JPH0126368Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Branch Field) The present invention relates to a pattern cam drive mechanism in a zigzag sewing machine, and particularly relates to a reduction mechanism for a pattern cam shaft that is linked to a drive shaft.

(Purpose of the invention) The purpose of the invention is to incorporate a plurality of pattern cams with different reduction ratios in a narrow space within the sewing machine frame, and to change the length of the pattern in one cycle by operating a selection operation section provided externally. The purpose is to make it possible to easily select and sew various sewing patterns, and another purpose is to create a pattern that generates a multi-stitch sewing pattern with a relatively large number of stitches in one cycle in a narrow space within the sewing machine frame. Another purpose is to make the pattern cam mechanism compact by arranging a plurality of pattern cam groups having different reduction ratios on one axis.

(Prior art) In conventional zigzag sewing machines, the approximate size of the machine frame is fixed, so the space inside the machine frame is limited, and therefore the pattern generation cam is either replaceable or With the built-in type, the size of the cam, especially the diameter, is limited, and the cam lift must be designed so that the cam follower can swing, so the needle bar cannot be oscillated during one revolution of the pattern generating cam. Since the number of stitches to be sewn is naturally limited, the number of stitches in one pattern cycle cannot be freely increased, and therefore there has been an obstacle in designing the shape of the sewing pattern freely.

(Structure) The present invention was proposed to eliminate the above-mentioned conventional defects, and the specific structure is as follows.

1 to 3 show a first embodiment of the present invention, in which 1 is a sewing machine frame, 2 and 3 are front and rear mechanism frames fixed inside the sewing machine frame, and 4 and 5 are
6 is a parallel fixed shaft fixed to the mechanism frame, 6 is an amplitude adjustment shaft rotatably supported between the mechanism frames 2 and 3, and 7 is rotatably supported on the mechanism frame 2. This is the selected axis.

8 is a drive shaft rotatably supported on the sewing machine frame 1; a worm 9 is fixed to the drive shaft; It is meshed with a worm gear 11 that is integrated with the pattern cam 10.

Reference numeral 12 denotes a pattern selection operation section, which is fixed to the protrusion of the selection shaft 7 from the machine frame 1. When the operation section 12 is rotated, a gear 14 integrated with the angular division plate 13 fixed to the selection shaft 7 is activated. Rotated.

An intermediate gear 15 meshes with the gear 14 and is supported by the mechanism frame 2.

A rotatable gear 16 is prevented from moving in the axial direction by a fixed shaft 4 fixed to the mechanism frames 2 and 3, and is meshed with the intermediate gear 15, and a pattern cam selection cam 17 and a follower release cam 18. It is integrated. Reference numeral 19 denotes an amplitude adjustment operating section fixed to the protrusion outside the machine frame of the amplitude adjustment shaft 6, and 20 denotes a circumferential cam fixed to the amplitude adjustment shaft 6 for cutting and releasing the follower; An end cam 21 for moving the follower is integrally fixed to the cut/release cam.

Reference numerals 22 and 22a are release followers, and one follower 22 is fixed to the side surface of the vertically bent end portion of the follower sliding plate 23 rotatably supported by the fixed shaft 5.
3a, one end of which is engaged with the follower release cam 18, and the other release follower 22a is engaged with the swing width cut/release cam.
Reference numeral 24 denotes a follower support body supported on the fixed shaft 5 so as to be able to slide in the axial direction, and plates of cam followers 25, 25 are fixed to both sides of the support body. A sliding protrusion 26 protrudes at a suitable position on the plate of the follower,
26 is fitted in a sliding groove 27 parallel to the fixed shaft 5 formed on the follower sliding plate 23, so that the cam followers 25, 25 are fitted in the fixed shaft 5 along the sliding groove 27. It is movable in the longitudinal direction and is supported so as to be swingable about the fixed shaft 5 together with the sliding plate 23, and one end is connected to the first pattern cam 10 and the second pattern cam. cam 28
It is arranged so that it can be sequentially engaged and detached.

The follower support body 24 is integrally provided with engaging protrusions 31 and 31 having ends 29 and 30 parallel to the axial direction of the fixed shaft 5, and the ends 29 and 30 are respectively It is engaged with the side cam portion of the pattern cam selection cam 17 or the follower moving cam 21.

The second pattern cam 28 is adjacent to a gear 32 that is integral with the worm gear 11 rotatably supported on the amplitude adjustment shaft 6, and the gear has a support arm fixed to the mechanism frame 3. A gear 35 that is rotatable on a support shaft 34 supported by a gear 33 is engaged with the gear 35, and a gear 37 that is integral with the second pattern cam 28 is engaged with a gear 36 that is integral with the gear.

6 to 8 show a second embodiment of the present invention, in which a sleeve 38 is formed at the end of the first pattern cam 10 rotatably supported on the amplitude adjusting shaft 6, and the sleeve 38 is A gear 39 is provided on the end face. A second patterned cam 40 is rotatably fitted on the outer periphery of the sleeve 38, and an internal gear 41 is formed on the end surface of the second patterned cam. A small gear 44 is rotatably supported at three suitable locations on a support plate 43 which is supported by the amplitude adjustment shaft 6 and fixed to the mechanism frame 3 with screws 42 between the forming gear 39 and the gear 39. They are interlocked.

(Operations and Effects) Since the present invention is constructed as described above, when the drive shaft 8 is rotated, the first pattern cam 10 is moved through the worm 9 and the worm gear 11 to the mechanism frames 2 and 3. It is rotated on an amplitude adjustment shaft 6 supported by. When the gear 32 integrated with the worm gear 11 is rotated, the gear 37 integrated with the second pattern cam 28 rotatably supported on the amplitude adjustment shaft 6 via gears 35 and 36 is rotated. Therefore, the second pattern cam 28 is rotated at a different reduction ratio than the first pattern cam 10.

For example, if the reduction ratio of the first pattern cam 10 with respect to the drive shaft 8 is set to 1/18, and the similar reduction ratio of the second pattern cam is set to 1/36, the crescent-shaped sewing pattern will be created using the reduction ratio of 1/18. The first pattern cam has a shape as shown in FIG. 4, and the second pattern cam with a reduction ratio of 1/36 has a shape as shown in FIG. 5. Therefore, the length of the pattern in Figure 4 is L ₁
Then, the length of the elongator pattern in Figure 5 is 2.
It becomes double L ₂ . The setting of the reduction ratio can be determined as appropriate based on the design.

Next, in the second embodiment, when the worm gear 11 is rotated, the gear provided at the end of the first pattern cam 10 moves the second pattern cam 40 through the small gear 44 supported by the support plate 43. internal gear wheel 4
1 is rotated, and thus the second pattern cam 40 is rotated.

The reduction ratio of the second pattern cam to the drive shaft 8 is different from the reduction ratio of the first pattern cam, as in the first embodiment.

When the pattern selection operation section 12 is rotated with respect to the pattern cam driven as described above, the gear 14, the intermediate gear 15, and the gear 16 of the selection shaft 7 of the operation section are rotated.
The selection cam 17 is rotated via. As the selection cam rotates, the terminal 29 of the engagement protrusion 31 of the follower support 24 that engages with the cam becomes parallel to the axial direction of the fixed shaft 5 fixed to the mechanism frames 2 and 3. be forced to move.

By the axial movement of the follower support 24, the cam follower 25 fixed to the follower support is also moved to an appropriate position on the first pattern cam 10 or the second pattern cam 28. It will be done.

The cam follower 25 has a release follower 22 fixed to the follower sliding plate 23 centered on the fixed shaft 5 by a follower release cam 18 which is rotated integrally with the gear 16 when the gear 16 rotates. When one end of the release follower 22 is engaged with the crest of the release cam 18, the end of the cam follower 25 is rotated to the first or second pattern cam 10, 28.
The cam is moved away from the outer circumferential position of the maximum diameter and allowed to move in the direction of the adjacent cam.

Further, by rotating the amplitude adjustment operation section 18, the amplitude cut cam 20 is rotated, and the swinging movement of the follower support 24 is restricted. The swinging motion of the follower support 24 is transmitted to the needle bar support (not shown) via an amplitude rod 46 connected to the lower arm 45, thereby controlling the amplitude movement of the needle.

Since the present invention works as described above,
Various sewing patterns can be easily obtained by the selection operation of the pattern selection operation section 12, and in particular, the sewing pattern shown in FIG. 4 can be obtained as well as the elongator pattern (FIG. 5) of the same pattern. As described above, the first pattern cam and the second pattern cam have different reduction ratios with respect to the drive shaft. By centrally arranging them on one axis within the sewing machine frame, it is possible to significantly reduce the size of the sewing machine, and this has a significant effect on the operation and structure of the sewing machine.

[Brief explanation of the drawing]

The drawings show the embodiments of the present invention, and the drawings show the first embodiment.
3 to 3 show a first embodiment of the present invention, FIG. 1 is a plan view of the present invention, FIG. 2 is a side view of the present invention, FIG. 3 is a partially exploded perspective view of the present invention, and FIG. The figure shows a sewing pattern that can be sewn with the present invention, Figure 5 shows the elongator pattern of the sewing pattern in Figure 4, Figures 6 to 8 show a second embodiment of the present invention, and Figure 6 shows the main points of the present invention. 7 is a cross-sectional view of FIG. 6, FIG. 8 is an exploded perspective view of the main part of the present invention, FIG. 9 is a perspective view of the main part of the present invention, A drive shaft, 10 is a first pattern cam, 12 is a pattern selection operation section, 25 is a cam follower, and 28 is a second pattern cam.

Claims (1)

[Scope of utility model registration request] A drive shaft rotatably supported within the sewing machine frame, a pattern cam interlocked with the rotation of the drive shaft, a cam follower whose one end is removably supported on the outer periphery of the pattern cam, and the cam follower. In a zigzag sewing machine, the first pattern cam is rotated at a reduced speed in conjunction with the drive shaft. and a second pattern cam that is rotated by the drive shaft and has a different reduction ratio than the first pattern cam on the same axis, and by operating the pattern selection operation section, one end of the follower is rotated by the drive shaft and has a different reduction ratio than the first pattern cam. A pattern cam drive mechanism in a zigzag sewing machine, characterized in that the pattern cam drive mechanism is sequentially engaged with and disengaged from a first pattern cam or a second pattern cam.