Description MULTIHEAD QUILTING MACHINE

Technical Field

[1] The present invention relates to a multihead quilting machine capable of significantly enhancing productivity and quality of quilting works, and in particular, to a multihead quilting machine, which allows a movement distance of a fabric transfer roller to be decreased, allows a quilting distance of a sewing device to be increased, minimizes an impact resulting from inertia due to acceleration and stopping operations of main components of the multihead quilting machine in operation, thereby preventing overrun from occurring, significantly enhancing a quality of the quilting operation and a quilting speed by reducing an operational load of the sewing device, and increasing productivity.

[2]

Background Art

[3] In general, a sewing machine, which is also referred to as a quilting machine, acts to sew an outer material and a lining material with cottons fixed between the outer material and the lining material after inserting the cottons therebetween, and is usually used for production of clothes with cottons or bed clothes such as sheet, cushion, bed, matelasse or coverlet.

[4] To explain essential components of the sewing machine, it may be composed of a fabric transfer roller which inserts cottons between the outer and lining materials and supplies them toward a plurality of sewing devices, and a head having the sewing devices for carrying out sewing at a constant interval on the transferred fabric. In order for the quilting machine to form various quilted patterns on the fabric, needles mounted on the head of the sewing device must be moved in front, back, right, and left directions on the fabric.

[5] To this end, the conventional quilting machine has a pair of fabric transfer rollers mounted on respective front and back surfaces of the machine to supply the fabric with cottons inserted between outer and lining materials in a Y-axis direction while moving a roller support connecting the pair of fabric transfer rollers in an X-axis direction (i.e., a right or left direction) using a position control motor as shown in FIG. 1 so that sewing can be usually carried out on the fabric in front, back, right, and left directions.

[6] In addition, in a case of sewing device mounted on the head, a thread take-up device is mounted thereon for pulling and releasing the thread at the time of driving the sewing device. However, the number of the thread take-up devices is increased as several sewing devices are mounted, so that the thread take-up devices are connected

one rod, and a cam is mounted on an end of the rod to carry out ascent and descent of the thread take-up device, which is the most usual mode of the sewing device. [7]

Disclosure of Invention

Technical Problem

[8] When the conventional quilting machine moves the fabric transfer roller in an X- axis direction (i.e., a right or left direction), there arises many limitations on increase of a movement speed of the quilting machine, so that it was difficult to enhance productivity.

[9] That is, according to the conventional quilting machine, in order to move the fabric in an X-axis direction by means of a fabric transfer roller, a roller support, a screw rod, a transfer body, or a guide rod is mounted to transfer the roller support connected to the fabric transfer roller using a position control motor in an X-axis direction (i.e., a right or left direction). However, weights of the pair of fabric transfer rollers and the roller support connected to the rollers typically exceed 100kg to 200kg and a direction of the fabric transfer roller must be switched at a speed of 1/20 second in the X-axis direction when a rotational speed of a main axis is 1200rpm for forming quilted patterns. Accordingly, when the movement speed of the fabric transfer roller is increased, load and inertia of the fabric transfer roller significantly occur to bring a significant impact on a transfer portion while noises and vibrations are simultaneously increased to cause a damage on the machine and angled portions of the quilting patterns are not accurately formed due to the inertia when the quilting patterns are formed, so that it was difficult to obtain the enhanced productivity through enhancement of the movement speed of the fabric transfer roller.

[10] Further, thread take-up devices of several sewing devices mounted on the quilting machine are all connected to one connection axis, which is driven by a cam, so that a high friction heat is generated due to a friction between the cam and the axis, and the heat causes a lubricant to be damaged to interrupt a smooth operation of the quilting machine and make it difficult to pave the way for a pleasant working environment due to significant noises resulting from the friction. Furthermore, when the friction continues to cause the connection axis or the cam to be worn, an operation of the quilting machine can not be exactly carried out to cause a limit to a movement speed of the machine.

[H]

Technical Solution

[12] One aspect of the present invention is to provide a quilting machine, which comprises: a head 20, in the middle of a main body 10, with a plurality of sewing

devices 30 having thread take-up devices 301 connected to a connection axis 302 to be driven and spaced apart from each other at a constant interval; a pair of fabric transfer rollers 70 fixed to a roller support 701 and positioned in front and back sides of the main body 10 and moving a fabric to be moved in front and back directions by a driving motor 705; a screw rod 702a connected to a driving axis of a roller position control motor 50 coupled to a transfer body 703a formed integrally with the roller support 701 by means of screws for moving the roller support 701 in right and left directions along a guide rod 704; a transfer body 703 formed on one side of the head 20; and a guide bar 60 formed on a bottom of the head 20, wherein the screw rod 702a coupled to the transfer body 703 by means of screws, is coupled to a rotational axis of a head position control motor 80 to move the head 20 in a right or left direction. The thread take-up device 301 has a link 402 mounted on one end of the connection axis 302 to couple the link 402 to the rotation cam 401, the rotation cam 401 is coupled to a position control motor 40, and an encoder is mounted on the sewing device 30 so that the position control motor 40 can be driven in synchronization with an encoder signal for carrying out operations of the thread take-up devices 301. [13]

Advantageous Effects

[14] According to the present invention, movement distances of a head and a fabric transfer roller associated with quilting distances of sewing devices of a multihead quilting machine can be decreased to a half, impacts due to an inertia resulting from acceleration and stopping operations of main components of the machine in operation can be significantly reduced, and productivity can be significantly increased by reducing an operational load due to a friction of a thread take-up device of a sewing device and enhancing an operational speed.

[15]

Brief Description of the Drawings

[16] FIG. 1 is a plan view illustrating a conventional multihead quilting machine.

[17] FIG. 2 is a plan view illustrating main components of the present invention.

[18] FIG. 3 is a front view illustrating main components of the present invention.

[19] FIG. 4 is a view illustrating mounting of a thread take-up device of the present invention.

[20] FIG. 5 is a front view illustrating another embodiment of the present invention.

[21]

Best Mode for Carrying Out the Invention

[22] FIG. 2 is a plan view illustrating main components of the present invention, and

FIG. 3 is a front view illustrating main components of the present invention. As shown

in the same drawings, the present invention has a pair of fabric transfer rollers 70 mounted on front and back sides of the machine for moving a fabric in front, back, right, and left directions, and has a head 20 for moving in a right or left direction along a guide bar 60 mounted on a main body 10 in the middle of the main body 10.

[23] That is, a servo motor is mounted on one end of a rotational axis of one of the fabric transfer rollers 70 to drive the one fabric transfer roller 70, wherein the two fabric transfer rollers 70 are coupled to each other by a timing belt, so that the fabric transfer rollers 70 can be simultaneously driven even when one fabric transfer roller 70 is driven by the servo motor, thereby transferring the fabric in a Y-direction (i.e., a front or back direction).

[24] In addition, a roller support 701 is mounted between the two fabric transfer rollers

70 to allow the fabric transfer rollers 70 to move at the same time, a screw rod 702a driven by the roller position control motor 50 is mounted on one side of the roller support 701 to couple a transfer body 703a formed integrally with the one side of the roller support 701 coupling the fabric transfer rollers 70 to each other to the screw rod 702a, a guide rod 704 is mounted on front and back sides of the main body 10 to allow the roller support 701 to move along the guide rod 704, so that the fabric transfer rollers 70 can be freely moved in an X-axis direction, that is, a right or left direction using the roller position controller motor 50.

[25] Meanwhile, a transfer body 703 is mounted on one side of the head 20, a screw rod

702a coupled to the transfer body 703 by means of screws is mounted on one side of the main body 10, and then the screw rod 702a is driven by the head position control motor 80, so that positions of the head can be moved in the X-direction (i.e., a right or left direction).

[26] Accordingly, the fabric transfer rollers 70 can be moved in the X-axis direction using the roller position control motor 50 and the head 20 having several sewing devices 30 can also be moved in the X-axis direction using the head position control motor 80, so that these two position control motors 50 and 80 can be properly controlled at the time of operating the quilting machine, thereby decreasing a movement distance of the head 20 or the fabric transfer roller 70 to a half of a quilting distance of the sewing device 30 mounted on the head 20.

[27] That is, when a quilted pattern of 10cm in length needs to be formed in the X-axis direction by the sewing devices 30 mounted on the head 20, the fabric transfer roller 70 must be moved by 10cm in the X-axis direction when the head 20 of the conventional quilting machine is fixed, however, the fabric transfer roller 70 of the present invention can move in the negative X-axis direction, that is, by 5cm in a left direction and the head 20 of the present invention can move in the positive X-axis direction, that is, by 5cm in a right direction, so that a displacement value of the movement between the

head 20 and the fabric transfer roller 70 becomes 10cm in total, and thus the length of the quilted pattern using the sewing machines 30 becomes 10cm, which is a half of the distance of the head 20 and the fabric transfer roller 70 of the conventional quilting machine, thereby reducing a time required for moving the head 20 or the fabric transfer roller 70 in a right or left direction to a half.

[28] Such a reduction in time can reduce an inertia from a movement start point to a movement end point of the head 20 and the fabric transfer roller 70 so that an impact due to the inertia can be significantly reduced compared to the conventional quilting machine and a lifetime of main components of the transfer portion can be significantly lengthened, and can also significantly reduce a load even when a movement direction of the head 20 and the fabric transfer roller 70 are rapidly changed so that angled portions in a case of quilted patterns having angled parts can be exactly represented and a resultant quality of the quilted pattern can be significantly enhanced.

[29] In addition, thread take-up devices 301 mounted on the sewing devices 30 of the head 20 are coupled to the connection axis 302, a link 402 is mounted on one end of the connection axis 302, the link 402 is coupled to a rotation cam 401, the rotation cam 401 is coupled to a position control motor 40, an encoder is mounted on the sewing device 30 to allow the position control motor 40 to be synchronized with the encoder in accordance with an encoder signal for carrying out operations of the thread take-up devices 301, so that frictions occurring when the connection axis 302 is operated by the position control motor 40 can be significantly reduced, thereby reducing noises, operational loads, and an operation speed of the thread take-up device 301, which leads to enhanced productivity.

[30] Meanwhile, the head 20 is moved by the head position control motor 80 and the fabric transfer roller 70 is moved by the roller position control motor 50 in accordance with the present invention, however, it should be noted that the present invention is not limited thereto.

[31] That is, as in the embodiment of the present invention described and illustrated in

FIG. 5, the head 20 and fabric transfer roller 70 can be configured to be simultaneously driven in reverse directions to each other by one position control motor instead of the respective position control motors.

[32] To this end, belt pulleys 901 and 902 are mounted on the driving axis of the head position control motor 80 and the screw rod 702 moving the head 20 in a right or left direction, and a connection axis 90 is mounted for delivering a power between the belt pulleys as shown in FIG. 5, so that the head 20 and the fabric transfer roller 70 can be moved in reverse directions to each other using one motor. However, it should be apparent that not only a connection axis can be used but also a type similar to that can be used.