parts shown in the prior art of fig1 - 3 , incl ., are indicated by reference numerals excluding primes . those parts in the first embodiment of fig4 - 7 and 11 , whose parts are equivalent or similar to those of the prior art will be designated by the same reference numerals primed . those parts in the second embodiment of fig8 - 10 , incl ., whose parts are equivalent or similar to those of the prior art will be designated by the same reference numerals double - primed . in fig4 and 11 the shoe tap for dancing of the present invention is generally designated with the reference no . 10 &# 39 ; utilizing a raised hemispherical protrusion 28 in the first member 12 &# 39 ; which coacts with a concave hemispherical surface 28a in the second member 20 &# 39 ; to form a pivot point . in . fig5 the first member 12 &# 39 ; is generally curved , having two raised side portions 14 &# 39 ; and an open portion 32 &# 39 ; whose boundary is defined by the raised side portions 14 &# 39 ; and the first central portion 18 &# 39 ;. in fig6 second member 20 &# 39 ; contains a raised back portion 34 &# 39 ; which extends across its entire width . in operation , second member 20 &# 39 ; can pivot about the raised hemispherical protrusion 28 much more freely in all directions . in fig1 after pivot pin 26 &# 39 ; is placed through first member 12 &# 39 ; and second member 20 &# 39 ; the ends 26a are pressed so that they occupy both first and second recesses 16a and 22a &# 39 ; respectively without binding but causing mutual contact of spherical surfaces 28 and 28a with a slight play . second member 20 &# 39 ; lies in between the two raised side portions 14 &# 39 ; of first member 12 &# 39 ;. second member 20 &# 39 ; with its concave spherical surface 28a can pivot about the raised hemispherical protrusion 28 much more freely in all directions limited only by the restraints imposed by the raised side portions 14 &# 39 ;, pin 26 &# 39 ; and pin heads 26a . in fig8 - 10 , incl ., there is shown an alternate embodiment of the present invention . pivot pin 26 as shown in fig8 is in the form of a screw . this would provide an additional mounting point for attachment of the tap to the shoe . in fig9 the first member 12 &# 34 ; is generally flat and contains no open portion . it has a first central portion 18 &# 34 ;. in the middle of the first central portion 18 &# 34 ; is a raised hemispherical protrusion 28 having at its center a through - bore 16 &# 34 ;. on the bottom of the first member 12 &# 34 ; there is a first recess 16a where through - bore 16 &# 39 ; commences . the entire assembly is preferably made of cast metal . in fig1 the second member 20 &# 34 ; is shown as generally flat and has a second central portion 24 &# 34 ;. in the middle of the second central portion 24 &# 34 ; there is a second through - bore 22 &# 34 ;. on the top of the second member 20 &# 34 ; there is a second recess 22a &# 34 ; where through - bore 22 &# 34 ; commences . the relative positioning of the first member 12 &# 34 ; and the second member 20 &# 34 ; after being secured to each other by pivot pin 26 is shown in fig8 . second member 20 &# 34 ; is placed on first member 12 &# 34 ; so that through - bore 16 &# 34 ; and 22 &# 34 ; are aligned to receive pivot pin 26 &# 34 ;, which through - bores are preferably of equal diameters . pivot pin 26 &# 34 ; is of the general cylindrical shape having a diameter smaller than that of through - bores 16 &# 34 ; and 22 &# 34 ;. an improved tapping sound is achieved due to the increased surface area that may be contacted by second member 20 &# 34 ; on first member 12 &# 34 ; during use of the tap . the shoe tap for tap dancing is secured to the shoe bottom by nails or screws placed through mounting bores 30 &# 39 ; ( 30 &# 34 ;) in the first member 12 ( 12 &# 34 ;). when the user places his or her foot on the floor and proceeds to dance , second member 20 &# 34 ; ( 20 &# 34 ;) may slightly pivot about the raised hemispherical protrusion 28 freely in all directions limited only by the aforementioned constraints . the tapping effect is greatly increased by the use of the raised hemispherical protrusion 28 for a pivot point because as second member 20 &# 39 ; ( 20 &# 34 ;) moves against the raised side portions 14 &# 39 ; ( 14 &# 34 ;) of the first member 12 &# 39 ; ( 12 &# 34 ;), a tap may be created and as second member 20 &# 39 ; ( 20 &# 34 ;) moves against the central portion 18 &# 39 ; ( 18 &# 34 ;) of the first member 12 &# 39 ; ( 12 &# 34 ;) an additional tap may be created . although the invention is described and illustrated with reference to a plurality of embodiments thereof , it is to be expressly understood that it is in no way limited to the disclosure of such preferred embodiments but is capable of numerous modifications within the scope of the appended claims .
a shoe tap for tap dancing having first and second members pivotally connected by a pivot pin . the first member having a raised hemispherical protrusion with a first through - bore . the second member having a mating concave hemispherical recess coaxially disposed relative to a second through - bore . the pivot pin being of a diameter less than the first and second through - bore and extending therethrough and thereby not inhibiting the relative motion of the pivotally mounted second member to the first member affixed to the dancer &# 39 ; s shoe .