Sole for a shoe
United States Patent [1 1 Frau Tomas 1 1 SOLE FOR A SHOE [75] Inventor: Juan Frau Tomas, Palma De Mallorca, Spain {731 Assignee: Jaun Frau S. A., Palma De Mallorca, Spain 3.698.108 10/1972 Brunner 36/115 Primary E.\ami:wr-Patrick D. Lawson Attorney, Agent, or Firm-Wenderoth, Lind &amp; Ponack [451 Apr. 8, 1975 [57} ABSTRACT An improved sole for a shoe made from a single piece. purposely sized to receive thereon the entire foot of the user. and of the type whose inner shank is anatomically raised at the ball portion to act as a support for the arch of the foot. includes a heel supporting zone in a lower plane than the ball supporting zone which. on the other hand. is slightly raised at its center in a rounded fashion. The sole includes means to prevent the foot from twisting outwards, when resting. and means whereby the weight of the user rests on the big toe. at the end of each stride, which means are respectively comprised of a longitudinal recess in the upper surface of the shank situated between the raised support of the arch and the outer opposite edge, and of a decrease in the thickness of the fore portion of the sole which starts approximately midway of the hall and progresses towards the toe portion. forming a curved surface. whose front view defines an oblique front, when such decrease reaches its maximum value coinciding with the supporting zone for the big toe.  
 1 Claim, 12 Drawing Figures SOLE FOR A SHOE OBJECTS OF THE INVENTION The present invention refers to a sole for shoes with which two essential objects are fundamentally sought:  
  1. A rational support for the foot when the user is at rest; and  
  2. A correct displacement of weights, benefitting from and using the functional structure of the foot, during walking of the user.  
  As will subsequently be seen, the first mentioned object is mainly achieved with the contemplated configuration of the upper portion of the sole, which retains the exact anatomical characteristics of the user, and the second object is achieved due to the specially rounded shape of the lower foresurface of the ball.  
  Other secondary objects of the invention are constituted by the light-weight construction of the sole, readily and economically obtained, which can adequately be used with any type of shoe.  
 SUMMARY OF THE INVENTION As will subsequently be explained in detail with reference to the set of drawings attached hereto, the sole is of the type made from a single piece, purposely sized to receive thereon the entire foot of the user. The inner shank is anatomically raised at the ball portion so as to act as a support for the arch of the foot.  
  The main characteristics of the sole, with regards to obtaining a rational support for the foot when the user is at rest, reside in the fact that the heel supporting zone is in a lower plane than the ball supporting zone which, is slightly raised at its center, in a rounded manner, and that means have been provided to prevent the foot from twisting outwards. It will later be seen that such means comprise a longitudinal recess in the upper surface of the shank situated between the raised support of the arch of the foot and the outer opposite edge.  
  With respect to the achievement of the second main object of the invention, which consists in obtaining a correct displacement of weights during walking of the user, the invention contemplates a decrease in the thickness of the foreportion of the sole, which starts approximately midway of the ball and progresses towards the toe portion, forming a curved surface which, as will be seen, is fundamentally cylindrical. It will also be seen that such decrease, provided that the zone of the toe portion which corresponds to the support for the big toe is in a more forward position, establishes an oblique front, reaching its maximum value precisely in coincidence with the mentioned supporting zone for the big toe of the user.  
 BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in more detail below, taken with the accompanying drawings, wherein:  
  FIG. I is a side elevational view, taken from the inner side, of a sole for shoes made in accordance with the invention.  
  FIG. 2 is an upper plan view of the same sole for shoes, wherein the lines which approximately define the superficial changes which give rise to the previously mentioned anatomical conformation, are shown.  
  FIG. 3 is a lower plan view of the same sole, wherein the line from which the curvilineal decrease of the foreportion of the ball departs is shown.  
  FIG. 4 is a second side elevational view of the sole, taken from the outer side thereof.  
 FIG. 5 is a front elevational view of the sole.  
 FIG. 6 is a rear elevational view of the sole.  
  FIG. 7 is a cross-sectional view of the sole, taken on plane A-B of FIG. 2.  
  FIG. 8 is a cross sectional view of the sole, taken on plane CD of FIG. 2.  
  FIG. 9 is a cross sectional view of the sole, taken on plane E-F of FIG. 2.  
  FIG. 10 is another cross sectional view of the sole, taken on plane G-H of FIG. 2.  
  FIG. 11 is a perspective view of the sole, taken from the lower part thereof.  
  Finally, FIG. 12 illustrates a perspective view of the sole, taken from the upper part thereof.  
 DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings and more particularly to FIGS. 1 to 4, II and 12, it can be seen, as has already been stated, that the sole is of the type which is made from a single piece. The shank portion adjacent to the inner edge of the sole is raised at the upper portion so as to give rise to the formation of anatomically shaped supporting means 5 for the arch of the foot of the user.  
  With this general construction a sole can be formed of plastic materials, with low production costs and of a light weight, which weight can be even more reduced by forming hollows in the sole, such as those illustrated in FIGS. 2 and 12.  
  FIGS. 2 and 7 mainly illustrate the anatomical construction of the upper part of the sole, in order to obtain a rational support of the weight of the user and to prevent outward twisting of the foot of the user, as a result of the existence of the raised zone 5 of the inner shank.  
  FIG. 2 particularly illustrates the lines which define the changes in the plane of the upper zone of the sole, giving rise to the anatomical support to be obtained. These lines, beginning with that marked 11 which indicates the end of the raised zone 5 of the inner shank, extend in the direction of the ball (line 12), they surround the toe portion (line 13), they border the outer edge of the sole (line 14) and continue along the shank (line 9) until they reach the heel which they enclose (line 10), and then they are slightly deflected towards the edge of the inner zone of the sole.  
  The assembly oflines 9, 10, I1, 12, I3 and I4 define a slight change in height between the central zone of the sole, encircled by these lines, and the peripheral zone of the mentioned sole, which is in a higher plane. Thus, for example, a longitudinal channel 4 is formed in the zone of the outer shank, exactly opposite to the raised shank 5. Such channel is limited, at the outer portion, by the highest border which continues along the side, whereby stopping means are achieved which prevent the foot from twisting outwards, due to the presence of the already mentioned elevation 5. This type of channel or recess can perfectly be seen in FIGS. 8 and 9 which, as already mentioned, correspond to cross sectional views of the sole, taken on planes CD and E-F of FIG. 2, respectively.  
  In the heel portion 1, line 10 forms a dip or depression by means of which such portion remains in a lower plane than that occupied by the ball 2, as can more clearly be seen in FIGS. I and 4. Furthermore, as a result of the deflection of line 10 towards the inner edge of the sole, the depression of heel 1 forms, within the same zone, a portion 8 which is situated at an even lower level (see FIGS. 2 and 10) and which helps channel 4 so that the foot is correctly placed on the raised shank 5, without the possibility of twisting outwards.  
  Furthermore, and as can clearly be seen in FIGS. 2 and 7, the central cut-down portion in the central zone of the ball which is situated between the deflection lines I2, 13 and 14, has a small rounded promontory 3 which is designed so as to be accomodated to the ball of the user, exactly behind the initial articulations of the toes, in order to achieve a perfect support.  
  On the other hand, FIGS. 1, 3, 4, 5 and II should be pointed out with regards to the characteristics of the foot in order to achieve a correct displacement of weights during walking of the user. These figures illustrate that the lower part of the foreportion of the sole has a decrease in the thickness which starts approximately midway of the ball, from an imaginary transversal line 7, and progresses towards the toe portion, forming a substantially cylindrical curved surface 6 which, as can be seen in FIG. 5, forms an oblique front, according to which the thinnest part is precisely that which corresponds to the supporting zone for the big toe of the user.  
  As is clear, the fact that the cylindrical surface 6 precisely forms an oblique front, as illustrated in FIG. 5, is subject to the fact that the zone of the sole for shoes corresponding to the support for the big toe is placed forwards, as illustrated in FIG. 2. n the other hand, if the toe portion of the sole for shoes were regularly rounded, the front to which the curved surface 6 should give rise would be perfectly regular.  
  Nevertheless, it should be emphasized that the shape of the sole illustrated in FIG. 2 corresponds to a preferred embodiment of the invention, since it is advantageous for the oblique front, represented in FIG. 5, and consequently a maximum decrease in the thickness of the sole, coinciding with the supporting zone for the big toe, to be produced. In this way, not only can a stride be made more easily wearing shoes provided with this sole, due to the rounded zone 6, but the weight of the user rests precisely on the big toe, which is the most powerful and which, consequently, is in a better position to advantageously withstand the operation.  
 I claim:  
  I. An improved shoe sole made from a single piece of a size to receive thereon the entire foot of the user, said sole having:  
 the inner shank thereof anatomically raised at the ball portion to provide a support for the arch of the foot;  
 a ball supporting zone slightly raised at its center in a rounded fashion;  
 a heel supporting zone in a lower plane than said ball supporting zone;  
 means for preventing a foot from twisting outwardly when resting, said twist preventing means comprising a longitudinal recess in the upper surface of the shank at a position between the raised support for the arch and the outer opposite edge; and  
 means for causing the weight of the user to rest on the big toe thereof at the end of each stride, said means for causing comprising a fore portion of the sole having a decrease in thickness beginning approximately midway of the ball supporting portion and progressing toward the toe portion, said decrease forming a curved surface, the front view of which defines an oblique front, said decrease being at a maximum at the supporting zone for the big lOC.  
 asses