The present invention provides an embroidery frame having at least three sections. The three sections are base section, an alignment section, and a retention section. The alignment section is configured to be positioned on the base section prior to the positioning of the retention section thereon. The retention section is configured to be engaged with the alignment section such that the alignment of the retention section with the base section is determined by the alignment of the alignment section with the base section. At least one of the alignment section and the retention section is configured to be magnetically attached to the base section.

The present invention provides an embroidery frame that has at least three sections. The at least three sections include a base section that defines a perimeter. An alignment section is configured to be positioned on the base section such that it covers a first portion of the perimeter of base section while leaving a second portion of the perimeter of the base section uncovered. A retention section that is configured to cover the second portion of the perimeter of the base section. The retention section is configured be engaged with the alignment section such that alignment of the retention section with the base section is determined by alignment of the alignment section with the base section. At least one of the alignment section and the retention section is configured to be magnetically attached to the base section.

In an automated bobbin-exchanger device (3), a guide groove (6) which is provided on a vertical transfer base (5) has a horizontal portion (6a), a vertical portion (6c) and an arcuate portion (6b). A bobbin chuck (18) reciprocally moves pivotably along the guide groove (6) to make a travel distance minimum, thus enabling users to quickly exchange the bobbin case (12). By placing a bobbin holder (13a), a chuck-drive lever (14) and a chuck-drive air-cylinder (26) circumferentially, it is possible to make a whole structure compact and space-saving. The bobbin-exchanger device (3) requires only two bobbin cases (12) available to make their check and maintenance easy.