JPS6119277B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] The present invention relates to a method of attaching a sewing machine needle position detection device.

[Prior art]

A needle position detection device that detects the position of a sewing machine needle and stops it at a predetermined position generally consists of a rotating part that is directly connected to the upper shaft and rotates in synchronization with the sewing machine needle, and a ball bearing on this part. It consisted of a fixed part that was fixed in the direction and rotatably supported.

[Problems with conventional technology and their technical analysis]

Conventionally, the above-mentioned detection device was installed by adjusting the mounting angle between the rotating part of the detection device and the upper shaft, in order to stop the needle at a predetermined position near the bottom dead center or top dead center when the sewing machine finished sewing. Ta.

That is, this will be explained in detail with reference to FIGS. 1 and 2.
1 is the sewing machine arm, 2 is the upper shaft, 3 is the hand wheel, 4
5 is a mounting collar, and 5 is a needle position detection device having a rotating portion 5a. In addition, 4b, 4c, and 5b, 5c
are the mounting holes and mounting screw holes of the mounting collar 4 and rotating portion 5a to the upper shaft 2, respectively. The rotating portion 5a of the needle position detection device 5 is attached to the upper shaft 2 via the attachment collar 4 with screws 6 and 7, but the attachment adjustment is very troublesome and requires time and effort.
If the angle of attachment is incorrect, the needle, movable thread cutting blade, etc. may be damaged. An example of this mounting adjustment method that has been used in the past is as follows.

First, turn the upper shaft 2 and as shown in Figure 2,
The needle bar 12 is placed at a predetermined upper stop position of the needle 13 (the upper shaft rotation angle is approximately 60 degrees past the top dead center of the needle bar as 0 degrees).

Adjustment 2 can be made, for example, by adjusting the base line 1 made on the needle bar 12.
2a and the lower end surface of the needle bar metal 11 were confirmed.

Next, while maintaining this upper shaft rotational angular position, the detection device was fixed to the upper shaft in consideration of the sensor position within the detection device 5 corresponding to the needle up stop position.

For example, 5b in the mounting screw hole of the rotating part 5a.
is provided in line with the sensor function at a predetermined angular position in the detection device 5 in the axial direction.
As can be seen from the figure, the screw 6 used to adjust the combination of the mounting collar 4 and the rotating part 5a and set on the upper shaft must be tightened in the correct direction perpendicular to the horizontal plane. These adjustment and fixing operations were performed without blindly moving the upper shaft, and the fixing position was determined by the operator's intuition. Therefore, after assembly, it is necessary to confirm that the needle bar is operating properly, and its adjustment is cumbersome and has many unstable elements.

[Technical issues]

SUMMARY OF THE INVENTION An object of the present invention is to quickly and easily attach a needle position detecting device to the upper shaft of the needle position detecting device without erroneously fixing the device to the upper shaft.

[Technical means]

In the present invention, the above problem was solved by the following means. That is, at a predetermined position on the rear end surface of the handwheel on the upper shaft at the needle up stop position (generally, the handwheel in industrial sewing machines is restricted from rotating relative to each other by appropriate means at a predetermined position in the upper shaft axial direction). , a reference indicator is displayed or a part is formed, and the position of a predetermined sensor part of the needle position detecting device corresponding to the above-mentioned needle up stop position is displayed or a part is formed on the device mounting collar.

Then, the markings on the hand wheel side and the mounting collar side are made to match, or the respective forming portions are formed, and then the parts are fixed to the upper shaft.

[Effect of technical means]

Under the above means, it is obvious that the handwheel side and the mounting collar side match the display, or that the forming parts are engaged and installed, and that the rotation angle at the needle up stop position is on the upper axis of the rotation angle. , the desired position of the sensor of the needle position/stop detection device (rotating part) is properly positioned.

[Special effects produced by the present invention]

According to the means of the present invention, there is no need to align the upper stop position of the needle bar each time as seen in conventional adjustment examples, and the above-mentioned matching of each display or the operation of the forming part engagement can be performed quickly. It can be easily installed and achieves the intended purpose. Moreover, since the mounting angle is always exactly constant, there is no need for angle adjustment, and therefore the trouble of confirming proper operation each time it is mounted can be eliminated.

[Example] An example of the present invention will be described with reference to FIG.
(Parts that are the same or have the same function as those in Fig. 1 are given the same numbers.) 1 is a sewing machine arm, 2 is an upper shaft, 3 is a handwheel that rotates in synchronization with the upper shaft 2, and the rear end of the handwheel 3 is A groove portion 3a is provided. Reference numeral 4 denotes a mounting collar, and one end thereof has a protrusion 4a that engages with the groove 3a of the hand wheel.
has. Reference numerals 4b and 4c are mounting holes to be described later. 5 is a needle position detection device, and 5a is a rotating portion thereof supported by a bearing on the device. This rotating portion 5a is connected to a rotatable sensor member (not shown) within the detection device 5. 5d is a fixed part of the needle position detection device 5, and by engagement with the fixed rod 8,
Blind movement of the detection device in the circumferential direction is prevented.
The fixing rod 8 has one end inserted into the hole 1a of the sewing machine arm and is fixed with a screw 9, and 11 indicates a lead wire. The rotating part 5a of the detection device is fitted into the mounting collar 4, and the screw hole 5b,
5c, and is attached to the upper shaft with screws 6 and 7 through the attachment holes 4b and 4c. During this installation, the groove 3a of the hand wheel and the protrusion 4a of the mounting collar are placed so that they are engaged with each other, and the position breaking portion 5a of the protrusion 4a corresponds to a predetermined position of the sensor connected. This is as stated in the technical means section above.

In this embodiment, a groove 3a is provided on the hand wheel 3, and a protrusion 4a is provided on the mounting collar 4, but these means for engaging each part are eliminated, and display means are provided for each part, and these are aligned to position and fix. Needless to say, it is okay to do so.

[Brief explanation of the drawing]

Figures 1 and 2 are explanatory diagrams for installation and adjustment of conventional equipment;
The figure is an explanatory view of the configuration and installation of the device according to the present invention. 2...Upper shaft, 3...Hizumi wheel, 4...Mounting collar, 5
...Hand position detection device, 5a...Rotating part.

Claims (1)

[Claims] 1. A recognition means provided on the handwheel on the upper shaft that enables the needle top stop position to be known, and a sensor position of a needle position detection device that operates corresponding to the needle top stop position.
Attaching the sewing machine needle position detecting device in a predetermined relative position and fixing the needle position detecting device to the upper shaft by matching the needle position detecting device with the husband display means or by means of the part forming engagement means. Method.