Patent ID: 7614354
Filing Date: 2009-11-10
Classification: D05B,D05C

Abstract:
1. A bobbin changer apparatus for changing a lower thread bobbin mounted in a rotary hook of a sewing machine by acquiring a bobbin case, containing a lower thread bobbin, from a bobbin stock section provided apart from the rotary hook, said bobbin changer apparatus comprising: a bobbin grasping device for grasping a bobbin case at a distal end portion of a chuck section; a transfer mechanism for reciprocatively transferring said bobbin grasping device between the rotary hook and the bobbin stock section; and an orientation change mechanism for, in a position near one end of a stroke of transfer by said transfer mechanism of said bobbin grasping device, changing an orientation of the chuck section of said bobbin grasping device, being transferred toward the rotary hook, so that the chuck section is oriented toward the rotary hook, and changing the orientation of the chuck section of said bobbin grasping device, being transferred toward the bobbin stock section, so that the chuck section is oriented toward the bobbin stock section; wherein said bobbin grasping device includes a moving member linearly movable by said transfer mechanism in a reciprocative manner in a first direction and second direction opposite said first direction and said chuck section is pivotally supported on said moving member, a spring member for normally biasing said chuck section so that said chuck section is oriented in said first direction, and an actuating member provided in said bobbin grasping device in such a manner that said actuating member pivots together with said chuck section; wherein said orientation change mechanism includes a projection provided near the one end of the stroke of transfer, said projection causing the distal end portion of said chuck section to be oriented in said second direction by said actuating member abutting against said projection, during the transfer in said second direction of said bobbin grasping device, so that said actuating member pivots against a biasing force of said spring member, and an engaging mechanism for, at the one end of the stroke of transfer, engaging with said chuck section, oriented in said second direction, to thereby keep said chuck section oriented in said second direction; wherein said actuating member of said bobbin grasping device includes first and second engaging arms provided at respective predetermined angles with respect to a pivot shaft of said chuck section, and said projection of said orientation change mechanism comprises first and second projections spaced apart from each other along the stroke of transfer near the one end of the stroke of transfer; and wherein, during the transfer in said second direction of said bobbin grasping device, the first engaging arm abuts against the first projection so that said actuating member is caused to pivot against the biasing force of said spring member and then the second engaging arm abuts against the second projection and so that said actuating member is caused to further pivot against the biasing force of said spring member, whereby the distal end portion of said chuck section is oriented in said second direction.