Sewing machine and method of controlling operation of the same

Abstract

A sewing machine is provided, which includes a table, support posts, upper and lower frames, a head unit, a bed unit, an X-axial head-unit-transport means and an X-axial bed-unit-transport means. An object is placed on the table. The support posts are provided on opposite sides of the table. The upper and lower frames connect the support posts to each other. The head unit is provided on the upper frame so as to be movable in an X-axis direction. The head unit has a head-unit-rotating means for rotating a sewing head. The bed unit is provided on the lower frame so as to be movable in the X-axis direction. The bed unit has a bed-unit-rotating means for rotating a sewing bed. The X-axial head-unit-transport means moves the head unit on the upper frame horizontally. The X-axial bed-unit-transport means moves the bed unit on the upper frame horizontally.

1 . A sewing machine comprising:
 a table, on an upper surface of which an object to be sewn is placed;   support posts provided on opposite sides of the table;   upper and lower frames connecting the support posts to each other;   a head unit provided on the upper frame so as to be movable in an X-axis direction, the head unit having head-unit-rotating means for rotating a sewing head within a predetermined range;   a bed unit provided on the lower frame so as to be movable in the X-axis direction, the bed unit having bed-unit-rotating means for rotating a sewing bed within a predetermined range;   X-axial head-unit-transport means for moving the head unit on the upper frame in a horizontal direction; and   X-axial bed-unit-transport means for moving the bed unit on the upper frame in the horizontal direction.   
     
     
         2 . The sewing machine as set forth in  claim 1 , wherein the X-axial head-unit-transport means comprises:
 an X-axial head-unit-transport motor providing a drive force;   a transport screw connected to a drive shaft of the X-axial head-unit-transport motor by power transmission means;   a head unit transport bracket reciprocating in the horizontal direction depending on rotation of the transport screw, with the head unit mounted to a front surface of the head unit transport bracket; and   a guide rail coupled to guide couplers of the head unit transport bracket so that the head unit transport bracket is able to move horizontally on the upper frame.   
     
     
         3 . The sewing machine as set forth in  claim 2 , wherein the head unit is mounted to the front surface of the head unit transport bracket; a transport box is provided on a central portion of a rear surface of the head unit transport bracket, the transport box being provided around the transport screw; and the guide couplers are provided on upper and lower ends of the head unit transport bracket, the guide couplers being coupled to the guide rail. 
     
     
         4 . The sewing machine as set forth in  claim 2 , wherein the drive shaft of the X-axial head-unit-transport motor is connected to the transport screw by a coupling. 
     
     
         5 . The sewing machine as set forth in  claim 1 , wherein a drive source of the X-axial head-unit-transport means comprises a rotating motor. 
     
     
         6 . The sewing machine as set forth in  claim 1 , wherein a drive source of the X-axial head-unit-transport means comprises a linear motor. 
     
     
         7 . The sewing machine as set forth in  claim 1 , wherein the X-axial bed-unit-transport means comprises:
 an X-axial bed-unit-transport motor providing a drive force;   a transport screw connected to a drive shaft of the X-axial bed-unit-transport motor by power transmission means;   a bed unit transport bracket reciprocating in the horizontal direction depending on rotation of the transport screw, with the bed unit mounted to a front surface of the bed unit transport bracket; and   a guide rail coupled to guide couplers of the bed unit transport bracket so that the bed unit transport bracket is able to move on the lower frame.   
     
     
         8 . The sewing machine as set forth in  claim 7 , wherein the bed unit is mounted to the front surface of the bed unit transport bracket; a transport box is provided on a central portion of a rear surface of the bed unit transport bracket, the transport box being provided around the transport screw; and the guide couplers are provided on upper and lower ends of the bed unit transport bracket, the guide couplers being coupled to the guide rail. 
     
     
         9 . The sewing machine as set forth in  claim 7 , wherein the drive shaft of the X-axial bed-unit-transport motor is connected to the transport screw by a coupling. 
     
     
         10 . The sewing machine as set forth in  claim 1 , wherein a drive source of the X-axial bed-unit-transport means comprises a rotating motor. 
     
     
         11 . The sewing machine as set forth in  claim 1 , wherein a drive source of the X-axial bed-unit-transport means comprises a linear motor. 
     
     
         12 . The sewing machine as set forth in  claim 1 , wherein the head-unit-rotating means comprises:
 a head unit rotating motor used as a power source;   a power transmission unit connected to a drive shaft of a rotating motor, the power transmission unit transmitting a drive force of the rotating motor;   a driven shaft rotated by the drive force of the rotating motor transmitted by the power transmission unit; and   the sewing head provided on the driven shaft, the sewing head being rotated around the driven shaft.   
     
     
         13 . The sewing machine as set forth in  claim 12 , wherein the power transmission unit comprises a rotating drive gear reducing an rpm of the rotating motor and transmitting the drive force to the driven shaft at a reduced rpm. 
     
     
         14 . The sewing machine as set forth in  claim 13 , wherein the rotating drive gear comprises a bevel gear configured such that the drive shaft is at a right angle to the driven shaft. 
     
     
         15 . The sewing machine as set forth in  claim 12 , wherein the power transmission unit comprises a timing belt. 
     
     
         16 . The sewing machine as set forth in  claim 1 , wherein the bed-unit-rotating means comprises:
 a bed unit rotating motor used as a power source;   a power transmission unit connected to a drive shaft of a rotating motor, the power transmission unit transmitting a drive force of the rotating motor;   a driven shaft rotated by the drive force of the rotating motor transmitted by the power transmission unit; and   the sewing bed provided on the driven shaft.   
     
     
         17 . The sewing machine as set forth in  claim 16 , wherein the power transmission unit comprises a rotating drive gear reducing an rpm of the rotating motor and transmitting the drive force to the driven shaft at a reduced rpm. 
     
     
         18 . The sewing machine as set forth in  claim 17 , wherein the rotating drive gear comprises a bevel gear configured such that the drive shaft is at a right angle to the driven shaft. 
     
     
         19 . The sewing machine as set forth in  claim 16 , wherein the power transmission unit comprises a timing belt. 
     
     
         20 . The sewing machine as set forth in  claim 1 , wherein a momentum of a rotating motor of the bed-unit-rotating means is synchronized with a rotating motor of the head-unit-rotating means so that the rotating motors are operated together. 
     
     
         21 . The sewing machine as set forth in  claim 1 , further comprising:
 head-unit-lift means provided between the X-axial head-unit-transport means and the head unit, the head-unit-lift means moving the sewing head upwards and downwards between a stand-by position and a work position.   
     
     
         22 . The sewing machine as set forth in  claim 21 , wherein the head-unit-lift means comprises:
 a lift actuator installed in a main body of the sewing machine by an actuator support bracket, the lift actuator providing a drive force to move the sewing head upwards or downwards; and   a lift plate coupled at a central portion of a front surface thereof to the sewing head, the lift plate being coupled on an upper end of a rear surface thereof to a head unit connection bracket connected to a drive part of the lift actuator, with guide means mounted to opposite sides of the rear surface of the lift plate.   
     
     
         23 . The sewing machine as set forth in  claim 21 , wherein the head-unit-lift means further comprises:
 a support plate coupled on opposite sides of a front surface thereof to the guide means, with an actuator support bracket mounted to a central portion of a rear surface of the support plate, the actuator support bracket supporting the lift actuator thereon.   
     
     
         24 . The sewing machine as set forth in  claim 1 , wherein the X-axial head-unit-transport means and the X-axial bed-unit-transport means comprises:
 an integrated X-axial transport motor provided on at least one of the support posts;   an upper transport unit provided on the upper frame, the upper transport unit being connected to the head unit;   a lower transport unit provided on the lower frame, the lower transport unit being connected to the bed unit;   upper guide means provided on the upper frame so that the head unit is transported along the upper frame by the upper guide means;   lower guide means provided on the lower frame so that the bed unit is transported along the lower frame by the lower guide means; and   power transmission means for transmitting a rotating force of the integrated X-axial transport motor to the upper transport unit and the lower transport unit at a same time.   
     
     
         25 . The sewing machine as set forth in  claim 24 , wherein the power transmission means comprises:
 a drive pulley provided on an output shaft of the integrated X-axial transport motor;   an upper driven pulley provided on an end of the upper transport unit;   a lower driven pulley provided on an end of the lower transport unit; and   a timing belt coupled to the drive pulley, the upper driven pulley and the lower driven pulley together so that the upper transport unit and the lower transport unit are operated at a same time by a drive force of the drive pulley.   
     
     
         26 . The sewing machine as set forth in  claim 25 , further comprising:
 a tensioner pulley for applying a tensile force to the timing belt.   
     
     
         27 . The sewing machine as set forth in  claim 24 , wherein each of the upper transport unit and the lower transport unit comprises a ball screw. 
     
     
         28 . The sewing machine as set forth in  claim 24 , wherein each of the upper transport unit and the lower transport unit comprises a wire. 
     
     
         29 . The sewing machine as set forth in  claim 24 , wherein each of the upper guide means and the lower guide means comprises a guide rail. 
     
     
         30 . The sewing machine as set forth in  claim 24 , wherein each of the upper guide means and the lower guide means comprises an LM guide. 
     
     
         31 . The sewing machine as set forth in  claim 1 , further comprising:
 Y-axial transport means for transporting a sewing frame supporting the object thereon in a Y-axis direction.   
     
     
         32 . The sewing machine as set forth in  claim 31 , wherein the Y-axial transport means comprises:
 a Y-axial frame extending a predetermined length in the Y-axis direction;   a Y-axial linear motor provided on the Y-axial frame, the Y-axial linear motor providing a drive force to move the sewing frame in the Y-axis direction; and   a support unit provided such that the sewing frame is transported in the Y-axis direction by operation of the Y-axial linear motor.   
     
     
         33 . The sewing machine as set forth in  claim 1 ,
 wherein the head unit comprises a plurality of head units arranged in a row on a front surface of the upper frame,   the bed unit comprises a plurality of bed units arranged in such a way as to correspond to the respective head units, and   a plurality of objects are held by a single sewing frame on the table so that a plurality of sewing operations are able to be conducted simultaneously.   
     
     
         34 . The sewing machine as set forth in  claim 1 , wherein a sewing frame holding the object comprises a plurality of sewing work areas, and objects are supported on the respective sewing work areas. 
     
     
         35 . The sewing machine as set forth in  claim 34 , wherein the sewing frame comprises a plurality of subsidiary sewing frames provided on the single sewing frame so as to be individually removable therefrom. 
     
     
         36 . The sewing machine as set forth in  claim 34 , wherein an indication is provided on the sewing frame, the indication containing information instructing about a working method, and a reader for scanning the indication is provided on the head unit,
 wherein the reader reads the information contained in the indication and transmits the information to a control unit.   
     
     
         37 . The sewing machine as set forth in  claim 36 , wherein the indication comprises a barcode, and the reader comprises a barcode reader. 
     
     
         38 . A method of controlling operation of a sewing machine comprising a head unit and a bed unit that are allowed to be transported in an X-axis direction and rotated around a Z-axis while sewing, the method comprising:
 (a) positioning a sewing needle of the head unit above a needle plate;   (b) operating an X-axial transport motor, a Y-axial transport motor, a head unit rotating motor and a bed unit rotating motor in response to information input to a control unit; and   (c) moving the sewing needle downwards by operation of an upper shaft drive motor and a lower shaft drive motor to form a stitch, and returning to (b) operating when the sewing needle is moved upwards and positioned above the needle plate, and repeating (b) operating and (c) moving.   
     
     
         39 . The method as set forth in  claim 38 , wherein an rpm of the upper shaft drive motor and an rpm of the lower shaft drive motor are increased or reduced in proportion to rpms of the X-axial transport motor, the Y-axial transport motor, the head unit rotating motor and the bed unit rotating motor. 
     
     
         40 . The method as set forth in  claim 38 , wherein after the rpm of the upper shaft drive motor and the rpm of the lower shaft drive motor are reduced, the head unit rotating motor and the bed unit rotating motor are operated. 
     
     
         41 . The method as set forth in  claim 38 , wherein the rotating speed of the upper shaft drive motor and the rotating speed of the lower shaft drive motor are controlled in response to an angle at which the head unit and the bed unit rotate.