Apparatus for Lifting Presser Foot of Embroidery Machine

Abstract

An apparatus for lifting the presser foot of an embroidery machine includes an arm having an upper shaft providing a driving force, a presser foot driving cam mounted on the upper shaft, a transmission member coupled to the presser foot driving cam and making an oscillating motion, a presser foot driving lever connected to the transmission member and pivoting around a predetermined pivoting point thereof in a vertical direction, a presser foot driving block reciprocating along a needle bar guide shaft according to an amount that the presser foot driving lever is pivoted and moving the presser foot in a vertical direction, and a presser foot height adjustor, displacing the pivoting point of the presser foot driving lever to adjust a height of the presser foot.

1 . An apparatus for lifting the presser foot of an embroidery machine, the apparatus comprising:
 an arm having an upper shaft providing a driving force;   a presser foot driving cam mounted on the upper shaft;   a transmission member coupled to the presser foot driving cam and making an oscillating motion;   a presser foot driving lever connected to the transmission member and pivoting around a predetermined pivoting point thereof in a vertical direction;   a presser foot driving block reciprocating along a needle bar guide shaft according to an amount that the presser foot driving lever is pivoted and moving the presser foot in a vertical direction; and   a presser foot height adjustor displacing the pivoting point of the presser foot driving lever to adjust a height of the presser foot.   
   
   
       2 . The apparatus as set forth in  claim 1 , wherein the presser foot height adjustor includes a driving motor that generates driving force, a driving pulley rotatably coupled to the driving motor, a driven pulley pivotably coupled to the driving pulley, an eccentric member installed on the driven pulley, and a presser foot driving lever hinged to the eccentric member at a pivoting point thereof. 
   
   
       3 . The apparatus as set forth in  claim 2 , further comprising a cylindrical supporting means for an eccentric member, which is connected to the driven pulley and has a hole through which the eccentric member passes. 
   
   
       4 . The apparatus as set forth in  claim 3 , wherein the eccentric member includes large and small spindles on opposite sides of a circular body thereof, the small spindle being connected in a hinge hole of the presser foot driving lever, and the large spindle passing through the supporting means to be connected to the driven pulley. 
   
   
       5 . The apparatus as set forth in  claim 2 , wherein the presser foot height adjustor adjusts a height of a bottom dead point of the presser foot according to a thickness of a sewing material. 
   
   
       6 . The apparatus as set forth in  claim 1  or  5 , wherein the presser foot height adjustor adjusts the height of the bottom dead point of the presser foot to a programmed height according to the thickness of the sewing material.