JPH0135720Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a pattern generation mechanism in a zigzag sewing machine, and in particular, it is attached to a pattern camshaft that is linked to a drive shaft, and each rotates at a different reduction ratio. The present invention relates to an engagement mechanism for a plurality of followers that follow the first and second pattern cams.

(Prior art) In conventional zigzag sewing machines, the approximate size of the sewing machine casing is determined, so the space inside the sewing machine casing is limited, and therefore the cam for pattern generation is either replaceable or Even with the built-in type, the size of the cam, especially the diameter, is limited, and the design must take into account the cam lift and presser angle so that the cam follower can swing. The number of times the rotating needle bar is oscillated is naturally limited, and the number of stitches in one pattern cycle cannot be increased freely, and most of the machines that have been put into practical use have a maximum reduction ratio of 1/18. was.

(Problem that the invention aims to solve) In recent years, it has been desired to make patterns such as satin and scallops larger, so a 1/36 reduction cam is partially incorporated to reduce the size of patterns such as satin and scallops. I wanted to create a 36-needle pattern, but as mentioned above, the cam lift corresponding to the pressure of the cam follower was limited, making it difficult to swing the needles over the full width of the zigzag sewing machine (for example, 7 mm). There were also restrictions on the pattern of climbing. In contrast, the purpose of the present invention is to obtain a large pattern by making the needle oscillate over the entire width even when the reduction ratio is 1/36.

(Means for solving the problem) In this invention, the first
A first patterned cam that is capable of rotating a second patterned cam coaxially with the patterned cam and supported via another transmission means at a different reduction ratio, and that is engageable with the first patterned cam and the second patterned cam. cam follower and a second cam follower that engages only with the second pattern cam, the first cam follower and the second cam follower are engaged with each other by operating an external dial to create the pattern. 1/36 by combining
A pattern using the full amplitude is obtained with a reduction ratio of .

(Example) An example of the present invention will be described in detail with reference to the drawings.
In Fig. 1, 1 is a sewing machine frame, 2 and 3 are mechanism frames that are fixed inside the sewing machine frame and stand upright in parallel in the front and back, and 4 and 5 are fixed to the mechanism frame, respectively. A parallel fixed shaft 6 is a selection shaft rotatably supported by the mechanism frame 2. 7 is a drive shaft rotatably supported on the sewing machine frame 1; a worm 8 is fixed to the drive shaft 7; and a worm gear 9 in which the worm 8 is rotatably supported on the fixed shaft 4. It meshes with the A first pattern cam 10 is rotated by the drive shaft at a reduction ratio of 1/18, is rotatably supported on the fixed shaft 4, and integrally transmits rotation through the pin 9a of the worm gear 9. has been done. The boss portion 10a of the first pattern cam 10 has a second reduction ratio of 1/36.
A pattern cam 11 is fitted.

Reference numeral 12 denotes a transmission gear, which is attached to the mechanism frame 3, and has a small gear part 1 integrated with the large gear part 12a.
2b and are rotatably held by a mounting portion 12c. The large gear portion 12a meshes with the tooth portion 10b of the first pattern cam 10, and the small gear portion 12b meshes with the tooth portion 11a of the second pattern cam 11, thereby controlling the rotation of the first pattern cam 10. It is further decelerated and transmitted to the second pattern cam 11.

Reference numeral 13 denotes a pattern selection operation section, which is fixed to the selection shaft 6. A feed release cam 14 having a gear portion 14a is fixed to the selection shaft 6, and a follower release cam 16 whose rotation is transmitted by a fixed pin 15 is fixed to the tip of the selection shaft 6. .

Reference numeral 17 designates a pattern cam selection cam, which is rotatably pivoted to a shaft portion 18 fixed to the mechanism frame 2, and whose teeth portion 17a corresponds to the tooth portion 14a of the feed release cam 14.
It meshes with.

The fixed shaft 5 has a swinging arm 19 and a first follower 2.
0, a second follower 21, a follower spring 22, and a swing opening arm 23 are respectively attached. The swinging arm 19
The groove of the first follower 20 is engaged with the protrusion 20b of the first follower 20, and the movement of the first follower 20 that engages with the first pattern cam 10 and the second pattern cam 11 is controlled by the groove. The force is transmitted to the swing arm 19, and the arm portion 19a of the swing arm 19 engages with a swing rod (none of which is shown) connected to the needle bar support that swings the needle. .

The second follower 21 includes the follower spring 22 and a slide stopper 19 provided on the swinging arm 19.
The axial position is limited by c and further positioned by the boss end 20a of the first follower 20. The rotation direction is biased by the action of a spring 24 in a counterclockwise direction and follows the second pattern cam 11. Reference numeral 25 denotes a swing claw slide plate, which is pivotably mounted on the selection shaft 6, and is biased by a spring 27 so that the claw portion 25b engages with the cam portion 17b of the selection cam 17. , the forked portion 25a is the first follower 20
The position of the first follower 20 is thereby controlled by the selection cam 17. The swing width release arm 23 is biased counterclockwise by a spring 26, and its claw portion 23a engages with the follower release cam 16.

Next, the operation will be explained. The drive shaft 7 rotates in the direction of arrow A in FIG.
The first pattern cam 10 is rotated in the direction of arrow B at a reduction ratio of 1/18. The first pattern cam 10
In contrast, the position of the first follower 20 is set as follows. By rotating the selection dial 13 fixed to the selection shaft 6, the follower release cam 16 fixed to the selection shaft 6 rotates, and the oscillating width release arm 23 locked thereto is rotated in the direction of the arrow C. When the screw tip 23b fixed to the bent portion comes into contact with the swinging arm 19, the swinging arm 19 is rotated clockwise. Similarly, when the follower 20 disengages from the first pattern cam 10, the lower surface 1 of the swinging arm 19
9d (FIG. 3), said second follower 21 engages with
also disengages from the second pattern cam 11. On the other hand, as the selection shaft 6 rotates, the fixed feed release cam 14 also rotates, and the selection cam 17 that engages with its teeth 14a rotates, causing the swinging claw slide plate 25 to come into contact with the cam surface 17b. The first follower 20 is moved in the axial direction by the forked portion 25a.
to move. This series of operations is performed by the follower release cam 16 and the selection cam 17, for each cam of the first pattern cam 10, opening of the first and second followers→movement of the first follower→ The first follower and the second follower are sequentially engaged.

When the first follower 20 is set to the position R in FIG. 2 by operating the selection dial 13, it is engaged with the first pattern cam 10c and is driven at a reduction ratio of 1/18. Convex portion 20b of follower 20 of No. 1
The signal is transmitted through the groove 19b of the swinging arm 19 that engages with the swinging rod to move the swinging rod to draw a normal pattern with a reduction ratio of 1/18 as shown in FIG. At this time, the second
The follower 21 is biased by the spring 22 and positioned in contact with the protrusion 19c of the swinging arm 19, and the second follower 21 is rotated at a speed of 1/36 by the spring 24.
However, as shown in FIG. 3, regardless of the positions of the first follower and the second follower, the swinging arm 19 maintains a clearance shown by α, and the second follower The movement of the follower is not transmitted in this part.

Next, when the first follower 20 is set to the position S in FIG. 4 by operating the selection dial 13,
The second follower 21 is positioned by the boss end 20a of the first follower 20, is removed from the second pattern cam 11, and the first follower 21 rotates at a reduced speed of 1/36. By engaging with the cam 11c of the second pattern cam 11, pattern stitching as shown in 2 in FIG. 5 is performed.

Next, when the first follower 20 is set to the position T in FIG. 2 by rotating the selection dial 13, it is engaged with the cam 10d of the first pattern cam 10, and the second follower The child 21 comes into contact with the boss portion of the first follower and engages with the second pattern cam 11c. A screw is fixed to the bent portion 20c of the first follower 20, and the tip 20d of the screw is located on the back side of the second follower 21 as shown in FIG.

In this case, the first pattern cam 10d has a reduction ratio of 1/
The stitch locus obtained by this cam is 1, 2, 3, . . . 18, as shown in FIG. The second pattern cam 11c engaged with the second follower 21 rotates at a reduction ratio of 1/36, and the stitch locus obtained by this cam is 1, 2, 3, . . . as shown in FIG. It is a satin pattern (three-moon pattern) with a number of 36.

Here, the L (left) side of the needle drop is the first pattern cam 10.
d, the mountain side of the second pattern cam 11c and the R (right) side are the valley sides of the first pattern cam 10d and the second pattern cam 11c, and the first follower 20 is connected to the second pattern cam 11c.
In the position shown in FIG.
The second pattern cam 11 engages the cam 11c of the second pattern cam 11 with the movement of the cam 10d of 0 toward the valley side.
The stitches are limited by the follower 21 of the stitches 21, resulting in a composite stitch as shown in FIG. The seam thus obtained is a seam with an enlarged width that can be obtained with a cam having a reduction ratio of 1/36 as shown in 2 in FIG. Note that by moving the first follower 20, the first follower becomes the first pattern cam 10e, and the second follower 21 becomes the first follower 21.
It is also possible to create other patterns with a reduction ratio of 1/36 by using the second pattern cam 11d. The reason why the engaging portions of the first follower 20 and the second follower 21 are screwed is to adjust their engagement state.

(Effects) With the above configuration, according to the present invention, by operating the selection dial, it is possible to select a stitch pattern with a conventional small reduction ratio and a stitch pattern with a different large reduction ratio. A stitch pattern is obtained by combining two stitch patterns with different values, and this composite pattern limits the cam lift in a stitch pattern with a larger reduction ratio than the conventional one, as in the embodiment. A seam with an expanded width can be obtained without being affected.

[Brief explanation of the drawing]

The drawings relate to an embodiment of the present invention, and FIG. 1 is a perspective view of the mechanism, FIG. 2 is an explanatory diagram of the cam follower engagement state, FIG. 3 is a side view thereof, and FIG. 4 is another cam follower engagement state. Fig. 5 is a pattern stitch locus, 7 is a drive shaft, 10 is a first pattern cam, 20 is a first cam follower, 11 is a second pattern cam, and 13 is a selection operation. 21 is a second cam follower.

Claims (1)

[Claims for Utility Model Registration] 1. A drive shaft that is rotatably supported within the sewing machine frame, and a cam follower that has one end removably supported on the outer periphery of a pattern cam that is linked to the rotation of the drive shaft. ,
In a sewing machine equipped with a needle bar support member which is caused to swing in a width direction via a connecting rod when one end of the cam follower is engaged with the pattern cam, the needle bar support member is caused to rotate at a reduced speed in conjunction with the rotation of the drive shaft. A first pattern cam and a second pattern cam having a different reduction ratio from the first pattern cam are mounted coaxially with the first pattern cam, and a first pattern cam having a different reduction ratio is installed by operating a pattern selection operation section. pattern cam and second
a first cam follower that is engaged with and disengaged from each of the pattern cams, and a second cam follower that is engaged with and disengaged from only the second pattern cam; A zigzag generating mechanism characterized in that the first cam follower is provided with an engaging portion for engaging with the child. 2. The zigzag generating mechanism according to claim 1, wherein the engaging portion of the first cam follower is a tip of a screw fixed to a bent portion of the first cam follower. .