JPS61199885A - Control apparatus of zigzag 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 [Field of Industrial Application] The present invention relates to a control device for a zigzag sewing machine having a pattern stitching function, and more particularly to a control device for prohibiting pattern stitch mode selection in the bobbin winding state.

[Conventional technology]

In conventional zigzag sewing machines of this type, the needle bar is generally in the upper position (i.e., between 30 and 60 from its top dead center).
Many of them are equipped with a needle position detector that outputs a high (H) level when the needle is in the upper position, and a low (L) level when the needle is in a position other than the above-mentioned upper position (not shown because it is well known)
, in these sewing machines, when the needle bar is not in the upper position,
In other words, when the L level output is selected, the sewing machine rotates at low speed when the pattern stitching mode is selected, and stops when the needle position signal becomes H level.In other words, the sewing machine automatically stops when the pattern stitching mode is selected. It was configured.

[Problem that the invention seeks to solve]

However, in this type of sewing machine, especially in this type of home-use sewing machine, when winding the bobbin for bobbin, when the bobbin shaft is moved to the operating position, the bobbin winding switch is turned on and at the same time the main motor (sewing machine motor) drive system is turned on. Main shaft (
The bobbin winding shaft link moves to disconnect from the bobbin winding shaft (upper shaft), and as the main motor rotates, the coupling engagement of the clutch is released at the upper position of the needle bar, the main shaft stops, and the bobbin winding shaft rotates to unwind the bobbin. In this way, when the bobbin winding shaft is in the operating position and the connection between the main shaft and the main motor drive system is disconnected, If the pattern sewing mode is selected, the main motor starts rotating so as to automatically stop the needle bar in the upper position, but since the main shaft does not rotate, the upper position signal is not generated by the needle position detector. The main motor had the disadvantage of continuing to rotate forever.

The present invention has been made in view of the problems of the prior art as described above, and is designed to automatically stop the spool when the pattern sewing mode is selected when the needle bar is not in the upper position. The purpose of the present invention is to provide a control device that prohibits selection of pattern stitching mode.

[Means for solving problems]

For this reason, the present invention is configured so that the operation signal of the pattern stitch mode selection switch is not transmitted to the pattern stitch control microcomputer during thread winding.

〔Example〕

The present invention will be explained below based on drawings of embodiments. FIG. 1 shows a circuit diagram of an embodiment according to the present invention, P is a pattern sewing mode selection switch, Sw, Sw2, . . .
. . , SW7 is a selection switch for each pattern, and is a so-called momentary type switch that closes only when pressed and opens when one hand is released. 1 is an encoder consisting of an IC, and when the enable terminal E is at low (L) level, the inputs D, , D2, . . .
・When an L level signal is input to the input terminal in -07, the 3-bit binary number corresponding to that input is output to the output terminals YA and Y.
0 appearing in B, YC For example, selection switch SW3 is O
When it is N, the input D3 becomes L level and the output (Yc.

Similarly, when the selection switch SW6 is turned on,
Similarly, the outputs (YC, YB, YA) are respectively (L,
L, H) level. 2 is a microcomputer,
By reading the change in the output of the encoder 1 and recognizing that the pattern has been selected, a rotation command signal S and a low speed command signal SL are output to the main motor control circuit 3 of the main motor M, and the main motor drive circuit Through 4,
The sewing machine is rotated, and the needle bar of the sewing machine is stopped in the upper position based on the needle position signal from the needle position detector 5.

The needle position detector 5 is a known photodetector that uses one light emitting diode and a phototransistor to detect through a slit provided in a detection disk that rotates together with the main shaft, and detects whether light passes through the slit. In this embodiment, the high (H) level is detected when the needle bar is in the upper position (approximately 30 to 60 degrees from the top dead center). At other phase angles, a low (L) level output signal is output to the microcomputer 2.

Also, 6 is a bobbin winding switch, which is used to detect whether the bobbin winding lever is in the operating position.

It turns ON when it is at the bobbin winding position. 7 is an inverter for stabilizing the output voltage.

The main motor control circuit 3 sends a signal to the drive circuit 4 to rotate the main motor M when the rotation command signal S from the microcomputer 2 is input at H level, and to stop the main motor M when input at L level. Additionally, if the low speed signal SL is input to H level while the rotation command signal S is being output at H level, the sewing machine will rotate at low speed regardless of the setting position of the speed adjustment slide volume (not shown) attached to the sewing machine frame. . In addition, by inputting the low speed signal sL at the L level, the main motor drive circuit 4 causes the main motor M to rotate at the speed set by the slide volume.
outputs a drive control signal.

Next, the operation will be explained using the flowchart shown in FIG. Other than when winding the thread, the pattern selection switch SW3 is currently set to O.
N, the output of encoder 1 (Yc, YB
, YA) respectively from the level (H, H, H) to (
H, I, , L), so the answer in step 1 is Yes, and the process advances to the next step 2. Next, if the needle (bar) position signal is in the upper position, the answer is Yes, and the microcomputer 2 proceeds to the next flow (not shown) without controlling the main motor M. If there is, the rotation command signal S is set to H level and the low speed command signal Sl is set to H level.
Rotate the sewing machine by outputting to the level. Next, in step 3, if the needle position signal is L and bell,
It circulates in the loop until the H level signal is input, and when the sewing machine rotates and the needle position signal reaches H level, it outputs the rotation command signal S at L level, stops the rotation of the sewing machine, and moves the needle to the upper position. to stop it.

Here, during the bobbin winding, the bobbin winding switch 6
turns on, the enable terminal E of encoder 1 is set to H.
level, and any of the pattern stitching mode selection switches P is turned on during thread winding.

Encoder 1 does not accept this and outputs (Yc.

Since row 5) remains at the (H, H, H) level and does not change, the operation of the microcomputer 2 does not change at all as described above, so the pattern selection is not changed and the main motor M remains stopped. It is.

In the above embodiment, the pattern mode selection signal is not transmitted from the encoder 1 to the control microcomputer 2 by the thread winding switch signal.
Of course, the same effect can be obtained by inputting both the selection signal and the winding switch signal directly to the microcomputer terminal and constructing logic to achieve the same purpose using the microcomputer's software.

,〔Effect of the invention〕 As explained above, according to the present invention.

In a sewing machine where the needle bar automatically stops when the pattern sewing mode is selected, selection of the pattern sewing mode is prohibited while winding the thread, which avoids the disadvantage of the main motor continuing to rotate as in conventional models. It has become possible to maximize the advantage of the above-mentioned automatic top stop, which is important in terms of sewing work efficiency.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of an embodiment according to the present invention, and FIG. 2 is a circuit diagram of an embodiment according to the present invention.
This is an operation flowchart. 1... Encoder 2... Microcomputer 3... Main motor control circuit 4... Main motor drive circuit 5... Needle position detector 6...Bottom winding switch M...Main motor (sewing machine motor) P...
...Pattern sewing mode selection switch Applicant: Tokyo Heavy Equipment Industry Co., Ltd. Figure 1

Claims (1)

[Claims] A zigzag sewing machine configured to automatically stop in the upper position when a pattern sewing mode is selected when the needle bar is not in the upper position, characterized in that a control means is provided for disabling the selection of the pattern sewing mode during a bobbin winding operation. Zigzag sewing machine control device.