Ultrasonic lapping apparatus for drawing dies

In ultrasonic lapping apparatus for finishing or reconditioning holes in drawing dies, the combination of:

• a. an ultrasonic generator;
• b. a transducer adapted to be excited by said ultrasonic generator to produce mechanical oscillations;
• c. a lapping needle adapted to receive the mechanical oscillations from said transducer;
• d. a turntable for supporting a die thereon, said turntable being arranged opposite to a tip of said lapping needle and being normally axially aligned therewith;
• e. drive means for rotating said turntable about its central axis relative to said lapping needle;
• f. rolling means for causing said turntable to roll about an axis passing through the die mounted thereon, said rolling means comprising:
• 1. a swing arm pivotally supported at one end for swinging motion about the axis passing through the die on said turntable, said swing arm carrying said turntable;
• and
• 2. means arranged adjacent another end of said swing arm for causing the swinging motion of same;
• g. said means for causing the swinging of said swing arm comprises:
• 1. a rotary disc;
• 2. means for imparting rotation to said disc relative to said swing arm;
• 3. a cam mounted on said disc;
• and
• 4. spring means yieldably urging said other end of said swing arm into contact with said cam;
• h. means for adjustably moving said turntable in either of two right-angular directions in a plane at right angles with said lapping needle for fine adjustment of the position of said turntable with respect to said lapping needle;
• i. said adjustable moving means comprises:
• 1. a supporting frame substantially integrally including a portion to which said swing arm is pivotally connected at said one end thereof;
• 2. first spring support means supporting said supporting frame, said first spring support means being resiliently yieldable to permit movement of said supporting frame in one of said two right-angular directions relative to said lapping needle;
• 3. first manually actuable means for adjustably moving said supporting frame in said one direction against the force of said first spring support means;
• 4. second spring support means through which said turntable is mounted on said swing arm, said second spring support means being resiliently yieldable to permit movement of said turntable in the other of said two right-angular directions relative to said swing arm;
• and
• 5. second manually actuable means for adjustably moving said turntable in said other direction against the force of said second spring support means;
• j. said first and second support means each comprise a pair of leaf springs;
• k. said turntable being coaxially provided with a shaft rotatable simultaneously therewith;
• l. a bearing for rotatably supporting said shaft of said turntable;
• m. said bearing having means for yieldably urging the die on said turntable against said lapping needle under adjustable pressure;
• and
• n. said bearing including:
• 1. an outer sleeve, said turntable being carried by said swing arm via said outer sleeve;
• 2. an inner sleeve rotatably nested in said outer sleeve and formed substantially integral with said second pulley in coaxial relationship for simultaneous rotation therewith relative to said outer sleeve, said shaft of said turntable being inserted into said inner sleeve via said second pulley so as to be slidable axially relative to same;
• 3. spring means within said inner sleeve yieldably urging the die on said turntable against said lapping needle via said shaft of said turntable;
• and
• 4. means for adjustably varying the force of said spring means exerted on said shaft of said turntable.