JP2013240574A - Sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accelerate the rotation action of a needle.SOLUTION: A sewing machine includes: a needle bar 12 which holds a sewing needle 11; a needle bar rotation base 31 which supports the needle bar in a vertically movable way and which is rotatably supported around a center line C of the needle bar together with the needle bar by a sewing machine frame 101; a needle vertical movement mechanism 20 which is connected to the needle bar and which applies vertical motion to the needle bar; a needle rotation motor 32 which becomes a drive source of the rotation motion of the needle bar; and a thread take-up lever 14 which performs the take-up of a needle thread. The needle bar rotation base supports one part of the needle bar in a vertically movable way, and the needle vertical movement mechanism is connected rotatably at the other position which does not overlap with the one part of the needle bar which is supported by the needle bar rotation base.

Description

  The present invention relates to a sewing machine that rotates a needle bar.

In the case of a sewing machine that holds a cloth with a cloth holding frame and positions it at an arbitrary position on a horizontal plane in synchronization with the vertical movement of the needle bar to form an arbitrary seam, such as an XY feed sewing machine, Since the eye hole remains in a certain direction, the quality of the sewing state varies depending on the movement direction of the fabric.
For this reason, in a conventional sewing machine, a drive device that imparts a rotation operation around the needle bar is attached to a needle bar base that supports the needle bar so that the needle bar can be moved up and down, and the needle bar is rotated according to the movement direction of the fabric. Improvement of the sewing state was attempted (for example, see Patent Document 1).

Chinese Patent Application Publication No. 1018545718

  However, the above-mentioned conventional sewing machine has a problem that the needle bar base is heavy and it is difficult to increase the rotation speed of the needle bar, and accordingly, the sewing speed cannot be increased.

  An object of the present invention is to increase the speed of needle bar rotation.

  According to the first aspect of the present invention, a needle bar for holding a sewing needle, a needle bar that supports the needle bar so as to be movable up and down, and is supported so as to be rotatable around a center line of the needle bar together with the needle bar. A rotating base, a needle up-and-down moving mechanism that is connected to the needle bar and imparts an up-and-down movement to the needle bar, a needle rotating motor that is a driving source for the rotating operation of the needle bar, and a needle thread pull-up In the sewing machine, the needle bar rotating table supports a part of the needle bar so that the needle bar can move up and down, and the needle vertical moving mechanism supports the needle bar by the needle bar rotating table. It is characterized in that it is connected to a part to be rotated at another position where it does not overlap.

  The invention according to claim 2 has the same configuration as that of claim 1, and the needle bar has a pair of convex portions protruding toward both outer sides in the diametrical direction centering on the needle bar, and the needle The rod turntable includes two guide holes or guide grooves along the vertical direction in which each of the convex portions fits and slides.

  The invention according to claim 3 has the same configuration as that of claim 1 or 2, the needle bar rotating base supports the upper part of the needle bar so as to be movable up and down, and the needle vertical movement mechanism is The needle bar is pivotally connected to the needle bar below the needle bar rotating base.

  The invention described in claim 4 has the same configuration as that of any one of claims 1 to 3, and includes a hook that captures the upper thread and entangles the upper thread with the lower thread by a rotating operation, and the hook. A hook rotation base supported rotatably about the same center line as the needle bar with respect to the sewing machine frame, and a hook rotation motor serving as a drive source for the rotation operation of the hook rotation base, A synchronization control unit is provided for controlling the needle rotation motor and the hook rotation motor so that the rotation angles of the needle bar rotation table and the hook rotation table coincide with each other.

The invention according to claim 5 has the same configuration as that of any one of claims 1 to 4, and further includes a moving mechanism capable of moving the workpiece in an arbitrary direction on a horizontal plane.
A follow-up control unit that controls the needle rotation motor so that the needle bar rotates in a direction corresponding to the moving direction of the sewing product when the sewing mechanism is moved by the moving mechanism. It is characterized by providing.

  The invention according to claim 6 has the same configuration as that of claim 5, and a fixed reference position is determined for the rotation angle of the needle bar, and when the needle bar is rotated, the target position is the current position. A selection control unit that selects either the forward or reverse rotation direction so that the rotation angle from the rotation angle decreases, and when performing a plurality of rotation operations, the total rotation angle is determined in advance from the reference position. And a restriction control unit that selects either the forward or reverse rotation direction that does not exceed the maximum rotation angle regardless of the selection by the selection control unit when the maximum rotation angle is exceeded.

In the first aspect of the present invention, the needle bar rotating base supports a part of the needle bar, and the needle up-and-down moving mechanism is connected to the needle bar at another position that does not overlap with the needle bar rotating base. Compared to the structure in which the needle bar rotating base supports the upper and lower ends of the needle bar so that the needle bar can be rotated, and the needle bar and the needle vertical movement mechanism are connected between the support positions of the needle bar rotating base. Thus, the needle bar rotation base can be reduced in size in the vertical direction, and the weight can be reduced by this, so that the high-speed rotation operation is facilitated, and the sewing speed can be increased.
In particular, in the invention according to claim 3, the needle bar rotating base supports the upper part of the needle bar, and the needle vertical movement mechanism is connected to the needle bar below the needle bar rotating base. It is advantageous for downsizing of the table in the vertical direction, and it is possible to effectively realize weight reduction and high-speed rotation.

According to the second aspect of the present invention, the needle bar has a pair of convex portions, and the needle bar rotating base supports each convex portion with two guide holes or guide grooves. Accordingly, it is possible to improve the followability of the rotation operation of the needle bar with respect to the needle bar, and it is possible to perform a favorable rotation operation.
Furthermore, with the above structure, the needle bar can be favorably moved up and down with respect to the needle bar rotation base, and high-speed sewing can be stably performed.

  According to a fourth aspect of the present invention, when the hook can be rotated, the hook is also rotated when the needle bar is rotated, so that the needle thread can be smoothly fed from the sewing needle whose hook is changed in direction. Thus, the sewing operation can be performed reliably and smoothly.

  The invention according to claim 5 controls the needle rotation motor so that the needle bar rotates following in the direction corresponding to the moving direction of the sewing object. Therefore, when the upper thread is pulled up by the balance, Occurrence of untwisting of the upper thread pulled out from the stitch hole of the sewing needle can be reduced, and fraying and unraveling of the thread can be prevented and better sewing can be performed.

According to the sixth aspect of the present invention, since a small rotation angle is selected by the selection control unit, the speed of the rotation operation can be increased.
On the other hand, as a result of repeated rotation of the needle bar, if the rotation angle of the needle bar from the reference position increases, the supplied upper thread may be entangled with the needle bar. Since the control is performed so that the maximum rotation angle is not exceeded, it is possible to solve the problem of the entanglement of the upper thread with respect to the needle bar and to perform a satisfactory sewing operation.

It is a perspective view of a sewing machine of a first embodiment. It is the block diagram which illustrated schematically the mechanism structure of the sewing machine. It is sectional drawing which notched a part of sewing machine arm part. It is a perspective view of the structure around a needle bar. It is a longitudinal cross-sectional view of the structure around the needle bar. It is sectional drawing along the WW line of FIG. It is a perspective view of a shuttle mechanism and a differential transmission mechanism. It is sectional drawing along the centerline and YZ plane of the needle bar of a shuttle mechanism and a differential transmission mechanism. FIG. 9A is an explanatory diagram of a state in which the hook transmission portion rotates the hook by the rotation of the hook rotation base and the support frame, and FIG. 9A shows a state before the hook rotation base and the support frame rotate. (B) shows the state after rotation of the shuttle turntable and the support frame. It is a top view of a shuttle mechanism. It is the perspective view which mainly showed the opener action | operation part of the shuttle mechanism. It is the perspective view which mainly showed the knife mechanism of the shuttle mechanism. 13A is a horizontal sectional view of the oil supply mechanism, and FIG. 13B is a vertical sectional view of the oil supply mechanism. It is a block diagram which shows the control system of a sewing machine. It is explanatory drawing which showed the sewing direction which a hitch stitch generate | occur | produces on the XY plane when the direction which goes to the shuttle from the centerline of a needle bar is made into a reference | standard. It is a flowchart of hitch stitch avoidance control. It is explanatory drawing which shows the upper thread | yarn path | route in a sewing machine. It is explanatory drawing which shows the relationship between the contact position with respect to the stitch hole of the sewing needle of an upper thread | yarn, and generation | occurrence | production of twist back, FIG. 18 (A) shows the example in which twist back generate | occur | produces, FIG. An example that does not occur is shown. It is explanatory drawing which shows the relationship of the sewing direction in which the twist return with respect to a sewing needle generate | occur | produces. It is explanatory drawing of the operation example in the case of performing needle bar rotation control. It is a flowchart of needle bar rotation control. It is explanatory drawing which shows the upper thread | yarn path | route in the sewing machine of 2nd embodiment. It is a perspective view around a sewing needle. FIG. 24 is a perspective view of the periphery of the sewing needle as seen from a different line of sight from FIG. 23. FIG. 25A is a front view of the knife needle at the reference position, and FIG. 25B is a side view of the knife needle 11A at the reference position. The top view of the knife needle in a reference position is shown. It is explanatory drawing of a rectangular-shaped sewing pattern along the outer edge part of a rectangular to-be-sewn thing. It is explanatory drawing which shows the seam by the saddle stitch style sewing by the sewing machine which has a needle bar rotation mechanism equipped with the knife needle. It is explanatory drawing which shows the stitch by the cloth movement mechanism of the conventional sewing machine which does not perform knife needle rotation. It is explanatory drawing which shows the seam by the improper saddle stitch style sewing by a sewing machine. It is explanatory drawing which shows the sewing operation | movement of the saddle stitch style sewing specifically defined in the sewing data. It is a front view which shows the other example of a flat knife type knife needle. It is a top view which shows the other example of a flat knife type knife needle. It is a front view which shows the other example of a flat knife type knife needle. It is a top view which shows the other example of a flat knife type knife needle. It is a front view which shows the other example of a flat knife type knife needle. It is a top view which shows the other example of a flat knife type knife needle. It is another example of a sewing pattern. It is a further another example of a sewing pattern. It is sectional drawing in alignment with the center line and YZ plane of the shuttle rotation mechanism of the example which mounted the shuttle drive motor in the shuttle rotation base, and the shuttle mechanism. It is sectional drawing which shows the example which equipped the sewing machine of FIG. 40 with the slip ring.

[Outline of First Embodiment]
A first embodiment of the present invention will be described with reference to FIGS.
A sewing machine 100 described below as the present embodiment is a so-called electronic cycle sewing machine, and has a holding frame as a cloth holding portion that holds a cloth that is a sewing object to be sewn, and the holding frame is attached to the sewing needle. By relatively moving, a sewing pattern based on predetermined sewing data is formed on the fabric held by the holding frame.
FIG. 1 is a perspective view of a sewing machine 100 according to the present invention, and FIG. 2 is a configuration diagram schematically showing a mechanism structure of the sewing machine 100.
Here, the direction in which the sewing needle 11 to be described later moves up and down is defined as the Z-axis direction (vertical direction), and one direction orthogonal thereto is defined as the X-axis direction (left-right direction), both the Z-axis direction and the X-axis direction. The direction perpendicular to the Y axis direction is defined as the Y axis direction (front-rear direction).

  The sewing machine 100 includes a needle bar 12 that holds the sewing needle 11 at its lower end and moves up and down along the Z-axis direction, and a needle up-and-down moving mechanism 20 that moves the sewing needle up and down using the sewing machine motor 21 as a drive source. A needle bar rotating mechanism 30 that rotates the needle bar 12 about its center line along the Z-axis direction, and a hook mechanism 800 including a hook 801 that entangles the lower thread with the upper thread passed through the sewing needle 11; A differential transmission mechanism 400 that includes an input shaft 411 and an output shaft 412 that transmit the power of the rotation of the hook from the hook drive motor 401 as a driving means to the hook mechanism 800, and that can change and adjust the phase difference between these shafts; , A cloth movement mechanism 102 as a movement mechanism for arbitrarily moving and positioning along the XY plane, a control device 110 as an operation control means for controlling the operation of each of the above components, and each configuration of the sewing machine 100 Support A sewing machine frame 101 that includes a middle presser 13, and a balance mechanism 14 mainly comprises.

[Sewing frame]
As shown in FIG. 1, the sewing machine 100 includes a sewing machine frame 101 whose outer shape is substantially U-shaped when viewed from the X-axis direction. The sewing machine frame 101 includes a sewing machine arm portion 101a that extends above the sewing machine 100 and extends in the Y-axis direction, a sewing machine bed portion 101b that extends below the sewing machine 100 and extends in the Y-axis direction, a sewing machine arm portion 101a, and a sewing machine bed portion 101b. And a vertical body 101c.

[Cloth movement mechanism]
As shown in FIG. 1, the cloth moving mechanism 102 includes a holding frame 102a that holds an article to be sewn on the upper surface of the sewing machine bed portion 101b, a support arm 102b that supports the holding frame 102a to be movable up and down, and a support arm 102b. An X-axis motor 102c (see FIG. 14) that moves the holding frame 102a in the X-axis direction, and a Y-axis motor 102d (see FIG. 14) that moves the holding frame 102a in the Y-axis direction via the support arm 102b. ing.
With this configuration, the cloth moving mechanism 102 can move and position the workpiece to an arbitrary position on the XY plane via the holding frame 102a, and can perform needle dropping at an arbitrary position for each stitch. It is possible to form a free seam.

[Needle vertical movement mechanism]
3 is a cross-sectional view in which a part of the sewing machine arm portion 101a is cut out, FIG. 4 is a perspective view of the configuration around the needle bar 12, and FIG. 5 is a vertical cross-sectional view of the configuration around the needle bar 12.
As shown in FIGS. 1 to 5, the needle up-and-down moving mechanism 20 includes an upper shaft 22 that is rotatably supported in a state along the Y-axis direction in the sewing machine arm portion 101 a, and an end portion of the upper shaft 22. A sewing machine motor 21 for applying a rotational force, a needle bar crank 23 provided at the other end of the upper shaft 22, a crank rod 24 having one end connected to an eccentric position with respect to the center of rotation of the needle bar crank 23, a needle A needle bar holder 25 that is engaged with the periphery of the bar 12 and is fixed by a screw (not shown), and a transmission member 26 that transmits vertical movement from the crank rod 24 to the needle bar 12 via the needle bar holder 25 are provided. Yes.
The upper shaft 22 is directly connected to the output shaft of the sewing machine motor 21 and is driven to rotate. The rotation of the upper shaft 22 is converted into a reciprocating motion up and down by a needle bar crank 23 and a crank rod 24 to transmit the transmission member 26 and the needle bar. It is transmitted to the needle bar 12 via the hug 25.

The transmission member 26 is used to insert the needle bar holder 25 between the top plate part 261 and the bottom plate part 262 and the top plate part 261 and the bottom plate part 262 at the time of assembly. The opening 263 is provided.
Each of the top plate portion 261 and the bottom plate portion 262 is formed with a through hole into which the needle bar 12 can be inserted in the central portion in plan view. The needle bar 12 is inserted into each through hole, and the top plate portion 261 and By clamping and fixing the needle bar holder 25 between the bottom plate portions 262, the transmission member 26 and the needle bar 12 are interlocked in the vertical direction, and the needle bar 12 is rotated around the center line C (see FIG. 2). To enable movement.

Furthermore, the transmission member 26 includes a support shaft 264 along the Y-axis direction, and a lower end portion of the crank rod 24 supports the support shaft 264 through a metal bearing so as to be rotatable. The support shaft 264 passes through the crank rod 24 and is connected to the square piece 265 behind the crank rod 24.
The square piece 265 has a rectangular shape, and on both sides in the X-axis direction, guide grooves 101d for vertically moving the square piece 265 without rotating are formed on the inner wall of the sewing machine arm portion 101a. .
Therefore, when the lower end portion of the crank rod 24 moves up and down, the transmission member 26 is prevented from swinging around the support shaft 264 and shaken in the X-axis direction, and transmits a stable vertical movement operation to the needle bar 12. It is possible to do.

[Needle bar rotation mechanism]
The needle bar 12 is supported by a lower needle bar metal (metal bearing) 122 on the lower end side so that the needle bar 12 can be moved up and down and rotated around the center line C, and the upper end side is supported by the needle bar of the needle bar rotating mechanism 30. An upper needle bar metal (metal bearing) 121 provided at the lower end of the turntable 31 is supported so as to be movable up and down.
Furthermore, the lower end portion of the needle bar 12 holds the sewing needle 11, and the upper end portion is equipped with a rectangular plate 123 that serves as a detent for the needle bar rotating base 31. The rectangular plate 123 is inserted through a through groove 12a formed in the upper portion of the needle bar 12, and is fixed by a screw (not shown). For this reason, the rectangular plate 123 protrudes from the needle bar 12 on both sides in the diameter direction of the circle centering on the needle bar 12, and these protruding parts constitute a pair of convex parts 123a and 123b.
Although the needle bar 12 and the rectangular plate 123 are configured as separate parts, instead of this, it is easily conceivable to integrally form a pair of convex portions on the needle bar.

  The needle bar rotating mechanism 30 includes a cylindrical needle bar rotating base 31 that supports the needle bar 12 so as to be movable in the up and down direction, and a drive source for a rotating operation around the center line C of the needle bar rotating base 31. A needle rotation motor 32 and a transmission mechanism 33 for transmitting a rotation operation from the needle rotation motor 32 to the needle bar rotation base 31.

The upper and lower end portions of the needle bar rotating base 31 are supported by metal bearings 311 and 312 so as to be rotatable around the center line C. The upper metal bearing 311 is fixedly installed near the upper surface of the sewing machine arm portion 101a.
The lower metal bearing 312 is held by a support member 313 attached to the wall surface of the sewing machine arm portion 101a via a support arm portion 312a (FIG. 4) extending radially outward.
Since the needle bar rotating base 31 is supported at two places in the upper and lower directions, the needle bar rotating table 31 can be firmly maintained in the vertical vertical direction, and the needle bar 12 can be smoothly moved up and down.
In addition, since the needle bar 12 is also supported by the upper and lower needle bar metals 121, 122, the needle bar 12 and the needle bar rotating base 31 can be firmly maintained in the vertical vertical direction.

  Further, the needle bar rotating base 31 has elongated hole-shaped openings along the Z-axis direction formed on both side surfaces in the Y-axis direction in FIG. 5, and each of the openings has a long guide plate 314. , 314 are screwed and fixed at two locations on the top and bottom. Each guide plate 314, 314 is formed with a long hole 314a penetrating along the Z-axis direction, and the convex portions 123a, 123b of the needle bar 12 are inserted into the long holes 314a, 314a from the inside thereof. . The width of the elongated hole 314a is slightly wider than the width of the convex portions 123a and 123b, thereby enabling the convex portions 123a and 123b to slide along the elongated hole 314a. That is, the needle bar 12 rotates around the center line C together with the needle bar rotating base 31 without hindering the vertical movement by the cooperation of the guide plates 314, 314 and the convex portions 123a, 123b of the needle bar 12. It is possible to do.

The transmission mechanism 33 includes a motor bracket 331 that supports the needle rotation motor 32 with its output shaft facing downward, and a protruding end portion of the needle bar rotation base 31 from the upper surface of the sewing machine arm portion 101a by a bearing 334. A support bracket 333 rotatably supported, a main sprocket 332 fixedly mounted on the output shaft of the needle rotating motor 32, a driven sprocket 335 fixedly mounted near the protruding end of the needle bar rotating base 31, And a timing belt 336 that is stretched over a main sprocket 332 and a driven sprocket 335.
Accordingly, when the needle rotation motor 32 is driven, rotation is applied to the needle bar rotation base 31, and the needle bar 12 can be rotated together with the needle bar rotation base 31.
Note that the center line of the needle bar 12, the rotation center line of the needle bar rotation base 31, and the rotation center line of the hook rotation base 130, which will be described later, are all on the same straight line. Let's say.

[Center press]
The intermediate presser 13 moves up and down in synchronism with the needle bar 12 by a known motion transmission mechanism (not shown) using the sewing machine motor 21 as a drive source, like the needle bar 12.
The intermediate presser 13 moves up and down a cylindrical frame in which the sewing needle 11 is loosely inserted with an amplitude smaller than that of the needle bar 12 just above the cloth, and the cloth cannot be pulled up when the sewing needle 11 moves upward. In this way, the fabric is pressed down.

[Balance mechanism]
The balance mechanism 14 includes a link member 141 whose one end is pivotally supported by an eccentric shaft that supports the upper end of the crankshaft 24 provided on the needle bar crank 23, and a bell crank member 143 having a balance 142. Yes.
The bell crank member 143 has a base portion pivotally supported inside the sewing machine arm portion 101a and two arm portions extending from the base portion, and one arm portion extends to the outside of the sewing machine arm portion 101a. The balance 142 is made. The other arm 143 a is connected to the other end of the link member 141, and a rotation operation is input to the bell crank member 143.
The balance 142 has a through-hole through which the upper thread U is inserted at the tip.
With this configuration, in the balance mechanism 14, the balance 142 moves up and down at the same cycle as the needle bar 12. However, the balance 142 is designed so as to reach the top dead center with a delay of about 60 ° in the upper shaft angle from the needle bar 12.

[Cook turntable]
7 is a perspective view of the hook rotation base 130, the hook mechanism 800, and the differential transmission mechanism 400, and FIG. 8 is a cross-sectional view taken along the center line C and the YZ plane. The shuttle turntable 130 will be described with reference to FIGS. 2, 7, and 8.
The shuttle turntable 130 is attached to the mounting plate 131 on which the shuttle mechanism 800 is mounted on the upper surface along the XY plane, the upper frame 132 attached to the lower surface of the mounting plate 131, and the lower portion of the upper frame 132. The mounting plate 131, the upper frame 132, and the lower frame 133 are integrated by screwing.
The shuttle turntable 130 is supported at its upper and lower portions by a support frame 105 that forms a part of the sewing machine frame 101 so as to be rotatable around the center line C via bearings 134 and 135.

[Differential transmission mechanism]
The differential transmission mechanism 400 has a function of applying a rotational force from the hook drive motor 401 to the hook 801 of the hook mechanism 800 mounted on the upper surface of the hook rotating base 130, and It has a function of applying rotational power from the dynamic motor 402 and a function of correcting fluctuations in the phase around the hook shaft 811 due to the rotation of the hook 801.
The hook 801 is a so-called full-rotation horizontal hook, and is fixedly mounted on a hook shaft 811 parallel to the center line C on the lower side of the cloth placing plate 103. It is supported so as to be rotatable around its axis.

  The differential transmission mechanism 400 includes a rotational force transmission unit 410 that transmits rotational force to the shuttle mechanism 800, and a rotational power transmission unit that rotates the shuttle turntable 130 to turn the shuttle 801 around the center line C. 420, a differential mechanism portion 430 that corrects a phase variation around the hook shaft 811 generated in the hook 801 due to the rotation, and a rotary power input from the driven sprocket 422, and the hook rotation base 130 and a support frame 431 described later. And a pivot interlocking portion 440 as a pivot interlocking mechanism for pivoting the shuttle pivot base 130 by a double pivot amount of the support frame 431. It has.

[Differential transmission mechanism: Rotational force transmission part]
The rotational force transmission unit 410 includes a shuttle drive motor 401 serving as a rotational drive source of the shuttle 801, an input shaft 411 to which torque from the shuttle drive motor 401 is input, and torque from the input shaft 411 via the differential mechanism 430. Is transmitted to the hook mechanism 800 and is output to the hook mechanism 800, a main sprocket 413 provided on the output shaft of the hook drive motor 401, a driven sprocket 414 fixedly provided on the lower end of the input shaft 411, and An internal tooth timing belt 415 spanned over the sprockets 413, 414, an output sprocket 416 fixed to the upper end of the output shaft 412, and a loop between the output sprocket 416 and the input sprocket 822 of the hook mechanism 800. A timing belt 417 of the delivered internal teeth.

  The shuttle drive motor 401 is fixed to the support frame 105 with the output shaft directed downward, and the output shaft is equipped with a main sprocket 413.

The input shaft 411 and the output shaft 412 are rotatably supported by a lower portion and an upper portion of a support frame 431 of the differential mechanism section 430 described later. These input / output shafts 411 and 412 are both connected to the center line C. It is arranged on the same line.
A driven sprocket 414 is provided at the lower end of the input shaft 411, and torque is input from the shuttle drive motor 401 via the main drive sprocket 413 and the timing belt 415.
An output sprocket 416 is provided at the upper end of the output shaft 412, and torque is input from the input sprocket 822 to the shuttle mechanism 800 via the timing belt 417.

[Differential transmission mechanism: Rotating power transmission unit]
The rotational force transmission unit 420 includes a hook rotation motor 402 that is a rotation driving source of the hook 801, a main sprocket 421 mounted on the output shaft of the hook rotation motor 402, and an upper frame 132 of the hook rotation table 130. A driven sprocket 422 as a driven member fixedly provided on the outer periphery of the upper portion, and an internal tooth timing belt 423 stretched over the sprockets 421 and 422 are provided.
With these configurations, torque is input from the hook rotation motor 402 to the hook rotation base 130 via the sprockets 421 and 422 and the timing belt 423, and a center line is formed on the upper surface of the mounting plate 131 of the hook rotation base 130. A rotating motion around the center line C is applied to the hook 801 provided at a position eccentric from C.

[Differential transmission mechanism: Differential mechanism]
The differential mechanism portion 430 is fixedly mounted on the support frame 431 that rotatably supports the input shaft 411 and the lower end portion of the output shaft 412 facing each other and the upper end portion of the input shaft 411. A transmission bevel gear 435 that meshes with both the first bevel gear 432, the second bevel gear 433 fixedly installed at the lower end of the output shaft 412, and the first and second bevel gears 432 and 433 facing each other. And a transmission body 434 including

The support frame 431 is supported by the hook rotation base 130 so as to be rotatable around the center line C with respect to the hook rotation base 130. The support frame 431 and the hook rotation base 130 are individually center lines. It is possible to rotate around C.
An input shaft 411 is supported concentrically through a bearing at the lower center of the support frame 431, and an output shaft 412 is supported concentrically through the bearing at the upper center.

Furthermore, the intermediate part in the up-down direction of the support frame 431 has a substantially rectangular frame-like structure, and the transmission body 434 is rotatably supported by the frame-like part.
The transmission body 434 passes between the opposed ends of the input shaft 411 and the output shaft 412 and has a shaft portion 436 provided on a line orthogonal to the center line C, and a transmission bevel gear 435 fixedly mounted on the shaft portion 436. The shaft portion 436 is rotatably supported by the support frame 431 via a bearing.
The transmission bevel gear 435 meshes with both the first and second bevel gears 432 and 433, and is interposed between the input shaft 411 and the output shaft 412 via the first and second bevel gears 432 and 433. Thus, it is possible to transmit rotations in the opposite directions.
With this structure, the differential mechanism 430 constitutes a so-called differential gear mechanism.

FIG. 9 is an explanatory diagram showing the influence on the rotation amount of transmission between the input shaft 411 and the output shaft 412 due to the rotation of the support frame 431 of the differential mechanism section 430.
The first bevel gear 432 and the second bevel gear 433 have the same number of teeth and are transmitted in the opposite rotation directions, but the transmission speed ratio is 1: 1.
For example, when rotation is transmitted from the input shaft 411 to the output shaft 412, if the support frame 431 rotates about the input shaft 411 and the output shaft 412 by an angle α, the transmission bevel gear 435 is moved to the first bevel gear 435. The gear 432 is rotated by the number of teeth of the angle α, and the transmission bevel gear 435 rotates the second bevel gear 433 by the angle α. Further, since the support frame 431 is rotated by an angle α, the second bevel gear 433 is rotated by an angle 2α that is the sum of the rotation of the transmission bevel gear 435 and the rotation of the support frame 431. Will occur. That is, the rotation of the support frame 431 in a certain direction causes an angle difference corresponding to twice the rotation angle of the output shaft 412 in the rotation direction of the support frame 431 with respect to the input shaft 411.

[Differential transmission mechanism: Rotation interlocking part]
The rotation interlocking portion (rotation interlocking mechanism) 440 is configured so that the support frame 431 is viewed in the same direction (the same direction when viewed from the operator's basis, that is, when viewed from the shuttle rotating table 130 when the shuttle rotating table 130 is rotated. Although the support frame 431 appears to rotate in the reverse direction, when viewed from the operator's viewpoint, the support frame 431 rotates in the same direction with half the amount of movement of the rotary table 130). It is to rotate in conjunction with.
The rotation interlocking unit 440 is fixed to the support shaft 105, fixed to the support frame 105, fixed to the support shaft 442, and to the support shaft 442. A large gear 443 (first gear) that meshes with the gear 441, a small gear 444 (second gear) that is fixed to the support shaft 442 and meshes with the driven gear 445, and a support frame 431 are fixedly equipped. And a driven gear 445 that rotates around the center line C.
The fixed gear 441 is a spur gear arranged around the center line C, and the large gear 443 meshes with the fixed gear 441 and rotates around the fixed gear 441 when the hook rotating table 130 rotates. It is designed to move around. That is, in the rotation interlocking unit 440, a planetary gear mechanism in which the fixed gear 441 is a sun gear and the large gear 443 is a planetary gear is configured.
Here, the fixed gear 441 and the large gear 443 have the same number of teeth, and the transmission ratio is set to 1: 1. The small gear 444 and the driven gear 445 have 1: 2 teeth, and half rotation is transmitted to the driven gear 445 in the opposite direction with respect to the rotation of the small gear 444.

When the hook rotation base 130 rotates in a certain direction, the large gear 443 rotates around the center line C together with the hook rotation base 130 so as to be equal to the rotation angle of the hook rotation base 130. In addition, since the change with the fixed gear 441 causes an angle change around the support shaft 442 with respect to the rotary table 130, the rotary angle is equal to the rotary angle of the rotary table 130. This produces a double angle change in the same direction as 130.
On the other hand, the small gear 444 is equal to the rotation angle of the rotary table 130 by rotating around the center line C together with the rotary table 130 when the rotary table 130 rotates in a certain direction. In addition, an angle change is generated, and an angle change equal to the rotation angle of the rotary table 130 is generated around the support shaft 442 with respect to the rotary table 130 in conjunction with the large gear 443. A double angle change occurs in the same direction as the turntable 130.

On the other hand, when the small gear 444 moves around by the rotation of the rotary table 130, the driven gear 445 changes in the same direction as the rotary table 130 and has the same angular change. However, since the small gear 444 rotates around the support shaft 442 along with the rotation generated when the large gear 443 meshes with the fixed gear 441, the shuttle rotation table is rotated in the opposite direction to the shuttle rotation table 130 according to the transmission ratio. A rotation of half of the 130 rotation angle occurs. As a result, the driven gear 445 rotates in half the rotation angle of the rotary table 130 in the same direction as the rotary table 130.
That is, when the rotary table 130 is rotated by the rotation interlocking unit 440, the rotation angle of the rotary table 130 is half of the rotation angle of the rotary table 130 in the same direction as the rotary table 130 with respect to the support frame 431. The rotation operation is performed in conjunction with each other.

With the above configuration, the differential transmission mechanism 400 is driven via the differential mechanism unit 430 when rotation is input to the input shaft 411 in a constant direction at a constant rotational speed by driving the shuttle drive motor 401. Rotation is transmitted to the output shaft 412 at the same rotational speed in the opposite direction.
Further, when rotation is input to the rotary table 130 by a rotary rotation motor 402 at a fixed rotation angle in a fixed direction, the support frame 431 is rotated by the rotary interlocking unit 440. A rotation operation is transmitted in the same direction as the table 130 at a half rotation angle of the rotary table 130.
When the support frame 431 rotates at a half rotation angle of the rotary table 130, the differential mechanism 430 rotates the output shaft 412 in the same direction as the support frame 431 with respect to the input shaft 411. A rotational angle change that is twice the moving angle will occur.
That is, it is possible to give the output shaft 412 the same rotation angle change as the rotation angle of the rotary table 130 in the same direction as the rotary table 130 with respect to the input shaft 411. Therefore, when the shuttle turntable 130 is rotated, the output shaft 412 does not change in angle with respect to the shuttle turntable 130.
For this reason, even when the hook rotation base 130 is rotated in a state where the hook 801 of the hook mechanism 800 is rotationally driven on the hook rotation base 130, the output shaft 412 is not rotated by the rotation of the hook mechanism 800. Since the same angle change as that of the movement is given, even if the hook drive motor 401 is installed in a place where the rotation operation is not performed with respect to the hook mechanism 800 on the hook rotation base 130 that performs the rotation operation, The structure is such that no phase difference occurs in the rotation operation input to the hook mechanism 800 on the hook rotating base 130 when the moving base 130 rotates.

The operation of the rotation interlocking unit 440 will be described with a simple example in which the rotation angle is specifically determined.
When the rotary table 130 rotates 180 degrees counterclockwise, the large gear 443 and the small gear 444 fixed to the support shaft 442 rotate 180 degrees counterclockwise around the center line C together with the rotary table 130. To do. Further, the fixed gear 441 causes the large gear 443 and the small gear 444 to rotate 180 degrees around the support shaft 442 counterclockwise.
When the small gear 444 rotates 180 degrees counterclockwise around the center line C together with the shuttle turntable 130, the driven gear 445 engaged with the small gear 444 rotates 180 degrees counterclockwise around the center line C. Rotate degrees.
When the small gear 444 rotates counterclockwise about the support shaft 442 by 180 degrees, the small gear 444 and the driven gear 445 have a 1: 2 number of teeth, and the driven gear 445 is rotated clockwise around the center line C. Rotate 90 degrees in the direction.
As a result, the driven gear 445 rotates 90 degrees in the counterclockwise direction, which is the total of 180 degrees in the counterclockwise direction and 90 degrees in the clockwise direction.
The driven gear 445 is fixed to the support frame 431, and the support frame 431 also rotates 90 degrees counterclockwise. When the support frame 431 is rotated 90 degrees counterclockwise, the second bevel gear 433 is rotated by the rotation of the transmission bevel gear 435 (90 degrees in its clockwise direction) and the rotation of the support frame 431 (90 in the counterclockwise direction). Rotate 180 degrees counterclockwise, which is the sum of degrees. Since the second bevel gear 433 is fixed to the output shaft 412, the output shaft 412 also rotates counterclockwise by 180 degrees.
As shown in FIG. 2, the output sprocket 416 fixed to the output shaft 412 and the input sprocket 822 of the shuttle mechanism 800 are bridged by a timing belt 417.
However, when the shuttle rotation base 130 rotates 180 degrees counterclockwise, the output shaft 412 also rotates 180 degrees counterclockwise. For this reason, since the input sprocket 822 does not rotate with the rotation of the rotary table 130, no phase difference occurs in the shuttle mechanism.

[Hook mechanism]
FIG. 10 is a plan view of the hook mechanism 800, and FIGS. 11 and 12 are perspective views as seen from a different direction from FIG. 7 in which a part of the structure of the hook mechanism 800 is omitted.
As shown in FIGS. 2, 7, 8, and 10 to 12, the shuttle mechanism 800 is mounted on the upper surface of the mounting plate 131 of the shuttle rotating base 130. The hook mechanism 800 is configured to apply a torque from the hook 801 as a horizontal hook composed of an outer hook 802 that continuously rotates in a fixed direction and an inner hook 803 that stores a bobbin, and torque from the differential transmission mechanism 400 to the outer hook 802. A torque transmission mechanism 810 for transmission, a hook base 804 that rotatably supports the outer hook 802 via the hook shaft 811, and a convex portion 803 a provided on the inner hook 803 are fitted in the hook base 804. The rotation stopper 805 that restricts the rotation of the inner hook 803 and the inner hook 803 that contacts the inner hook 803 at the same cycle as the vertical movement of the needle bar 12 to form a gap through which the upper thread comes off between the rotation stopper 805 and the convex portion 803a of the inner hook. Opener 806, an opener actuating portion 820 for actuating the opener 806, a knife mechanism 830 that is mounted on the pot base 804 and cuts the lower thread, and an oil supply mechanism that supplies lubricating oil to the inside of the pot base 804 And a 40.

[Hook mechanism: Hook]
The inner hook 803 of the hook 801 is a bottomed, generally cylindrical body having an open upper portion, and a shaft portion into which a bobbin is fitted is erected at the center of the inner bottom surface, and has a function of storing the bobbin. ing.
The outer hook 802 is also a substantially cylindrical body with a bottom opened and stores and holds the inner hook 803 therein. The outer hook 802 maintains a concentric state with the inner hook 803 and is rotatably coupled to the inner hook 803. A hook shaft 811 (described later) is fixedly mounted at the center of the bottom surface of the outer hook 802 in a suspended state. The shuttle shaft 811 is supported by the shuttle base 804 so as to be rotatable along the Z-axis direction, and the fixed base 804 is fixedly mounted on the upper surface of the mounting plate 131 of the shuttle turning base 130 by screwing.
The outer hook 802 receives torque from the hook shaft 811 in a fixed direction, and rotates at a speed twice that of the needle up-and-down movement. The sword tip provided in the outer hook 802 captures the upper thread from the sewing needle 11 at a rate of once every two rotations.

The outer hook 802 is attached to the outer periphery of the inner hook 803, and continuously rotates in a fixed direction around a vertical center line while being in sliding contact with the inner hook 803.
On the other hand, the inner hook 803 is provided with a convex portion 803a protruding upward on the outer peripheral upper portion so as not to rotate together with the outer hook 802, and the convex portion 803a is fitted to a detent 805 approaching both sides in the rotation direction. doing. Note that the fitting portion is not limited to the shape protruding like the convex portion 803a, and may be a concave shape, for example, and the rotation stopper 805 may be convex to be fitted.

[Hook mechanism: Opener operating part]
The opener operating portion 820 vertically penetrates the pot base 804 and is supported rotatably in a state parallel to the Z-axis direction, and an input sprocket 822 fixedly installed at the lower end of the opener shaft 821; At the upper end of the opener shaft 821, an eccentric shaft 823 provided at a position eccentric from the rotation center line of the opener shaft 821, a crank rod 824 having one end connected to the eccentric shaft 823, an opener 806 and a crank A pivot arm 825 coupled to the other end of the rod 824.

As described above, the input sprocket 822 receives torque from the output sprocket 416 of the differential transmission mechanism 400 via the timing belt 417. The input sprocket 822 has a smaller diameter than the output sprocket 416, and the rotation is increased so that the input sprocket 822 rotates at the same rotational speed as the vertical movement of the needle bar 12, and torque is input.
In addition, a tension roller (not shown) is provided near the input sprocket 822. The pot base 804 is fixedly mounted on the upper surface of the mounting plate 131 of the pot rotating table 130 by screwing through a long hole, and the position is adjusted by loosening the screw, thereby enabling the position adjustment of the pot 801. By adjusting the position of the hook 801, the tension roller is always pressed against the timing belt 417 so that the timing belt 417 stretched between the input sprocket 822 and the output sprocket 416 does not loosen, and tension is applied to the belt. Yes.

The rotating arm 825 is supported on the upper portion of the pot base 804 so as to be rotatable around the Z axis, and one end of the rotating arm 825 is connected to the other end of the crank rod 824. As described above, the crank rod 824 is connected at one end to the eccentric shaft 823 and is given a circular motion, so that the rotating arm 825 is rotated at the same cycle as the rotation of the opener shaft 821 at the other end. Can do.
Accordingly, the opener 806 fixedly attached to the rotating arm 825 also reciprocally rotates together with the rotating arm 825 at its tip. The opener 806 is brought into contact with a locking projection 803b extending outward in the radial direction from the outer peripheral upper portion of the inner hook 803 by the rotation operation, and the convex portion 803a of the inner hook 803 and the rotation stopper 805 are rotated when the outer hook 802 is rotated. The part where the thread is in close contact with each other is separated to allow the upper thread to pass through.

[Hook mechanism: Torque transmission mechanism]
The torque transmission mechanism 810 is fixedly attached to the hook shaft 811 as a hook rotating shaft fixedly provided at the center of the bottom surface of the outer hook 802, a main driving gear 812 fixedly provided in the middle of the opener shaft 821, and the hook shaft 811. And a driven gear 813.
The ratio of the number of teeth of the main driving gear 812 and the driven gear 813 is 2: 1, and rotation is transmitted from the opener shaft 821 to the shuttle shaft 811 at double speed. That is, the outer hook 802 of the hook 801 is rotated at a speed twice that of the number of times the sewing needle moves up and down.

  The torque transmission mechanism 810 employs a gear mechanism, but any kind of transmission mechanism capable of transmitting torque can be used. For example, a belt mechanism may be used. In that case, it is desirable to drive the shuttle drive motor 401 in the reverse rotation or use a gear mechanism by replacing the torque transmission between the output sprocket 416 and the input sprocket 822 with the timing belt 417.

[Hook mechanism: Lubrication mechanism]
13A is a horizontal cross-sectional view of the oil supply mechanism 840, and FIG. 13B is a vertical cross-sectional view of the oil supply mechanism 840.
The oil supply mechanism 840 includes an oil tank (not shown) for storing lubricating oil provided in the pot base 804, a rotating portion 841 formed at an intermediate position of the opener shaft 821, an inner periphery of the pot base 804, and a cutout of the rotating portion 841. A pump chamber 844 as an oil supply space formed by the portion 841a, oil seals 845 and 846 attached to the upper and lower portions of the pump chamber 844, an inlet 843 for lubricating oil communicating with the pump chamber 844, and a pump A lubricating oil discharge port 842 that communicates with the chamber 844 and a plunger 847 that reciprocates in contact with the outer periphery of the rotating portion 841 are provided, and a plunger pump type oil supply pump is configured by these.

The cutout portion 841a of the rotating portion 841 is formed in an elliptical shape by notching one side of the rotating portion 841. The introduction port 843 is connected to the oil tank via a tube. The discharge port 842 is connected to the shuttle shaft 811 and the shuttle race surface via a tube.
The opener shaft 821 rotates counterclockwise when viewed from above, and a negative pressure is generated at the introduction port 843. A suction force is generated by the negative pressure, and the lubricating oil is sucked from the oil tank. The lubricating oil sucked into the pump chamber supplies the lubricating oil to the hook shaft and the hook race surface by the rotation of the opener shaft 821 and the action of the plunger 847.
In this oil supply mechanism 840, a plunger pump is illustrated, but any type of pump that can use a rotational drive source may be used.

[Hook mechanism: Female mechanism]
The knife mechanism 830 includes a knife base 832 that fixes and holds the fixed knife 831, a moving knife 833 that cuts the upper thread and the lower thread in cooperation with the fixed knife 831, a knife holding arm 834 that holds the moving knife 833, Provided at the lower end of the female support shaft 835, a female support shaft 835 that allows the female support arm 834 to rotate about the Z-axis, an outer cam 836 that serves as a cam for applying rotational power to the female support arm 834. A knife driving arm 837 to which rotational power is input from the outer cam 836, an air cylinder 838 for driving a knife for switching connection and disconnection of power input from the outer cam 836 to the female driving arm 837, and an air cylinder A transmission arm 839 for transmitting the switching operation of 838.

The knife holding arm 834 reciprocally rotates above the hook 801, and the moving knife 833 and the fixed knife 831 cut the upper thread and the lower thread.
The power for reciprocating rotation of the knife holding arm 834 is input from the knife drive arm 837 through the knife support shaft 835.
The knife driving arm 837 holds a roller 837a at the rotation end thereof, and the roller 837a is brought into contact with the outer periphery of the outer cam 836 so that the rotation operation is input according to the outer shape of the outer cam 836. Is done.
The outer peripheral cam 836 is fixedly installed below the opener shaft 821 and rotates together with the opener shaft 821. A part of the outer periphery has a large distance from the center of rotation, and a rotating operation is imparted to the knife driving arm 837 from the portion via the roller 837a.
As described above, the knife mechanism 830 obtains the power of the thread trimming operation from the opener shaft 821.

  On the other hand, since the opener shaft 821 continuously rotates in a constant direction during sewing, the outer peripheral cam 836 also rotates continuously in the same manner. Therefore, the knife mechanism 830 controls the air cylinder 838 for driving the knife during sewing so that the roller 837a is retracted to the position where it does not contact the outer peripheral cam 836 via the transmission arm 839, and when sewing is completed. When the thread trimming is executed, the air cylinder 838 is operated to bring the roller 837a into contact with the outer peripheral cam 836, thereby performing the thread trimming.

[Sewing machine control system: control device]
FIG. 14 is a block diagram showing a control system of sewing machine 100. The sewing machine 100 includes a control device 110 as operation control means for controlling the operation of each unit and each member described above. The control device 110 includes a ROM 112 that stores a program for performing operation control during sewing, a RAM 113 that is a work area for arithmetic processing, and a nonvolatile data memory 114 that serves as storage means for storing sewing data. And a CPU 111 for executing a program in the ROM 112.

Further, the CPU 111 is connected to the sewing machine motor drive circuit 21a, the X-axis motor drive circuit 102e, the Y-axis motor drive circuit 102f, the shuttle drive motor drive circuit 401a, the shuttle rotation motor drive circuit 402a, and the needle rotation motor via an interface (not shown). It is connected to the drive circuit 32a, and is further connected to each of the sewing machine motor 21, the X-axis motor 102c, the Y-axis motor 102d, the shuttle drive motor 401, the shuttle rotation motor 402, and the needle rotation motor 32 through these. The drive of each motor 21, 102c, 102d, 401, 402, 32 is controlled.
The sewing machine motor 21 includes an encoder (not shown), and the detected angle is output to the CPU 111.
The motors 102c, 102d, 401, 402, and 32 are stepping motors or servo motors. These origin search means (not shown) are connected to the CPU 111, and the CPU 111 recognizes the origin position of each motor from the output. Can do.
Further, the CPU 111 is connected to a drive circuit 838b for switching opening and closing of the electromagnetic valve 838a for operating the knife driving air cylinder 838 of the shuttle mechanism 800 via the interface, and controls the electromagnetic valve 838a via the drive circuit 838b. Do.

The sewing data stored in the data memory 114 sequentially stores the operation amounts of the X-axis motor 102c and the Y-axis motor 102d for each stitch for sewing a predetermined sewing pattern. In this case, operation control for driving the X-axis motor 102c and the Y-axis motor 102d is performed for each needle.
In addition, the control device 110 performs synchronous control so that the sewing machine motor 21 and the shuttle drive motor 401 match the vertical movement cycle of the needle bar 12 and the rotation cycle of the shuttle 801 during sewing. For this reason, the sewing machine motor 21 and the shuttle drive motor 401 are each provided with an encoder (not shown).

[Hitch stitch avoidance control]
Further, the CPU 111 executes hitch stitch avoidance control along with execution of sewing control based on the sewing data. 15 shows a case where the direction of the reference line P (see FIG. 2) from the position of the center line C of the needle bar to the position of the rotation center line of the shuttle 801 is the reference (270 °) on the XY plane. FIG. 5 is an explanatory diagram showing a sewing direction in which a hitch stitch occurs in a hatched area H. That is, as shown in the drawing, when the needle is moved in the angle range of θ1 to θ2 with respect to the direction from the position of the needle bar center line C toward the shuttle 801, hitch stitches are generated. Since the direction in which such hitch stitch occurs varies depending on the type of hook and other various conditions, the numerical values of the angles θ1 and θ2 obtained by performing trial sewing or the like for each sewing machine may be specified. The values of θ1 and θ2 are registered in the data memory 114 in advance.
Then, the CPU 111 reads the operation amount of the X-axis motor 102c and the Y-axis motor 102d for each stitch of the sewing data at the time of sewing, calculates the sewing direction of the next needle movement from each operation amount, and the current hook 801 It is determined whether or not the sewing direction calculated based on the position is within an angle range of θ1 to θ2. When it is within the range, before the needle drop is performed, the needle rotation motor 32 and the hook rotation motor 402 are driven synchronously to an angle outside the angle range of θ1 to θ2, and the needle bar 12 and the hook base 804 are driven. Is rotated around the center line C. Further, when the sewing direction is outside the angle range of θ1 to θ2, the current rotational positions of the needle bar 12 and the hook base 804 are maintained.
By performing the hitch stitch avoidance control for all the stitches of the sewing data, it is possible to avoid the occurrence of hitch stitches in the entire sewing pattern.
That is, this control device 110 functions as a sewing control means.

FIG. 16 is a flowchart of the hitch stitch avoidance control. Based on this, hitch stitch avoidance control will be specifically described.
First, at the time of sewing, the CPU 111 reads the amount of movement in the X-axis direction and the Y-axis direction from the sewing data and reads the storage of the angle centered on the current center line C of the hook 801 (step S1).
Then, an angle θ0 in the sewing direction with respect to a reference line P connecting the position of the center line C and the center position of the shuttle 801 is calculated (step S3).
Further, the CPU 111 determines whether or not the calculated angle θ0 in the sewing direction is within the angle range of θ1 to θ2 (step S5).

If the angle is out of the angle range, the processing is terminated as it is, and the needle drop is performed. If the angle is within the angle range, it is determined in which direction the hook 801 should be rotated (step S7).
That is, it is determined whether or not the absolute value of θ1−θ0 is smaller than the absolute value of θ2−θ0. If the absolute value of θ1−θ0 is small, an angle α that becomes a margin is added to the value. The shuttle 801 and the needle bar 12 are rotated in the reverse direction (step S9).
When the absolute value of θ2-θ0 is small, the hook 801 and the needle bar 12 are rotated in the forward direction at an angle obtained by adding the margin angle α to the value (step S11).
Note that it is desirable that the angle α serving as a margin can be arbitrarily set, and the set value is stored in the data memory 114. This α is also an absolute value.
Further, the CPU 111 stores the angle around the center line of the hook 801 after the rotation for the next hitch stitch angle region determination.
And hitch stitch avoidance control is complete | finished. Such control is performed before the needle drop of each needle.
In the above control, it is possible to always grasp the angle of the hook 801 around the center line C by sequentially storing the control operation amount after searching the origin of the hook rotation motor 402. Alternatively, an angle sensor may be provided on the hook rotating base 130 or the needle bar rotating base 31, and the angle of the hook 801 may be acquired by detecting the angle sensor.

[Needle bar rotation control]
Further, the CPU 111 executes needle bar rotation control in accordance with the execution of sewing control based on the sewing data. Note that this needle bar rotation control is not performed simultaneously with the hitch stitch avoidance control, but is selectively performed by designating either one in advance.
FIG. 17 is an explanatory diagram showing an upper thread path in the sewing machine 100. The sewing machine 100 is inserted from the thread tension device 151 into the eye hole 111 of the sewing needle 11 through the balance 142, the first thread guide 152, the second thread guide 153, and the needle bar thread guide 154.
The upper yarn U is widely used as a Z-twisted yarn (a yarn twisted in a clockwise direction from one end of the yarn toward the other end). In the case of this Z-twisted upper yarn U, As shown in FIG. 18A, in the state where the sewing needle 11 is in contact with the right inner wall of the eye hole 111, untwisting due to the vertical movement of the balance 142 occurs, which adversely affects the seam. On the other hand, as shown in FIG. 18B, in the state where it is in contact with the left inner wall of the eye hole 111 of the sewing needle 11, the change in twist due to the vertical movement of the balance 142 is small, and untwisting hardly occurs.

Therefore, it is desirable to maintain the state of FIG. Since this change in state is determined by the direction in which the cloth feed is performed, in the needle bar rotation control, the operation amount of the X-axis motor 102c and the Y-axis motor 102d for each stitch of the sewing data for the next needle movement is read and the cloth is fed. The movement direction is calculated, and the needle bar is controlled to rotate in the direction corresponding to the movement direction of the cloth in the state shown in FIG.
As shown in FIG. 19, when the needle bar thread guide 154 is located on the right side with respect to the sewing needle 11, the upper thread U supplied from the needle bar thread guide 154 is the end of the needle 111 facing the front. Inserted from the side and reaches the fabric. Therefore, in this state, when the sewing direction is the left side (the movement direction of the fabric is the right side), the state shown in FIG. 18A occurs, and when the sewing direction is the right side (the movement direction of the fabric is the left side), 18 (B). In addition, the arrow of FIG. 19 has shown the cloth moving direction.
That is, the control device 110 controls the needle rotation motor 32 so that the needle bar thread guide 154 is in the direction in which the needle bar thread guide 154 is located downstream in the sewing direction (upstream side in the cloth movement direction) with respect to the sewing needle 11. I do. In other words, the needle bar 12 is rotated in the direction in which the needle bar thread guide 154 is positioned on the opposite side of the determined needle movement direction by 180 °. The needle bar 12 is rotated at a timing when the rotation is completed before the needle bar angle of about 60 ° (the top dead center of the needle bar is 0 °), which is the top dead center of the balance 142.
Thereby, the control apparatus 110 performs control as a “follow-up control unit”.

The needle bar turning operation can be performed in either the forward direction or the reverse direction (see FIG. 15), but the direction in which the direction of the next needle bar 12 is less than the direction of the previous needle bar 12 is selected. Is rotated. That is, the control device 110 executes control as a “selection control unit”.
Further, since the hook 801 also needs to be rotated in the same direction as the needle bar 12, the hook rotation motor 402 is controlled at the same timing as the needle rotation motor 32 so as to be equal to the rotation amount of the needle bar 12. That is, the control device 110 executes control as a “synchronization control unit”.

As shown in FIG. 17, the upper thread U has a constant path from the thread tensioner 151 to the second thread guide 153. Therefore, when the rotation amount of the needle bar 12 increases, the needle thread 12 is wound around the needle bar 12. As a result, the thread tension changes due to friction, and the formation state of the seam also changes.
Accordingly, when the needle bar rotation control is performed, if the cumulative rotation angle that is repeated exceeds a predetermined maximum rotation angle from a predetermined reference position, the above-described forward / reverse selection by the selection control unit is performed. Regardless of the selection of the rotation direction, control is performed to select either the forward or reverse rotation direction so as not to exceed the maximum rotation angle. That is, the control device 110 executes control as a “regulation control unit”.
Here, the reference position is the direction in which the seam is formed in the direction of 0 ° in FIG. 18 described above (the direction in which the needle bar thread guide 154 is positioned in the direction of 180 °).
The maximum rotation angle is, for example, the direction in which the seam is formed in the direction of 270 ° (the direction in which the needle bar thread guide 154 is positioned in the direction of 90 °), but the friction between the upper thread U and the needle bar 12 Depending on the relationship, it may be increased or decreased.

FIG. 20 shows an operation example when the needle bar rotation control is executed according to the above example. In this figure, a case where square pattern sewing is performed is illustrated, and stitches are formed in the order of 0 °, 90 °, 180 °, and 270 °. In this figure, the solid line arrow indicates the sewing direction (the direction in which the seam is formed), and the broken line arrow indicates the cloth feeding direction (the movement direction of the cloth). The cloth feeding direction is the direction opposite to the sewing direction. It becomes.
The control device 110 reads the sewing data of this square pattern sewing, and if the initial sewing direction is calculated as 0 °, the cloth feed direction is 180 °, so that the needle bar thread guide 154 with respect to the needle bar 12 is obtained. Sewing is started with the direction (reference position) positioned in the 180 ° direction. Although the sewing direction is constant for each side, the control device 110 calculates the sewing direction for each needle and determines the direction of the needle bar 12.
When the next needle movement direction is 90 °, the cloth feed direction is 270 °, so that the needle bar thread guide 154 is positioned in the direction of 270 ° with respect to the needle bar 12. The rotation is performed so that Since the rotation direction at this time is 90 ° in the forward direction and 270 ° in the reverse direction, the forward direction is selected.
When the next corner is approached and the next needle movement direction is 180 °, the cloth feed direction is 0 °, so that the needle bar thread guide 154 is positioned in the direction of 0 ° with respect to the needle bar 12. Rotation is performed so as to be in a direction to perform. Since the rotation direction at this time is 90 ° for the forward direction and 270 ° for the reverse direction, the forward direction is selected.
When the next corner direction is 270 ° and the next needle movement direction is 270 °, the cloth feed direction is 90 °, so that the needle bar thread guide 154 is positioned in the 90 ° direction with respect to the needle bar 12. Rotation is performed so as to be in a direction to perform.
The rotation direction at this time is 90 ° in the forward direction and 270 ° in the reverse direction.However, when the rotation is performed in the forward direction, the cumulative maximum rotation angle from the reference position is 270 °. Therefore, rotation in the reverse direction is performed regardless of the control as the selection control unit. That is, since the rotation is performed at the 90 ° position in the reverse direction from the reference position, it is possible to prevent the entanglement of the upper thread U with respect to the needle bar 12.

  FIG. 21 is a flowchart of the needle bar rotation control. Based on this, the needle bar rotation control will be specifically described. In the following description, the direction of the needle bar 12 indicates the direction in which the needle bar thread guide 154 is located around the needle bar 12. As described above, an object is to control the needle bar so that the direction of the needle bar coincides with the sewing direction.

First, at the time of sewing, the CPU 111 reads the movement amount in the X-axis direction and the Y-axis direction from the sewing data, the current position θn that is the current needle bar direction, and the total rotation angle of the needle bar 12 so far. A certain cumulative angle θa is read (step S21).
Then, a sewing direction θ0 (target position) with respect to a reference line P connecting the position of the center line C and the center position of the shuttle 801 is calculated (step S23).
Further, the CPU 111 determines whether the rotation from the current position θn, which is the direction of the needle bar 12 immediately before the rotation, to the sewing direction θ0 has a smaller rotation angle amount in the forward rotation than in the reverse rotation. Determination is made (step S25).

When the amount of rotation angle is smaller in the positive direction, when the rotation angle in the positive direction is added from the current position θn to the sewing direction θ0 to the cumulative angle θa so far, the maximum value is 270 ° or more. It is determined whether or not (step S27).
If not exceeded, a forward turning operation is performed in the sewing direction θ0 from the current position θn (step S29).
When exceeding, the rotation operation in the reverse direction from the current position θn to the sewing direction θ0 is performed (step S31).

If it is determined in step S25 that the rotation from the current position θn to the sewing direction θ0 is smaller in the reverse direction than in the forward direction, the CPU 111 further When the reverse rotation angle from the current position θn to the sewing direction θ0 is added to the cumulative angle θa so far, it is determined whether or not the angle is further on the reverse side than the maximum value of −270 ° (Step S33).
If the angle does not become further in the reverse direction than -270 °, a reverse rotation operation is performed from the current position θn to the sewing direction θ0 (step S35).
When the angle is further on the opposite side than -270 °, the forward rotation is performed from the current position θn to the sewing direction θ0 (step S37).

After each of the needle bars 12 is rotated, the cumulative angle θa is updated in addition to the operation amount. Further, the current position θn is updated to the angle of the sewing direction θ0 (step S39).
Then, the processing for one stitch is finished.

[Effects of Embodiment]
The sewing machine 100 supports the needle bar 12 that holds the sewing needle 11 and the needle bar 12 so that the needle bar 12 can be moved up and down, and is rotated around a predetermined center line C parallel to the needle bar 12 together with the needle bar 12 by the sewing machine frame 101. The needle bar turning base 31 is connected to the needle bar 12 so as to be supported, and the needle up-and-down moving mechanism 20 that gives the needle bar 12 an up-and-down movement operation. The needle bar rotary base 31 includes a rotary motor 32 and a balance 142 for pulling up the upper thread U. The needle bar rotary base 31 supports a part of the upper end portion of the needle bar 12 so as to be movable up and down. Is connected to a portion supported by the needle bar 12 by the needle bar rotating base 31 so as to be able to rotate at another position below.
More specifically, the needle bar rotation base 31 supports the upper part of the needle bar 12 so as to be movable up and down, and the needle vertical movement mechanism 20 rotates to the needle bar 12 below the needle bar rotation base 31. Connected as possible.

Thus, the needle bar rotating base 31 supports a part of the upper end side of the needle bar 12, and the needle up-and-down moving mechanism 20 is connected to the needle bar 12 at another position where it does not overlap with the needle bar rotating base 31. Therefore, for example, the needle bar rotating table supports the upper and lower ends of the needle bar so as to be rotatable, and the needle bar and the needle up-and-down moving mechanism are connected between the support positions of the needle bar rotating table. Compared to the structure, the needle bar rotation base can be downsized in the vertical direction, and this can reduce the weight, facilitating high-speed rotation operation and increasing the sewing speed. .
Thereby, the needle bar turning operation in the hitch stitch avoidance control can also be performed at high speed, and it is possible to perform high-quality sewing without a hitch stitch at high speed.
In addition, the needle bar rotation operation in the needle bar rotation control can be performed at high speed, and high-quality sewing can be performed at high speed without causing thread untwisting.
Even when the needle bar rotating base 31 is downsized in the vertical direction, both the upper end and the lower end thereof are supported by the metal bearings 311 and 312 fixedly mounted on the sewing machine arm portion 101a, and the needle bar 12 is Since the upper and lower portions are supported by the bar metal bearings 121 and 122, the needle bar 12 can be firmly maintained in the state parallel to the Z-axis direction, and good needle vertical movement can be performed.

Further, the sewing machine 100 has a pair of convex portions 123a and 123b in which the needle bar 12 projects toward both outer sides in the diametrical direction with the needle bar 12 as the center, and the needle bar rotating base 31 is a convex portion. Two guide holes 314a and 314a are provided along the vertical direction in which 123a and 123b fit and slide.
Thereby, the followability of the rotation operation of the needle bar 12 with respect to the needle bar rotation base 31 can be improved, and a favorable rotation operation can be performed. Furthermore, with the above structure, the needle bar 12 can be well moved up and down with respect to the needle bar rotating base 31, and high-speed sewing can be stably performed.

The sewing machine 100 also has a hook 801 that catches the upper thread U and entangles the upper thread U with the lower thread by a rotation operation, and a hook 801, and is mounted around the same center line C as the needle bar 12 with respect to the sewing machine frame 101. A hook rotation base 130 that is rotatably supported, and a hook rotation motor 402 that is a drive source for the rotation operation of the hook rotation base 130, and the needle bar rotation base 31 and the hook rotation base 130. A control device 110 is provided as a synchronization control unit that controls the needle rotation motor 32 and the shuttle rotation motor 402 so that the respective rotation angles coincide with each other.
As described above, when the hook 801 is configured to be rotatable, the hook 801 is also rotated when the needle bar 12 is rotated, so that the hook 801 is smoothly raised from the sewing needle 12 whose direction is changed. The thread can be captured and the sewing operation can be performed reliably and smoothly.

Further, the sewing machine 100 has a cloth movement mechanism 120 as a movement mechanism capable of moving the sewing object in an arbitrary direction on a plane perpendicular to the rotation center line C (on a horizontal plane along the X direction and the Y direction). And the needle rotation motor 32 is controlled so that the needle bar 12 rotates following in the direction corresponding to the movement direction of the sewing object when the cloth movement mechanism 120 moves the sewing object. A control device 110 is provided as a follow-up control unit.
By performing such follow-up rotation control of the needle bar 12, when the upper thread U is pulled up by the balance 142, untwisting occurs due to the sliding of the upper thread U pulled out from the eye hole 111 of the sewing needle 11. It is possible to reduce the thread fraying state and the unwinding state, and it is possible to perform better sewing.

The sewing machine 100 also has a target position corresponding to the cloth movement direction when the control device 110 determines a fixed reference position (for example, 0 °) for the rotation angle of the needle bar 12 and rotates the needle bar 12. The control as a selection control unit that selects either the forward or reverse rotation direction so that the rotation angle amount from the rotation angle at which the current position becomes the current rotation angle decreases, and a plurality of rotation operations. When the total rotation angle exceeds a predetermined maximum rotation angle (for example, ± 270 °) from the reference position, the forward / reverse rotation direction is selected based on the control as the selection control unit. First, the control is performed as a restriction control unit that selects either the forward or reverse rotation direction that does not exceed the maximum rotation angle.
In the above embodiment, the maximum rotation angle is ± 270 °, but within a range where the upper thread U is not entangled with the needle bar 12 such as ± 330 ° ± 200 °, such as a range of ± 180 ° to ± 360 °. Various settings are possible.

Since a small rotation angle is selected by the control as the selection control unit, the speed of the rotation operation can be increased.
On the other hand, if the rotation angle of the needle bar 12 from the reference position increases as a result of repeated rotations of the needle bar 12, the supplied upper thread U may be entangled with the needle bar 12. Since the control as the restriction control unit is performed so as not to exceed the maximum rotation angle, the problem of entanglement can be solved and a satisfactory sewing operation can be performed.

  Further, before the control device 110 moves the sewing product by the cloth moving mechanism 102, the movement direction of the sewing product is out of the range when the predetermined hitch stitch generation range is included. In addition, by performing hitch stitch avoidance control for driving the hook rotation motor 402 to rotate the hook base 804 and the needle bar 12 around the center line C, the occurrence of hitch stitches can be effectively avoided. By realizing perfect stitching over the entire sewing, it is possible to dramatically improve the sewing quality.

[Second Embodiment]
As a second embodiment of the present invention, a sewing machine 100A that uses a female needle forming a unique needle drop hole as a sewing needle will be described with reference to FIGS.
FIG. 22 is an explanatory diagram showing an upper thread path in the sewing machine 100A. This sewing machine 100A is different from the above-described sewing machine 100 in that the lower end portion of the needle bar 12 is provided with a female needle 11A having a flat tip and a needle bar thread guide 154A for the female needle. Further, the control device 110 (see FIG. 14) of the sewing machine 100A performs a sewing operation control specific to the knife needle 11A described later.
The other configuration of the sewing machine 100A is the same as that of the sewing machine 100. In the following description, the difference between the sewing machine 100A and the sewing machine 100 will be mainly described.

The sewing machine 100A is a sewing machine that is suitable for performing so-called saddle (serie) stitch-like sewing with a female needle 11A on a sewing product made of leather or the like.
The saddle stitch is a sewing method in which a knife hole is opened in advance with a knife and two threads are alternately sewed in the opposite direction by hand sewing. The saddle stitch-like stitch formed by the sewing machine 100A has an appearance. This is the seam of the main sewing machine that approximates the original saddle stitch.
This sewing machine 100A has a thread path of the upper thread U from the thread tensioner 151 to the eye hole 111A of the female needle 11A through the balance 142, the first thread guide 152, the second thread guide 153, and the needle bar thread guide 154A. doing.
Further, as shown in FIGS. 23 and 24, a needle bar thread guide 154A is fixedly installed at the lower end of the needle bar 12, and when the needle bar 12 is rotated, the female needle 11A and the needle bar thread guide 154A are provided. And rotate around the center line C.
Further, the needle bar thread guide 154A is provided with a semi-arc-shaped upper thread guide hole centered on the center line C, and the upper thread U extending from the needle bar thread guide 154A to the female needle 11A even when the needle bar 12 is rotated. Can be suitably guided.
Note that the direction of the knife needle 11A (the rotation angle around the center line C) when the needle thread guide hole of the needle bar thread guide 154A is located on the balance 14 side with respect to the center line C is the reference position of the knife needle 11A. To do. That is, FIG. 23 and FIG. 24 show a state in which the knife needle 11A is at the reference position.

[Structure of knife needle]
25A is a front view of the female needle 11A at the reference position, FIG. 25B is a side view of the female needle 11A at the reference position, and FIG. 26 is a plan view of the female needle 11A at the reference position. Yes.
The scalpel needle 11A is a flat scalpel type scalpel needle whose tip 112A is flat and sharp. Then, as shown in FIG. 26, the eye hole 111A is in a state along the Y-axis direction while the knife needle 11A is at the reference position, and the flat tip portion 112A is in a state along the X-axis direction.
Thus, the scalpel needle 11A in which the tip 112A is orthogonal to the eye hole 111A is referred to as a horizontal scalpel.
Further, in the state where the knife needle 11A is in the reference position, one end portion of the eye hole 111A faces the operator side (the operator is located in front of the sewing machine surface portion), and the other end portion of the eye hole 111A is flat. It has been beaten. If the one end side of the eye hole 111A is the front side 113A and the other end side of the eye hole 111A is the counter side 114A, the upper thread U passed through the upper thread guide hole of the needle bar thread guide 154A is the female needle 11A. Is inserted from the front side 113A of the eye hole 111A toward the counterboring side 114A.
A hook 801 is disposed on the leading side 114A with respect to the knife needle 11A, and the hook 801 captures the upper thread loop from the leading side 114A of the knife needle 11A.

[Sewing control for saddle stitch style sewing]
Next, a description will be given of the sewing control performed by the control device 110 when saddle stitch-style sewing is performed according to a rectangular sewing pattern along the outer edge of the rectangular workpiece shown in FIG.
27, when the direction from the knife needle 11A toward the balance 142 is 0 °, the stitches are formed in the order of 0 °, 90 °, 180 °, 270 °, and 360 °. Is done. In FIG. 27, the solid line arrow indicates the sewing direction (the direction in which the seam is formed), and the broken line arrow indicates the cloth feeding direction (the cloth moving direction). The cloth feeding direction is opposite to the sewing direction. Direction.

[Sewing pattern]
That is, the sewing data in the data memory 114 of the control device 110 includes movement amount data for each stitch for the cloth movement mechanism 102 to move the sewing object in the following order (1) to (5). It has been established.
(1) Move the workpiece in the direction of 180 ° from the sewing start position S by a distance of 1/2 the long side of the rectangular sewing pattern.
(2) Move the workpiece in the direction of 270 ° by the short side distance of the rectangular sewing pattern.
(3) Move the workpiece in the direction of 0 ° by the distance of the long side of the rectangular sewing pattern.
(4) Move the workpiece in the direction of 90 ° by the short side distance of the rectangular sewing pattern.
(5) Move the workpiece in the direction of 180 ° by a distance of 1/2 the long side of the rectangular sewing pattern.

Here, FIGS. 28 and 31 show the case where the knife needle 11A is attached to the sewing machine 100A having the needle bar rotating mechanism and the hook rotating base, and the seam is formed by saddle stitch style sewing. Further, FIG. 29 shows an inappropriate stitch formed by saddle stitch-like sewing in which a needle needle 11A is mounted on a conventional sewing machine that does not include a needle bar rotating mechanism and a hook rotating base, and a similar seam is formed. An example of this is shown in FIG.
The seam by saddle stitch style sewing shown in FIG. 28 is formed with the inclination angle of the substantially slot-shaped needle drop hole h formed by the female needle 11A with respect to the seam forming direction F being maintained, and the knot of the upper thread U is maintained. Uk is formed such that the sewing start end portion Uk1 extends over the front end portion h1 of the needle drop hole h, and the sewing end end portion Uk2 extends over the rear end portion h2 of the next needle drop hole h.
Further, the seam by saddle stitch style sewing shown in FIG. 31 starts sewing from the upper left side, rotates the female needle 11A by 90 ° at the first needle drop point at the upper right side where the sewing direction bends at a right angle, A stitch-like seam is formed.
As shown in FIG. 29, according to the cloth moving mechanism of the conventional sewing machine that does not include the needle bar rotating mechanism and the shuttle rotating table, the needle drop hole h formed by the female needle 11A is only in a certain direction. It is only formed. For this reason, a conventional sewing machine that does not include a needle bar turning mechanism cannot form a seam by saddle stitch sewing as shown in FIG.

Further, as shown in FIG. 30, in the saddle stitch style sewing, there is a case where a seam assumed for the needle drop hole h is not formed. At the time of improper sewing in this sewing, the inclination angle of the substantially slot-like needle drop hole h formed by the female needle 11A with respect to the stitch formation direction F is formed while maintaining a constant state, but the knot Uk of the upper thread U is maintained. Is formed such that the sewing start end portion Uk1 extends to the rear end portion h2 of the needle drop hole h and the sewing end end portion Uk2 extends to the front end portion h1 of the next needle drop hole h.
The factors causing the inappropriate sewing are the rotation angle of the knife needle 11A, the path state of the upper thread U from the second thread guide 153 through the needle bar thread guide 154A through the eye hole 111A of the knife needle 11A, It is considered that the stitch formation direction is related.
On the other hand, as shown in FIG. 31, the needle drop hole h of the female needle 11A has a shape that is symmetric about the center line c1. For this reason, when the inclination angle of the needle drop hole h with respect to the stitch formation direction F is α °, the needle bar rotation angle around the center line C can be selected from two types of α ° and α ± 180 ° (+ : Clockwise direction,-: counterclockwise direction).
Therefore, with respect to a plurality of stitch forming directions defined in the sewing data, the needle bar rotation angles α ° and α ± 180 ° at which the needle drop holes h have a constant inclination angle with respect to each stitch forming direction are tested. By performing sewing or the like, one of the needle bar rotation angles at which proper sewing is performed is selected in advance, and the needle bar rotation angle is recorded in the sewing data.

If both α ° and α ± 180 ° can be sewn properly, any of them may be set in the sewing data, but within the range of ± 180 ° from the reference position of the knife needle 11A. It is desirable to select
If proper sewing is possible at α ± 180 °, select the one within α + 180 ° and α-180 ° that is within ± 180 ° from the reference position of the knife needle 11A. Is desirable.
When the needle bar rotation angle around the center line C is set in the sewing data, the needle bar rotation angle around the center line C may be determined for each stitch, but the sewing pattern shown in FIG. If the stitch formation direction F is constant for each of the sections (1) to (5) as shown above, the needle bar rotation angle around the center line C is set for each of the sections (1) to (5). May be.

A specific setting of the sewing data for performing saddle stitch sewing will be described with reference to the example of FIG.
This sewing data is based on the premise that saddle stitch sewing is performed in which the inclination angle of the needle drop hole h with respect to the stitch formation direction is + 45 °.
The direction on the balance 14 side with respect to the knife needle 11A is 0 °, and when the knife needle 11A is at the reference position (the needle bar thread guide 154 is on the balance 14 side), the rotation angle is 0 °.

In the sections (1) and (5), the stitch formation direction is 0 °, and the rotation angle of the knife needle 11A is + 45 ° (= α °).
In the section (2), the stitch formation direction is + 90 °, and the rotation angle of the knife needle 11A is -45 ° (= α-180 °).
In the section (3), the stitch formation direction is set to + 180 °, and the rotation angle of the knife needle 11A is set to + 45 ° (= α−180 °).
In the section (4), the seam forming direction is set to + 270 °, and the turning angle of the knife needle 11A is set to −45 ° (= α °).

In the section (1), the control device 110 controls the needle bar rotation motor 32 and the shuttle rotation motor 402 to set the knife needle 11A to a rotation angle of + 45 ° and to set the cloth movement mechanism 102 in the section (1) based on the sewing data. The stitch is formed in the direction of 0 ° from the sewing start position S by controlling.
In the section (2), the needle bar rotation motor 32 and the hook rotation motor 402 are controlled to set the knife needle 11A to a rotation angle of −45 °, and the cloth movement mechanism 102 is controlled to start from the end of the section (1). The seam is formed in the direction of + 90 °.
In the section (3), the needle bar rotating motor 32 and the hook rotating motor 402 are controlled to set the knife needle 11A to a rotation angle of + 45 °, and the cloth moving mechanism 102 is controlled to start from the end of the section (2). The seam is formed in the direction of + 180 °.
In the section (4), the needle bar turning motor 32 and the hook turning motor 402 are controlled to set the knife needle 11A to a turning angle of −45 °, and the cloth moving mechanism 102 is controlled to start from the end of the section (3). The seam is formed in the direction of + 270 °.
In the section (5), the needle bar rotation motor 32 and the hook rotation motor 402 are controlled to set the knife needle 11A to a rotation angle of + 45 °, and the cloth movement mechanism 102 is controlled to start from the end of the section (4). The seam is formed in the direction of 0 ° to the sewing start position S.
As a result, needle drop holes having an inclination angle of + 45 ° with respect to each side of the rectangular sewing pattern are formed at a constant pitch, and appropriate saddle stitch sewing shown in FIGS. 28 and 31 is performed. Is done.

[Other examples of flat knife type needles]
The flat knife-type knife needle is not limited to the knife needle 11A, in which the eye hole 111A and the tip 112A are orthogonal to each other. For example, in the female needle 11Aa shown in FIGS. 32 and 33, the positional relationship between the eye hole 111Aa, the counterboring part 114Aa, and the needle bar thread guide 154A is the same as that of the female needle 11A, but the flat tip part 112Aa is parallel to the eye hole 111Aa. (So-called vertical knife).
Further, the knife needle 11Ab shown in FIG. 34 and FIG. 35 has the same positional relationship between the eye hole 111Ab, the punching part 114Ab, and the needle bar thread guide 154A as the knife needle 11A, but the flat distal end part 112Ab is in relation to the eye hole 111Ab. It is formed in a direction inclined + 45 ° (so-called oblique knife).
36 and FIG. 37, the positional relationship between the eye hole 111Ac, the punching part 114Ac, and the needle bar thread guide 154A is the same as that of the female needle 11A, but the flat tip part 112Ac is not in the eye hole 111Ac. It is formed in a direction inclined by -45 ° (so-called oblique knife).

Even when the saddle stitch-style sewing described above is performed by these knife needles 11Aa to 11Ac, the same as the knife needle 11A.
For example, in the case of performing saddle stitch style sewing with the knife needle 11Aa for the sewing pattern of FIG. 31, when the needle bar thread guide 154A faces the balance 14 side, the sections (1) and (5) In the section (2), the rotation angle of the knife needle 11Aa is appropriately selected to be −45 ° or −45 ± 180 °, and in the section (2), the rotation angle of the knife needle 11Aa is appropriately selected to be + 45 ° or + 45 ± 180 °. In the section (3), the rotation angle of the knife needle 11Aa is appropriately selected as -45 ° or -45 ± 180 °. In the section (4), the rotation angle of the knife needle 11Aa is + 45 ° or + 45 ± 180 °. It is selected appropriately.

  In the case of performing saddle stitch style sewing with the knife needle 11Ab for the sewing pattern of FIG. 31, the rotation angle of the knife needle 11Ab is appropriately + 90 ° or + 90 ± 180 ° in the sections (1) and (5). In the section (2), the rotation angle of the knife needle 11Ab is appropriately selected as 0 ° or ± 180 °. In the section (3), the rotation angle of the knife needle 11Ab is + 90 ° or + 90 ± 180 °. In the section (4), the rotation angle of the knife needle 11Ab is appropriately selected as 0 ° or ± 180 °.

  In the case of performing saddle stitch style sewing with the knife needle 11Ac for the sewing pattern of FIG. 31, the rotation angle of the knife needle 11Ac is appropriately selected as 0 ° or ± 180 ° in the sections (1) and (5). In the section (2), the rotation angle of the knife needle 11Ac is appropriately selected as + 90 ° or + 90 ± 180 °, and in the section (3), the rotation angle of the knife needle 11Ac is appropriately selected as 0 ° or ± 180 °. In the section (4), the rotation angle of the knife needle 11Ac is appropriately selected as + 90 ° or + 90 ± 180 °.

[Other examples of knife needles other than flat knife type]
There are other types of scalpel needles having other pyramid shapes such as a triangular pyramid and a quadrangular pyramid, and these scalpel needles can also be used in the same manner as the sewing machine 100A.
When the shape of the tip of the scalpel needle is a regular n pyramid, the needle bar rotation angle capable of forming a needle drop hole having a constant inclination angle with respect to the sewing direction is α °, (α + 1 × (n / 360)) °, (α + 2 × (n / 360)) °, ..., (α + (n-1) × (n / 360)) ° The angle at which the sewing can be performed can be selected and set in the sewing data.

[Other examples of sewing patterns]
Further, as shown in FIG. 31, the sewing pattern may of course have different inclination angles of the needle drop holes with respect to the stitch formation direction F.
For example, as shown in FIG. 38, the needle drop hole h is orthogonal to the stitch formation direction F, and the knot Uk of the upper thread U is formed parallel to the stitch formation direction F, or as shown in FIG. The needle drop hole h may be formed parallel to the stitch formation direction F, and the knot Uk of the upper thread U may be formed parallel to the stitch formation direction F.

[Technical effects of the second embodiment]
As described above, the sewing machine 100A can obtain the same technical effects as the sewing machine 100 except for hitch stitch avoidance control and needle bar rotation control in the sewing machine 100.
Further, the sewing machine 100A is equipped with a female needle as a sewing needle, so that a needle drop hole can be formed in a direction corresponding to each sewing direction in a sewing pattern in which the sewing direction is changed. It is possible to perform an efficient saddle stitch sewing operation by simultaneous progress without separating the seam forming operation. Further, the sewing machine 100A can rotate the knife needle within a range of at least 360 °, and can form the inclination angle of the needle drop hole with respect to the stitch formation direction at an arbitrary angle without replacing the knife needle. Is possible.
Furthermore, when using a flat knife type female needle 11A (or female needles 11Aa to 11Ac), the needle drop hole when rotated by ± 180 ° and the tilt angle of the needle drop hole by a certain needle bar rotation angle The needle bar rotation angle for the predetermined sewing direction can be selected between the angle α ° and α ± 180 °, and more appropriate sewing can be realized. .

[Other examples of power transmission mechanisms]
In the above-described sewing machine 100, the case where the shuttle drive motor 401 of the power transmission mechanism 400 is fixedly mounted on the support frame 105 without being mounted on the shuttle turntable 130 is exemplified. The motor 401 may be mounted on the shuttle turntable 130.
Such a sewing machine 100C will be described with reference to FIGS. 40 is a cross-sectional view taken along the center line C and the YZ plane of the power transmission mechanism 400C and the shuttle mechanism 800 of the sewing machine 100C.
In the following description, only the difference between the sewing machine 100C and the sewing machine 100 will be described, and the same components will be denoted by the same reference numerals and redundant description will be omitted.
The sewing machine 100C is a so-called single needle sewing machine. Unlike the differential transmission mechanism 400 described above, the power transmission mechanism 400C of the sewing machine 100C does not include the differential mechanism section 430 including the support frame 431 and the rotation interlocking section 440, and the shuttle drive motor 401 is connected to the shuttle drive motor 401. It is directly mounted on the turntable 130. That is, this transmission mechanism 400C does not have a differential mechanism, but is a mere power transmission mechanism.

The shuttle drive motor 401 is fixedly held on the shuttle rotation base 130 with its output shaft disposed on the center line C and directed upward.
On the other hand, the rotational force transmission portion 410C of the power transmission mechanism 400C includes an output shaft 412C that is rotatably supported at a position on the center line C in the shuttle turntable 130, and an output sprocket that is fixedly mounted on the output shaft 412C. 416 and a timing belt 417 stretched between the output sprocket 416 and the input sprocket 822 of the shuttle mechanism 800, and the output shaft 412C of the rotational force transmitting portion 410C and the output shaft of the shuttle drive motor 401 Are connected by a coupling 419C.
The power transmission mechanism 400 </ b> C includes the same rotational power transmission unit 420 as the differential transmission mechanism 400, and rotates the shuttle rotation base 130 around the center line C together with the shuttle drive motor 401.
At the time of such rotation, the shuttle drive motor 401 rotates around its output shaft. Therefore, when the shuttle drive motor 401 rotates, the phase of the rotation transmitted from the output sprocket 416 to the input sprocket 822 of the shuttle mechanism 800 is determined. There is no change. Therefore, when the hook 801 is rotated, a phase shift does not occur, and the upper thread can be stably captured.

In addition, since the hook drive motor 401 is arranged on the center line C of the hook rotation base 130 and torque is inputted to the hook mechanism 800 on the mounting plate 131, the phase of the hook 801 is shifted when the hook mechanism 800 is rotated. Therefore, the differential mechanism portion 430 can be omitted, and the number of components can be reduced and the structure can be simplified.
On the other hand, since the hook drive motor 401 is mounted on the hook rotation base 130, there is a possibility that the weight of the whole hook drive base 130 may increase. However, in the power transmission mechanism 400C, the rotation center of the hook drive base 130 is increased. Since the output shaft of the hook drive motor 401 is located on the line C and the output shaft is arranged along the center line C, compared with the case where the motor is placed sideways or arranged away from the center line. The moment of inertia of the shuttle drive base 130 can be minimized, the output required for the shuttle rotation motor 402 can be reduced, and the motor can be downsized.
Further, the reduction of the moment of inertia makes it possible to increase the speed and accuracy of the turning operation.

In addition, when the hook drive motor 401 is mounted on the hook rotation base 130, the hook drive motor 401 must be pulled out of the hook rotation base 130, but the hook drive base does not cause twisting of the wiring. It is necessary to limit the range of the 130 rotation angles. In this case, the occurrence of a large twist can be avoided by setting the angle to about 360 ° or less, but sewing can be advanced in any direction as long as the rotation is possible within the range, and various sewing operations are possible. is there.

Further, a slip ring 106C may be mounted as shown in FIG. 40 without limiting the range of the rotation angle of the shuttle drive base 130.
The slip ring 106 </ b> C has a sliding contact inside, and maintains an electrical connection between an object that performs rotational movement and a non-rotating outside. The slip ring driving motor 401 mounted on the hook rotation base 130 is connected to the slip ring 106 </ b> C. By connecting with an external power source via the slip ring 106C, the rotation range of the rotary table 130 can be made unlimited.
In FIG. 40, the driven sprocket 422 of the rotational power transmission unit 420 is attached to the lower part of the rotary table 130 and the rotational force is applied from the lower part of the rotary table 130. Similarly, the driven sprocket 422 may be attached to the upper portion of the rotary table 130.

[Others]
The needle rotation motor 32 of the needle bar rotation mechanism 30 and the shuttle rotation motor 402 of the differential transmission mechanism 400 may be shared by a single motor. For example, the power of the shuttle rotation motor 402 is transmitted to the needle bar rotation base 31 by a known power transmission mechanism including a shaft, a gear mechanism, a belt mechanism, or a combination thereof arranged in the sewing machine frame 101 and rotated. It is good also as a structure made to do. Conversely, a configuration may be adopted in which the power of the needle rotation motor 32 is transmitted to the shuttle rotation base 130 side of the differential transmission mechanism 400 by a known power transmission mechanism. Specifically, the sewing machine frame 101 is provided with a rotating shaft along the Z-axis direction from the sewing machine arm portion 101a to the sewing machine bed portion 101b, and a single motor (needle rotating motor 32 or shuttle rotating motor) is provided on the rotating shaft. In 402), the rotational power is applied, and the main sprockets 33 and 421 may be provided on the rotary shaft, and the main sprockets 33 and 421 may be rotated from the rotary shaft via a belt mechanism or a gear mechanism. May be transmitted.

  Further, it is also possible to transmit torque from the sewing machine motor 21 to the input shaft 411 via a known power transmission mechanism so that the sewing machine motor 21 and the shuttle drive motor 401 are shared by one motor.

  Further, in the needle bar rotating base 31, the convex portions 123, 123 of the needle bar 12 are guided by the guide holes 314a, 314a penetrating to the outside, but the convex portion of the needle bar 12 is guided by the guide groove that does not penetrate to the outside. It is good also as a structure which guides 123,123.

  In the sewing machine 100 described above, the rotation of the needle bar is controlled as a restriction control unit, and the rotation angle of the shuttle 801 is controlled to be equal to that of the needle bar 12. As for the operation, it is sufficient that the hook 801 and the sewing needle 12 are in the same position, and there is no limit on the cumulative rotation angle amount, and the rotation angle amount in the forward and reverse street directions is controlled by the selection control unit. It is also possible to select only the one with less. This is because the lower thread does not cause the problem of tangling unlike the upper thread.

Further, in the control as the follow-up control unit, control is performed so that the direction of the needle bar 12 relative to the cloth movement direction is kept constant, but the mutual correspondence may not be 1: 1. good.
For example, the cloth movement direction 0 to 360 ° may be divided into a plurality of ranges, and the direction of the needle bar 12 may be set to a certain angle for each range. For example, when the cloth movement direction is set to six ranges every 60 °, and the cloth movement direction of the next needle movement belongs to any one of the ranges, the needle bar 12 is rotated in a fixed direction determined for the range. You may control as follows.
That is, if the needle bar 12 is oriented within a certain range of angle relative to the cloth movement direction, it is possible to sufficiently prevent the upper thread U from being twisted back.

11 Sewing needles 11A, 11Aa, 11Ab, 11Ac Female needle (sewing needle)
111 Needle hole 12 Needle bar 123 Convex part 20 Needle up / down movement mechanism 21 Sewing motor 30 Needle bar rotation mechanism 31 Needle bar rotation base 314 Guide plate 314a Guide hole 32 Needle rotation motors 100, 100A, 100C Sewing machine 101 Sewing machine frame 101a Sewing machine arm 102 Cloth moving mechanism (moving mechanism)
102a Holding frame 102c X-axis motor 102d Y-axis motor 103 Cloth placement plate (needle plate)
110 Control device (synchronous control unit, follow-up control unit, selection control unit, restriction control unit)
130 Pot rotation table 142 Balance 401 Pot drive motor 402 Pot rotation motor 800, 800B Pot mechanism 801 Pot C Center line

Claims (6)

A needle bar to hold the sewing needle;
A needle bar rotating base that supports the needle bar so as to be movable up and down, and is supported so as to be rotatable around the center line of the needle bar together with the needle bar;
A needle up-and-down movement mechanism coupled to the needle bar and imparting a vertical movement to the needle bar;
A needle rotation motor serving as a drive source for the rotation operation of the needle bar;
A scale for lifting the upper thread,
In a sewing machine comprising:
The needle bar rotating base supports a part of the needle bar so as to be movable up and down,
The sewing machine is characterized in that the needle up-and-down moving mechanism is connected so as to be rotatable at another position that does not overlap with a portion of the needle bar that is supported by the needle bar rotating base. The needle bar has a pair of convex portions protruding toward both outer sides in the diameter direction around the needle bar,
2. The sewing machine according to claim 1, wherein the needle bar rotation base includes two guide holes or guide grooves along a vertical direction in which the convex portions are fitted and slid. The needle bar turntable supports the upper part of the needle bar so as to be movable up and down,
The sewing machine according to claim 1 or 2, wherein the needle up-and-down moving mechanism is rotatably connected to the needle bar below the needle bar rotating base. A hook that catches the upper thread and entangles the upper thread with the lower thread by rotation;
A shuttle turntable mounted with the shuttle and supported so as to be rotatable about the same center line as the needle bar with respect to the sewing machine frame;
A hook rotation motor serving as a drive source for the rotation of the hook rotation table,
The synchronous control part which controls the said needle rotation motor and the hook rotation motor so that each rotation angle of the said needle bar rotation table and the said hook rotation table may correspond is provided. 4. The sewing machine according to any one of items 1 to 3. Provided with a moving mechanism that can move the workpiece in any direction on a horizontal plane,
A follow-up control unit that controls the needle rotation motor so that the needle bar rotates in a direction corresponding to the moving direction of the sewing product when the sewing mechanism is moved by the moving mechanism. The sewing machine according to any one of claims 1 to 4, further comprising: A fixed reference position is set for the rotation angle of the needle bar,
A selection control unit that selects either the forward or reverse rotation direction so that the rotation angle of the target position from the current position decreases when the needle bar is rotated;
When performing a plurality of rotation operations, if the total rotation angle exceeds a predetermined maximum rotation angle from the reference position, the maximum rotation angle is exceeded regardless of the selection by the selection control unit. The sewing machine according to claim 5, further comprising a restriction control unit that selects any one of forward and reverse rotation directions.

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