudinal ledges 27, as illustrated in figure 3A, which will result in sealing cover 12 with hopper 11 along both longitudinal sides. When sealing only the longitudinal ledges 27 with cover 12, the transverse ledges 25 and 26 at the top of end walls 15 and 16 respectively will be sealed using a foam gasket positioned between the cover 12 in the area of perimeter 19 and the transverse ledges 25 and 26.

Alternatively, a wire 30 can be arranged in an L-shaped configuration, such as shown in figure 3B to seal the cover 12 with hopper 11 along one of the longitudinal ledges 27 and one of the transverse ledges 25 or 26. In this case, gaskets will be placed between the facing surfaces of cover 12 and hopper 11 in the areas along the other longitudinal ledge 27 and the other transverse ledge. A U-shaped wire 40, as shown in figure 3C or a rectangular shaped wire 50 shown in figure 3D, can be used to seal all the ledge surfaces of hopper 11 with all the perimeter areas 18,19 of cover 12. Figure 3E illustrates yet a further arrangement of wires 20 for sealing transverse ledges 25 and 26 with perimeter

areas 19 of cover 20; and figure 3F illustrates the use of a U-shaped wire 70 for sealing one of the longitudinal ledges 27 with a perimeter area 18, and the two transverse ledges 25 and 26 with perimeter area 19.

Alternative arrangements of the wire are illustrated in figures 3G, 3H and 3I. In figure 3G wires 80 are placed along the longitudinal ledge 27 in a U-shaped configuration so that both exposed ends, indicated by + and-symbols will be located adjacent each other for convenient placement of connections to a source of electrical voltage. Figures 3H and 31 illustrate other arrangements of wires 81 and 82 for placement along either of the longitudinal and transverse ledges.

While in most cases a traditional wire having a circular cross section, such as indicated in figures 1 and 2, will achieve the purposes of the invention, an electrically resistive wire, which is generally"flat", i. e., one having a cross section with an aspect ratio of at least three to one, such as rectangular wire 60 illustrated in figure 4, may also be used to create a wider or more effective heated zone. Good results are also achieved using a nichrome flat wire having cross section dimensions of 0.008 inches by 0.062 inches.

The use of the electrically resistive wire in the manner described thus avoids the need for a complete perimeter gasket.

An alternative embodiment of the invention is the use of a resistive wire which is coated with a hot melt adhesive such as illustrated in figures 5 and 6. In figure 5, round wire 20 has a coating of hot melt adhesive 22. Figure 6 shows flat wire 60 provided with a coating of hot melt adhesive 23. The hot melt adhesive will be applied to

the wire in a hardened and nonadhesive condition or allowed to harden, before the wire is placed for use. This will allow easy handling of the wire with the adhesive bonded to it.

When using a resistive wire 20 or 60 having a coating of hot melt adhesive, passing an electric current through the wire will cause the wire to become heated resulting in the hot melt adhesive becoming soft to acquire adhesive quality so as to adhere to the components being joined together. When the electric current is removed from the wire, it will rapidly cool causing the hot melt adhesive to set and harden thus bonding the components together.

A wire of the same type as described above will also work well with a hot melt adhesive coating when appropriate voltage is applied to it in order to soften the hot melt adhesive coating to give it an adhesive quality. A wire having such a coating can be used for bonding materials which have a higher softening point than plastics or other polymeric material, but may also be used with polymeric materials, such as the toner cartridge components described above.

A wire, such as wires 90,91,92 and 93 illustrated in figures 7,8,9 and 10 respectively, each coated with hot melt adhesive 22, can be arranged so that the wire is doubled over with both its exposed ends adjacent each other for easy and convenient connection to a source of appropriate voltage. Wires 90,91,92 and 93 in the appropriate shape are coated with adhesive 22 by placing the wire between two sheets of dry adhesive and cutting the adhesive, such as by die cutting, to conform to the shape of the wire.

Once the cover 12 is sealed or bonded to the hopper 11 as illustrated in Figure 11, the ends 29 of the wire 20 can either be clipped or folded over the sealed components into a position so that it will not interfere with the intended use of the cartridge

10 by the ultimate consumer.

Use of the method of the present invention for sealing the major components together through the application of heat applied by the use of an electrically resistive wire permits rapid and easy unsealing of the same components by once again passing an electric current through the wire thus causing the wire to again become heated.

This results in softening the contact surfaces or the hot melt adhesive allowing easy separation of the previously bonded components.

The invention has been described and illustrated in connection with certain preferred embodiments which are illustrative of the principles of the invention. However, it should be understood that various modifications and changes may readily occur to those skilled in the art, and it is not intended to limit the invention to the construction and operation of the embodiments shown and described herein. Accordingly, additional modifications and equivalents may be considered by falling within the scope of the invention as described by the claims herein below.