Abstract: An overlock sewing machine includes a main shaft fixing operating arm provided with a shaft pin engaging portion that engages with a fixing inner shaft pin and an arm provided to be operable by a user which are integrally rockable within a specified range, and further includes a main shaft fixing operating spring which urging direction is switched in both directions of an rocking direction by exceeding a neutral point by the rocking movements of the main shaft operating arm and the arm.

Abstract: An overlock sewing machine includes a main shaft fixing operating arm provided with a shaft pin engaging portion that engages with a fixing inner shaft pin and an arm provided to be operable by a user which are integrally rockable within a specified range, and further includes a main shaft fixing operating spring which urging direction is switched in both directions of an rocking direction by exceeding a neutral point by the rocking movements of the main shaft operating arm and the arm. Further, a switching cam ring is fixed to the main shaft fixing operating shaft that obtains driving force upon abutment of a slide plate pin of the slide plate to rotate the main shaft fixing operating shaft.

Abstract: An overlock sewing machine includes a main shaft fixing operating arm provided with a shaft pin engaging portion that engages with a fixing inner shaft pin and an arm provided to be operable by a user which are integrally rockable within a specified range, and further includes a main shaft fixing operating spring which urging direction is switched in both directions of an rocking direction by exceeding a neutral point by the rocking movements of the main shaft operating arm and the arm.

Abstract: A buttonhole presser device includes a fabric presser unit; a fabric feed frame unit including a start position detecting member and an immovable receiving portion, the fabric feed frame unit being slidable relative to the fabric presser unit between a start position and an end position of the buttonhole; a button-diameter measuring unit including an end position detecting member and a movable receiving portion, the button-diameter measuring unit being configured to grip a button by being slid relative to the fabric feed frame unit; and a fixing unit that fixes the button-diameter measuring unit to the fabric feed frame unit when the button-diameter measuring unit is gripping the button between the immovable receiving portion and the movable receiving portion and that allows the button to be removed after the button-diameter measuring unit has been fixed to the fabric feed frame unit.

Abstract: An object of the present invention is to provide an embroidery cloth presser which prevents a needle thread from being sandwiched between the embroidery cloth presser and a cloth to allow an embroidery frame to move smoothly and which also prevents inappropriate draw-in of the needle thread, that is, prevents a cross-over thread of the needle thread resulting from long-distance movement of the embroidery frame from remaining on an embroidery surface. An embroidery cloth presser is installed on a presser bar of a sewing machine to press a cloth to be embroidered and which includes a projection provided on a bottom surface of the cloth presser which contacts the cloth around a needle and forming, between the cloth presser and the cloth, a gap through which a needle thread passes.

Abstract: In a sewing machine having an automatic thread cutting mechanism, a situation of a thread cutting operation is detected in power-OFF to continuously carry out a proper operation when a power supply is turned ON again after sudden power-OFF. In a sewing machine having an automatic thread cutting mechanism, there is provided means for detecting an operation situation of the automatic thread cutting mechanism when a power supply is turned ON. Based on a signal for the detection, the automatic thread cutting mechanism is operated to complete a thread cutting operation and to carry out a control to return into an initial state when a stop is performed with the thread cutting mechanism in power-ON executing the thread cutting work.

Abstract: Disclosed is an automatic thread cutting device for a sewing machine which is provided with a horizontal loop taker, wherein a thread catching member (4) is operated in response to a thread cutting instruction to reciprocatingly move with a movable blade (5) along a predetermined course, the thread catching member (4) normally catching the upper thread when moving in the return-way of reciprocation to guide the upper thread to a fixed blade (14) which is provided to cut the upper thread in cooperation with the movable blade (5), and wherein a thread regulating means is provided to cut the lower thread (29d) together with the upper thread, the thread regulating means being operated to press down the lower thread (29d) to a position where the lower thread (29d) is caught by the thread catching member (4) in addition to the upper thread when the thread catching member (4) is moving in the return-way of reciprocation.

Abstract: A free work pressing device for a sewing machine includes a holding portion for mounting the free work pressing device to the presser bar of sewing machine, a slide shaft supported by the holding portion and being slidingly movable in the axial direction, a work pressing foot secured to the lower end of the slide shaft, an elastic member for normally pressing the slide shaft axially in the downward direction relative to the holding portion, an adjust mechanism for adjusting the vertical position of the work pressing foot relative to the work which is to be stitched. The work pressing foot is smoothly movable as yielding up and down in dependence upon a variation in the thickness of the work against and under control of the elastic member.

Abstract: Disclosed is an automatic thread cutting device for a sewing machine which is provided with a horizontal loop taker, wherein a thread catching member 4 is operated in response to a thread cutting instruction to reciprocatingly move with a movable blade 5 along a predetermined course, the thread catching member 4 normally catching the upper thread when moving in the return-way of reciprocation to guide the upper thread to a fixed blade 14 which is provided to cut the upper thread in cooperation with the movable blade 5, and wherein a thread regulating means is provided to cut the lower thread 29d together with the upper thread, the thread regulating means being operated to press down the lower thread 29d to a position where the lower thread 29d is caught by the thread catching member 4 in addition to the upper thread when the thread catching member 4 is moving in the return-way of reciprocation.

Abstract: Disclosed is a free work pressing device for sewing machine which is simple in structure and smooth in operation. As to the variation in the thickness of the work (18), the work pressing foot (C) is smoothly movable as yielding up and down in dependence upon the variation in the thickness of the work against and under the control of the elastic member (14). The free work pressing device sewing machine comprises a holding portion (A) for mounting the free work pressing device to the presser bar (16) of sewing machine, a slide shaft (5) supported by the holding portion (A) and being slidingly movable in the axial direction, a work pressing foot (C) secured to the lower end of the slide shaft (5), an elastic member (14) for normally pressing the slide shaft (5) axially in the downward direction relative to the holding portion (A), an adjust mechanism (B) for adjusting the vertical position of the work pressing foot (C) relative to the work (18) which is to be stitched.

Abstract: In a sewing machine having an automatic thread cutting mechanism, a situation of a thread cutting operation is detected in power-OFF to continuously carry out a proper operation when a power supply is turned ON again after sudden power-OFF. In a sewing machine having an automatic thread cutting mechanism, there is provided means for detecting an operation situation of the automatic thread cutting mechanism when a power supply is turned ON. Based on a signal for the detection, the automatic thread cutting mechanism is operated to complete a thread cutting operation and to carry out a control to return into an initial state when a stop is performed with the thread cutting mechanism in power-ON executing the thread cutting work.

Abstract: A sewing machine with an embroidery stitching function is disclosed, wherein a needle is vertically reciprocated to form stitches on a work held by an embroidering frame (19) which is moved in X-Y directions by a frame moving device relative to the needle on a working surface (2a) of a working bed (2), the frame moving device being composed of composed of a first mechanism (A) for moving said embroidering frame in the Y direction and a second mechanism (B) for moving the embroidering frame in the X direction, the first mechanism (A) being located on the working surface and connected to the embroidering frame (19) and the second mechanism (B) being housed in the sewing machine, the first mechanism (A) being moved by the second mechanism (B) to one end of the working bed (2) where the first mechanism (A) is rotated to a retreated position at the time of carrying out the ordinary stitching operation.

Abstract: An overlock sewing machine has a movable cutter which is activated in association with rotation of a main drive shaft to cooperate with a fixed cutter provided in the same plane with an upper surface of a needle plate, to thereby cut a work while the work is being stitched. A link mechanism includes a drive link having one end rotatably connected to a mount and the other end is connected to the movable cutter and a swingable link having an arcuate guide groove extending between one end and a center axis thereof around which the swingable link is swingingly moved. The drive link has a point between opposite ends thereof operatively connected to the arcuate guide groove of the swingable link. An operating device includes an operating shaft which is operatively connected to the point of the drive shaft so that the point of the drive link may be substantially moved along the arcuate guide groove of the swingable link between said one end and center axis thereof by manipulation of an operating knob.

Abstract: A lock stitch sewing machine with an automatic thread tension adjusting device is disclosed, wherein the sewing machine has a plurality of thread tension adjusting mechanisms 7, each of which including a pair of thread tension disks 12, 13, one of which is normally pressed by a spring toward the other. A sensor 4 is responsive to the operation of a thread tension releasing lever 20 made by a user with a slight touch applied thereto to give a signal. A CPU1 is responsive to the signal to compare the value of the existing thread tension of the thread tension adjusting mechanisms 7 with a predetermined one. If the value of the existing thread tension is higher than the predetermined one, the CPU1 is operated reduce the value of the existing thread tension to a predetermined one. Thus the tension releasing operation ability is increased.

Abstract: This invention relates to a computer controlled sewing machine, and more particularly to such a sewing machine which is incorporated therein with a plurality of feed adjusting switches for giving information to a micro-computer housed in the sewing machine, in order to correct irregularities of forward and backward feed amounts.

Abstract: A polychrome printing platen of a printer having a platen shaft comprises an axially elongated platen body rotatably mounted on the platen shaft and having a plurality of grooves formed therein to extend in the axial direction and spaced from each other in the circumferential direction, and a plurality of permanent magnets each arranged in each of the grooves. A plurality of axially elongated elements having inks of different colors impregnated therein are attached to the platen body. Each ink impregnated element has an upper face and a lower face and has a magnetizable plate secured to the lower face thereof. All ink impregnated elements are detachably attached to the platen body by the permanent magnets which attract the magnetizable plates.

Abstract: A sewing machine has a loop taker rotated in horizontal plane and a bobbin carrier contained in the loop taker. The bobbin carrier has an abutment secured thereto and a leaf spring mounted on the abutment and movable to and away from the abutment to adjust a tension applied to a lower thread extending between the abutment and the leaf spring. A plurality of windings are provided on a stationary horizontal plane adjacent the underside of the loop taker. The windings are progressively energized by selective operation of an electric control part to create a revolving magnetic field. A magnet is rotated in accordance with the revolving magnetic field, and the rotation of the magnet is transmitted through a series of gears to a cam which actuates a member influencing the movement of the leaf spring, thereby adjusting the tension applied to the lower thread.

Abstract: A process for stitching a buttonhole in the forward and reverse fabric feeding directions by means of a zigzag sewing machine including the step of producing one or more of stitches at a critical pattern changing point which will serve as a reference mark for enabling the sewing machine operator to operate the sewing machine as required with ease for the pattern changing operation.

Abstract: An electronic sewing machine includes at least two pulse motors, in which a control detecting device detects all individual operations of the movable members in response to a plurality of functions performed by independent driving sources, such that in each of these functions the machine operates normally. The control detecting device includes two screen interrupting elements each associated with the respective pulse motor and a single photoelectric sensor cooperating with each interrupting element for producing electric signals for operating a microcomputer of the sewing machine to set each of the pulse motors to an initial position.

Abstract: An electromagnetic driving device is provided at a non-rotating part of a sewing machine, thereby to rotate a first magnet via transmission mechanism. A second magnet which is opposite to the first magnet with an appropriate space thereby, is rotatably provided with respect to a bobbin carrier. These magnets keep a certain one rotating relative position by means of the opposing magnetic poles, thereby to transmit rotation of the first magnet to the second magnet. Rotation of the second magnet actuates a tension adjusting mechanism comprising a thread tension adjusting spring provided on the bobbin carrier, via the transmission mechanism so as to adjust the thread tension, and controls the electromagnetic driving device in response to designation of the thread tension. Thus, the tension of the lower thread may be adjusted when attaching the bobbin carrier in the sewing machine.