Abstract:
An osmophore-pacifier. The osmophore-pacifier contains an odorant. When the osmophore-pacifier is sucked by an infant, it releases an odor which stimulates sucking behavior in the infant. The osmophore-pacifier includes a nipple, a shield portion, a matrix containing the odorant, and an air channel for releasing the odor. The odorant may be replaced with a different type of odorant in order to determine which odor stimulates continued sucking of the osmophore-pacifier, to promote sucking behavior, and to calm or soothe an infant in a state of agitation or pain.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 09/516,372, filed on Mar.1, 2000, now abandoned, and claims the benefit of priority of U.S. Provisional Application No. 60/122,333, filed on Mar. 2, 1999, the entire disclosure of which is incorporated by reference into this application. 
    
    
     FIELD OF THE INVENTION 
     The present invention is directed to infant pacifiers. More particularly, the present invention is directed to infant pacifiers which stimulate sucking behavior in infants. 
     BACKGROUND OF THE INVENTION 
     Many babies do not have fully developed or coordinated sucking and swallowing reflexes. Theses deficiencies may exist, for example, with tube-fed or premature babies. The use of conventional nipples and pacifiers is insufficient to stimulate sucking to improve these capacities. These deficiencies can prevent babies from obtaining the proper nourishment needed for healthy growth. 
     The promotion of non-nutritive sucking behavior in infants has been used as a remedy for the deficiencies. It is considered a valid therapeutic objective, because it accelerates recovery of feeding reflexes and promotes gastric motility. Past attempts to stimulate sucking have incorporated tactile stimuli, taste stimuli, flavored or scented pacifiers, or any combination of the three. 
     Nevertheless, taste stimuli have not proved to be therapeutically successful. In addition, certain pacifiers which provide some flavor or scent to the infant, but which are not dependent on the sucking activity of the infant, do not act as direct stimuli. Thus, there is a need to improve on conventionally used tactile stimuli and other flavors or scents presently used to encourage infant sucking. 
     SUMMARY OF THE INVENTION 
     To meet this and other needs, and in view of its purposes, the present invention provides a pacifier including a mechanism for generating an odor which stimulates sucking behavior. As an infant user sucks on the pacifier, the sucking causes an odor to be generated from the pacifier in a location proximate to the infant&#39;s nostrils. The odor is preferably a pleasant odor, which encourages the infant to continue sucking. The infant is operatively conditioned to suck on the pacifier so that it produces the odor, thus encouraging the infant&#39;s sucking and feeding reflexes. 
     In one embodiment of the present invention, the pacifier contains a nipple which, when sucked, causes the pacifier to release an odor which stimulates sucking behavior in, for example, an infant. The odor release may be prompted by a pressure differential in the pacifier, fluid flow or evaporation, any combination of those factors, or any other suitable mechanism which causes the odor to be released when the pacifier is sucked. 
     In a preferred embodiment of the present invention, the pacifier contains a housing, a shield, an odorant (i.e., odor source), air channels, and a nipple which, along with the housing, creates an airspace. When the nipple is sucked by an infant, the airspace is reduced which forces air across the odorant, thus picking up the scent. The odor proceeds through the air channels to outside of the shield where the scent is detected by the infant. 
     In another embodiment of the present invention, the pacifier is used in a method of diagnosing what odor or odors are pleasing. The pacifier can be used, according to this method, to stimulate feeding reflexes in infants by testing the pacifier using different odors and observing whether different odors act as sucking stimuli. In yet another embodiment of the present invention, the pacifier is used in a method of operant-conditioning an infant to stimulate feeding reflexes by providing the infant with the pacifier, such that sucking of the pacifier by the infant produces a pleasant odor for the infant, and allowing the infant to continue sucking. In a further embodiment of the present invention, the pacifier is used to calm or soothe an infant in a state of agitation or pain. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary, but are not restrictive, of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The invention is best understood from the following detailed description when read in connection with the accompanying drawing. It is emphasized that, according to common practice, the various features of the drawing are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. Included in the drawing are the following figures: 
     FIG. 1 if a cross-sectional view of a first embodiment of the pacifier of the present invention; 
     FIG. 2 is a front view of the first embodiment of the pacifier of the present invention; 
     FIG. 3 is a cross-sectional view of a second embodiment of the pacifier of the present invention; 
     FIG. 4 is a cross-sectional view of a third embodiment of the pacifier of the present invention; 
     FIG. 5 is a cross-sectional view of a fourth embodiment of the pacifier of the present invention; 
     FIG. 6A is a cross-sectional view of a preferred embodiment of the pacifier of the present invention; and 
     FIG. 6B is a frontal elevational view of the pacifier shown in FIG.  6 A. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Certain terminology is used in the following description for convenience only and is not intended to limit the scope of the invention in any way. The words “right,”“left,”“lower, ” and “upper” designate directions in the drawing s to which reference is made. The words “inwardly” and “outwardly” refer to directions towards and away from, respectively, the geometric center of the pacifier and designated parts of the pacifier in accordance with the present invention. The terminology includes the words noted above as well as derivatives of those words and words of similar import. 
     The pacifier of the present invention is intended to be used primarily in the treatment and prevention of feeding difficulty in infants. Use of the pacifier of the present invention is based on an operant-conditioning principle, i.e., using an odor as a reward for sucking behavior. This strategy is based on the premise that an olfactory cue can act as a positive reinforcer for sucking behavior because infants are known to be oriented to olfactory stimuli. The characteristics of neonatal olfaction that make it a good choice for promoting non-nutritive sucking include: (1) there is strong evidence that infants normally learn by using olfactory cues, and that certain olfactory sensations have intrinsic hedonic value for neonates; (2) olfactory stimuli are known to play an important role in organizing and orienting oral appetite behavior in infants; and (3) the potential for toxicity from repeated exposure to a purely olfactory stimulus is negligible. 
     Thus, the present invention is directed to a pacifier incorporating an olfactory stimulus (odor), optionally with a tactile stimulus (nipple), to encourage sucking behavior in infants. The two combined types of stimuli are more effective than conventionally used tactile stimuli alone. The olfactory stimulus is especially needed in those infants with a weak response to tactile stimuli. Further, the response of an infant to the olfactory stimulus may provide information on an infant&#39;s flavor preferences and an approximate restoration of odor experience to tube-fed infants may be beneficial beyond stimulating non-nutritive sucking behavior. 
     Referring to the drawing, in which like numbers indicate like elements throughout, there is shown in FIGS. 1 and 2 an osmophore-pacifier  10  in accordance with the present invention. The osmophore-pacifier  10  includes a nipple  12  and a shield  14  generally similar in shape to that of a typical pacifier. The nipple  12  is hollow and includes an exterior wall  16  that is placed in the infant&#39;s mouth. The remainder of the osmophore-pacifier  10  is extra-oral. The shield  14  is attached to an outer perimeter  18  of an open end of the nipple  12  and is large enough to prevent the shield  14  from being inserted into the infant&#39;s mouth. The shield  14  has a superior edge  20  which, when the osmophore-pacifier  10  is properly inserted into the infant&#39;s mouth, is located between the infant&#39;s upper lip and nostrils. 
     A housing  22  is provided on the shield  14  distal from the nipple  12 . The housing  22  and the shield  14  generally comprise a base  23 . The housing  22  may be separate from the shield  14  or formed within the shield  14 . The housing  22  encloses an odorant reservoir  24 , a wick chamber  26 , and an osmophore  28 . Preferably, the housing  22  is made of plastic, but those skilled in the art will understand that other suitable materials can be used. 
     The outward appearance of the osmophore-pacifier  10  is not much different than that of a typical pacifier, with the exception that the extra-oral part of the osmophore-pacifier  1 O is somewhat larger and deeper than the typical pacifier due to the odorant reservoir  24 . An opening is located through the housing  22  proximate the superior edge  20  of the shield  14  so that, when the osmophore-pacifier  10  is in the infant&#39;s mouth, the opening is located proximate to the infant&#39;s nose. The opening may be covered by a removable grid  30  or partially covered by a removable panel to retain the osmophore  28  in the osmophore-pacifier  10 . 
     Preferably, the reservoir  24  inside the housing  22  is funnel-shaped, tapering to a small aperture  32  which is located at the bottom of the reservoir  24  when the osmophore-pacifier  10  is in use, as shown in FIG.  1 . An odorant solution  34  is contained within the reservoir  24 . The shape of the reservoir  24  and the small size of the aperture  32  minimize the reservoir-draining effect of the hydrostatic pressure which is naturally exerted by the odorant solution  34  on the area of the aperture  32  compared to the effect of the surface tension of the odorant solution  34  at the aperture  32 . This configuration tends to keep the odorant solution  34  within the reservoir  24 . Preferably, the capacity of the reservoir  24  is less than three milliliters, although the capacity of the reservoir  24  can be equal to or greater than three milliliters. The reservoir  24  includes a vent  36  located on the housing  22  that vents the reservoir  24  to the surrounding atmosphere and prevents a negative pressure from being formed in the reservoir  24  as the odorant solution  34  is drawn out. 
     The aperture  32  fluidly connects the reservoir  24  to the wick chamber  26  within the housing  22 . A wick  40  is located in the wick chamber  26 , with a first wick end  42  extending toward the aperture  32 . Preferably, the first wick end  42  is tubular so that capillary action draws the odorant solution  34  in the wick  40 . Preferably, a second end  46  of the wick  40  opens into the osmophore  28 . Preferably, the wick  40  is comprised of material, such as cellulose, silicone, or cogeners of those materials, that maximizes the diffusion or the odorant solution  34  through the wick  40  and along a concentration gradient through capillary action. Moreover, those skilled in the art will realize that other suitable materials can be used. 
     It is preferred that the wick chamber  26  is under 1.0 milliliter in capacity and is separated from the nipple  12  by an elastic diaphragm  44 . The elastic diaphragm  44  and the nipple wall  16  form a chamber within the nipple  12 . The nipple  12  may or may not have a through hole  15  which aids in displacing the diaphragm  44  toward the hole  15  as the infant sucks on the nipple  12 . 
     The wick chamber  26  is separated from the osmophore  28  by a wick seal  29 . The wick  40  extends through the wick seal  29  at a seal hole  31 . The purpose of the wick seal  29  is to form a closed or at least substantially closed wick chamber  26  so that deflection of the diaphragm  44  toward the infant&#39;s mouth, when the infant sucks properly, creates a negative pressure within the wick chamber  26  and draws the odorant solution  34  out of the reservoir  24 . 
     An “osmophore” is commonly defined as a surface from which a volatile compound evaporates and, for the purpose of this application, can include any mechanism for release of a scent or odor. To promote evaporation, an osmophore generally has a large evaporative surface area. The osmophore  28  of the osmophore-pacifier  10  preferably has surface structural characteristics modeled after the osmophore of an insect-pollinated flower, such as an orchid. The osmophore  28  lies on a superior surface  48  of the wick chamber  26  and is continuous with the superior edge  20  of the shield  14  so that a superior surface  50  of the osmophore  28  is in fluid communication with the atmosphere through the opening covered by grid  30  in the housing  22 . The osmophore  28  is thus exposed to the air under the infant&#39;s nose at a fixed distance of preferably less than one centimeter from the infant&#39;s nostrils when the osmophore-pacifier  10  is in the infant&#39;s mouth. The osmophore  28  and the wick  40  are removable from the osmophore-pacifier  10  by first removing the grid  30  over the opening in the housing  22  and then removing the osmophore  28  and the wick  40 . 
     Preferably, the odorant solution  34  which i s contained in the reservoir  24  is made up of an organic acid such as lactic, citric, or butyric acid or vanillan, lactones, or other simple organic compounds found in milk as the active ingredient , although tho se skilled in the art will understand that other active ingredients can be used as the odorant. Any active ingredient that is pleasing to infants such that it stimulates sucking behavior, can be used. The odorant solution  34  can be formed by dissolving organic compounds at fixed concentrations in a aqueous or oil-based solution. 
     To fill the reservoir  24 , the odorant solution  34  is dropped directly onto the superior surface  50  of the osmophore  28  through the opening covered by the grid  30 . Capillary action and the reservoir vent  36  allow the odorant solution  34  to flow in reverse from the osmophore  28 , through the wick  40  and into the reservoir  24 . The vent  36  also allows the reservoir  24  to empty during us e without creating a negative pressure in the reservoir  24 . 
     In operation, the osmophore-pacifier  10  is inserted into the infant&#39;s mouth, with the opening covered by grid  30  on the housing  22  located so that the superior surface  50  of the osmophore  28  is exposed under the infant&#39;s nose. As the infant sucks, the elastic diaphragm  44  is drawn into the hollow of nipple  12 , causing a suction within the housing  22  The suction partially saturates the wick  40  by overcoming the surface tension of the odorant solution  34  at the aperture  32 , drawing the odorant solution  34  into the wick chamber  26  and onto the wick  40 . Passive diffusion of the odorant solution  34  through the wick  40  distributes the odorant solution  34  to the osmophore  28 . 
     The amount of odorant solution  34  delivered to the wick  40  reflects the combined forces of the infant&#39;s suck; the surface tension of the odorant solution  34 ; hydrostatic and electrostatic forces between the wick  40 , the odorant solution  34 , and the housing  22 ; and the distance between the aperture  32  and the wick  40 . This distance can be adjusted according to the power of the infant&#39;s suck. To decrease the amount of odorant solution  34  delivered, the wick  40  can be pulled away from the aperture  32 . In addition, to increase the amount of odorant solution  34  delivered, the wick  40  can be inserted closer to the aperture  32 . 
     The nipple  12  and the diaphragm  44  work together as a pump which is activated by the infant&#39;s suck (not shown) to draw the odorant solution  34  from the reservoir  24  to the wick  40  where it passes through the wick  40  to the superior surface  50  of the osmophore  28 . Evaporation of the odorant solution  34  at the superior surface  50  of the osmophore  28  sets up a chemical concentration gradient which exists until the wick  40  is desaturated with the odorant solution  34 . Once the infant&#39;s suck initiates the flow of odorant solution  34  along the wick  40 , diffusion of the odorant solution  34  through the wick  40  draws the odorant solution  34  toward the superior surface  50  of the osmophore  28  where it evaporates and is inhaled by the infant. 
     Preferably, the kinetic properties of the wick  40 , the osmophore  28 , the odorant solution  34 , and the reservoir  24  are such that the smell of the odorant solution  34  can be detected within one second of the suck. Preferably, the molecular weight of odorants in solution  34  is less than 800 Daltons, although the molecular weight of the odorants  34  can equal or exceed 800 Daltons. Preferably, the smell intensity attenuates to neutral less than three seconds after a single suck. 
     It may be desirable to use an alternate odorant solution if the infant does not respond to the original odorant solution  34  in the osmophore-pacifier  10 . The original odorant solution  34  can be removed from the osmophore-pacifier  10  and replaced by the alternate odorant solution. The original wick  40  and osmophore  28  will be saturated with the original odorants solution  34  and it will be desirable to replace the wick  40  and the osmophore  28  as well. Preferably, the wick  40  and the osmophore  28  can be replaced by removing the grid  30  from the opening in the housing  22 , removing the osmophore  28  and the wick  40  from the wick chamber  26 , inserting a new wick  40  and a new osmophore  28 , and replacing the grid  30  in the opening in the housing  22 . The odorant solution  34  can be emptied from the reservoir  24  by allowing the odorant solution  34  to drain out from the vent  36 . 
     It is preferred that the elastic diaphragm  44  be used to pump the odorant solution  34  from the reservoir  24  to the osmophore  28 . Other mechanisms can be used, however, to perform that function. For example, a pump can expel the odorant solution  34  from the osmophore-pacifier  10 . These mechanisms are powered by deformation of the nipple  12  due to sucking. 
     In addition, although evaporation of a liquid odorant solution is presently preferred, it would be appreciated that an odorant might be provided in solid form and released directly by sublimation to a vapor at ambient or body temperature or as solid particles of a very fine powder and carried away in an air stream generated by sucking the nipple. 
     A second embodiment, which produces an odor without the need for a liquid solution, is shown in FIG.  3 . An osmophore-pacifier  110  comprises a housing  111 , a nipple  112 , a scent chamber  114 , and an osmophore  116 . The scent chamber  114  is accessed by a sealable hatch  120  which is located adjacent to the osmophore  116 . The hatch  120  permits a scent-bearing fibrous material  134  to be inserted into the scent chamber  114 . A one-way valve  122  (e.g., a duck-bill valve) located on the osmophore-pacifier  110  between the scent chamber  114  and the atmosphere allows air to be drawn into the scent chamber  114  upon sucking on the nipple  112 . The one-way valve  122  can be made from material such as pliant silicone, although those skilled in the art will understand that other types of one-way valves and materials can be used. 
     Release of suction (not shown) causes an over-pressure within the scent chamber  114 . The over-pressure is relieved by air escaping from a second one-way valve  126  located adjacent to the osmophore  116 . The air travels through the osmophore  116 , and out of the osmophore-pacifier  110 , where it is inhaled by the infant. As the air travels through the osmophore  116 , the air picks up the odor from the scent-bearing fibrous material  134 . 
     In the third embodiment, shown in FIG. 4, an osmophore-pacifier  200  includes a distensible nipple  202 , a siphon  204 , and osmophore pump  206 , a jet  208 , a sealed pump chamber  210 , and osmophore petals  212 . Preferably, the osmophore  200  is made of all-silicone construction and includes a detachable, porous, sponge-like silicone matrix onto which the odorant is placed (as indicated by arrow  234 ). The petals  212  may be cobbled to increase their surface areas, and are treated intermittently with a volatile liquid odorant, such as a weak mixture of lactate and butyric acids. 
     Sucking by the infant (not shown) on the distensible nipple  202  creates a negative pressure within the lumen  214  of the nipple  202 , which is transmitted by the siphon  204  to the sealed pump chamber  210 . The negative pressure expands the osmophore pump  206  as air flows into its lumen  216  via the jet  208 . Preferably, the osmophore pump  206  is made from thin-walled, balloon-like silicone and the jet  208  is made of rigid, thick-walled silicone. With the release of the infant&#39;s suck, the osmophore pump  206  collapses, expressing air through the jet  208  and obliquely along the osmophore petals  212 . The flume of air expressed from the jet  208  picks up the volatile scent from the osmophore petals  212  and carries the scent toward the infant&#39;s nostrils. It will be appreciated that the lumen  214  and the jet  208  can be coupled through an elastic diaphragm or similar pump elements in other suitable ways known to those skilled in the art. 
     In a fourth embodiment, shown in FIG. 5, the osmophore pacifier  300  includes a distensible nipple  302 , an osmophore bellows  304 , a vapor chamber  306 , a one-way intake valve  308 , and an osmophore  310 . A one-way (e.g., duck-bill) valve  312  lies at the base of the osmophore  310 , which consists of a detachable, porous, sponge-like matrix of silicone or similar material onto which the odorant (indicated by arrow  334 ) is placed. 
     Sucking by the infant (not shown) on the distensible nipple  302  creates a negative pressure in the lumen  314  of the nipple  302 , which is transmitted via contraction of the osmophore bellows  304  to the vapor chamber  306 . Outside air is thereby drawn in to the vapor chamber  306  via the one-way air intake valve  308 . With the release of the infant&#39;s suck, the bellows  304  re-expands, expressing air through the duckbill valve  312  at the base of the osmophore  310 , and creating a current through the osmophore  310 . This current of air becomes scented, and the scent is carried towards the infant&#39;s nose by convection and from the expansion of the bellows  304 . 
     In a preferred embodiment of the present invention, as shown in FIGS. 6A and 6B, the osmophore-pacifier  400  includes a nipple  402  and a hilt  404 , which together generally enclose a lumen (airspace)  406 . The housing  414  of the osmophore-pacifier  400  contains a shield  412  and an opening in which the rear shield  424  is removably secured by a form fit. The ribs  420  of the plug  418  of the rear shield  424  contact the outside of the opening in the housing  414  to form an airtight seal  422 . The rear shield  424  may be attached to the housing  414  by a mechanism other than the plug  418  and pivoted by a hinge or other suitable device to maintain access to the lumen  406 . Alternatively, the rear shield  424  may be a separate part from the housing  414 . In any case, the rear shield  424  may be attached to the opening in the housing  414  at an angle, such as a 45° angle, to further ensure the airtight seal  422 . 
     Inside the lumen  406  and held in the hilt  404 , a sponge or matrix  408 , constructed of cotton, polyethylene, or any other suitable porous material containing an odorant is inserted by removing or pivoting the plug  418  of the rear shield  424  from the housing  414 , placing the matrix  408  in the hilt  404 , and replacing the rear shield  424  to form the airtight seal  422 . 
     When the nipple  402  is placed in an infant&#39;s mouth and the infant (not shown) sucks on the nipple  402 , the lumen  406  is compressed and air is forced across the matrix  408 , picking up the scent, into one or more air channels  410  starting in the hilt  404  and running through the shield  412  and out of the shield  412  through openings  416  in the shield  412 . When the osmophore-pacifier  400  is properly inserted into the infant&#39;s mouth, the openings  416  are located between the infant&#39;s upper lip and nostrils. The scent will further stimulate sucking by the infant and further compression of the air space in the lumen  406 , thus expelling more odor into the nasal area of the infant to continue stimulation. The amount and type of odorant can be adjusted to account for the force which an infant sucks the pacifier, the scents which stimulate an infant, or both. 
     The osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  is used in operant-conditioning of an infant to stimulate feeding reflexes. The infant is provided with the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  so that sucking of the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  by the infant produces a pleasant odor for the infant. The sucking on the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  stimulates and promotes maturation of feeding reflexes. The odor rapidly dissipates, so that, in order to reproduce the odor, the infant must continue sucking on the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400 . By repeatedly sucking on the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  and producing a pleasant odor, the infant is operantly conditioned to associate the pleasant odor with sucking. This increase in non-nutritive sucking behavior is expected to promote healthy feeding reflexes. 
     Initially, it is not known what particular odor or odors may be pleasant to an individual infant. The osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  can be used to diagnose what odor or odors are pleasing or more pleasing to the infant in order to determine which odor or odors can be used to stimulate feeding reflexes. The infant is provided with the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  which contains a particular odorant so that sucking of the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  by the infant produces an odor. If the odor which is produced is pleasing to the infant, the infant will continue to such on the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  to continue producing the odor. If it is determined that the odor produced is pleasing to the infant, the diagnosis determination can be terminated. If the odor which is produced is not pleasing to the infant, the infant will cease sucking on the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400 . The odorant in the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  is then replaced with a new, different odorant, and the process of diagnosing whether the new odor is pleasing to the infant, or whether yet a different odor must be used, is repeated until it is determined which odor promotes sucking of the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  to continue production of that odor. 
     The osmophore-pacifier  10 ,  110 ,  200 , 300 , 400  can be used to treat an infant in a state of agitation or pain. The infant is provided with the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  which contains a particular odorant so that sucking of the osmophore-pacifier  10 ,  110 ,  200 ,  300 ,  400  by the infant produces an odor pleasing to the infant. The infant can then be allowed to continue sucking of the pacifier until the infant is calmed or soothed. 
     The pacifier  10 ,  110 ,  200 ,  300 ,  400  of the resent invention can be further adapted incorporating any suitable individual mechanism used in any embodiment of the present invention. The features of the pacifier  10 ,  110 ,  200 ,  300 ,  400  may be further adjusted to account for behavior of the individual infants. 
     Although illustrated and described above with reference to certain specific embodiments, the present invention is nevertheless not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the spirit of the invention.