Title:
WATER BED FRAME
United States Patent 3838470
Abstract:
A water bed frame comprising a generally vertical, mattress confining, side wall member engageable by an edge of a water mattress and having adjacent the top thereof an inwardly projecting horizontal lip engageable with the edge of the mattress to provide a pressure lock between such lip and the mattress edge, which pressure lock serves to hold conventional bed sheets, and blankets if desired, in place. The lipped wall member is preferably a sectional insert disposed between the mattress edge and an upstanding outer side wall of the frame. The insert is preferably sectional and cooperates with the outer side wall to define a rectangle in the case of a rectangular mattress, and a circle in the case of a circular mattress. The insert sections are provided adjacent the bottoms thereof with fillets engageable with the mattress edge adjacent its bottom.
US Patent References:
Rotatably adjustable circular bed
Goodey et al. - September 1958 - 2849729
/3126229.html
Dickerson - March 1964 - 3126229
LIQUID SUPPORT FOR HUMAN BODIES
Hall - June 1971 - 3585356
Rotatably adjustable circular bed
Goodey et al. - September 1958 - 2849729
/3126229.html
Dickerson - March 1964 - 3126229
LIQUID SUPPORT FOR HUMAN BODIES
Hall - June 1971 - 3585356
Application Number:
05/402464
Publication Date:
10/01/1974
Filing Date:
10/01/1973
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
5/678, 5/915
International Classes:
A47C27/08; A47C27/08
Field of Search:
5/345,348,349,350,348WB,322,320 297/452 219/217
Primary Examiner:
Gilliam, Paul R.
Assistant Examiner:
Calvert, Andrew M.
Attorney, Agent or Firm:
Harris, Kern, Wallen & Tinsley
Claims:
I claim as my invention
1. In a frame for a water bed comprising a water mattress and bedding overlying the water mattress and depending over an edge thereof, the combination of:
2. A water bed frame according to claim 1 including an upstanding outer side wall, said wall member being an insert disposed between said outer side wall and the mattress edge, and said lip being below the upper surface of the water mattress and below the top of said outer side wall.
3. A water bed frame according to claim 1 including an upstanding outer side wall, said lip being on said outer side wall, which constitutes said wall member.
4. A water bed frame as set forth in claim 1 including a fillet on said wall member at the bottom thereof.
5. A water bed frame according to claim 1 including an upstanding outer side wall, said wall member comprising a plurality of inserts disposed in generally end-to-end relation and between said outer side wall and the mattress edge.
1. In a frame for a water bed comprising a water mattress and bedding overlying the water mattress and depending over an edge thereof, the combination of:
2. A water bed frame according to claim 1 including an upstanding outer side wall, said wall member being an insert disposed between said outer side wall and the mattress edge, and said lip being below the upper surface of the water mattress and below the top of said outer side wall.
3. A water bed frame according to claim 1 including an upstanding outer side wall, said lip being on said outer side wall, which constitutes said wall member.
4. A water bed frame as set forth in claim 1 including a fillet on said wall member at the bottom thereof.
5. A water bed frame according to claim 1 including an upstanding outer side wall, said wall member comprising a plurality of inserts disposed in generally end-to-end relation and between said outer side wall and the mattress edge.
Description:
BACKGROUND OF INVENTION
The present invention relates in general to water beds and, more particularly, to a frame for confining a water mattress.
Prior art known to me which relates to water bed frames includes the following U.S. Pat. Nos.:
1,012,629 Greusel 1,051,560 Cowles 3,512,191 Wall et al. 3,585,356 Hall 3,689,949 Weinstein et al.
Prior water bed frames cannot utilize conventional, i.e., unfitted, bedding successfully because of the fact that the bedding works loose rapidly in response to the shifting of the water within the mattress caused by movements of a person or persons sitting or lying on the bed. The result is that the bedding, i.e., pad, sheets, blankets, and the like, quickly works loose around the edges of the mattress and becomes a disheveled mess.
Fitted bedding works satisfactorily with a conventional water bed frame, but is extremely difficult to install and remove because of the great weight of a water mattress.
The present invention relates to a water bed frame which overcomes the foregoing and other disadvantages of prior water bed frames.
OBJECTS AND SUMMARY OF INVENTION
With the foregoing background in mind, the primary object of the invention is to provide a water bed frame which does not require fitted bedding and which will securely lock the edges of unfitted bedding in place, irrespective of the movements of a person or persons utilizing the bed.
More particularly, the primary object of the invention is to provide a water bed frame having a side wall member which is engageable by the edge of the water mattress and which is so designed that it cooperates with the water in the mattress to provide a pressure lock for retaining the edges of unfitted bedding, the pressure lock increasing in intensity as the weight on the water mattress increases.
Still more particularly, the basic object of the invention is to provide a water bed frame which includes a generally vertical, mattress confining, side wall member engageable by an edge of a water mattress and provided adjacent the top thereof with an inwardly projecting horizontal lip engageable with the edge of the mattress to provide between such lip and the mattress edge a pressure lock for confining the edges of unfitted bedding. Viewed differently, the inwardly projecting horizontal lip provides therebeneath a cove which receives the edges of the pad, sheets, blankets, and the like, to retain them securely in place.
Preferably, the lipped wall member takes the form of an insert disposed between an upstanding outer side wall of the water bed frame and the mattress edge, which is another object of the invention. However, if desired, the lip mentioned can be formed directly on the outer side wall of the frame.
The invention is applicable to either rectangular or circular water mattresses. If the aforementioned lipped insert is used, it is preferably sectional, being formed in four sections in the case of a rectangular mattress, and any convenient number of sections in the case of a circular mattress. With a rectangular mattress, the four sections may be mitered at the corners, or may simply overlap. In any case, the sections of the insert are disposed generally in end-to-end relation.
The invention is also applicable to a bottomless water bed frame which rests directly on the floor, or to a water bed frame having a bottom wall resting on the floor, or on a pedestal, legs, or the like.
Another important object is to provide the upstanding side wall member with a fillet adjacent the bottom thereof which is engageable by the mattress edge adjacent its bottom. This fillet eliminates any corner space around the bottom of the mattress edge and thus restricts the mattress in this area to prevent sloshing of the water in the mattress. Further, the fillet causes the weight of the mattress to act downwardly on the upstanding side wall member, thereby firmly retaining such member in place in the case of an insert or sectional insert.
The lipped and filleted wall member may be formed of any suitable material, such as molded or extruded plastic, wood, metal, or the like, the same being true in the case where the upstanding outer side wall of the water bed frame itself is the lipped and filleted member.
The foregoing objects, advantages, features and results of the present invention, together with various other objects, advantages, features and results thereof which will be evident to those skilled in the water bed art in the light of this disclosure, may be achieved with the exemplary embodiments of the invention illustrated in the accompanying drawing and described in detail hereinafter.
DESCRIPTION OF DRAWING
In the drawing:
FIG. 1 is a plan view of a rectangular water bed embodying the invention;
FIG. 2 is a plan view of a circular water bed embodying the same;
FIG. 3 is an enlarged, fragmentary sectional view, taken as indicated by the arrowed lines 3--3 of FIGS. 1 and 2, and showing one embodiment of a water bed frame of the invention;
FIGS. 4, 5, 6 and 7 are views similar to FIG. 3, but showing other embodiments of the invention;
FIGS. 8 and 9 are fragmentary plan views showing possible corner arrangements for sectional inserts of the invention in a rectangular water bed frame; and
FIG. 10 is a fragmentary plan view showing abutting insert sections in a circular water bed frame of the invention.
DESCRIPTION OF EXEMPLARY EMBODIMENTS OF INVENTION
FIGS. 1 and 2 of the drawing respectively show rectangular and circular water beds 10 and 12 including rectangular and circular water mattresses 14 and 16 disposed in rectangular and circular frames 18 and 20 of the invention. It will be understood, of course, that while the invention is shown as embodied in rectangular and circular water bed frames 18 and 20, it may be embodied in frames of any desired configuration.
In vertical cross section, the water bed frames 18 and 20 are identical. Consequently, only the water bed frame 18 will be considered in detail.
Referring to FIG. 3 of the drawing, the water bed frame 18 is shown as comprising an upstanding outer side wall 22 which, of course, is rectangular, and which confines the water mattress 14. In the particular construction illustrated, the frame 18 rests directly on a floor 24. However, it may be provided with the bottom wall 26 shown in FIGS. 4, 5, 6 and 7, and may also be provided with the pedestal 28 shown in FIGS. 5, 6 and 7. It will be understood that various types of pedestals and/or legs, not shown, may be substituted for the particular pedestal 28 shown.
The upstanding side wall 22 of the water bed frame 18 is provided around its upper edge with an inwardly projecting horizontal lip 30 providing therebeneath a cove 32. In use, the edge of the water mattress 14 fits into the cove 32, and so does the edge of bedding 34 used in conjunction with the water mattress 14. The bedding 34, which is shown as a single layer for convenience, may comprise a pad, bottom and top sheets, one or more blankets, and the like.
With this construction, the pressure of the water in the mattress 14 holds the edge of the bedding 34 firmly in place within the cove 32. More particularly, the water pressure creates a pressure lock forcing the edge of the bedding 34 against the inner edge and the under side of the lip 30 to hold the bedding firmly in place. This pressure lock is enhanced by the weight of a person or persons sitting or lying on the bed 10. Actually, the greater the weight on the water mattress 14, the more intense this pressure lock is, which is an important feature of the invention.
It will be understood, of course, that those portions of the bedding 34 comprising a pad and a bottom sheet are tucked between the water mattress 14 and the lip 30 along the sides, head and foot of the bed 10. The top sheet and any blanket or blankets are, of course, tucked in only at the foot of the bed, or at the foot and along the sides of the bed, as desired.
Extending along the outer side wall 22 of the water bed frame 18, and preferably secured thereto, is a fillet 36 which eliminates any corner space around the bottom of the mattress edge, and thus restricts the mattress in this area to prevent sloshing of the water in the mattress. Otherwise, the corners between the bottom of the water mattress 14 and the ends and sides thereof would not fit tightly into the corresponding corners of the water bed frame 18, leaving slack which would permit sloshing of the water. The fillet 36 prevents this, which is an important feature.
FIG. 4 shows a water bed frame 38 which is very similar to the water bed frame 18, and which includes an upstanding outer side wall 40 secured to the bottom wall 26. In this case, the frame 38 is provided with an inwardly projecting horizontal lip 42 forming part of a member 44 which is secured to the top of the side wall 40 and which extends outwardly therefrom also to provide a seating space around the periphery of the water bed frame 38. The lip 42 operates in the same way as the lip 30, so that no further description is necessary. The water bed frame 38 also includes a fillet 46 corresponding to the fillet 36 and performing the same function.
Turning now to FIG. 5 of the drawing, illustrated therein is a water bed frame 48 which includes an upstanding outer side wall 50 secured to the bottom wall 26. Inserted between the water mattress 14 and the side wall 50 is an insert 52 comprising a side wall member 54 having at the top and bottom thereof an inwardly projecting horizontal lip 56 and a fillet 58, respectively. The lip 56 corresponds to the lip 30 and operates in the same way, so that no further description is required. The fillet 58 performs the same function as the fillet 36, and performs the additional function of causing the weight of the edge of the water mattress 14 to hold the insert 52 down against upward movement due to movements of a person or persons on the water mattress 14.
Referring to FIG. 6 of the drawing, shown is a water bed frame 60 which includes an upstanding outer side wall 62 secured to the bottom wall 26. Disposed between the side wall 62 and the water mattress 14 is an insert 64, which may be made of plastic, or any suitable material, provided adjacent its top with an inwardly projecting horizontal lip 66, and adjacent its bottom with an inwardly projecting fillet 68. The lip 66 and the fillet 68 perform basically the same functions as the lip 30 and the lip 36 described previously. In the case of the lip 66, it projects downwardly, as well as inwardly, to provide an undercut cove 70, which further enhances the pressure lock clamping the edge of the bedding 34 between the water mattress 14 and the insert 64.
FIG. 7 of the drawing illustrates a water bed frame 72 having an upstanding side wall 74 secured to the bottom wall 76. A molded or extruded plastic insert 76 is disposed between the side wall 74 and the water mattress 14, and includes a lip 78 and a fillet 80, the lip 78 providing an undercut cove 82 similar to the cove 70. It is thought that the operation of this embodiment of the invention will be clear without further explanation.
It will be understood, of course, that the various lips and fillets shown in FIGS. 3 to 7 extend all the way around the corresponding water bed frames. In FIGS. 5 to 7, the respective inserts 52, 64 and 76 are sectional and disposed at least generally in end-to-end relation. More particularly, in the rectangular water bed 10, the inserts 52, 64 and 76 each comprises four sections respectively extending along the sides and ends of the corresponding water bed frame. FIG. 8 shows, for example, the sectional insert 64 as composed of insert sections 84 which are mitered at the corners of the frame 60. FIG. 9 shows the insert 64 composed of sections 86 arranged in an unmitered relation, with an end of one section 86 abutting a side of another. This makes a very simple installation since no mitering is required. FIG. 10 shows the circular water bed 12 with the insert 64 of FIG. 6 divided into sections 88 arranged in end-to-end, abutting relation at 90. As previously stated, the circular water bed 12 may be provided with any convenient number of the insert sections 88. Similar considerations are applicable if the inserts 52 or 76 of FIGS. 5 or 7 are used.
The various inserts hereinbefore described have an important advantage in that they can be added to an existing bed without disturbing the ensemble of bed frame and filled mattress. Therefore, the old frame is not rendered obsolete, but the invention is added thereto. The installation requires no mechanical skill, no tools, no fastening devices or adhesives, and no altering of the structure. The nature of the invention does not impair the design appearance since, when the inserts are in place, they are completely out of sight. The inserts are merely pushed into position between the mattress liner and the bed frame and remain stationary (no moving parts to wear). Releasing the bedding is easy. You merely press the mattress by any top edge downward as you pull out the bedding. The lock works on all liquid mattresses, or other liquid filled articles in frames.
Although exemplary embodiments of the invention have been disclosed for illustrative purposes, it will be understood that various changes, modifications and substitutions may be incorporated in such embodiments without departing from the invention as hereinafter claimed.
The present invention relates in general to water beds and, more particularly, to a frame for confining a water mattress.
Prior art known to me which relates to water bed frames includes the following U.S. Pat. Nos.:
1,012,629 Greusel 1,051,560 Cowles 3,512,191 Wall et al. 3,585,356 Hall 3,689,949 Weinstein et al.
Prior water bed frames cannot utilize conventional, i.e., unfitted, bedding successfully because of the fact that the bedding works loose rapidly in response to the shifting of the water within the mattress caused by movements of a person or persons sitting or lying on the bed. The result is that the bedding, i.e., pad, sheets, blankets, and the like, quickly works loose around the edges of the mattress and becomes a disheveled mess.
Fitted bedding works satisfactorily with a conventional water bed frame, but is extremely difficult to install and remove because of the great weight of a water mattress.
The present invention relates to a water bed frame which overcomes the foregoing and other disadvantages of prior water bed frames.
OBJECTS AND SUMMARY OF INVENTION
With the foregoing background in mind, the primary object of the invention is to provide a water bed frame which does not require fitted bedding and which will securely lock the edges of unfitted bedding in place, irrespective of the movements of a person or persons utilizing the bed.
More particularly, the primary object of the invention is to provide a water bed frame having a side wall member which is engageable by the edge of the water mattress and which is so designed that it cooperates with the water in the mattress to provide a pressure lock for retaining the edges of unfitted bedding, the pressure lock increasing in intensity as the weight on the water mattress increases.
Still more particularly, the basic object of the invention is to provide a water bed frame which includes a generally vertical, mattress confining, side wall member engageable by an edge of a water mattress and provided adjacent the top thereof with an inwardly projecting horizontal lip engageable with the edge of the mattress to provide between such lip and the mattress edge a pressure lock for confining the edges of unfitted bedding. Viewed differently, the inwardly projecting horizontal lip provides therebeneath a cove which receives the edges of the pad, sheets, blankets, and the like, to retain them securely in place.
Preferably, the lipped wall member takes the form of an insert disposed between an upstanding outer side wall of the water bed frame and the mattress edge, which is another object of the invention. However, if desired, the lip mentioned can be formed directly on the outer side wall of the frame.
The invention is applicable to either rectangular or circular water mattresses. If the aforementioned lipped insert is used, it is preferably sectional, being formed in four sections in the case of a rectangular mattress, and any convenient number of sections in the case of a circular mattress. With a rectangular mattress, the four sections may be mitered at the corners, or may simply overlap. In any case, the sections of the insert are disposed generally in end-to-end relation.
The invention is also applicable to a bottomless water bed frame which rests directly on the floor, or to a water bed frame having a bottom wall resting on the floor, or on a pedestal, legs, or the like.
Another important object is to provide the upstanding side wall member with a fillet adjacent the bottom thereof which is engageable by the mattress edge adjacent its bottom. This fillet eliminates any corner space around the bottom of the mattress edge and thus restricts the mattress in this area to prevent sloshing of the water in the mattress. Further, the fillet causes the weight of the mattress to act downwardly on the upstanding side wall member, thereby firmly retaining such member in place in the case of an insert or sectional insert.
The lipped and filleted wall member may be formed of any suitable material, such as molded or extruded plastic, wood, metal, or the like, the same being true in the case where the upstanding outer side wall of the water bed frame itself is the lipped and filleted member.
The foregoing objects, advantages, features and results of the present invention, together with various other objects, advantages, features and results thereof which will be evident to those skilled in the water bed art in the light of this disclosure, may be achieved with the exemplary embodiments of the invention illustrated in the accompanying drawing and described in detail hereinafter.
DESCRIPTION OF DRAWING
In the drawing:
FIG. 1 is a plan view of a rectangular water bed embodying the invention;
FIG. 2 is a plan view of a circular water bed embodying the same;
FIG. 3 is an enlarged, fragmentary sectional view, taken as indicated by the arrowed lines 3--3 of FIGS. 1 and 2, and showing one embodiment of a water bed frame of the invention;
FIGS. 4, 5, 6 and 7 are views similar to FIG. 3, but showing other embodiments of the invention;
FIGS. 8 and 9 are fragmentary plan views showing possible corner arrangements for sectional inserts of the invention in a rectangular water bed frame; and
FIG. 10 is a fragmentary plan view showing abutting insert sections in a circular water bed frame of the invention.
DESCRIPTION OF EXEMPLARY EMBODIMENTS OF INVENTION
FIGS. 1 and 2 of the drawing respectively show rectangular and circular water beds 10 and 12 including rectangular and circular water mattresses 14 and 16 disposed in rectangular and circular frames 18 and 20 of the invention. It will be understood, of course, that while the invention is shown as embodied in rectangular and circular water bed frames 18 and 20, it may be embodied in frames of any desired configuration.
In vertical cross section, the water bed frames 18 and 20 are identical. Consequently, only the water bed frame 18 will be considered in detail.
Referring to FIG. 3 of the drawing, the water bed frame 18 is shown as comprising an upstanding outer side wall 22 which, of course, is rectangular, and which confines the water mattress 14. In the particular construction illustrated, the frame 18 rests directly on a floor 24. However, it may be provided with the bottom wall 26 shown in FIGS. 4, 5, 6 and 7, and may also be provided with the pedestal 28 shown in FIGS. 5, 6 and 7. It will be understood that various types of pedestals and/or legs, not shown, may be substituted for the particular pedestal 28 shown.
The upstanding side wall 22 of the water bed frame 18 is provided around its upper edge with an inwardly projecting horizontal lip 30 providing therebeneath a cove 32. In use, the edge of the water mattress 14 fits into the cove 32, and so does the edge of bedding 34 used in conjunction with the water mattress 14. The bedding 34, which is shown as a single layer for convenience, may comprise a pad, bottom and top sheets, one or more blankets, and the like.
With this construction, the pressure of the water in the mattress 14 holds the edge of the bedding 34 firmly in place within the cove 32. More particularly, the water pressure creates a pressure lock forcing the edge of the bedding 34 against the inner edge and the under side of the lip 30 to hold the bedding firmly in place. This pressure lock is enhanced by the weight of a person or persons sitting or lying on the bed 10. Actually, the greater the weight on the water mattress 14, the more intense this pressure lock is, which is an important feature of the invention.
It will be understood, of course, that those portions of the bedding 34 comprising a pad and a bottom sheet are tucked between the water mattress 14 and the lip 30 along the sides, head and foot of the bed 10. The top sheet and any blanket or blankets are, of course, tucked in only at the foot of the bed, or at the foot and along the sides of the bed, as desired.
Extending along the outer side wall 22 of the water bed frame 18, and preferably secured thereto, is a fillet 36 which eliminates any corner space around the bottom of the mattress edge, and thus restricts the mattress in this area to prevent sloshing of the water in the mattress. Otherwise, the corners between the bottom of the water mattress 14 and the ends and sides thereof would not fit tightly into the corresponding corners of the water bed frame 18, leaving slack which would permit sloshing of the water. The fillet 36 prevents this, which is an important feature.
FIG. 4 shows a water bed frame 38 which is very similar to the water bed frame 18, and which includes an upstanding outer side wall 40 secured to the bottom wall 26. In this case, the frame 38 is provided with an inwardly projecting horizontal lip 42 forming part of a member 44 which is secured to the top of the side wall 40 and which extends outwardly therefrom also to provide a seating space around the periphery of the water bed frame 38. The lip 42 operates in the same way as the lip 30, so that no further description is necessary. The water bed frame 38 also includes a fillet 46 corresponding to the fillet 36 and performing the same function.
Turning now to FIG. 5 of the drawing, illustrated therein is a water bed frame 48 which includes an upstanding outer side wall 50 secured to the bottom wall 26. Inserted between the water mattress 14 and the side wall 50 is an insert 52 comprising a side wall member 54 having at the top and bottom thereof an inwardly projecting horizontal lip 56 and a fillet 58, respectively. The lip 56 corresponds to the lip 30 and operates in the same way, so that no further description is required. The fillet 58 performs the same function as the fillet 36, and performs the additional function of causing the weight of the edge of the water mattress 14 to hold the insert 52 down against upward movement due to movements of a person or persons on the water mattress 14.
Referring to FIG. 6 of the drawing, shown is a water bed frame 60 which includes an upstanding outer side wall 62 secured to the bottom wall 26. Disposed between the side wall 62 and the water mattress 14 is an insert 64, which may be made of plastic, or any suitable material, provided adjacent its top with an inwardly projecting horizontal lip 66, and adjacent its bottom with an inwardly projecting fillet 68. The lip 66 and the fillet 68 perform basically the same functions as the lip 30 and the lip 36 described previously. In the case of the lip 66, it projects downwardly, as well as inwardly, to provide an undercut cove 70, which further enhances the pressure lock clamping the edge of the bedding 34 between the water mattress 14 and the insert 64.
FIG. 7 of the drawing illustrates a water bed frame 72 having an upstanding side wall 74 secured to the bottom wall 76. A molded or extruded plastic insert 76 is disposed between the side wall 74 and the water mattress 14, and includes a lip 78 and a fillet 80, the lip 78 providing an undercut cove 82 similar to the cove 70. It is thought that the operation of this embodiment of the invention will be clear without further explanation.
It will be understood, of course, that the various lips and fillets shown in FIGS. 3 to 7 extend all the way around the corresponding water bed frames. In FIGS. 5 to 7, the respective inserts 52, 64 and 76 are sectional and disposed at least generally in end-to-end relation. More particularly, in the rectangular water bed 10, the inserts 52, 64 and 76 each comprises four sections respectively extending along the sides and ends of the corresponding water bed frame. FIG. 8 shows, for example, the sectional insert 64 as composed of insert sections 84 which are mitered at the corners of the frame 60. FIG. 9 shows the insert 64 composed of sections 86 arranged in an unmitered relation, with an end of one section 86 abutting a side of another. This makes a very simple installation since no mitering is required. FIG. 10 shows the circular water bed 12 with the insert 64 of FIG. 6 divided into sections 88 arranged in end-to-end, abutting relation at 90. As previously stated, the circular water bed 12 may be provided with any convenient number of the insert sections 88. Similar considerations are applicable if the inserts 52 or 76 of FIGS. 5 or 7 are used.
The various inserts hereinbefore described have an important advantage in that they can be added to an existing bed without disturbing the ensemble of bed frame and filled mattress. Therefore, the old frame is not rendered obsolete, but the invention is added thereto. The installation requires no mechanical skill, no tools, no fastening devices or adhesives, and no altering of the structure. The nature of the invention does not impair the design appearance since, when the inserts are in place, they are completely out of sight. The inserts are merely pushed into position between the mattress liner and the bed frame and remain stationary (no moving parts to wear). Releasing the bedding is easy. You merely press the mattress by any top edge downward as you pull out the bedding. The lock works on all liquid mattresses, or other liquid filled articles in frames.
Although exemplary embodiments of the invention have been disclosed for illustrative purposes, it will be understood that various changes, modifications and substitutions may be incorporated in such embodiments without departing from the invention as hereinafter claimed.