JPS607667Y2 - Sewing machine control device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to improvements in reverse stitching operations and low speed sewing in sewing machines.

Conventional sewing machines of this type are equipped with separate switches for reverse stitching and low speed stitching, and each switch is manually operated to perform a predetermined operation. For the convenience of manual operation of the two switches, the two switches on the sewing machine arm are mounted side by side at the same position, so that the operator often operates them by mistake.

Moreover, not only does it require space to mount two switches, but it is also disadvantageous from a cost perspective.

This invention was developed with this point in mind, and is intended to allow the sewing machine to perform reverse stitching and low speed sewing with a single switch.

That is, if the foot pedal is operated and a single switch is operated while the sewing machine is in sewing operation, the reverse stitch mechanism of the sewing machine is operated, and when the foot pedal is released and the sewing machine is stopped, the same single switch is operated. The purpose of this operation is to perform low-speed sewing.

An embodiment of this invention will be described below with reference to FIGS. 1 and 2.

First, in FIG. 1, 1 is a first switch that is closed in conjunction with the operation of a foot pedal (not shown) of the sewing machine;
2 is a second switch that commands reverse stitching or low speed stitching; 3 and 4 are fixed resistors.

5, 6, and 8 are logical NOT circuits, and 7 and 9 are AND circuits, and these circuits form a drive signal generation circuit.

10 is a sewing machine drive circuit that drives the sewing machine when the potential at point ■ is logic "1", 11 is a reverse stitch drive circuit that operates the reverse stitch mechanism of the sewing machine when the potential at point [F] is logic 44199, and 12 is a logic circuit where the potential at point 0 is logic. This is a low-speed sewing drive circuit for causing the sewing machine to sew at a low speed when the speed is 1.

FIG. 2 is a timing chart for explaining the operating state of FIG. 1.

Next, the operation will be explained.

When the first switch 1 is closed at point ■ in FIG. A sewing machine (not shown) performs sewing operation.

When the second switch 2 is closed while maintaining this state (point @ in Figure 2), the 0 direct weight position becomes logic "0", and the output of the logic negation circuit 6, that is, the potential at the 0 point becomes logic "1". Become.

Since the input ■ and the 0 direct weight position of the AND circuit 7 both become logic "1", its output, that is, the potential at point [F] becomes logic "1", and the reverse stitch drive circuit 11 operates to operate the reverse stitch mechanism of the sewing machine. Activate.

To summarize the above explanation, when the second switch 2 is closed during sewing operation of the sewing machine, a reverse stitching operation is performed.

Next, when the first switch 1 is opened, the straight load position becomes logic "1" by the fixed resistor 3, and the output of the logic negation circuit 5, that is, the straight load position becomes logic "0" and the sewing machine is driven. Circuit 10 becomes inactive, causing the sewing machine to stop sewing.

(corresponding to 0 point in Figure 2) While maintaining this state,
When switch 2 is closed (corresponds to point ■ in Figure 2)
The 0 direct weight position becomes the logic "1pa".

Also, since the input level of the AND circuit 7 is logic 44099, its output, that is, the potential at point [F] is logic "0", and the reverse stitch drive circuit 11 is inactive.

At this time, the output of the logic NOT circuit 8, that is, the potential at point [F] is the logic 441u.

Since the input of the AND circuit 9, that is, the potential at point 0 and point [F], both become logic ``1'', the output, ie, the 0 direct position becomes logic ``1'', and the low-speed sewing drive circuit 12 operates. The sewing machine will be operated at low speed.

As explained above, according to this invention, if the second switch 2 is closed while the sewing machine is sewing, reverse stitching can be performed, and if the same second switch 2 is closed while the sewing machine is stopped, Low speed sewing can be performed.

In other words, the two switches that were conventionally required for each operation can be combined into one, making it possible to prevent operational errors and eliminating the need for a large space for installing the switches. This also contributes to cost reduction.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of this invention, and FIG. 2 is a time chart for explaining the operation of FIG. 1. In the figure, 1 is a first switch, 2 is a second switch, 5.
6.8 is a logical NOT circuit, 7 and 9 are AND circuits, 10 is a sewing machine drive circuit, 11 is a reverse stitch drive circuit, and 12 is a low speed stitch drive circuit.

Claims (2)

[Scope of utility model registration request] (1) A first switch that is closed in conjunction with the operation of the foot pedal of the sewing machine, a second switch that is closed by manual operation, and a drive circuit for the sewing machine when only the first switch is closed. When only the second switch is closed, a drive signal is supplied to the low-speed sewing drive circuit of the sewing machine. When both the first and second switches are closed, a drive signal is supplied to the reverse stitch drive circuit of the sewing machine. a drive signal generation circuit that supplies
Sewing machine control device equipped with (2) The control device for a sewing machine according to claim 1, wherein the drive signal generation circuit comprises a plurality of AND circuits and a logic NOT circuit.