JPS62112590A - Apparatus for detecting residual amount of bobbin thread 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] [Object of the Invention] (Industrial Application Field) The present invention relates to a bobbin thread remaining amount device for a sewing machine, and more particularly, to a means for completely shutting down the operation of the device. It is something.

(Prior art) Conventional bobbin thread remaining amount detection device, for example, Japanese Patent Publication No. 57-408
As shown in FIG. 6, when the bobbin thread remaining in the bobbin B inserted in the bobbin case A decreases, the thread detector C detects the pin CI. Due to the intervening yarn detection body 2D, it is displaced to the left (indicated by a dotted line) in the figure. In conjunction with this movement, the detected object E is similarly displaced to the left dotted line water position. Due to this displacement, the distance from the detector F becomes narrower, and the light emitted from the light emitting part F1 of the detector F is reflected on the detected object E, and then detected by the light receiving part F2 of the detector F. is activated to issue a warning of bobbin thread consumption.

(Problem to be Solved by the Invention) However, since the upper thread rotates at a reasonable speed around the outer periphery of the bobbin case that holds the bobbin, the thread may become stiff around the hook.
Dust from sewing items accumulates.

In this case, the detector near the bobbin may also be impaired in its ability to emit and receive light due to the bulge, and may not issue an alarm to that effect even if the bobbin thread is decreasing.

Therefore, the technical object of the present invention is to remove dust attached to a detector.

Structure of the invention C] (Means for solving the problem) The technical means taken to solve the above technical problem is to use a detector that optically detects the remaining amount of bobbin thread wound around the bobbin. The detector is installed on the underside of the throat plate so that when the throat plate is slid on the sewing machine bed, the detector is brushed away.

(Function) Since the needle plate is always slid when replacing the bobbin, dust adhering to the detector must be periodically wiped off, and the dust that accumulates can impair the operation of the detector. There's no way you'll be disappointed.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 5.

As is well known, the throat plate 12 that slides along the groove 11 formed on the surface of the bed 10 of the sewing machine moves through the opening 1 of the recess 13 formed over a relatively wide area above the bed 10.
Open and close 3a. Therefore, the thread 17 is contained in the inner hook 16 held in the horizontal rotary hook 15 disposed in the recess 13.
A bobbin 18 wound with is mounted.

The bobbin 18 is of the same type as those commercially available and includes two axially opposed flanges 18a and 18b. A plurality of holes 18c are bored in the flange 18a facing the lower surface of the throat plate 12 at a predetermined pitch in the circumferential direction. A diffused light type photocoupler 19 serving as a detector is attached to the lower surface of the needle plate 12, and faces the negative hole 18C of the bobbin 18. Thus, the detector 19 includes a light emitting section 19a and a light receiving section 19b.
It is connected to a control circuit 21 equipped with a buzzer 20.

From the light emitting part 19a of the detector 19 to the hole 18 of the bobbin 18
The light emitted towards c is reflected by the thread 17 and then received by the light receiving section 19b. At this time, the output of the detector 19 has little voltage fluctuation as shown in FIG.
1a, the control circuit 21 is not activated. However, even though the light is emitted from the light emitting part 19a of the detector 19, the light does not reach the light receiving part 19b, and the voltage fluctuation of the output of the detector 19 becomes large. The L-type pulse signal as shown in b) is transmitted to the control unit 2.
1b, this signal is converted by the display section 21G as shown in FIG. It has become.

A base body 22 is embedded in the stepped portion 10a located on the right side of the horizontal rotary pot 15, and a brush 23 is implanted in the tip portion 22a of the base body 22.

Therefore, the height of the tip of the brush 23 is higher than the lower surface of the detector 19.

To describe the operation of the above configuration, as the sewing machine is used, the bobbin thread 17 is consumed and when the winding amount reaches inside the hole 18C of the bobbin 18 as shown in the second figure, the control circuit 21 is activated. Then, a warning to that effect is emitted by the buzzer 20. At that point, you should replace the bobbin 18 (
When the throat plate 12 is moved to the right as seen in the diagram, the detector 19 passes through the brush 23 as shown in FIG. Dust attached to the portion 19b is wiped off.

〔Effect of the invention〕

In order to solve the above-mentioned technical problem, it may be possible to use air to remove the dust attached to the emitting and receiving parts of the detector, but this would require a vibrator that blows air to the detector. , the detector must be brought close to the detector only when the sewing machine is at rest, making the configuration complicated. In contrast, in the present invention, the detector is attached to the lower surface of the throat plate, and the detector is simply cleaned with a brush when replacing the bobbin or when moving the throat plate, so the configuration is extremely simple.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the bobbin thread remaining amount detection device according to the present invention, and FIG.
3 and 3 are explanatory diagrams of the operation of the first illustrated device, and FIG. 4 is a block diagram of a control system connected to the first illustrated device,
FIG. 5 is a signal waveform diagram, and FIG. 6 is an example diagram of a conventional bobbin thread remaining amount detection device. 10... Bed, 12... Throat plate, 17... 1 Ireshi Construction Line Company Representative Kiyoshi Ito 1 Figure 2 Figure 3 Meat Figure 4 Figure 5 Figure 6F! ! J

Claims (1)

[Claims] A detector for optically detecting the remaining amount of bobbin thread wound around the bobbin is provided on the lower surface of the throat plate, and the detector comes into contact with the brush when the throat plate is slid on the sewing machine bed. , a lower thread remaining amount detection device for sewing machines.