JPS647796B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic copy sewing machine that automatically forms stitches along a stitch formation reference line marked on a work cloth.

Conventionally, when using a sewing machine to form a seam along the line of a mark placed at a predetermined position on a workpiece cloth, the operator needs to delicately adjust the feeding direction of the workpiece cloth while feeding it along the line of the mark. Therefore, it is difficult for people who are not familiar with sewing machines to form accurate stitches along the marked lines.

The present invention has focused on the above points, and an object of the present invention is to provide an automatic copy sewing machine that can automatically form stitches along a stitch formation reference line marked on a work cloth.

Embodiments of the present invention will be described below based on the drawings. FIG. 1 is a perspective view of the automatic copying sewing machine, and FIG. 2 shows the peripheral portion of the needle. As shown in FIG. 2, a detector 4 is arranged on the presser foot 2 attached to the lower end of the presser bar 3 to optically detect the seam formation reference line 5 marked on the work cloth 20. ing. As shown in FIGS. 2 and 3, this detector 4 is located above the opening of the presser foot 2 close to the drop point of the needle 1, and has a group of optical fibers 4 with its lower surface as a light entrance surface.
a are arranged in a line parallel to the swinging direction of the needle and are installed in the detector 4, and furthermore, a light source 4b for projecting light is arranged on the lower surface of the detector 4.

This sewing machine has the function of forming a plurality of stitch patterns by selection, the needle 1 can be oscillated in the horizontal direction by an amplitude actuator 11 (described later), and the feed dog 13 in the throat plate is controlled by a feed actuator 12. , has a structure in which the work cloth is fed back and forth in synchronization with the up and down reciprocating movement of the needle 1.

Furthermore, the control and drive circuit including the automatic copying mechanism of this sewing machine will be explained with reference to the block diagram of FIG. The light incident from the sewing machine converts the light into a digital signal using a light receiving element or the like, and outputs this signal to the information processing control circuit 8 as position information of the seam forming reference line 5 on the work cloth. A timing pulse generator 7 is connected to the main shaft of the sewing machine and generates a timing pulse for each stroke in response to the up and down reciprocating movement of the needle 1. Reference numeral 9 denotes a stitch information memory, which stores the stitch data of all stitch patterns instructed by the stitch pattern instruction display 14 disposed on the front of the sewing machine frame as digital signals, and stores the stitch data of all the stitch patterns instructed by the stitch pattern instruction display 14 arranged on the front of the sewing machine frame. The digital signal is output to the information processing control circuit 8. Here, the information processing control circuit 8 reads a position detection signal representing the position of the stitch forming reference line 5 from the detector 4 in response to a timing pulse when an automatic copying operation switch 15 (described later) is on, The swing position of needle 1 is determined according to the signal, and needle 1 is placed at that position.
The stitch forming drive control circuit 10 is configured to send a position command signal to the stitch forming drive control circuit 10 to cause the stitch forming drive control circuit 10 to swing. This position command signal for the needle position is calculated and generated based on the stitch information data sent to the information processing control circuit 8 and the position detection signal from the detector 4. Further, the information processing control circuit 8 sends a feed command signal for feeding the work cloth as well as a position command signal for determining the swinging position of the needle to the stitch forming drive control circuit 10.
The stitch forming drive control circuit 10 is configured to operate an amplitude actuator 11 and a feed actuator 12 based on these command signals, and the amplitude actuator 11 swings the needle 1 in the lateral direction by a specified width to control the feed. Actuator 12 is feed dog 1
3 is configured to apply a specified amount and direction of feed motion to the work cloth. Note that 15 is a switch for automatic copying operation installed near the stitch pattern indicator 14, and 16 is a main switch for starting and stopping the sewing machine.

Next, the operation of this automatic copy sewing machine will be explained.

First, a seam formation reference line 5 is attached on the work cloth 20 using a material that reflects light. Insert the work cloth under the presser foot 2 to form a seam on this seam formation reference line 5, turn on the automatic copying switch 15, turn on the main switch 16, and turn on the information processing control circuit 8. Activate it and start the sewing machine. Information regarding the stitch pattern designated by the stitch pattern instruction display 14 is read out from the stitch information memory 9 to the information processing control circuit 8, and at the same time, the information about the stitch pattern specified by the stitch pattern instruction display 14 is read out from the detector 4.
A position detection signal representing the position of is input to the information processing control circuit 8 via the photoelectric converter 6. The information processing control circuit 8 calculates the swinging position of the needle 1 from the stitch data related to stitch formation and the position detection signal, and sends a signal for commanding the needle swing position and a feed command signal for the work cloth from the timing pulse generator 7. is outputted to the stitch forming drive control circuit 10 in accordance with the timing pulse. That is, when the position of the reference line 5 detected by the detector 4 is shifted to the left or right from the center, the needle 1 is swung around this shifted position to form a predetermined stitch pattern. A needle oscillation position command signal is output. Then, a drive signal output based on the position command signal is applied from the stitch forming drive control circuit 10 to the amplitude actuator 11 and the feed actuator 12, and a stitch of the specified pattern is formed along the stitch forming reference line 5. The swinging position of the needle 1 and the feeding motion of the feed dog 13 are controlled and driven so that the movement of the needle 1 is controlled. The swinging motion of the needle 1 is performed while the needle 1 is above the sewing machine bed, and the amount of feed by the feed dog 13 and the direction of the feed are controlled and determined when the needle 1 is below the sewing machine bed.

As described above, according to the automatic copy sewing machine of the present invention, a detector for detecting the position of the stitch formation reference line attached to the workpiece cloth near the needle drop point of the sewing machine is disposed on the presser foot. A position command circuit that outputs a position command signal to position the needle along a stitch forming reference line in accordance with the position detection signal, and a drive device that swings the needle in accordance with the position command signal from this circuit are provided. Because of this structure, sewing work including pattern stitching in which stitches are formed along the reference lines marked on the work cloth can be extremely easily performed.

In addition, according to the automatic copy sewing machine of the present invention, since the detector is placed on the presser foot so as to be close to the stitch formation reference line, processing can be performed without being affected by ambient light such as the sun or a sewing machine lamp. Stitches can be reliably formed along reference lines marked on cloth.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, in which Fig. 1 is an external perspective view of a sewing machine, Fig. 2 is a perspective view showing a detector placed close to the needle, and Fig. 3 is a line on the seam formation reference line of the work cloth. FIG. 4 is a plan view of the presser foot located at the presser foot, and FIG. 4 is a block diagram of the control drive circuit including the automatic copying mechanism. DESCRIPTION OF SYMBOLS 1... Needle, 4... Detector, 4a... Optical fiber group, 4b... Light source, 5... Stitch formation reference line,
6... Photoelectric converter, 7... Timing pulse generator, 8... Information processing control circuit (position command circuit),
11...Amplitude actuator (needle drive device).

Claims (1)

[Scope of Claims] 1. A needle capable of vertical reciprocating motion and lateral movement within a predetermined range, and a feeding device that imparts a feeding motion to the work cloth in time with the vertical reciprocating motion. In a sewing machine equipped with the above-mentioned sewing machine, a needle is placed on the presser foot near the needle drop point in order to detect the stitch forming reference line marked on the work cloth and generate a position detection signal indicating the position of the reference line. a detector; a timing pulse generator that generates a timing pulse in synchronization with the vertical reciprocating motion; and a timing pulse generator that reads the position detection signal in response to the timing pulse and causes the needle to follow the stitch formation reference line. The needle is characterized by having a position command circuit that creates and outputs a position command signal based on a position detection signal in order to position the needle, and a drive device that swings and positions the needle according to the position command signal. Automatic copy sewing machine. 2. The detector includes a light source, an optical fiber group that receives reflected light from the reference line, and light from the optical fiber group to optically detect a seam formation reference line attached with a light-reflecting material. and a photoelectric converter for converting into an electrical signal, the optical fiber group being characterized in that the optical fiber group is a large number of optical fibers whose ends are arranged in a line parallel to the direction of oscillating movement of the needle. An automatic copy sewing machine according to claim 1.