JPH0479981A - Sewing machine for zigzag chain stitch - Google Patents

Abstract

PURPOSE:To make it possible for anyone to easily and promptly change the form of a zigzag chain stich by providing on both sides of a needle swing drive cam grooves for forming zigzag chain stitches of different types, and connecting either of the cam grooves to a needle oscillating means using a switching means. CONSTITUTION:When a projecting bar 10b is advanced by control of the dial 10a of a switching means 10, the switching means 10 shifts a pin support body 5a to the right and engages a first pin 6A in one cam groove R2 of a needle swing drive cam C. When the projecting bar 10b is retreated by control of the dial 10a of the switching means 10 the pin support body 5a is shifted to the left by the pressing force of a spring body 8. Thereby the first pin 6a is separated from the needle swing drive cam C and also a second pin 6b is engaged in the other cam groove R4 of the needle swing drive cam C. Under these conditions the sewing machine is driven and then a needle oscillating means oscillates along the cam groove R4 of the needle swing drive cam C and a four-point zigzag chain seam can be formed correspondingly to the cam groove R4.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a zigzag stitch sewing machine, and more particularly to a zigzag stitch sewing machine that can form two types of zigzag stitch patterns.

[Prior Art] A sewing needle that is driven for sewing is oscillated in the horizontal direction to form zigzag stitches such as the two-point zigzag stitch shown in FIG. 4(a) and the four-point zigzag stitch shown in FIG. 4(b). The zigzag stitch sewing machine is constructed as shown in FIGS. 5 to 8.

FIG. 5 is a diagram showing a zigzag stitch sewing machine. In the figure, 2 is an upper shaft and 3 is a lower shaft. Both shafts 2.3 are connected by a belt B so that they rotate together.

Further, l is a cam shaft (rotating shaft) supported by the body of the zigzag stitch sewing machine, and is provided on the lower shaft 3 via a worm body W1, and the rotation of the lower shaft 3 causes the needle swing drive cam C to rotate. The oscillating wheel W2 and the oscillating cam C are rotatably fitted with play.

The needle swing driving cam C shown in the figure is provided with a cam groove for a two-point zigzag stitch 1 on the front side, as an example.

The needle oscillating drive cam C is loosely fitted in the center to the cam shaft 1 and rotates together with the worm wheel W2, and is a needle oscillating drive cam when the reduction ratio is 1/6 for forming a two-point zigzag stitch. is a constant wave height Ra as shown in Figure 6.
It has an annular wave-shaped cam groove R2, and 0 to 6 indicate the needle swings of O to 6 shown in FIG. 4(a), forming one cycle.

Note that the radii r1 and r2 in the figure have a relationship of rl<r2.

On the other hand, A is a needle swinging means, and this needle swinging means A is 1
Width changing link L1, needle swing drive link L2, needle swing rod L3 (hereinafter referred to as link rod L1.L2L3), fixed pin P1 connecting these link rods, support pin P2,
A pin body P that engages with a cam groove R2 of a swing drive cam C is provided at the tip of the link rod L3.

Next, the action on the needle swinging means will be explained with reference to FIG.

When the needle swing drive cam C rotates, the pin body P engaged with the cam groove R2 swings up and down along the cam groove R2.

Due to this swinging, the needle swinging means A having the above-mentioned structure swings as shown in the solid line position and the dotted line position, and swings the tip of the link rod L2 in the horizontal direction by the wave height Ra of the cam groove R2. The needle oscillates by ra minutes (needle swing width).

Then, the arm portion of the needle bar support base N2 horizontally swings the needle bar N provided on the vertically movable iw shown in FIG. Let's do it, 4th
A two-point staggered seam as shown in Figure (a) can be formed.

Note that N3 is a needle bar holder that moves the sewing needle up and down in conjunction with the upper shaft of the sewing machine, and the fixing pin P1 of link Ll is a swing width adjustment arm that is provided on the body of the sewing machine via a swing width adjustment arm (not shown). It is connected to a knob, and the swing width can be changed by moving a fixed pin P1.

Next, make a 4-point zigzag stitch according to Figure 8 (see Figure 4 (b)).
The needle oscillating drive cam C, which forms the following, will be explained.

This needle swing drive cam C moves the needle at four points (fourth point) in one rotation.
The points corresponding to O to 6 shown in FIG.
The sewing needle is oscillated by the needle oscillating means A described above, as shown in the same figure (b).
As shown in the figure, a four-point staggered seam is formed.

Note that the radii r3, r4, r5, and r6 in the figure are r3<r
The relationship is 4<r5<r6.

As explained above, the zigzag stitch sewing machine is operated by replacing the needle oscillating drive cam C.

[Problems to be Solved by the Invention] However, the above conventional technology has the following problems.

be.

When replacing the needle oscillation drive cam, remove the needle position change base mounting plate 4 of the zigzag stitch sewing machine shown in Fig. 5, and then replace and adjust the needle oscillation drive cam C, which requires specialized knowledge. Such complicated work requires a lot of time and is difficult for sewing manufacturers who generally use sewing machines, so it is recommended that specialized technicians be carried out. This is a factor that significantly reduces sewing work efficiency.

[Means for Solving the Problems] This invention has been made to solve the above-mentioned conventional problems, and is based on a zigzag stitch sewing machine that rotates around a fixed shaft that is linked to the main shaft of the sewing machine and supported by the machine frame. The oscillating drive cam rotates and has annular cam grooves formed in different zigzag patterns on both sides thereof, and holds first and second pin bodies that respectively oppose both cams of the oscillating drive cam. a holding arm, a switching means for moving the holding arm in the axial direction of the fixed shaft so that either the first or second pin body of the holding arm is engaged with the cam groove of the needle swing drive cam; Needle swing means is provided between the arm and the needle bar and transmits the swing of the holding arm that swings along the cam groove by rotation of the needle swing drive cam to the sewing needle. This is an attempt to solve conventional problems.

[Function] In the zigzag stitch sewing machine according to the present invention, the holding arm is moved by the switching means, and either the first pin body or the second pin body is engaged with one of the cam grooves of the needle swing drive cam. ξ.

As a result, the holding arm swings along the cam groove due to the rotation of the needle swing drive cam, and the needle swing means transmits the swinging motion of the holding arm to the needle bar to form a predetermined zigzag stitch. Swing the needle bar horizontally.

[Embodiments of the invention] The present invention will be described in detail based on the drawings.

The same parts as in the traffic example are given the same reference numerals and repeated explanations will be omitted.

1 to 3 are diagrams showing one embodiment of the present invention.

In FIG. 1, C is a needle oscillating drive cam, which is equipped with a cam groove R2 forming a two-point zigzag stitch in all directions.
The other side has a cam groove R4 forming a four-point staggered seam, and is loosely fitted to the fixed shaft l together with the worm wheel w2.

Reference numeral 5 denotes a holding arm, and this holding arm 5 includes a first pin 6a and a second pin 6b facing both cam grooves R2 and R4 of the needle swinging drive cam C, and a link rod of the needle swinging means. It consists of a pin support 5a provided on L3 so as to be slidable in the axial direction of the fixed shaft 1 by means of a horizontal bar 5al, and a slide body 5b that supports the pin support 5a so as to be slidable in the vertical direction.

As shown in FIG. 2, the slide body 5b supports the pin support body 5a in the vertical direction through a slide groove S, and has its lower end slidably connected to the fixed shaft l.

Reference numeral 8 denotes a spring body, which has one end in contact with the link rod L3 and the other end in contact with the pin support 5a, urging the pin support 5a leftward in the figure.

On the other hand, 10 is a switching means, which is the machine frame (body) of the sewing machine.
The movement rod 10b has a screw 10bl, and by rotating the dial 10a, it can be rotated in the axial direction of the fixed shaft 1. It is designed to advance and retreat.

(The figure shows the time of advance) In addition to the above-mentioned screw type, a bush type or the like may be used.

FIG. 3 is a diagram showing the installation position of the dial 10a of this switching means 10 in a zigzag stitch sewing machine, and is located at a location that is easy for the operator to operate.

Next, the operation of the zigzag stitch sewing machine having the above configuration will be explained.

Operate the dial 10a of the compliment means 10, and move the advance/retreat rod 1.
When 0b is advanced, the switching means 10 switches the pin support 5
a to the right in the figure, and the first pin 6a is engaged with one cam groove R2 of the oscillating drive cam C. (1st
(state shown in the figure) When the sewing machine is driven in this state, the needle swinging means swings along one cam groove R2 of the needle swing drive cam C, and performs a two-point zigzag stitch according to this cam groove R2. can be formed.

Further, when the dial 10a of the switching means 10 is operated to move the advance/retreat rod 10b backward, the pin support 5a is moved to the left in the figure by the biasing force of the spring body 8.

As a result, the first pin 6a separates from the oscillating drive cam C, and the second pin 6b engages with the other cam groove R4 of the oscillating drive cam C.

When the sewing machine is driven in this state, the needle swinging means swings along the other cam groove R4 of the needle swing drive cam C, and a four-point zigzag stitch can be formed according to this cam groove R4. .

As explained above, the zigzag stitch sewing machine according to the present invention can easily and quickly switch between two types of zigzag stitches in one operation by operating the switching means 10.

Further, in the above embodiment, the rotation of the needle oscillation drive cam C is taken from the lower shaft 3, but the same effect can be obtained even if the rotation of the needle oscillation drive cam is taken from the upper shaft.

[Effects of the Invention] As explained above, the zigzag stitch sewing machine according to the present invention has cam grooves forming different zigzag stitches on both sides of the needle oscillation drive cam, and the zigzag stitch sewing machine according to the present invention has cam grooves forming different zigzag stitches on both sides of the needle oscillation drive cam. Since either of these can be connected to the needle swinging means, anyone can easily and quickly change the shape of the zigzag stitch by operating the switching means, improving sewing work efficiency. I can do it.

[Brief explanation of drawings]

1 and 3 are diagrams showing an embodiment of the zigzag stitch sewing machine according to the present invention, and FIG. 1 shows the configuration of the fixed shaft, needle swing drive cam, holding arm, switching means, etc. of the sewing machine. 2 is a front view of FIG. 1 showing the installed state of the sliding body of the holding arm; FIG. 3 is an external perspective view showing the installation position of the switching means in the zigzag sewing machine; Figure 4 is a diagram showing a zigzag seam; figure (a) is an explanatory diagram showing a two-point zigzag seam;
) is an explanatory diagram showing a 4-point staggered seam, Figures 5 and 8.
The figure shows a conventional technique. Figure 5 is a partially cutaway perspective view showing the configuration of the upper shaft, lower shaft, needle swing drive cam, etc. of a zigzag sewing machine. Figure 6 is a two-point zigzag sewing machine. An explanatory diagram showing the needle swinging drive cam that forms the stitches and the needle swinging means, FIG. 7 is a diagram showing the needle swinging means, and FIG. 7(a) is a diagram showing the action of the needle swinging means. , same figure (b)
FIG. 8 is a perspective view showing the needle bar etc. that are swung by the needle oscillating means, and FIG. 8 is a diagram showing a needle oscillating drive cam that forms a four-point zigzag stitch. In the figure, 1...Fixed shaft 5...Holding arm 10...Switching means A...Needle swinging means C...Needle swinging drive cam 6a...First pin body 6b...Second pin body

Claims (1)

[Scope of Claims] A zigzag stitch sewing machine capable of forming zigzag horizontal stitches by horizontally swinging a needle bar having sewing needles that drive the sewing machine, the sewing machine being able to form zigzag horizontal stitches in conjunction with the main shaft of the sewing machine. a needle swing drive cam that rotates around a supported fixed shaft and has annular cam grooves formed in different staggered horizontal patterns on both sides;
, a holding arm that holds the second pin body, and the holding arm is moved in the axial direction of the fixed shaft so that either the first or second pin body of this holding arm is engaged with the cam groove of the needle swing drive cam. and a needle swinging means that is provided between the holding arm and the sewing needle and transmits the swinging motion of the holding arm, which swings along the cam groove by the rotation of the needle swinging drive cam, to the needle bar. A zigzag stitch sewing machine characterized by comprising: and.