JP2019055108A - sewing machine - Google Patents

Abstract

To variously adjust the shape of a locus of a circulating operation of a feed dog.SOLUTION: A sewing machine 100 includes: a needle vertical movement mechanism; a sewing machine motor 16 which becomes the driving source; a feed dog 31; a horizontal feed mechanism 40 which obtains power from the sewing machine motor and transmits a reciprocating operation in a horizontal direction to the feed dog; a vertical feed mechanism 60 which imparts a reciprocating operation in a vertical direction to the feed dog; a feed adjusting body 55 which varies the amplitude of the reciprocating operation in the horizontal direction transmitted from the sewing machine motor to the feed dog by a rotation operation; a feed adjusting motor 57 which changes a rotation angle of the feed adjusting body so as to change and adjust a sewing pitch; and a control device 90 which controls the feed adjusting motor. The control device controls the feed adjusting motor during one cycle of the vertical movement of a needle bar and varies the rotation angle of the feed adjusting body a plurality of times, thereby performing control to change the shape of a locus of a circulating operation of the feed dog while maintaining a target sewing pitch.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a sewing machine that performs feed adjustment.

  In order to freely operate the feed dog, a horizontal feed mechanism that obtains power from the sewing motor and reciprocates in the horizontal direction of the feed dog with respect to the feed dog, and a vertical feed mechanism with respect to the feed dog that receives power from the sewing machine motor A vertical feed mechanism that reciprocates in the direction, a feed adjuster that varies the amplitude of the horizontal reciprocation that is transmitted from the sewing machine motor to the horizontal feed mechanism, and a rotation angle of the feed adjuster to change the sewing pitch. 2. Description of the Related Art A sewing machine including a feed adjustment motor that changes and adjusts has been conventionally used (see, for example, Patent Document 1).

JP 56-91790 A

  However, the above-mentioned conventional sewing machine can arbitrarily change the sewing pitch during sewing by controlling the feed adjusting motor, but cannot change and adjust the shape of the trajectory of the feed dog's circular movement in various ways. .

  An object of the present invention is to enable various changes and adjustments of the shape of the trajectory of the feed dog's circular motion.

The invention according to claim 1 is a sewing machine,
A needle up-and-down movement mechanism that moves the needle bar up and down;
A sewing machine motor as a drive source of the needle up-and-down movement mechanism;
A feed dog that feeds the material to be sewn on the needle plate;
A horizontal feed mechanism that obtains power from the sewing machine motor and transmits a reciprocating motion in the horizontal direction to the feed dog;
A vertical feed mechanism for applying a reciprocating motion in the vertical direction to the feed dog;
A feed adjuster that varies the amplitude of a horizontal reciprocating motion transmitted from the sewing machine motor to the feed dog by a turning motion;
A feed adjustment motor that changes and adjusts the sewing pitch by changing the rotation angle of the feed adjustment body;
In a sewing machine comprising a control device for controlling the feed adjustment motor,
The control device controls the feed adjustment motor during one cycle of the vertical movement of the needle bar to change the rotation angle of the feed adjustment body a plurality of times, thereby allowing the trajectory of the feed dog to rotate. Control for changing the shape is performed.

The invention according to claim 2 is the sewing machine according to claim 1,
The control device includes a first sewing pitch that is different in size between a passing point that is the highest position in the trajectory of the feed dog and at least one of two passing points that are the height of the needle plate upper surface. And the feed adjusting motor is controlled so that the rotation angle of the feed adjusting body becomes the second sewing pitch.

The invention according to claim 3 is the sewing machine according to claim 2,
The control device has a rotation angle of the feed adjusting body that becomes the first sewing pitch between a passing point that is the highest position and a passing point that is the lowest position in the trajectory of the feed dog's orbiting operation, The feed adjustment motor is controlled so that the rotation angle of the feed adjustment body becomes the second sewing pitch at the two passing points.

The invention according to claim 4 is the sewing machine according to claim 2,
The control device has a rotation angle of the feed adjusting body that becomes the first sewing pitch between a passing point that is the highest position and a passing point that is the lowest position in the trajectory of the feed dog's orbiting operation, The feed adjustment motor is controlled so that one of the two passing points becomes a rotation angle of the feed adjustment body that becomes the second sewing pitch.

The invention according to claim 5 is the sewing machine according to any one of claims 2 to 4,
The first sewing pitch is larger than the second sewing pitch.

The invention according to claim 6 is the sewing machine according to claim 1,
The control device includes: a passing point that is the highest position in the trajectory of the feed dog's orbiting operation; one of two passing points that are the needle plate upper surface height; and the other of the two passing points that are the needle plate upper surface height; Then, the feed adjusting motor is controlled so that the rotation angle of the feed adjusting body becomes the first to third sewing pitches having different sizes.

The invention according to claim 7 is the sewing machine according to claim 6,
The first sewing pitch is set to a value larger than the second sewing pitch, and the third sewing pitch is set to a value larger than the first sewing pitch.

  According to the present invention, the shape of the trajectory of the feed dog's orbiting operation can be changed and adjusted in various ways.

It is a perspective view which shows the main structures in the bed part of a sewing machine. It is a perspective view of a feed adjustment mechanism. It is a block diagram which shows the control system of a sewing machine. FIG. 4A is a diagram showing a change in the rotation angle around the support shaft of the feed adjusting body during one rotation of the sewing machine for realizing the shape of the trajectory of the reference shape, and FIG. 4B is a case where normal feeding is performed. FIG. 4C is a diagram showing the shape of the trajectory after the height adjustment. FIG. 5A is a view showing a change in the rotation angle around the support shaft of the feed adjusting body for realizing the shape of the deformation locus (1), and FIG. 5B is a view showing the shape of the deformation locus (1). It is. FIG. 6A is a view showing a change in the rotation angle around the support shaft of the feed adjusting body for realizing the shape of the deformation locus (2), and FIG. 6B is a view showing the shape of the deformation locus (2). It is. FIG. 7A is a diagram showing a rotation angle change around the support shaft of the feed adjusting body for realizing the shape of the deformation locus (3), and FIG. 7B is a diagram showing the shape of the deformation locus (3). It is. FIG. 8A is a view showing a change in the rotation angle around the support shaft of the feed adjusting body for realizing the shape of the deformation locus (4), and FIG. 8B is a view showing the shape of the deformation locus (4). It is. FIG. 9A is a view showing a change in the rotation angle around the support shaft of the feed adjusting body for realizing the shape of the deformation locus (5), and FIG. 9B is a view showing the shape of the deformation locus (5). It is. FIG. 10A shows the relationship between the feed dog and the presser foot pressure on the elliptical locus of the standard shape, and FIG. 10B shows the feed dog and presser foot presser on the rectangular locus of the deformation locus (1). It is explanatory drawing which shows the relationship of a pressure.

[Schematic Configuration of Embodiment]
Hereinafter, a sewing machine including a feed adjustment mechanism according to an embodiment of the present invention will be described in detail.
FIG. 1 is a perspective view showing a main configuration in the bed portion of the sewing machine 100.
As shown in FIG. 1, the sewing machine 100 includes a needle vertical movement mechanism (not shown) that moves the sewing needle up and down by rotating the upper shaft, a sewing machine motor 16 (see FIG. 3) that serves as a drive source for rotating the upper shaft, and an upper thread. Rotate the hook 12 around the lower thread, the cloth feed mechanism 30 that feeds the cloth to be sewn on the needle plate 11 in synchronization with the vertical movement of the sewing needle, and the upper shaft to the vertical feed shaft 33 of the cloth feed mechanism 30. A belt mechanism 20 that transmits force, a sewing machine frame (not shown) that supports each of the above components, and a control device 90 (see FIG. 3) that controls each of the above components are provided.
The sewing machine 100 is a so-called lockstitch sewing machine, and includes various components such as a balance mechanism, a thread tension, and a cloth presser that are included in a general lockstitch sewing machine.

The sewing machine frame includes a bed portion positioned at a lower portion of the entire sewing machine, a standing body portion erected upward at one end portion in the longitudinal direction of the bed portion, and an upper end portion of the standing body portion in the same direction as the bed portion. And an extended arm portion (not shown).
In the following description, the horizontal direction parallel to the longitudinal direction of the bed portion is defined as the Y-axis direction, the horizontal direction orthogonal to the Y-axis direction is defined as the X-axis direction, and the direction orthogonal to the X-axis and Y-axis directions. Is the Z-axis direction.

[Needle vertical movement mechanism and belt mechanism]
The needle up-and-down moving mechanism is disposed on the inner side of the arm portion, is rotationally driven by the sewing machine motor 16 and is disposed along the Y-axis direction, a needle bar that holds the sewing needle at the lower end portion, And a crank mechanism that converts the rotational force of the upper shaft into a reciprocating driving force that moves up and down and transmits it to the needle bar (all not shown).
The belt mechanism 20 includes a main pulley fixedly mounted on the upper shaft, a driven pulley 21 fixedly mounted on the vertical feed shaft 33 of the cloth feed mechanism 30, and a timing spanned between the main pulley and the driven pulley 21. Belt 22. Then, the belt mechanism 20 causes the vertical feed shaft 33 to fully rotate at the same speed as the upper shaft.
Instead of the belt mechanism 20, the rotational force may be transmitted from the upper shaft to the vertical feed shaft 33 by a gear transmission mechanism including a vertical axis along the Z-axis direction and a bevel gear.

[Cloth feed mechanism]
As shown in FIG. 1, the cloth feed mechanism 30 receives power from a feed dog 31 that moves in and out from the opening of the needle plate 11 to feed the fabric in a predetermined direction, a feed base 32 that holds the feed dog 31, and the sewing machine motor 16. The horizontal feed mechanism 40 that transmits the reciprocating motion in the X-axis direction (horizontal direction) to the feed base 32 and the vertical feed mechanism 60 that imparts the reciprocating motion in the vertical direction to the feed base 32 are provided. .

[Horizontal feed mechanism]
The horizontal feed mechanism 40 includes a feed adjusting mechanism 50 that adjusts the stroke of the reciprocating operation in the X-axis direction with respect to the feed base 32, a connecting rod 41 that takes out the reciprocating operation along the X-axis direction from the vertical feed shaft 33, and a feed adjusting mechanism. The horizontal feed shaft 42 to which reciprocating rotation is applied from the connecting rod 41 via 50, and the reciprocating rotational driving force of the horizontal feed shaft 42 are converted into reciprocating driving force in the feed direction (X-axis direction), thereby the feed base 32. And a horizontal feed arm 43 for transmitting to the head.

  One end of the connecting rod 41 rotatably holds an eccentric cam 44 fixedly mounted on the vertical feed shaft 33, and the other end is connected to the feed adjusting mechanism 50. The connecting rod 41 is arranged so that the longitudinal direction thereof is generally along the X-axis direction. When the vertical feed shaft 33 is driven at full rotation, the other end of the connecting rod 41 has two eccentric amounts of the eccentric cam 44. A reciprocating motion is performed along the longitudinal direction with a double stroke. The reciprocating motion of the connecting rod 41 is transmitted as reciprocating power to the horizontal feed shaft 42 via the feed adjusting mechanism 50.

[Feed adjustment mechanism]
As shown in FIGS. 1 and 2, the feed adjusting mechanism 50 is fixedly mounted on the horizontal feed shaft 42 and extends outward in the radial direction around the horizontal feed shaft 42, and a connecting rod. The reciprocating motion direction of the pair of first link bodies 53 that connect the other end of 41 and the swing arm 51 and the other end of the connecting rod 41 is guided in any direction along the XZ plane. A pair of second link bodies 54, a feed adjusting body 55 that determines the guiding direction by the second link body 54, a support shaft 52 that rotates integrally with the feed adjusting body 55, and a fixed attachment to the support shaft 52 The X-axis direction (horizontal direction) transmitted to the feed base 32 from the vertical feed shaft 33 by rotating the feed adjustment body 55 and the input arm 56 extended radially outward with the support shaft 52 as the center. ) Feed adjustment to adjust the amount of reciprocation A motor 57, and a two transmission links 58 and 59 for transmitting the input arm 56 twice the power from the output shaft of the feed adjusting motor 57.
Note that the positions of the horizontal feed shaft 42 and the vertical feed shaft 33 may be interchanged.

The first link body 53 has one end connected to the other end of the connecting rod 41 and the other end connected to the swing end of the swing arm 51, both of which rotate around the Y axis. It is linked movably.
One end portion of the second link body 54 is connected to the other end portion of the connecting rod 41 together with one end portion of the first link body 53, and the other end portion is connected to the rotating end portion of the feed adjusting body 55. Both end portions are connected so as to be rotatable about the Y axis.
The feed adjusting body 55 is fixedly equipped with a support shaft 52 along the Y-axis direction at the base end portion, and the support shaft 52 is supported so as to be rotatable around the Y-axis in the sewing machine frame.
Further, the rotation end portion of the feed adjusting body 55 is connected to the other end portion of the second link body 54 so as to be rotatable around the Y axis.

  In the feed adjusting mechanism 50, the feed adjusting body 55 is rotated so that the longitudinal directions of the first link body 53 and the second link body 54 coincide with each other, that is, the link bodies 53, 54 are just overlapped. When moved, the driving force of the connecting rod 41 is not transmitted to the swing arm 51. At this time, since the reciprocating rotation is not transmitted to the horizontal feed shaft 42, the reciprocating stroke of the feed base 32 in the X-axis direction is 0, that is, the sewing pitch is 0. In this way, the rotation angle of the feed adjusting body 55 in which the link bodies 53 and 54 overlap each other is referred to as a “neutral angle of the feed adjusting body 55”.

When the feed adjusting body 55 is rotated from the neutral angle to one side, a reciprocating swinging motion is applied to the swinging arm 51 in accordance with the amount of the pivoting angle, thereby increasing the sewing pitch in the forward feed direction. Can be bigger.
Further, when the feed adjusting body 55 is rotated in the reverse direction from the neutral angle, a reciprocating swinging operation can be imparted to the swinging arm 51 side according to the rotational angle amount. Is transmitted with the phase reversed, and thereby the sewing pitch in the reverse feed direction can be increased.

The feed adjustment motor 57 is arranged with the output shaft directed in the Y-axis direction on one end side in the Y-axis direction in the bed portion. One end of the transmission link 58 is fixed to the output shaft of the feed adjustment motor 57 with its longitudinal direction being substantially in the X-axis direction. Accordingly, the other end portion of the transmission link 58 rotates up and down by driving the feed adjusting motor 57.
The transmission link 59 has a lower end connected to the other end of the transmission link 58 so as to be rotatable about the Y axis in a state where the longitudinal direction thereof is substantially along the Z-axis direction. Accordingly, the transmission link 59 moves up and down as a whole by driving the feed adjusting motor 57.
The input arm 56 is fixedly mounted on the support shaft 52 and extends substantially along the X-axis direction from the support shaft 52, and its extended end rotates around the Y axis at the upper end of the transmission link 59. Connected as possible.
Accordingly, when the feed adjusting motor 57 is driven, the feed adjusting body 55 can be rotated via the transmission links 58 and 59 and the input arm 56.

  The horizontal feed shaft 42 is supported in the bed portion so as to be rotatable along the Y-axis direction, and is disposed on the downstream side in the fabric feed direction (left side in FIG. 1) with respect to the vertical feed shaft 33. A reciprocating power is applied from the vertical feed shaft 33 to the one end portion of the horizontal feed shaft 42 on the vertical trunk portion side via the feed adjusting mechanism 50 described above, and a horizontal feed arm 43 is provided from the other end portion of the horizontal feed shaft 42. The reciprocating motion along the X-axis direction is transmitted to the feed base 32 via the.

The horizontal feed arm 43 has a base end fixedly connected to an end of the horizontal feed shaft 42 on the throat plate 11 side, and a swinging end of the horizontal feed arm 43 can be rotated about the Y axis while being directed substantially upward. It is connected to the feed base 32.
Accordingly, the horizontal feed arm 43 can reciprocate the feed base 32 along the X-axis direction by driving the sewing machine motor 16. Further, the stroke of the reciprocating operation along the X-axis direction of the feed base 32 can be arbitrarily adjusted by controlling the feed adjustment motor 57 of the feed adjustment mechanism 50.

[Vertical feed mechanism]
As shown in FIG. 1, the vertical feed mechanism 60 includes a vertical feed shaft 33 that performs the above-described full rotation, a circular eccentric cam 61 that is fixedly installed at the end of the vertical feed shaft 33 on the needle plate 11 side, A connecting rod 62 that rotatably holds the eccentric cam 61 at one end is provided.

One end of the connecting rod 62 has the eccentric cam 61 as described above, and the other end is connected to one end of the feed base 32 in the X-axis direction so as to be rotatable about the Y-axis. Moreover, the other end part of the connecting rod 62 is extended upwards.
For this reason, when full rotation is applied to the vertical feed shaft 33, the reciprocating operation is performed along the vertical direction with a stroke twice the eccentric amount of the eccentric cam 61, and the reciprocating vertical motion is applied to the feed base 32. Can do.

[Feeding base]
The feed base 32 is disposed below the needle plate 11, one end in the cloth feed direction (X-axis direction) is connected to the connecting rod 62, and the other end is connected to the horizontal feed arm 43. Further, a feed dog 31 is fixedly installed at the upper part of the intermediate position in the longitudinal direction of the feed base 32.
Thus, the feed base 32 is given a reciprocating drive force in the vertical direction from one end thereof, and a reciprocating drive force in the feed direction is given from the other end in the same cycle. Then, by combining these reciprocating driving forces, a circular motion is performed by drawing an elliptical trajectory along the XZ plane. The feed dog 31 also performs an elliptical circular motion with the feed base 32, and the tip of the feed dog 31 moves upward from the opening of the needle plate 11 when moving in the upper region of the locus of the elliptical circular motion. Protrusions and fabrics can be sent.

[Sewing machine control system]
The control system of the sewing machine 100 is shown in the block diagram of FIG. As shown in FIG. 3, the sewing machine 100 includes a control device 90 that controls the operation of each component. The control device 90 is connected to a sewing machine motor 16 and a feed adjustment motor 57 via respective motor drive circuits 16a and 57a.
Further, the sewing machine motor 16 is provided with an encoder 161 for detecting the number of rotations thereof, and this encoder 161 is also connected to the control device 90 via a motor drive circuit 16a.

The control device 90 includes a CPU 91, a ROM 92, a RAM 93, and an EEPROM 94 (EEPROM is a registered trademark), and executes various operation controls to be described later. Instead of the EEPROM 94, a nonvolatile storage device such as a flash memory, EPROM, or HDD may be provided.
Further, an operation input unit 96 for inputting execution and setting of various operation controls for the cloth feed mechanism 30 described later is connected to the control device 90 via an interface 97.

[Operation control of cloth feed mechanism (reference pattern)
In the sewing machine 100, since the stroke of the reciprocating operation along the cloth feeding direction of the feed dog 31 can be arbitrarily changed by the feed adjusting motor 57, the feed adjusting motor 57 is driven a plurality of times during one rotation of the upper shaft. By performing the above, it is possible to variously change the shape of the trajectory of the orbiting operation of the feed dog 31.
FIG. 4B shows the shape of a reference-form trajectory when normal feeding is performed. In FIG. 4B, the horizontal axis indicates the position of the feed dog 31 in the X-axis direction, the vertical axis indicates the position of the feed dog 31 in the Z-axis direction, the left side of the horizontal axis is downstream in the feed direction, and the vertical axis is 0. The position is the height of the upper surface of the needle plate 11.
On the other hand, in FIG. 4A, the vertical axis indicates the rotation angle around the support shaft 52 of the feed adjusting body 55 for realizing the locus shape of FIG. 4B, and the horizontal axis indicates the feed dog 31. The phase angle is shown. Note that the circumference of the feed dog 31 is 360 °, and the position of the top dead center of the feed dog 31 is indicated as a start (0 °).
The rotation angle 360 ° of the feed dog 31 is synchronized with one cycle of the sewing needle.

When the feed dog 31 performs the revolving motion in the shape of the reference trajectory, as shown in FIG. 4A, the rotation angle of the feed adjusting body 55 is kept constant during one rotation of the upper shaft. doing.
In the following description, the sewing pitch in the shape of the reference-form trajectory is the first sewing pitch P1 (see FIG. 5A), and the feed adjustment is performed in which the feed dog 31 performs the revolving operation on the reference-form trajectory. The rotation angle of the body 55 is assumed to be θ1.
Further, when the rotation angle of the feed adjusting body 55 is made closer to the neutral angle, the stroke in the cloth feeding direction is shortened, and when it is away from the neutral angle, the stroke in the cloth feeding direction is lengthened.

In this reference-form trajectory, the ellipse is substantially symmetrical vertically with respect to the upper surface of the needle plate 11.
The control device 90 controls the feed adjustment motor 57 so that the rotation angle of the feed adjustment body 55 is maintained at θ1 during one rotation of the upper shaft of each needle when sewing is performed with a reference-form trajectory.

[Operation control of cloth feeding mechanism (deformation locus (1) locus pattern)]
In FIG. 5 (B), the solid line indicates the shape of the deformation locus (1) called box feed, and FIG. 5 (A) shows the feed adjuster for realizing the locus shape of FIG. 5 (B). The rotation angle of 55 around the support shaft 52 is shown.
The deformed locus (1) has a shape closer to a rectangle than the reference shape locus described above, and there is little change in the position of the feed dog 31 in the feed direction (X direction) when the feed dog 31 is rising and lowering, and the tip of the feed dog 31 Is small in height variation while protruding from the upper surface of the needle plate 11.
For example, when the attachment position of the feed dog 31 with respect to the feed base 32 is adjusted to be high, the trajectory of the reference ellipse is horizontally moved in the vertical axis direction as shown in FIG. (The two-dot chain line in the figure indicates the height of the center of the rotation locus of the feed dog 31). Therefore, between the time when the tip of the feed dog 31 protrudes from the upper surface of the needle plate to the feed dog phase 270 °, and between the time of the feed dog phase 90 ° and the time when the tip of the feed dog 31 descends to the lower surface of the needle plate, There arises a problem that the sewing pitch fluctuates due to a phenomenon called “feed back” in which the workpiece is fed in the direction opposite to the feed direction.
However, in the case of box feed as shown in the deformation locus (1), there is little change in the position in the feed direction (X direction) while the feed dog 31 is moving up and down, so feed back does not occur and Even if the attachment position of the feed dog 31 is changed, the sewing pitch hardly changes.
Further, as shown in FIG. 10A, in the case of the elliptical trajectory of the standard shape, the presser pressure by the cloth presser 17 when the feed dog 31 is rising and lowering tends to become unstable. In the case of the rectangular trajectory of the deformation trajectory (1), the pressing pressure by the cloth presser 17 while the feed dog 31 is in contact with the workpiece to be sent can be maintained almost constant, and the feed is accurately performed. Can be done.

In order to feed the feed dog 31 in the shape of the deformation locus (1), the rotation angle θ1 at which the feed adjusting body 55 becomes the first sewing pitch P1 and the second sewing pitch P2 during one rotation of the upper shaft The feed adjustment motor 57 is controlled so that the fluctuating operation is performed a plurality of times with respect to the rotation angle θ2. In FIG. 5B, the locus shape of the first sewing pitch P1 is exemplified by a one-dot chain line, and the locus shape in the case of the second sewing pitch P2 is exemplified by a two-dot chain line.
That is, the control device 90 has the first sewing pitch P1 (rotation angle θ1) at the passing point α that is the highest position and the passing point β that is the lowest position in the deformation locus (1), and the height of the needle plate upper surface. The feed adjustment motor 57 is controlled so as to change the rotation angle so that the second sewing pitch P2 (rotation angle θ2) is reached at the two passing points b and e.
The rotation angle θ1 is an angle farther from the neutral angle than the rotation angle θ2 (an angle for increasing the sewing pitch), the angle away from the neutral angle is large, and the angle approaching the neutral angle is small.

More specifically, the rotation angle of the feed adjusting body 55 is maintained at θ1 in the section of the passing point α-a in the deformation trajectory (1), and the rotation of the feed adjusting body 55 in the section of the passing point ab. The angle is gradually decreased from θ1 to θ2, and the rotation angle of the feed adjusting body 55 is gradually increased from θ2 to θ1 in the section of the passing point bc, and the feed adjustment is performed in the section of the passing point cd including the passing point β. The rotation angle of the body 55 is maintained at θ1, and the rotation angle of the feed adjustment body 55 is gradually decreased from θ1 to θ2 in the section of the passing point de, and the feed adjustment body 55 in the section of the passage point ef. Is gradually increased from θ2 to θ1, and the feed adjustment motor 57 is controlled so that the rotation angle of the feed adjustment body 55 is maintained at θ1 in the section of the passing point f−α.
That is, the rotation angle θ1 and θ2 of the feed adjusting body 55 is changed in two reciprocations during one rotation of the upper shaft.

The shape of the deformation locus (1) is that of the rotation angle of the feed adjusting body 55 between the rotation angle θ1 that becomes the first sewing pitch P1 and the rotation angle θ2 that becomes the second sewing pitch P2. The actual sewing pitch is the second sewing pitch P2, although this is realized by the variation.
Then, the EEPROM 94 of the control device 90 has various sizes of sewing while the feed dog is moved around in the shape of the deformation locus (1) so that the shape of the deformation locus (1) can be performed at an arbitrary sewing pitch. An appropriate combination of the first sewing pitch P1 and the second sewing pitch P2 is prepared for each of various sewing pitches to be sewn so that the feed can be performed at the pitch.
When the shape of the deformation locus (1) and the sewing pitch are selected from the operation input unit 96, the CPU 91 reads an appropriate combination of the first sewing pitch P1 and the second sewing pitch P2 from the EEPROM 94. Then, fluctuation control of the rotation angle of the feed adjusting body 55 is executed.

[Operation control of fabric feed mechanism (deformation locus (2) locus pattern)]
6B shows the shape of the deformation locus (2), and FIG. 6A shows the rotation angle around the support shaft 52 of the feed adjusting body 55 for realizing the locus shape of FIG. 6B. Yes.
In this deformation locus (2), the ascending section of the feed dog 31 of the feed dog 31 has the same oval shape as the reference locus, and the descending section has the same rectangular shape as the deformation locus (1).
If the feed dog 31 is fed along this locus, the feed dog 31 can be gradually held and fed to the sewing product in the first half of feeding, which is suitable for feeding a thin sewing product.

In order to feed the feed dog 31 in the shape of the deformation trajectory (2), the control device 90 has two passage points which are the highest and lowest positions in the deformation trajectory (2) of the feed dog 31 and the height of the needle plate upper surface. Feed adjustment motor so that one of the two passing points (passing point when lowered) has a first sewing pitch P1 (rotation angle θ1) and a second sewing pitch P2 (rotation angle θ2), respectively. Fluctuation control of the rotation angle of the feed adjusting body 55 by 57 is performed.
More specifically, during one rotation of the upper shaft, the rotation angle of the feed adjusting body 55 is gradually decreased from θ1 to θ2 while descending from the highest position of the feed dog 31 to the needle plate height, and from the needle plate height. The feed adjustment motor 55 gradually increases the rotation angle of the feed adjustment body 55 from θ2 to θ1 while descending to the lowest position, and maintains the rotation angle of the feed adjustment body 55 at θ1 from the lowest position to the highest position. 57 is controlled.
That is, the rotation angle θ1 and θ2 of the feed adjusting body 55 is changed in one reciprocation during one rotation of the upper shaft.

The shape of the deformation locus (2) is that of the rotation angle of the feed adjusting body 55 between the rotation angle θ1 that becomes the first sewing pitch P1 and the rotation angle θ2 that becomes the second sewing pitch P2. The actual sewing pitch is P1 × 1/2 + P2 × 1/2, although this is realized by variation.
Then, the EEPROM 94 of the control device 90 has various sizes of sewing while the feed dog is moved around in the shape of the deformation locus (2) so that the shape of the deformation locus (2) can be performed at an arbitrary sewing pitch. An appropriate combination of the first sewing pitch P1 and the second sewing pitch P2 is prepared for each of various sewing pitches to be sewn so that the feed can be performed at the pitch.
When the shape of the deformation trajectory (2) and the sewing pitch are selected from the operation input unit 96, the CPU 91 reads an appropriate combination of the first sewing pitch P1 and the second sewing pitch P2 from the EEPROM 94. Then, fluctuation control of the rotation angle of the feed adjusting body 55 is executed.

[Operation control of fabric feed mechanism (deformation locus (3) locus pattern)]
FIG. 7B shows the shape of the deformation trajectory (3), and FIG. 7A shows the rotation angle around the support shaft 52 of the feed adjusting body 55 for realizing the trajectory shape of FIG. 7B. Yes.
In this deformation trajectory (3), the ascending section of the feed dog 31 has the same rectangular shape as the deformation trajectory (1), and the descending section of the feed dog 31 has the same oval shape as the reference-form trajectory.
When the feed dog 31 is fed along this locus, the feed dog 31 is sufficiently pressed against the workpiece in the first half of feeding and gradually descends in the second half of feeding, so that the workpiece to be fed during feeding is held strongly and fed out. Suitable for feeding thick sewing products.

In order to feed the feed dog 31 in the shape of the deformation trajectory (3), the control device 90 has two passage points which are the highest and lowest positions in the deformation trajectory (3) of the feed dog 31 and the height of the needle plate upper surface. Feed adjustment motor so that one of the two passing points (passing point when ascending) has a first sewing pitch P1 (rotation angle θ1) and a second sewing pitch P2 (rotation angle θ2), respectively. 57 is controlled.
More specifically, the rotation angle of the adjusting body 55 is maintained at θ1 from the highest position to the lowest position of the feed dog 31 during one rotation of the upper shaft, and the feed adjustment is performed while the adjustment body 55 is raised from the lowest position to the needle plate height. The rotation angle of the body 55 is gradually reduced from θ1 to θ2, and the feed adjustment motor 57 is controlled so that the rotation angle of the feed adjustment body 55 gradually increases from θ2 to θ1 while rising from the needle plate height to the highest position. Do.
That is, the rotation angle θ1 and θ2 of the feed adjusting body 55 is changed in one reciprocation during one rotation of the upper shaft.

The shape of the deformation locus (3) is that of the rotation angle of the feed adjusting body 55 between the rotation angle θ1 that becomes the first sewing pitch P1 and the rotation angle θ2 that becomes the second sewing pitch P2. The actual sewing pitch is P1 × 1/2 + P2 × 1/2, although this is realized by variation.
Then, the EEPROM 94 of the control device 90 has various sizes of sewing while the feed dog is moved around in the shape of the deformation locus (3) so that the shape of the deformation locus (3) can be performed at an arbitrary sewing pitch. An appropriate combination of the first sewing pitch P1 and the second sewing pitch P2 is prepared for each of various sewing pitches to be sewn so that the feed can be performed at the pitch.
When the shape of the deformation locus (3) and the sewing pitch are selected from the operation input unit 96, the CPU 91 reads an appropriate combination of the first sewing pitch P1 and the second sewing pitch P2 from the EEPROM 94. Then, fluctuation control of the rotation angle of the feed adjusting body 55 is executed.

[Operation control of fabric feed mechanism (deformation locus (4) locus pattern)]
FIG. 8B shows the shape of the deformation locus (4), and FIG. 8A shows the rotation angle around the support shaft 52 of the feed adjusting body 55 for realizing the locus shape of FIG. 8B. Yes.
In this deformation locus (4), the ascending section of the feed dog 31 has an oval shape that is longer in the cloth feeding direction than the reference-form locus, and the descending section of the feed dog 31 has the same rectangular shape as the deformation locus (1). .
When the feed dog 31 is fed along this locus, the feed dog 31 can be gradually held and fed out by the workpiece in the first half of the feed, so that it is suitable for feeding a thin workpiece further than the deformation locus (2). Yes.

In order to feed the feed dog 31 in the shape of the deformation trajectory (4), the control device 90 has the highest and lowest passing points in the deformation trajectory (4) of the feed dog 31 and the needle plate upper surface height. One of the two passing points (passing point at the time of lowering) and the other one of the two passing points (the passing point at the time of ascent) of the needle plate upper surface height (passing point at the time of rising), respectively. The feed adjustment motor 57 is controlled so that the angle θ1), the second sewing pitch P2 (rotation angle θ2), and the third sewing pitch P3 (rotation angle θ3) are satisfied (however, θ2 <θ1 <θ3).
More specifically, during one rotation of the upper shaft, the rotation angle of the feed adjusting body 55 is gradually decreased from θ1 to θ2 while descending from the highest position of the feed dog 31 to the needle plate height, and from the needle plate height. The rotation angle of the feed adjustment body 55 is gradually increased from θ2 to θ1 while descending to the lowest position, and the rotation angle of the feed adjustment body 55 is gradually increased from θ1 to θ3 while being raised from the lowest position to the needle plate height. The feed adjustment motor 57 is controlled so that the rotation angle of the feed adjustment body 55 gradually decreases from θ3 to θ1 while the needle plate height rises from the needle plate height.
That is, during one rotation of the upper shaft, the reciprocation angle 55 of the feed adjustment body 55 is reciprocated between one rotation and the reciprocation between the rotation angles θ1 and θ3.

The shape of the deformation locus (4) includes a rotation angle θ1 that becomes the first sewing pitch P1, a rotation angle θ2 that becomes the second sewing pitch P2, and a rotation angle θ3 that becomes the third sewing pitch P3. However, the actual sewing pitch is P2 × 1/2 + P3 × 1/2.
Then, the EEPROM 94 of the control device 90 has various sizes of sewing while the feed dog is moved around in the shape of the deformation locus (4) so that the shape of the deformation locus (4) can be performed at an arbitrary sewing pitch. An appropriate combination of the first sewing pitch P1, the second sewing pitch P2, and the third sewing pitch P3 is prepared for each of various sewing pitches to be sewn so that the feed can be performed at the pitch.
When the shape of the deformation locus (4) and the sewing pitch are selected from the operation input unit 96, the CPU 91 selects the first sewing pitch P1, the second sewing pitch P2, and the third sewing pitch from the EEPROM 94. An appropriate combination of P3 is read out, and fluctuation control of the rotation angle of the feed adjusting body 55 is executed.

[Operation control of cloth feeding mechanism (deformation locus (5) locus pattern)]
FIG. 9B shows the shape of the deformation locus (5), and FIG. 9A shows the rotation angle around the support shaft 52 of the feed adjusting body 55 for realizing the locus shape of FIG. 9B. Yes.
In this deformation locus (5), the ascending section of the feed dog 31 has the same rectangular shape as the deformation locus (1), and the descending section of the feed dog 31 has an oval shape that is longer in the cloth feeding direction than the reference-form locus. .
When the feed dog 31 is fed along this trajectory, the feed dog 31 is sufficiently pressed against the sewing product in the first half of the feed, and gradually descends in the second half of the feed, so that the feed of the sewing material that is thinner than the deformation trajectory (3) Suitable for

In order to feed the feed dog 31 in the shape of the deformation trajectory (5), the control device 90 has two passing points which are the highest position and the lowest position in the deformation trajectory (5) of the feed dog 31 and the height of the needle plate upper surface. One of the two passing points (passing point at the time of lowering) and the other one of the two passing points (the passing point at the time of ascent) of the needle plate upper surface height (passing point at the time of rising), respectively. The feed adjustment motor 57 is controlled so that the angle θ1), the third sewing pitch P3 (rotation angle θ3), and the second sewing pitch P2 (rotation angle θ2) are satisfied (however, θ2 <θ1 <θ3).
More specifically, during one rotation of the upper shaft, the rotation angle of the feed adjusting body 55 is gradually increased from θ1 to θ3 while descending from the highest position of the feed dog 31 to the needle plate height, and from the needle plate height. The rotation angle of the feed adjustment body 55 is gradually decreased from θ3 to θ1 while descending to the lowest position, and the rotation angle of the feed adjustment body 55 is gradually decreased from θ1 to θ2 while it is elevated from the lowest position to the needle plate height, The feed adjusting motor 57 is controlled so that the rotation angle of the feed adjusting body 55 is gradually increased from θ2 to θ1 while it is raised from the needle plate height to the highest position.
That is, during one rotation of the upper shaft, the reciprocation angle 55 of the feed adjustment body 55 is reciprocated between one rotation and the reciprocation between the rotation angles θ1 and θ3.

The shape of the deformation locus (5) includes a rotation angle θ1 that becomes the first sewing pitch P1, a rotation angle θ2 that becomes the second sewing pitch P2, and a rotation angle θ3 that becomes the third sewing pitch P3. However, the actual sewing pitch is P2 × 1/2 + P3 × 1/2.
Then, the EEPROM 94 of the control device 90 has various sizes of sewing while moving the feed dog in the shape of the deformation locus (5) so that the shape of the deformation locus (5) can be performed at an arbitrary sewing pitch. An appropriate combination of the first sewing pitch P1, the second sewing pitch P2, and the third sewing pitch P3 is prepared for each of various sewing pitches to be sewn so that the feed can be performed at the pitch.
When the shape of the deformation locus (5) and the sewing pitch are selected from the operation input unit 96, the CPU 91 selects the first sewing pitch P1, the second sewing pitch P2, and the third sewing pitch from the EEPROM 94. An appropriate combination of P3 is read out, and fluctuation control of the rotation angle of the feed adjusting body 55 is executed.

[Effects of the Embodiment of the Invention]
As described above, the sewing machine 100 allows the control device 90 to change the rotation angle of the feed adjusting body 55 by the feed adjusting motor 57 during one cycle of the upper shaft synchronized with the vertical movement of the needle bar. The control is performed to change the shape of the trajectory of the feed dog 31 while maintaining the sewing pitch.
Thereby, the locus | trajectory of the rotation operation | movement of the feed dog 31 can be changed into various shapes, and it becomes possible to feed the feed dog 31 suitable for various sewing conditions.

  Further, the control device 90 performs the first stitching with different sizes at the passing point that is the highest position in the trajectory of the revolving motion of the feed dog 31 and one of the two passing points that is the height of the needle plate upper surface. By controlling the feed adjustment motor 57 so as to be the pitch P1 and the second sewing pitch P2, for example, the feed dog 31 can be fed in the shape of the deformation locus (2) and the deformation locus (3) described above, Sewing can be performed by cloth feeding according to each shape characteristic as described above.

  Further, the control device 90 has the first sewing pitch P1 between the passing point that is the highest position and the passing point that is the lowest position in the trajectory of the revolving motion of the feed dog 31, and the two passing points that are the needle plate upper surface height. Since the feed adjusting motor 57 is controlled so as to be the second sewing pitch P2, for example, the feed dog 31 can be fed in the shape of the deformation locus (1) described above, and the cloth feed according to the shape characteristic close to a rectangle Sewing can be performed with.

  Further, the control device 90 has the first sewing pitch P1 between the passing point which is the highest position and the passing point which is the lowest position in the trajectory of the revolving motion of the feed dog 31, and the two passing points which are the height of the needle plate upper surface. On the other hand, by controlling the feed adjustment motor 57 so as to be the second sewing pitch P2, for example, the feed dog 31 can be fed in the shape of the deformation locus (2) or the deformation locus (3) described above. Thus, it is possible to perform sewing by cloth feeding according to the respective shape characteristics.

  The control device 90 also includes a passing point that is the highest position in the trajectory of the feed dog 31, one of the two passing points that are the needle plate upper surface height, and the other of the two passing points that are the needle plate upper surface height. By controlling the feed adjustment motor 57 so that the first to third sewing pitches P1 to P3 are different in size, for example, the shape of the deformation trajectory (4) or the deformation trajectory (5) described above is obtained. Thus, the feed dog 31 can be fed, and sewing can be performed by cloth feed according to the respective shape characteristics as described above.

[Others]
In the above-described deformation trajectories (1) to (5), the feed adjustment is performed so that the first sewing pitch P1 is set at the passing point which is the highest position and the passing position which is the lowest position in the trajectory of the circular motion. Although the case where the motor 57 is controlled is illustrated, the passing point which is the lowest position may be different from the first sewing pitch P1. For example, the passing point which is the lowest position may be a value larger or smaller than the first sewing pitch P1.

Further, the vertical feed shaft 33 of the sewing machine may be configured to perform reciprocal rotation instead of full rotation. For example, an eccentric cam may be provided on the upper shaft, and the other end of the connecting rod holding the eccentric cam at one end may be connected to an arm fixed to the vertical feed shaft 33 to provide reciprocating rotation. In that case, the rotating arm extended along the X-axis direction from the vertical feed shaft 33 is connected to the feed base 32 to provide the vertical motion.
Further, the horizontal feed shaft 42 may be configured to be reciprocated from the upper shaft instead of the vertical feed shaft 33. In that case, it is desirable to equip the upper shaft with an eccentric cam on one end side of the connecting rod 41.

  Further, in the embodiment of the present invention, a lockstitch sewing machine has been exemplified. However, the cloth feed mechanism 30 feeds the workpiece with the feed dog by the combined trajectory of the horizontal movement and the vertical movement, and changes the rotation angle of the feed adjusting body. Thus, the sewing machine can be applied to any type of sewing machine that changes the sewing pitch.

  Further, in a sewing machine that is provided with a feed leg that performs a cloth feed operation by making contact with an article to be sewed from above, called a vertical feed sewing machine or a general feed sewing machine, an upper feed leg mechanism is also connected to the feed adjusting body 55. It is also possible to change the shape of the trajectory of the upper feed leg orbiting operation by controlling the rotation of the feed adjustment body 55 by the control of the feed adjustment motor 57 described in the embodiment of the invention.

11 Needle plate 12 Hook 16 Sewing machine motor 30 Cloth feed mechanism 31 Feed dog 32 Feed base 33 Vertical feed shaft 40 Horizontal feed mechanism 42 Horizontal feed shaft 50 Feed adjustment mechanism 55 Feed adjustment body 57 Feed adjustment motor 60 Vertical feed mechanism 90 Control device 100 Sewing machines a to f, α, β Passing point P1 First sewing pitch P2 Second sewing pitch P3 Third sewing pitch θ1 to θ3 Rotation angle

Claims (7)

A needle up-and-down movement mechanism that moves the needle bar up and down;
A sewing machine motor as a drive source of the needle up-and-down movement mechanism;
A feed dog that feeds the material to be sewn on the needle plate;
A horizontal feed mechanism that obtains power from the sewing machine motor and transmits a reciprocating motion in the horizontal direction to the feed dog;
A vertical feed mechanism for applying a reciprocating motion in the vertical direction to the feed dog;
A feed adjuster that varies the amplitude of a horizontal reciprocating motion transmitted from the sewing machine motor to the feed dog by a turning motion;
A feed adjustment motor that changes and adjusts the sewing pitch by changing the rotation angle of the feed adjustment body;
In a sewing machine comprising a control device for controlling the feed adjustment motor,
The control device controls the feed adjustment motor during one cycle of the vertical movement of the needle bar to change the rotation angle of the feed adjustment body a plurality of times, thereby allowing the trajectory of the feed dog to rotate. A sewing machine characterized by performing control to change the shape.   The control device includes a first sewing pitch that is different in size between a passing point that is the highest position in the trajectory of the feed dog and at least one of two passing points that are the height of the needle plate upper surface. 2. The sewing machine according to claim 1, wherein the feed adjusting motor is controlled so as to be at a rotation angle of the feed adjusting body having a second sewing pitch.   The control device has a rotation angle of the feed adjusting body that becomes the first sewing pitch between a passing point that is the highest position and a passing point that is the lowest position in the trajectory of the feed dog's orbiting operation, 3. The sewing machine according to claim 2, wherein the feed adjusting motor is controlled so as to be a rotation angle of the feed adjusting body that becomes the second sewing pitch at the two passing points.   The control device has a rotation angle of the feed adjusting body that becomes the first sewing pitch between a passing point that is the highest position and a passing point that is the lowest position in the trajectory of the feed dog's orbiting operation, 3. The sewing machine according to claim 2, wherein the feed adjusting motor is controlled so as to have a rotation angle of the feed adjusting body that becomes the second sewing pitch at one of the two passing points.   The sewing machine according to any one of claims 1 to 4, wherein the first sewing pitch is set to a value larger than the second sewing pitch.   The control device includes: a passing point that is the highest position in the trajectory of the feed dog's orbiting operation; one of two passing points that are the needle plate upper surface height; and the other of the two passing points that are the needle plate upper surface height; 2. The sewing machine according to claim 1, wherein the feed adjustment motor is controlled so that the rotation angle of the feed adjustment body becomes the first to third sewing pitches having different sizes.   The sewing machine according to claim 6, wherein the first sewing pitch is set to a value larger than the second sewing pitch, and the third sewing pitch is set to a value larger than the first sewing pitch. .

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