JPH0768064A - Width changing device of sewing machine for button hole stitch pattern - Google Patents

Abstract

PURPOSE:To prevent difference by an operator from being generated by enabling a plurality of button hole stitch patterns having different widths to be selected by the turning operation of a stitch pattern selecting dial, and providing a button hole stitch pattern size-changing cam on a selecting shaft to be interlocked with the turning operation of the selecting dial, and also connecting a driven element to a stroke adjusting arm. CONSTITUTION:When a button hole stitch selecting dial 40 is rotated, a pattern- selecting cam 46 is rotated, and then a moving plate 63 to be engaged with the cam is moved in the axial direction of a releasing shaft 24. Thereby a driven element 26 is moved in the position of a button hole stitch pattern cam. When the pattern-selecting cam 46 becomes a specific turning movement phase, a button hole stitch selecting cam 50 is interlocked and turned through a button hole arm supported by a selecting shaft 25, and a ratchet tooth is engaged with the first tooth of a ratchet wheel 52. Thereby the driven element 26 on the other end of a moving plate 63 is engaged with the button hole stitch- selecting cam 50, and the moving plate 63 is moved, so as to select the pattern cam.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a buttonhole selection device for a built-in cam type sewing machine incorporating a one-step buttonhole sewing device.

[0002]

2. Description of the Related Art A conventional sewing machine for sewing buttonholes has a buttonhole sewing pattern of which width is constant and only the length can be adjusted. The width of the pattern sewing is adjusted from the minimum to the maximum by using a manual amplitude adjusting device which is arbitrarily adjusted by the operator. It is necessary to perform trial sewing several times to decide whether to set the optimum value by adjusting the width of the buttonhole sewing pattern using the latter amplitude adjusting device. It was necessary to readjust the optimum value when changing to hole sewing.

[0003]

SUMMARY OF THE INVENTION According to the present invention, the adjustment of the width of the buttonhole sewing pattern is performed independently of the amplitude adjusting means used for adjusting the other patterns. It is an object of the present invention to provide an adjusting device which has a simple structure and does not cause a difference between operators depending on the selection.

[0004]

According to the present invention, a buttonhole sewing pattern can be selected by rotating a sewing pattern selection dial and a plurality of buttonhole sewing patterns having different widths can be selected. Further, the size change cam of the buttonhole sewing pattern is provided on the selection shaft interlocked with the rotation operation of the selection dial, and the follower of the size change cam is connected to the amplitude adjusting arm to simplify the structure.

[0005]

According to the present invention, a cam block composed of a pattern cam for buttonholes and other pattern cams which are rotatably supported in the machine frame of the sewing machine and arranged side by side on one axis, and the rotation axis of each pattern cam of the cam block. And a pattern selection cam that is movably supported in parallel with the above-described pattern cam and that is formed with a follower engaged with each of the pattern cams and a moving cam that moves the follower and is rotatably supported in the sewing machine frame. And a selection dial connected to the pattern selection cam via a gear and rotatably supported outside the machine frame, a width changing cam supported coaxially with the pattern selection, and the width changing cam. A width changing follower and an amplitude capable of moving a pin portion slidable in the groove portion of the lateral shake arm while connecting the one end to the width changing follower and the other end to the amplitude rod connected to the needle bar support With the adjustment rod, it is possible to rotate the selection dial. It is obtained as may be made to the width changing pattern selected and buttonhole Nuimoyo.

[0006]

The structure of one embodiment of the present invention will be described below. A drive shaft 2 is horizontally rotatably supported on the upper portion of the sewing machine frame 1 and is rotated by an electric motor 3. A needle bar support 4 is swingably supported around a support shaft 5 at the upper front end of the sewing machine frame 1, and a needle bar 7 having a needle 6 attached to the lower end of the needle bar support 4 moves up and down. It is movably supported.

At the bottom of the machine frame 1 of the sewing machine, a horizontal full rotary hook 8 is provided.
Is rotatably supported, and is rotated via the lower shaft 9 in synchronization with the rotation of the drive shaft 2. Sewing machine frame 1
Further, a feeder is attached to the lower part of the. The feeding device includes a feed dog 10 partially exposed from the lower upper surface of the machine frame at a suitable time, a feed base 11 which is fixed to the feed tooth and is supported for swinging movement, and the feed base is rocked in a horizontal direction. It is composed of a horizontal feed table 12 for moving and a bifurcated arm 13 for swinging the feed table 11 in the vertical direction. The feed device is capable of adjusting the horizontal feed momentum by a feed adjusting device, and the feed pitch of the stitch is adjusted. It can be changed.

A cam mechanism base 14 fixed to the machine frame 1 of the sewing machine.
A cam shaft 15 orthogonal to the drive shaft 2 is supported by the cam shaft 15, and a cam block 16 is rotatably fitted on the cam shaft 15. The cam block includes a worm wheel 18 meshing with a worm 17 fixed to the drive shaft 2, a pattern cam 19 for bar tack as the first step of buttonhole sewing, a pattern cam 20 for subsequent line tack, and a bar tack. A plurality of pattern cams including a pattern cam 21 and a line tuck pattern cam 22 are integrally connected.

A pawl shaft 23, a release shaft 24, and a selection shaft 25 are fixed to the cam mechanism base 44 in parallel with the cam shaft 15. A pawl portion at one end of the pawl shaft 23 is attached to the outer periphery of the pattern cam. The followers 26 and 26 ', which are supported so as to be engageable with the claw shaft 23 and are slidably fitted in the axial direction of the claw shaft 23, the foot portion at the other end of the follower is supported on the claw shaft 23. The follower 26 and the claw plates 27 and 26 'are fitted into the square holes 28 formed in the flat plate portions of the U-shaped claw plates 27 and 27' that are rotatably pivoted.
And 27 'are integrally oscillated (see FIGS. 5 and 3), and the connecting arm 2 provided on the claw plates 27 and 27'.
It is connected to the amplitude rod 36 or the feed adjusting rod 31 via 9 and 29 '.

A U-shaped release arm 32 is rotatably supported on the pawl shaft 23, a release pawl 33 is formed at one end, and a tension spring 34 is provided at an arm formed at the other end. The flat plate portion of the release arm 32 is provided with an adjusting screw 35 which can be engaged with the pawl plate 27 and whose amount of protrusion can be adjusted.

The release shaft 24 has a mountain portion 4 as shown in FIG.
A release cam 36 having a groove 3 and a trough 44 is fixed by a key 37 so as to rotate integrally, and a bevel gear 38 and a spur gear 42 are integrally formed on the release cam 36.

A dial shaft 39, which is orthogonal to the release shaft 24, is rotatably supported on the mechanism base 14, and a selection dial 40 is provided on the outer protruding portion of the machine frame 1 on the dial shaft.
And a bevel gear 41 that meshes with the release cam 36 and a bevel gear 38 that is meshed with the release cam 36 are fixed in the machine frame 1.

A pattern selection cam 46 is fixed to the selection shaft 25 by a pin 45, and a cam is formed on one side surface of the pattern selection cam. Gear 4 on the pattern selection cam 46
7 and a split wheel 48 are integrally formed, the spur gear 42 of the release cam 36 meshes with the gear 47, and one end of a split spring 49 engages with the split wheel 48 to rotate the selection dial 40. A click is given for each distinctive pattern selection.

A buttonhole sewing selection cam 50 is fixed to the selection shaft 25, and a projection 51 is provided on the buttonhole sewing selection cam so as to face the pattern selection cam 46 (see FIG. 4). Further, a ratchet wheel 52 is formed. The ratchet wheel has a toothed portion and a toothless portion on the outer periphery as shown in FIG.
3 in the clockwise direction of FIG.
Then, the bar tuck is sewed by a predetermined number of stitches by being rotated stepwise in the counterclockwise direction.

The ratchet 53 is a ratchet arm 55 pivotally attached to a ratchet arm shaft 54 fixed to the mechanism base 14.
Is rotatably supported at one end of the ratchet wheel 52 and is constantly pressed against the ratchet wheel 52 by a mounted spring 56. A pin 57 provided at the other end of the ratchet arm 55 is supported by the cam shaft 15 by the spring 58 and driven. The ratchet wheel 50 is intermittently rotated in synchronization with the rotation of the drive shaft 2 because it is pressed by the star wheel 59 that rotates in synchronization with the shaft 2.

The buttonhole sewing selection cam 50 is biased counterclockwise in FIG. 7 by the cam return spring 60, and when a pattern other than buttonhole sewing is selected, as shown in FIG. A stopper 61 provided integrally with 50 is engaged with a retaining pin 62 provided on the mechanism base 14, and at this time, the ratchet 53 corresponds to a toothless portion of the ratchet wheel 52 as shown in FIG. Therefore, the buttonhole sewing selection cam 50 is not ratchet driven.

A U-shaped moving body 63 is fitted on the releasing shaft 24 (see FIG. 2), and a claw portion 64 provided at one end of the moving plate is fixed to the selecting shaft 25 by the pattern selecting cam 46. The cam follower 91 is engageably opposed to the cam face of the second follower 91, and the second follower 91 provided at the other end is engageably opposed to the buttonhole sewing selection cam 50, and the arm 65 is further extended. Engages with the groove 66 formed in the boss portion of the follower 26 fitted to the pawl shaft 23. A spring 67 is provided on the side surface of the moving plate 63.
And the claw portion 64 is pressed against the cam surface of the pattern selection cam 46. Therefore, the follower 26 is moved in the axial direction of the pawl shaft 23 by the rotation of the selection dial 40.

A cam groove 68 consisting of a mountain portion and a valley portion is formed on a side surface of the pattern selecting cam 46 opposite to the cam, and the cam groove 68 is rotatable on a shaft portion 69 supported by the mechanism base 14. A first BH arm pin 71 provided on a part of a first BH (button hole) arm 70 pivotally attached to the is engaged.
A first engagement pin 72 that is erected on the other end of the first BH arm is a substantially U-shaped second BH that is rotatably supported by the selection shaft 25.
It is engaged with a groove portion 75 formed in the arm portion 74 of the arm 73 (see FIG. 16).

FIG. 8 shows a state in which the buttonhole sewing selection cam 50 is in substantially the same phase as the state shown in FIG. 5 and the first bar tack of buttonhole sewing is selected. From the state shown, the rotation of the selection dial 40 causes the second BH arm 73 to engage with the protrusion 51 of the buttonhole sewing selection cam 50, and the buttonhole sewing selection cam 5
0 indicates a state in which the spring is rotated counterclockwise in FIG. 8 by a predetermined angle against the action of the cam return spring 60, and the split spring 49 causes a click to stop.

In the state of FIG. 8, the ratchet wheel 52 is positioned so that the ratchet 53 corresponds to the first tooth.

The non-return pawl 76 is pivotally attached to the shaft 77 and is spring 7.
8 is urged to engage the ratchet wheel 52, and the ratchet wheel 52 is locked every time the ratchet is fed after the state shown in FIG.

The reset cam 79 rotatably supported by the selection shaft 25 is for switching the ratchet wheel 52 to the working or non-working state, and has a first and a slightly larger outer diameter than the outer diameter of the ratchet wheel 52. Second projections 80 and 81 are provided (see FIGS. 7 and 8),
Depending on the rotation phase of the reset cam 79, the first protrusion 80
Pushes ratchet 53 out of engagement track or
The ratchet 53 and the reverse rotation preventing claw 76 are pushed up by the protrusion 80 and the second protrusion 81 out of the engagement track. At this time, these are separated.

The reset cam 79 is biased counterclockwise in FIG. 7 by the reset cam spring 83, and normally the stopper 61 provided on the buttonhole sewing selection cam 50 is locked to the locking pin 62 as shown in FIG. Being a ratchet 53
And the non-return pawl 76 are both effective.

The reset plate 84 shown in FIG. 4 is supported by a shaft 85 fixed to the mechanism base 14 so as to be pivotable and slidable in the axial direction. The cutout portion 88 is urged to engage with both the notches 88 across the reset cam 79 and the buttonhole sewing selection cam 50.

When the sewing machine rotates from the state shown in FIG. 8 and the teeth of the ratchet wheel 52 move by three teeth, the notch 88 moves the arm 87, and the engaging portion 89 of the reset cam 79 acts on the arm 87. As shown in FIG. 9, the reset cam 79 is rotated clockwise so that the ratchet 53 is disengaged while the reverse rotation preventing claw 76 is engaged.

The state shown in FIG. 9 corresponds to the line tack without ratchet action subsequent to the first bar tack.
The reset plate 84 is adapted to be actuated in accordance with the positioning position of the BH (button hole) presser, that is, the size of the button hole, and moves upward in the figure against the reset plate spring 86 to move the arm portion. 87 is disengaged from the notch 88, and at this time, the reset cam 79 is rotated counterclockwise and the locking pin 6 is released.
The ratchet drive is reset so that the ratchet drive for the subsequent intermediate bartack is returned until it abuts 2.

The ratchet wheel 52 ratchets five teeth as shown in FIG. 11 for ratcheting three teeth for intermediate bartack, and then for subsequent line tacking.
3 corresponds to the part without teeth.

The release arm 32 is integrally provided with a release release arm 90. The release release arm is rotated by rotating the selection dial 40 at the end of the last line tack so as to repeat the buttonhole. 12 to actuate the selection of the first bartack or other conventional pattern of FIG. 11 by rotating the selection dial 40 from the state of FIG. When the release shaft 23 is rotated in the counterclockwise direction as described above, the reset cam is rotated clockwise on the selection shaft 25 via the pin 91 provided on the reset cam 79 so that the ratchet 53 and the reverse rotation preventing pawl 76 are formed. Are mounted on the first and second protrusions 80 and 81, respectively, so that the ratchet wheel 52 returns to the initial state.

A width changing cam 92 is fixed to the selection shaft 25. The width changing cam includes a large diameter portion 93 and a root diameter portion 94.
Are formed. A width changing follower 96 is swingably supported on a pin shaft 95 supported by the mechanism base 14 on the outer periphery of the width changing cam, and a pawl 97 at one end is provided with the width changing cam 92.
Is engaged with the outer circumference of the sewing machine frame 1 at the other end 98.
It is connected to an amplitude adjusting rod 103 for varying the position of a tip pin portion 102 of an amplitude rod 101 which is slidable in a groove portion 100 of a lateral swing arm 99 pivotally attached to. The tip of the amplitude rod 101 is connected to one end of the needle bar support 4.

The present invention has the above-described structure. FIG. 7 shows a state in which a normal pattern other than buttonhole sewing, that is, the general pattern in FIG. 13 is selected, and the ratchet wheel 52 ratchets a toothless portion. The buttonhole sewing selection cam 50 and the reset cam 79 are both positioned and stopped by the locking pin 62 even if the ratchet 53 moves as the sewing machine operates.

Next, when the selection dial 40 is rotated to select the buttonhole sewing, the pattern selection cam 46 is rotated, so that the moving plate 63 that engages with the pattern selection cam is moved to the release shaft 24. The follower 26 is moved in the axial direction to the position of the buttonhole sewing pattern cam. When the pattern selection cam 46 reaches a predetermined rotation phase related to buttonhole sewing, the projection 51 of the buttonhole sewing selection cam 50 contacts the second BH arm 73 supported by the selection shaft 25, and the pattern selection cam 46 continues. When the buttonhole sewing selection cam 50 is rotated in the clockwise direction in FIG. 7 in response to the rotation of the ratchet wheel 53 and is rotated to a position where the ratchet 53 is locked to the first tooth of the ratchet wheel 52 in FIG. When the second follower 91 at the other end of the plate 63 is engaged with the buttonhole sewing selection cam 50, the moving plate 63 is further moved to select the first bartack pattern cam 19 (first step in FIG. 13). .

Next, when the sewing machine is operated, bartack sewing of the first step shown in FIG. 13 is performed. That is, the star wheel 59 rotates, the ratchet 53 operates, and the stitches (in this case, 2 stitches) are turned clockwise in FIG. 8 to sew 6 stitches. The reset cam 79 is engaged with the engaging portion of the reset cam 79 via the arm portion 87 of the reset plate 84, and the reset cam 79 rotates clockwise by a predetermined angle, and the first protrusion 80 releases the ratchet 53 from the ratchet wheel 52. Let At this time, the follower 26 corresponds to the pattern cam 20 for line tacking (FIG. 13).
Second step shown in FIG.

After sewing the line tack of the desired length,
When the selection dial 40 is pushed in, the reset arm 87 of the reset plate 84 causes the notch portion 8 of the buttonhole sewing selection cam 50.
8, the reset cam 79 returns and rotates in the counterclockwise direction in FIG. 9, and the ratchet 53 enters the operating state.

When the sewing machine is rotated, the follower 26 corresponds to the position of the pattern cam 21 for the next bar tack (FIG. 1).
3rd step shown in 3.). When the bartack is formed for 6 stitches, the ratchet wheel 52 has no teeth corresponding to the ratchet 53 as shown in FIG. At this time, the follower 26 corresponds to the pattern cam 22 for the final line tack.

After forming the line tack of the desired length,
When the selection dial 40 is rotated to repeat the buttonhole sewing, the release cam 36 causes the release arm 32 to rotate counterclockwise as shown in FIGS.
Is rotated clockwise by a pin 91 provided on the side surface,
The first and second protrusions 80 and 81 release the ratchet 53 and the check claw 76, respectively, and the ratchet wheel 5
No. 2 is returned to the state of FIG. 7 and is formed by repeating buttonhole sewing similarly to the above process.

When the width of the buttonhole sewing pattern is changed, the selection dial 40 is rotated to select a buttonhole sewing pattern having a desired width, so that the buttonhole sewing pattern having a large or small size can be obtained. In the present embodiment, the buttonhole sewing pattern cams 19, 20, 21, 22 are selected by the rotation of the selection dial 40, and at the same time, the width changing follower 96 is moved by the width changing cam 92.
Is rotated. When the size is large, the claw 97 at one end of the width-change follower contacts the large diameter portion 93 of the cam, and when the size is small, it contacts the root diameter portion 94 of the cam. The amplitude adjusting rod 103 connected to the width changing follower 96 rotates the amplitude rod 101 connected to the needle bar support 4 to adjust the position of the tip pin portion 102 fitted in the groove portion 100 of the lateral shake arm 99. , Adjust the needle bar amplitude. In this way, the width of the buttonhole sewing pattern can be changed to two kinds of widths by rotating the selection dial 40. Therefore, if the root diameter of the width changing cam 92 is set to two steps, it is natural that buttonhole sewing patterns of three kinds of widths can be obtained.

In FIG. 14, when the general pattern is selected, the cam groove 68 of the pattern selection cam 46 and the first BH that engages with the cam groove 68 are selected.
1 shows the position of the arm 70 relative to the pin 71.
5 shows a state when a buttonhole sewing pattern with a small width is selected, and FIG. 16 shows a state when a buttonhole sewing pattern with a large width is selected.

In the present invention, in order to change the width of the buttonhole sewing pattern, the selection dial is rotated to select a desired one from a plurality of buttonhole sewing patterns, so that a buttonhole having a large width or a small buttonhole is selected. It is possible to form buttonholes of different widths. Since the width size is fixed, the operator can reproduce it many times.

[0039]

[Effect] According to the present invention, since the buttonhole sewing pattern width changing cam is built in the sewing machine frame, the buttonhole sewing patterns having different widths can be easily selected by rotating the selection dial, so that it is suitable for beginners. Can be reproduced easily, and is extremely effective in practical use.

[Brief description of drawings]

1 shows an embodiment of the present invention, FIG. 1 is an overall perspective view of a sewing machine incorporating the present invention device, FIG. 2 is a sectional side view of a sewing machine incorporating the present invention device, and FIG. 3 is the present invention device. 4 is a plan view of a main part of the device of the present invention, FIG. 5 is a side view of a main part of the device of the present invention, FIG. 6 is a cross-sectional plan view of the main part of the device of the present invention, and FIG. 8 is a sectional rear view of an essential part of the device of the present invention, FIG. 9 is a sectional rear view of an essential part of the device of the present invention, and FIG. 10 is a sectional rear view of an essential part of the device of the present invention.
FIG. 12 is a sectional rear view of an essential part of the device of the present invention, FIG. 12 is a sectional rear view of an essential part of the device of the present invention, FIG. 13 is a step progression explanatory diagram of buttonhole sewing in the device of the present invention, and FIG. FIG. 15 is a front view of a main part of the device of the present invention,
FIG. 16 is a front view showing the main part of the device of the present invention. 1 ... Sewing machine frame 4 ... Needle bar support 16 ... Cam block 26 ... Follower 40 ... Selection dial 46 ... Pattern selection cam 92 ... Width change cam 96 ... Width change follower 99 ... Lateral arm 100 ... Groove 101 ... Amplitude Rod 102 ... Pin portion 103 ... Amplitude adjusting rod

Claims (1)

[Claims] A cam block 16 composed of a pattern cam for buttonholes and a plurality of other pattern cams that are rotatably supported in the sewing machine frame 1 and arranged in parallel on one axis, and a rotation axis of each pattern cam of the cam block. And a pattern selection cam 46 that is rotatably supported in the sewing machine frame and that forms a follower 26 that is movably supported on the pattern cam and that is engaged with each of the pattern cams, and a moving cam that moves the follower. A selection dial 40 connected to the pattern selection cam via a gear and rotatably supported outside the machine frame; a width changing cam 92 supported coaxially with the pattern selection cam 46; and a width changing cam. And a width change follower 96 engaged with the width change follower, one end of which is connected to the width change follower and the other end of which is connected to the amplitude rod 101 which is connected to the needle bar support 4 and slides in the groove portion 100 of the lateral swing arm 99. Amplitude adjustment that can move the pin 102 Width changing device buttonhole Nuimoyo sewing machine characterized by comprising a rod 103.