JPS5875588A - Fabric sending control apparatus of sewing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cloth feeding device for a sewing machine, and in particular, a feeding adjuster supported on a machine frame so as to be rotatable around a fixed axis is rotated & I by a stepping motor, and its rotational position is The present invention relates to a cloth feed control device for a sewing machine that changes the cloth feed direction and amount of a feed dog in accordance with the above.

Recently, with the computerization of sewing machines, the regulator is displaced via a stepping motor whose rotation is controlled based on cloth feed information stored in a memory device, and the selected pattern is sewn at a predetermined stitch pitch. Ten shots were fired that made it possible.

Recently, in the fabric feed device of a sewing machine, when reversing the feed direction in conjunction with the operation of the bank stitch switch, the 1-step motor is switched to "normal feed" while the feed dog is sinking below the throat plate. The rotational displacement occurs from the area to the ``reverse feed'' area all at once, but especially when changing from the state of ``normal feed'' at the maximum feed pitch to the ``reverse feed'' state of the sewing machine, the rotation of the step motor As the corner becomes maximum, the step motor cannot follow the sewing speed of the sewing machine,
This has the disadvantage that the reverse stitches are misaligned with the normal feed stitches, making the stitches unsightly and reducing the quality of the product.

This invention uses a stepping motor to generate an initial position signal after operating the back stitch switch in relation to the operation of the back stitch switch and the position signal generated while the feed bacteria are sinking downward from the top surface of the bed. During the period, the cloth feed pinch is rotated to the position where it is zero, and the next position signal is generated aJ
It is an object of the present invention to solve the above-mentioned drawbacks of the conventional method by rotating the cloth to two positions with the cloth feeding direction "reverse" during rlJJ.

Embodiments of the present invention will be described below with reference to the drawings.

The sewing machine l according to the present invention has sewing information corresponding to a plurality of stitch patterns stored in advance in the storage device 2 of the microphone computer MC, and the front surface of the horizontal arm la can be fixed by pressing a push button 8 arranged thereon. The pattern selected each time the pressing time elapses is displayed on the display panel, and can be moved one by one to the right or left in the arrangement order of the display section 5. In this way, the selected pattern can be sewn by pressing the button 6. This is a known sewing machine that can be stopped by pressing. The mechanical structure of the main part of this invention is shown in Section 11V, and the electrical structure is shown in FIG. 2.4.

In the horizontal arm la, the main shaft 7 is rotatably supported around the - fixed m line, and although not shown, there is a needle holder on the left side of FIG. 1 for vertically moving the needle bar 8! The vI+h structure is connected, a hand pulley 9 is fixed to the right side protruding from the machine frame, and an eccentric cam 11 for horizontally moving the false tooth 10 is fixed in the middle of these, and a It is connected to the installed sewing machine motor 12 via a bell 13 so as to rotate continuously in one direction.

The feed dog lO has a forked part that loosely fits into the eccentricity h15 of the vertical feed shaft 14 which is connected to the main shaft 7 and rotates in synchronization with the vertical movement of the fixed rod 8, and a vertical arm part 17 of the horizontal feed shaft 16. The cloth placed on the upper surface of the ped 1b is transferred in one direction by fixing it in the middle of the feed table 18, which has a connecting part connected to the upper end, and in cooperation with the rotation of the eccentric part 150 and the swinging of the vertical arm part 17. Create & l as you like.

The horizontal feed shaft 16 can be oscillated in the direction of rotation in synchronization with the vertical movement of the needle bar 8 by means of a feed control means 19. That is, the lower end of the continuous link 20, which has a forked part 20a surrounding the eccentric cam 11 at the upper end and a guide pin 20b installed in the middle parallel to the main shaft 7, is connected to the horizontal feed shaft 1.
A stepping motor (pulse motor) 22 is supported within 1slc so that its output shaft 22a is parallel to the guide pin 20b. An adjuster 24 having a guide groove 24a for fitting and guiding a square piece 28 rotatably supported by a guide pin 20b is fixed to one end of the output shaft 22a.

The relationship between the regulator 24 and the feed dog 18 is the same as that of the guide 12.
When 4a is flat as shown in FIGS. 1 and 3, the horizontal movement of the feed dog 10 is stopped.

Note that the "+" shown in Figure 8 indicates "forward feed" and "-"
" indicates "reverse feed," and the numbers from 0 to 44 indicate the size of the feed pitch. 0 This sewing machine also uses a feed pulse generator as a position detector to detect the fabric feed period. 27 (FIG. 2), an origin detector 86 that detects a state in which the inclination of the loop tube 24 matches rOJ in FIG. 8 (horizontal state of the groove 24a) as the origin of the pulse motor 22, and a cloth feed pitch. The 0-feed pulse generator 27, which is equipped with a feed dial 87 for changing the rotation speed, is fixed to the main shaft 7, has a large diameter portion 25a approximately half the circumference, and has the other portion rotated more than the large diameter portion 25a. The rotary plate 25 has a small diameter portion 25b with a short diameter from the center of movement, and is supported on the machine frame opposite the rotary plate 25, and while facing the small diameter portion 25b, a high level It consists of a detector that generates a signal and logically generates a low level signal while facing the large diameter portion 25a.The origin detector 86 is not shown, but is fixed to the output of the pulse motor 22 @22a. It consists of a disc in which a radial notch is formed, and a detector that faces the notch and generates an origin signal when the slope of the groove 24 & of the adjuster 24 becomes horizontal.

Next, regarding the circuit diagram of FIG. 2, a feed pulse generator 27 is connected to the input section of a known microcomputer (microcomputer) MC as a control circuit consisting of a central processing unit (calculating unit) 28 and a storage device 2. , a pattern selection switch 29 corresponding to the push button 8 , a start/stop switch 80 corresponding to the push button 6 , a back stitch switch 82 corresponding to the push button 81 , an origin detector 86 , and a feed dial 37 and the corresponding feed adjustment switch 38. In addition, the output section of the microcomputer MC includes control circuits 3B and 3.
4.85, the sewing machine motor 12, the needle swing pulse motor 86 for horizontally swinging the needle bar 8, and the feed pulse motor 22 are connected. The storage device 2 is a known RA as a means for temporarily storing the signal of the feed adjustment switch 88.
M, and a well-known ROM in which sewing information corresponding to each pattern and programs related to pattern selection, back stitching, and other sewing are fixedly stored. The details of the microcomputer MC (D) will be explained below along with its operation.

When the button 8 is pressed to select a predetermined needle swing pattern, the arithmetic unit 28 reads out the sewing information at the start address of the corresponding pattern from the storage device 2, and the needle bar 8
is set to the initial position of the selected pattern via the oscillating pulse motor 86, and the 1Iiifln unit 24 is set to the initial position downward to the right in FIGS. 1 and 8 via the feed pulse motor 22. From this state, push button 6
When pressed, the main shaft 7 rotates, and while the needle bar 8 moves up and down and the needle 26 is positioned above the ped 1b, that is, the large diameter portion 25a of the rotating plate 25 faces the detector 26. During this time, the fabric is swung, and the feed dog 10 operates to feed the fabric in the forward direction, sewing a predetermined pattern.

Note that the cloth feed pitch in this sewing is determined by rotationally controlling the feed pulse motor 22 based on the sewing information sequentially read out from the storage device 2 and changing the inclination of the guide groove 24a of the adjuster 24. be done.

Also, when a straight line pattern is selected using push button 3, needle bar 8
is fixed at a predetermined position, and the adjuster 24 is fixed in a rightward downward position corresponding to the setting position of the feed dial 87. From this state, if the push button 6 is pressed to operate the sewing machine 1, the thread is fed forward to the rear of the sewing machine as shown in FIG. .

Next, when push button 81 is pressed, back stitch switch 8 is pressed.
2 is activated, and as a result, if the needle swing pattern is selected, the output of sewing information corresponding to the selected pattern is prohibited during the pressing period, and the output of sewing information corresponding to the program and back stitching information stored in the ROM is prohibited. The oscillation of the needle n8 is fixed at the center of its amplitude, and the regulator 24 is fixed at a specific upward-right position (for example, the position corresponding to the scale "-1" in FIG. 3). When the push button 81 is pressed in the selected state, the feed direction is reversed at the feed pitch selected with the feed dial 37. That is, when the push button 81 is pressed from a state where the inclination of the adjuster 24 corresponds to the scale "+4" as shown by the solid line in FIG. -4'' via the feed pulse motor 22.

The above-mentioned control of the regulator 24 must be executed during the period when the feed dog 10 is sinking from the upper surface of the ped 1b in relation to the signal from the feed pulse generator 27, but in relation to the pressing of the push button 81, First, during the first period under the feed stroke method, the feed pulse motor 22 rotates and stops the Wi device 24 at position 1, which is a horizontal state corresponding to the scale "0", and when the feed pitch is "0", After the first stroke is formed, during the next feeding period, the feed pulse motor 22 rotates the adjuster 24 to a position corresponding to scale "-4".

A flowchart illustrating these actions in detail is shown in FIG.

As described above, according to the present invention, in the cloth feed control device for a sewing machine, the regulator for controlling the cloth feed direction and the cloth feed pitch by the feed sheet is rotationally displaced by a stepping motor in response to the rotational displacement. The stepping motor is moved in relation to the back signal to a position where the cloth feed pitch is zero between the formation of the next seam, and then further between the formation of the seam and the formation of the next seam. The back stitch switch is operated while sewing while feeding the stones in the square direction at the maximum feed pitch, especially in straight line patterns, by turning the cloth to the position where the cloth feed direction is reversed.
In this regard, even when the rotational displacement of the stepping motor is the largest, such as when knitting while feeding the fabric in the opposite direction at the same maximum feed pitch as above, during the period when the feed dog is sinking below the top surface of the bed. Since the rotation of the stepping motor can be controlled only when the sewing machine rotates, it is possible to obtain products with beautiful seams with uniform stitch pitch and high commercial value without misalignment of reverse-feeding stitches with respect to normal-feeding stitches. .

In the above embodiment, the i1-node cylinder 4 is directly fixed to the output shaft 22a of the feed pulse motor 22, but it may be connected via an appropriate cam body and link mechanism.

[Brief explanation of the drawings] Fig. 1 is a perspective view of the exterior and interior of the sewing machine, Fig. 2 is a block diagram of the electric circuit, Fig. 8 is an explanatory diagram showing the relationship between the regulator and the cloth feed of the feed dog. FIG. 4 is a flowchart of the main part. Name of agent, Patent attorney Nagoya - Yu

Claims (1)

[Claims] It is possible to sew a predetermined pattern by controlling drive means individually related to image information based on needle swing information and cloth feed information corresponding to a plurality of different stitch patterns stored in a storage device. In a sewing machine with a needle bar, the needle bar protrudes upward from the top of the bed in synchronization with the vertical movement of the needle bar so as to transfer the fabric in one direction or the opposite direction, and moves parallel to the top of the bed in one direction or the opposite direction. A feed dog that can be moved in the same direction or in one direction while sinking downward from the top surface, and a position signal can be generated during the period when the feed bacteria are sinking downward from the top surface of the bed. A stepping motor that can be rotated in both forward and reverse directions using a position detector and electricity, and a stepping motor that is rotatably supported on the machine frame in relation to the stepping motor, and that feeds the cloth using a feed dog in accordance with the rotational position. A regulator that is linked to the feed dog to change the direction and feed pitch, a back stitch switch that can generate back signals in connection with manual operation, and a stepping motor that can generate back signals and position signals. During the first position signal generation M after pressing the back signal button, the cloth feed pitch is set to zero, and during the next position signal generation period, the cloth feed direction is reversed. Cloth feed control device L0 of a sewing machine equipped with a control circuit that operates as follows.