INSOLE ASSEMBLIES FOR ADJUSTABLE GIRTH SHOES
Background of the Invention
In order for a shoe to fit properly, it should not only be of the correct length, but also should have width and girth dimensions, particularly in the region where the forepart of the foot is enclosed, that substantially match those of the wearer's foot. As used herein, "girth" is defined as the transverse circumference around the forepart of the foot, typ¬ ically measured at the critical fitting areas including the ball, waist and instep thereof, and is also used to describe the effective inside circumference of the shoe in the same re¬ gions.
Ideally, a customer should be able to purchase a pair of shoes having a separate length and width combination for each foot, reflecting the usual dimensional differences therebe¬ tween, and the size selection should be made from a full range of some nine or more widths for each length. Furthermore, the customer should be supplied with means to adjust the width of such shoe, particularly in the critical flexing ball region, to allow further possible girth adjustments during use, to com¬ pensate for any stretch in the shoe's upper, and for varia¬ tions in stocking thickness, and particularly for the usual dy¬ namic changes in the foot itself, which normally varies over a range of up to two full width sizes diurnally, with even great¬ er variations experienced under a variety of specific physio¬ logical causal factors affecting mainly accumulation of fluid in the extremities such as is often experienced in warm damp weather, in airline flying, and with a variety of illnesses and/or trauma that may produce similar effects.
In practice, however, the so-called 'volume' shoe mar¬ ket, responsible for over 90% of all sales, has found it gener¬ ally uneconomic to offer shoes in more than one or occasional¬ ly two widths, primarily because of the high cost of inventory
at the retail level, and the preferred general policy of carry¬ ing the widest assortment of styles with the minimum assort¬ ment of widths possible. Customers with other than average width feet have a very limited choice, and then usually only at relatively expensive shops, or through mail order opera¬ tions, both of which are better equipped to handle the inven¬ tory problem, although with a considerably more limited choice of styles.
As a result of this situation, it has been accepted that most of all shoes sold provide only an approximate and usually improper fit, particularly in the sensitive and critical ball area where the foot flexes during the stride and where girth adjustment by laces and the like has not proven comfortable or practical.
Attempts to solve this girth adjustment problem by rais¬ ing the height of the insole, as disclosed in U.S. Patent No. 3,442,031, have met with limited acceptance, partly since they usually tend to alter the designed tread of the shoe from that of the last on which it was made, "tread" being defined as the relationship of the primarily longitudinal contour of the bot¬ tom of the insole in the shoe to the shoe supporting surface, i.e. ground, floor, etc. A further and more profound problem occurs when attempting to correctly fit the usually somewhat differing girths of a person's two feet. Here, the correct fit using this old approach can cause one foot to walk at a higher level than the other, which is orthopedically incorrect and even dangerous not only to the feet, but other portions of the anatomy, including knees, hips, spine and even jaw align¬ ment.
The present invention results from the discovery that the girth of a weight-bearing unshod foot varies significantly with different types of foot supporting surfaces, with the greatest girth produced on a perfectly flat firm surface such as a floor, and the least girth experienced when the same foot
is supported by a more conforming surface such as relatively firm but conforming beach sand. This situation holds true for both static and dynamic conditions, with such girth variations found to amount to several consecutive standard width incre¬ ments. The present invention enables one to duplicate the a- bove conditions faithfully within the shoe itself by its de¬ sign and construction, and in so doing, to allow the shoe to afford a comfortable and correct fit over a range of several consecutive standard "widths".
Summary of the Invention
The present invention has as one of its principal ob¬ jects the construction of a girth-adjustable shoe whereby such girth adjustment is brought about by varying the contours of the surface of the insole while precluding any change in the effective functioning height of the foot from the ground.
It is another object of this invention to provide means to effect such contour and girth variations that will comfort¬ ably and correctly fit and support the foot.
It is a further object of the invention to provide for use in such girth-adjustable shoes, systems of girth adjust¬ ment that will be safe and simple to use, economical, and a- daptable to the widest possible range of footwear styles and uses.
The shoe of the present invention comprises a shoe that can be generally conventional in construction except for being manufactured preferably on a specially designed last of a girth or 'width' equal to the widest width a shoe made thereon is expected to accommodate. Such a last has additional materi¬ al on its bottom surface to compensate for the volume of the insole that will later be inserted in the finished shoe to ad¬ just the shoe to the maximum of the shoe's designed girth
range, i.e. a man's EE shoe should be made on an EE last hav¬ ing extra 'depth' added thereto so that the resulting extra- depth shoe made thereon with a maximum girth insole inserted therein will exactly fit a man's EE foot.
In one embodiment, a set of variously contoured insole assemblies comprising a socklining and an insole support mem¬ ber are provided for each shoe size, whereby the degree of contouring of each of said separate insole assemblies effects, when used in said shoe, a like degree of girth adjustment of said shoe. The insole assemblies can vary incrementally ac¬ cording to the preference of the manufacturer, and may be marked for easy identification thereof, preferably in the cus¬ tomary N/M/W or consecutive letter width markings matching the increments.
Another embodiment of this invention uses an insole as¬ sembly which comprises a socklining and a socklining support member in combination with separate shims. The shims, which are disposed underneath the socklining support member, act to contour the outside edges of the socklining support member, with the degree of contour varying relative to the size and/or number of shims used.
A still further embodiment of the invention employs a manually adjustable insole assembly designed for use in those particular cases where relatively frequent girth adjustment may be called for, and where it would be unrealistic to expect the wearer to always have on hand the additional inserts neces¬ sary for such adjustments. Such cases could range from the typically hard to fit women's dress shoes, to work shoes, armed service footwear, and athletic footwear.
In all of the above embodiments, each varies the contour¬ ing from a lowest substantially constant base line or area which extends approximately along the longitudinal centerline of the-insole ".or insoles mentioned therein. Preferably all of
said insoles or insole assemblies will share a common or at least similar cupped heel area, preferably having orthopedical¬ ly beneficial contours, to which the various contours of the forepart and midsection will be blended, with such blending starting just back of the instep and proceeding to the heel breast, i.e. the forward most portion of said heel cup con¬ tours.
For a fuller understanding of the nature and objects of the present invention, reference should be made to the follow¬ ing detailed description taken in connection with the accom¬ panying drawings.
Brief Description of the Drawings
Figure 1 is a side elevational partially cut-away view of a shoe embodying principles of the present invention;
Figure 2 is a plan view of the insole shown in Fig. 1;
Figure 3 is a transverse cross-sectional elevation of the shoe of Fig. 1, taken at ball line 3-3 thereof, and shown with an insole assembly contoured to afford less girth when in¬ serted in the shoe of the invention than do those of the in¬ sole assemblies shown in Fig. 4 and Fig. 5;
Figure 4 is a transverse cross-sectional elevation of the shoe of Fig. 1, taken at ball line 4-4 thereof;
Figure 5 is a cross- sectional view of another alternate insole assembly to the shoe of Fig. 1, also taken at line 5-5;
Figure 6 is a cross-sectional view of the insole assem¬ bly shown in Fig. 1, taken along heel-breast line 6-6 thereof;
Figure 7 is a broken cross-sectional view taken at line
7-7 of Figure 1, of another alternate insole assembly, having removable side edged shims of two typical conformations;
Figure 8 is a side elevational partially sectional view of a shoe of another embodiment of the present invention;
Figures 9, 10, and 11 are cross- sectional elevations of the shoe of Figure 8, taken along lines 9-9, 10-10, and 11-11 respectively, with three typical insoles allowing for three different amounts of girth adjustment;
Figure 12 is a plan view of an alternative single manual¬ ly adjustable insole assembly which could be used in a shoe similar to that of Fig. 1, but one having extra depth therein to accept said assembly's extra depth in those areas;
Figure 13 is a side elevational section of the insole as¬ sembly of Fig. 12;
Figure 14 shows a transverse section of the insole assem¬ bly of Fig. 13 taken along waist line 14-14 of Fig. 12;
Figure 15 shows a transverse section of the insole assem¬ bly of Fig. 13, taken along heel-breast line 15-15 of Fig. 12;
Figure 16 is a transverse section of the insole assembly of Fig. 13, taken along toe line 16-16 of Fig. 12;
Figure 17 shows a lengthwise view of the lengthwise mov¬ able edge ramp shown in Figs. 12 and 13;
Figure 18 shows a transverse section of the edge ramp shown in Fig. 17, taken along instep line 18-18 thereof;
Figure 19 shows a transverse section of the edge ramp shown in Figs. 17, taken along ball line 19-19 thereof;
Figure 20 shows a transverse section of the edge ramp shown in Figs. 17, taken along toe line 20-20 thereof; and
Figure 21 shows a partially exploded perspective view of the single insole assembly of Figure 12.
Detailed Description of the Invention
Referring to the drawings, the adjustable girth shoe con¬ struction of the present invention will be described with ref¬ erence to the well-known handsewn loafer or genuine moccasin, also known in the art as 'tubular' upper construction. It should be understood that this is being done for ease of ref¬ erence, and that this invention is applicable to most other categories and styles of footwear as well. In the various em¬ bodiments described hereinafter, like reference numerals refer to like members which function in the same or similar manner.
Referring to the drawings, Fig. 1 shows a shoe 20 com¬ prising an upper 22 attached to bottom 23. The upper 22 may be made of any suitable material such as leather, vinyl, or the like. Bottom 23, shown as a unitsole, is made of materi¬ als such as rubber, plastic, or the like and is attached to the upper by any suitable means such as stitching, adhesive bonding or the like. Bottom 23 can also be a conventional assembly of bottom elements (not shown) including sole, mid- sole, heel, welt, shank, and the like. Alternatively, bottom 23 can even be part of the upper as is the case in genuine "camp" or Indian sole-less moccasins. Shoe 20 is manufactured on a last of the widest width and largest girth of the width and girth ranges the shoe 20 is designed to accommodate. Shoe 20 also contains an insertable insole assembly 24 comprising a socklining 25 and socklining support member 26 attached to socklining 25, preferably by molding the two members together, although other suitable attachment means, such as adhesive bonding, may be employed. Socklining 25 is made of a suitable
material and as presently preferred is made from CambrelleR synthetic non-woven fabric, available from Faytex Corp. of Braintree, MA. Socklining support member 26 is preferably a polypropylene molded part. In the embodiments shown in Figs. 1-11, a number of different insole assemblies may be inserted into the shoe 20 to achieve different girths. The different insole assemblies have different surface contours in and near the ball, waist, and instep areas of the foot. As shown in Fig. 2, however, each of the insole assemblies of any matched set, such as shown separately in Figs. 2-5, 7, and 9-11, has essentially the same thickness generally along the line 29-29 which extends longitudinally down the center of the insole as¬ sembly. Each insole assembly varies in countour transversely outward from line 29-29 particularly in the critical fitting zone of the ball 31, waist 33, and instep 35, hereinafter re¬ ferred to as the "B I zone." In the embodiment shown in Figs. 12 - 21, the insole assembly also maintains a constant thick¬ ness along its longitudinal center line.
Figs. 3-5 show three different insole assemblies which may be inserted in shoe 20 to achieve different girths. Fig. 3 shows an insole assembly 24 which is of maximum contour in the BWI zone, - and therefore adjusts the inside girth of the shoe in which" it is placed to a relatively narrow girth, typi¬ cally referred to as an 'N' width marking. Fig. 4 shows the insole assembly 24 of Fig. 1 as it would appear in the same ball line section as that of Fig. 3; however, in this embodi¬ ment it occupies less volume in shoe 20 than does insole 24 of Fig. 3, and consequently affords the shoe greater girth, i.e. a medium or M' width. Figure 5 shows an insole assembly which provides the maximum girth available, typically desig¬ nated as a wide or 'W width. In this latter version, the in¬ sole assembly is substantially flat, and of a uniform trans¬ verse thickness, substantially the same as that of the central portions of the insole assemblies of Figs. 3 and 4.
Fig. 6 shows a preferably, but not necessarily, common
heel contour that could be shared by all of the insole assem¬ blies of Figs. 1-5, and comprises socklining 25 bonded to sock¬ lining support element 26. Such a heel contour may also be possessed by the shoe of Figs. 8-11, hereinafter described.
Fig. 7 shows another embodiment with slightly different insole assemblies than those described in Figs. 3-5. In this embodiment, a single insole assembly 24 comprising socklining element 25 and a socklining support member 26 having side edge openings or slots therebetween to receive shims 28, which can be of any number and thickness, including at least one shim that can be used on each side, and connected preferably at the toe and/or heel. Such shims provide effective insole assembly contours similar to those shown in Figs. 3-5, and limited in degree to the extremes shown in Fig. 3 and Fig. 5. The shims 28 could be held in place by temporary contact cement, pres¬ sure sensitive tape, VelcroR , or similar means, including merely by friction and by the tendency of the upper 22 to hold them in position. In any case, the use of such shims would preferably be limited to those effecting the same type of con¬ touring as that in Figs. 3-5.
Another embodiment of the invention is shown in Figs. 8 - 11. In this embodiment, another set of insole assemblies is shown, similar to those of Figs. 3-5, except that the central portion of each is thicker than that of the insole assemblies of Figures 3-5, to allow an additional type of side edge con¬ touring to facilitate a greater overall degree of girth adjust¬ ment than that possible with the insole assemblies of Fig. 3-5. Fig. 8 shows the shoe 30 in a side- elevational partially cut-away sectional view, with upper 32, attached by stitching 34 to midsole 36, which is attached to unitsole 38 preferrably by an adhesive. Insole assembly 40, shown in shoe 30 comprises a socklining 42, and socklining support 44, made from the same materials as those described in Figs. 1-6, and having longitu¬ dinally central portions of a substantially greater common thickness than those of Figs. 1-6. Fig. 9 is a cross-section
taken along ball line 9-9 of Fig. 8, showing an insole assem¬ bly 40 that when placed in shoe 30 takes up enough of the in¬ side volume of shoe 30 to comfortably but effectively limit the girth of the shoe 30 to the least girth of its designed girth range. Fig. 10 shows another insole assembly 40, again of the same center thickness as that of Fig. 9 to keep the foot height and tread constant, but having a flatter contour along its top surface, to allow shoe 30 with assembly 40 there¬ in to fit a fuller girthed 'M' width foot than the 'N' width accomodated in Fig. 9. Fig. 11 shows still another assembly 48, which is similar to assembly 40, except that edge bevels 50 on the lower side edges of assembly 48 allow another degree of upward motion of upper 32, without necessitating any de¬ formation of sole 38. This extra amount of upward motion of upper 32, together with the flat contour of the top surface of 48 cooperate to, allow shoe 30 to have the maximum girth of its designed girth range when assembly 48 is inserted in place therein. Again, as in Figs. 1-7, the number of inserts and their incremental dimensional differences are optional, as is the use of shims as described in Fig. 7.
Another embodiment of the invention, preferred in situa¬ tions where immediate adjustment is required, and where the constant availability of the necessary sets of inserts could pose a problem, is shown in Figs. 12-21. In this embodiment, the effective contours of the forward weight-bearing portions of the top of the midsole in the BWI zone can be infinitely varied between fixed limits, with the preferred contours selected by manual adjustment. The insole assembly 50 is shown in plan view in Fig. 12, and in side section in Fig. 13, and comprises a socklining 52, preferably made of CambrelleΛ fabric attached to an innersole 54, preferably made of polypropylene. Under the innersole 54 are longitudinally slidable adjustable edge ramps 56 and 58, preferably molded of relatively firm but flexible plastic material such as cellular ethylene vinyl acetate or the like. The ramps rest on insole assembly base 60, which is preferably molded of polypropyl-
ene. The base 60 contains a drum 62 which may be rotated us¬ ing a screwdriver, coin, or the like inserted in the slotted head 64 of drum 62. As best shown in * Fig. 12, cables 66 are attached to and wrapped around drum 62 and are attached to ramps 56, 58 by cable fastenings 68, 70. The cables pass a- round and/or through grommet 72 and along base 60, under or near the position of fastenings 68, 70. The cable geometry is designed to move both ramps in the same direction. It will be seen that rotation of the drum 62 in a counter-clockwise direc¬ tion will produce a like amount of cable motion as shown by the arrows on cables 66 to move ramps 56 and 58 rearwardly to¬ wards, and eventually to, heel-breast line 15-15. As said ramps move longitudinally, they are preferably contained by and move in tunnels 82 which are formed of a preferably slight¬ ly stretchable thin but durable plastic treated so as to be heat sealable or alternately stitchably attached to base 60 at substantially the center 74 of the bottom of same, as best shown in Fig. 15, and at the peripheral edges to innersole 54 and thereby to socklining at heatseal 52. As the ramps 56, 58 move rearwardly they are supported by opposing ramps 76, 78 shown in Fig. 15 at their maximum angle at their rearward end at the heel-breast line 15- 15 in Fig. 12. Forward of that lo¬ cation, as shown in Fig. 14, the ramps 56 and 58 gradually flatten to a horizontal condition at ball line 14-14. The use of such opposing fixed ramps 76, 78 facing the movable ramps 56, 58 allows for the simultaneous and identical contour change of the top surfaces of the side edge areas of the in¬ sole assembly throughout the BWI zone, which is necessary for optimum and correct girth adjustment in this girth -critical fitting area.
Fig. 17 shows a lengthwise view of the ramps 56, 58 including cable fastening 80 in same. Figs. 18-20 show cross- sections of ramp 58 taken at lines 18-18, 19-19, and 20-20 re¬ spectively. Ramp 56 is essentially the mirror image of ramp 58. It is worth noting that while this assembly as shown ap¬ pears not to support the side edges of the foot in the shank
area, i.e. between the lines 3-3 and 6-6 of Fig. 1, actually, and especially in shoes having raised heel areas, this area is relatively non-weight- bearing and these edge voids consequent¬ ly cannot be felt by a foot thereon.
Fig. 21 shows the insole assembly of Figs. 12-20 in a partially exploded view, eliminating the tunnel wall materials to make this embodiment easier to understand.