JP2008167897A - Cloth presser device for sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To apply a uniform pressing force to a workpiece in a cloth presser device for sewing machines which moves a retained cloth back and forth and around by XY driving means. <P>SOLUTION: This cloth presser device 1 for sewing machines includes: a cloth feeding arm freely moving in the XY directions on a sewing table by the XY driving means; a cloth pressing arm 20 having one end liftably attached to the cloth feeding arm; a cloth presser 30 rotationally connected to the other end of the cloth pressing arm 20 and pressing the cloth from the upper part; a cylinder device 50 for lifting/lowering the cloth presser 30 to a waiting position and a cloth retaining position; a lower plate 40 retaining the workpiece by cooperation with the cloth presser 30; a torsion coil spring 60 energizing the cloth presser 30 in the direction of lowering the end side; a first stopper 70, when the cloth presser 30 is located in the waiting position, retaining the end in the upper position of the rear end; and a second stopper 80, when the cloth presser 30 is lowered to the cloth retaining position, disposing the lower face of the cloth presser 30 to face the upper face of the cloth. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sewing machine cloth pressing apparatus, and more particularly to a sewing machine cloth pressing apparatus that moves a held cloth in the front-rear and left-right directions by XY driving means.

  2. Description of the Related Art Conventionally, in a cloth presser device for a sewing machine that performs sewing of patterns such as embroidery by moving a holding frame that holds a cloth to be sewn in the X and Y directions, the cloth feed base that can freely move in the X and Y directions on the sewing machine bed A cloth presser support body, one end of which is supported by the cloth feed base so as to be movable up and down, a cloth presser as a holding frame that holds one end fixed to the other end of the cloth presser support body, and presses the cloth from above; A lower plate fixed to the table and moving integrally with the cloth feed table is provided. And, by driving the air cylinder, the cloth presser keeps waiting at the upper standby position when not sewing, and when sewing, the cloth presser descends to the cloth holding position and presses the cloth, and sewing is performed according to preset pattern data. A desired stitch pattern is formed by intermittently moving the cloth in synchronization with the vertical movement of the needle.

Further, in recent years, the cloth presser as shown in FIG. 7 is used instead of the cloth presser support body in view of the decrease in the cloth holding force due to the deformation of the cloth presser due to the increase in the size of the cloth presser and the variation in the thickness of the cloth. Even if there is a variation in the thickness of the cloth (the sewing product M), the arm 120 is used and the vicinity of the center of the cloth presser 130 is pivotally connected to the tip of the arm 120 along the upper surface thereof. A cloth presser device 101 for a sewing machine that is configured to press uniformly is known (for example, see Patent Document 1).
Japanese Patent Laid-Open No. 62-284892

  In the cloth presser device 101 of the sewing machine disclosed in the above-mentioned Patent Document 1, when the thickness of the cloth is not uniform in the front-rear direction along the longitudinal direction of the sewing machine arm, the cloth presser 130 is inclined and its lower surface is made of cloth. A uniform pressing pressure can be applied to the cloth because it is in uniform contact with the upper surface. However, if the thickness of the cloth is not uniform in the left-right direction perpendicular to the longitudinal direction of the sewing machine arm, even if the cloth presser 130 is lowered, it is not evenly contacted with the upper surface of the cloth and is uniformly pressed from above. Therefore, there is a problem that the cloth is displaced during sewing and the sewing quality is deteriorated. In view of such a problem, it is conceivable that the pressure by the air cylinder is increased and the cloth is strongly pressed and held downward. However, in such a case, the frictional force between the sewing machine bed and the lower plate is increased. There has been a problem that the efficiency and durability of the sewing machine operation are reduced, such as the speed of the feeding operation being reduced or the wear of the lower plate and the machine bed becoming severe.

  An object of the present invention is to provide a cloth pressing device for a sewing machine that applies a uniform pressing pressure to a workpiece.

  In order to solve the above-mentioned problems, the invention according to claim 1 is characterized in that a base end portion is erected on a sewing machine bed and moves on the sewing machine bed in an XY direction by an XY driving means, and one end of the cloth is provided on the cloth bed. A cloth presser arm attached to the feed base so as to be movable up and down, a cloth presser that is connected to the other end of the cloth presser arm and presses the workpiece from above, and lifts the cloth presser to an upper standby position and a cloth holding position. Elevating drive means; and biaxial tilting means for tiltably supporting the cloth presser at a tilt angle about two axes parallel to and perpendicular to the upper surface of the sewing machine bed, the biaxial tilting means Has a holding frame connected to the other end of the pressing arm via a first axis and connected to the cloth presser via a second axis orthogonal to the first axis, the first axis being the holding Arranged through the center of gravity of the frame, the second axis is A presser foot device of a sewing machine, characterized in that the arrangement passing through the center of gravity of the serial presser foot.

  The invention according to claim 2 is characterized in that in the invention according to claim 1, there is provided a regulating means for regulating an inclination angle of the holding frame with respect to the cloth presser.

  According to a third aspect of the present invention, in the second aspect of the present invention, the restricting means is an elastic body provided between the holding frame and a cloth presser.

According to the first aspect of the present invention, the cloth presser is tilted about the first axis by the biaxial tilting means, and is also tilted about the second axis in the direction perpendicular to the first axis. Thereby, for example, even if the thickness of the sewing product placed on the sewing machine bed is not uniform in both the X direction and the Y direction, according to the variation in the thickness of the sewing product. The cloth presser is inclined in an arbitrary direction. Therefore, the cloth presser can come into contact with the upper surface of the sewing object or from above according to the variation in the hardness of the sewing object. Thereby, in addition to being able to apply a uniform pressing pressure to the sewing product, it is possible to improve the retainability of the sewing product by the cloth presser and prevent the sewing product from being displaced due to the cloth feeding operation. The deterioration of the sewing quality can be prevented.
Here, the XY direction refers to the longitudinal direction of the sewing machine and the direction orthogonal thereto, and refers to the direction along the horizontal plane orthogonal to the vertical direction of the sewing needle.

  In addition, according to the first aspect of the present invention, it is possible to improve the retainability of the sewing object without increasing the pressing pressure from above by the elevating drive means, so that the frictional force with the sewing machine bed is increased. The retention of the sewing product can be improved without doing so. Accordingly, it is possible to improve the efficiency of the sewing machine operation while reducing the load on the feeding operation due to the increase in friction and preventing the durability of the sewing machine from being lowered. The cloth presser is supported by the pressing arm via a holding frame that can be tilted about the first axis, and is supported by the holding frame so as to be tiltable about the second axis. That is, since the conventional cloth presser can be processed and used as the holding frame, the above-described effects can be obtained with a simple configuration. The holding frame is connected to the other end of the cloth pressing arm around a first axis passing through the center of gravity, and the cloth pressing is connected to the holding frame by a second axis passing through the center of gravity. Thereby, the pressing pressure can be made uniform from one end of the cloth presser to the other end.

  According to the second aspect of the invention, the same effect as that of the first aspect of the invention can be obtained, and in particular, the inclination angle of the holding frame with respect to the cloth presser is regulated by the regulating means. Thereby, when arrange | positioning the said cloth presser in a cloth holding position by a raising / lowering drive means, it can be lowered | hung in parallel with a sewing machine bed. Therefore, when the cloth presser descends, the one end of the cloth presser is first brought into contact with the sewing product, so that it is possible to prevent the position of the sewing product from being displaced, thereby preventing deterioration of the sewing quality. Can do.

  According to the invention described in claim 3, the same effect as that of the invention described in claim 2 can be obtained with a simple configuration by the restricting means made of an elastic body.

  Hereinafter, the best mode of a cloth presser device for a sewing machine according to the present invention will be described in detail with reference to FIGS. However, although various technically preferable limitations for implementing the present invention are given to the embodiments described below, the scope of the invention is not limited to the following embodiments and illustrated examples. In the present embodiment, the direction of each part is determined based on the XYZ axes shown in the drawings. In a state where the sewing machine is installed on a horizontal plane, the Z-axis direction indicates the vertical direction that is the vertical direction, the Y-axis direction indicates the left-right direction that coincides with the longitudinal direction of the sewing machine arm portion (not shown), the X-axis direction is horizontal and the Y-axis The front-rear direction orthogonal to the direction is shown.

<Configuration of cloth presser>
The cloth presser device 1 for a sewing machine according to the present embodiment is mounted on an electronic cycle sewing machine that performs embroidery stitching and the like by moving a cloth as a sewing object in the X and Y directions based on predetermined sewing data.
The sewing machine cloth presser 1 (hereinafter simply referred to as the cloth presser 1) is disposed on a bed portion (sewing bed) of a sewing machine frame (not shown). The sewing machine frame includes a bed portion that forms a lower portion of the sewing machine frame, a vertical trunk portion that is erected upward from one end of the bed portion, and an upper portion of the sewing machine frame that extends from the upper portion of the vertical trunk portion in the longitudinal direction ( And an arm portion (sewing arm) extending along the Y-axis direction), and its outer shape is formed in a substantially U-shape when viewed from the front. In the sewing machine frame, there are provided power transmission mechanisms such as an upper shaft and a lower shaft (not shown) that are rotatable and extend in the front-rear direction. Further, in the present embodiment, the sewing operation is performed by the operator of the sewing machine at the tip of the arm part, that is, the machine surface part side.

As shown in FIGS. 1 and 2, the cloth presser 1 has a cloth feed base 10 whose base end portion stands on the bed portion and moves freely on the bed portion in the XY direction by an XY driving means, and one end thereof. A cloth presser arm 20 that is attached to the cloth feed base 10 so as to be movable up and down, a cloth presser 30 that is connected to the other end of the cloth presser arm 20 and presses the workpiece from above, and one end fixed to the cloth feed base 10 and the other end. Has a lower plate 40 extended so as to face the tip of the cloth presser 30 from below, a cylinder device 50 as a lift drive means for raising and lowering the cloth presser 30 to an upper standby position and a cloth holding position, A holding frame 60 is provided as a biaxial tilting means for tiltably supporting the cloth presser 30 at a tilt angle about two axes that are parallel to the upper surface and perpendicular to each other.
Hereinafter, each part will be described in detail.

The cloth feed base 10 has a base end portion standing on the bed portion and a distal end portion disposed between the arm portion and the bed portion, and the distal end portion moves up and down at the distal end of the arm portion. The shape is extended to the vicinity of the sewing needle and intermediate presser not shown.
The cloth feed base 10 is driven by an X-axis pulse motor and a Y-axis pulse motor (not shown) as XY driving means provided in the bed portion, and can move freely in the XY directions on the bed portion. The X-axis pulse motor and the Y-axis pulse motor respectively apply a driving force in the XY direction to the cloth feed base 10 through a gear mechanism, a driving shaft, a timing belt, a guide rail, and the like (not shown). Note that the drive amount and drive timing of each pulse motor are driven and controlled by a control unit (not shown) independently of a sewing machine motor that is a drive source for needle up-and-down movement in this embodiment.

  As shown in FIG. 1 and FIG. 2, the base end portion of the cloth presser arm 20 is connected to the distal end of the cloth feed base 10 so as to be movable up and down and detachably along the Z-axis direction. The front end of the cloth presser arm 20 is divided into two forks and extends in parallel to the sewing machine surface portion side, and is an arm member having a substantially U shape in plan view. The cloth presser arm 20 is driven up and down in accordance with the driving of a cylinder device 50 to be described later while the two tip portions are maintained in a horizontal state. The cloth presser arm 20, a cloth presser 30 and a holding frame 60, which will be described later, can be replaced with various sizes depending on the size of the cloth to be sewn.

  For example, as shown in FIG. 1, the holding frame 60 is a rectangular frame having an opening penetrating in the vertical direction, and the insides of the four sides are greatly opened. The holding frame 60 is rotatably connected to the distal end portion of the cloth pressing arm 20 in the middle between one end and the other end of two sides parallel to the Y-axis direction. Specifically, the holding frame 60 rotates around the connecting shaft 61 along the X-axis direction with respect to the distal end portion of the cloth pressing arm 20 at the center in the longitudinal direction of two sides parallel to the Y-axis direction. It is connected freely. The connecting shaft 61 is disposed in parallel with the upper surface of the bed portion and is disposed so as to pass through the center of gravity of the holding frame 60, and functions as the first shaft of the biaxial tilting means in the present embodiment. As a result, the holding frame 60 is always supported by the cloth pressing arm 20 in a state parallel to the upper surface of the bed portion, and the inclination angle of two sides parallel to the Y-axis direction is the direction of arrow A shown in FIG. Alternatively, it can be inclined in the direction of arrow B.

In addition, coil springs 70 and 70 are provided on the lower surface of the holding frame 60 as regulating means for regulating the inclination angle of the holding frame 60 with respect to the cloth presser 30 at the center of each of the two sides along the Y-axis direction. Further, support portions 62 and 62 for supporting the cloth presser 30 are provided at the central portions of the two sides along the X-axis direction.
As shown in FIGS. 5A and 5B, the coil spring 70 is externally inserted in an intermediate portion of a pin 71 loosely inserted in a hole portion 63 that vertically penetrates the holding frame 60. The coil spring 70 has a lower end abutted against a flange portion 71 a provided at the lower end of the pin 71 and an upper end abutted against the lower surface of the holding frame 60, and always biases the pin 71 downward. It is like that. On the other hand, the upper end portion of the pin 71 protruding above the holding frame 60 is a male screw, and a nut 72 is fixed to the male screw, thereby restricting the downward movement of the pin 71 due to the urging force of the coil spring 70. It is like that. Thus, the coil spring 70 functions as an elastic body in the present embodiment provided between the holding frame 60 and the cloth presser 30.

  The coil springs 70, 70 are set to have the same projection distance D (see FIG. 5A) from the lower surface of the holding frame 60, and the cloth presser 30 described later is supported in parallel with the holding frame 60. In this state, the lower ends of the pins 71 and 71 are both set to a distance where they are in contact with the upper surface of the cloth presser 30. That is, the inclination angle of the holding frame 60 with respect to the cloth presser 30 is always regulated horizontally by the coil springs 70 and 70 and the pins 71 and 71. In addition, the elastic constant of the coil spring 70 is set so as to be sufficiently weaker than the downward pressing force applied to the cloth presser 30 by the cylinder device 50 that is the lifting drive means. When the cloth presser 30 is disposed at the cloth holding position, the coil spring 70 contracts (see FIG. 5B), so that the inclination of the cloth presser 30 (see FIG. 6C) is not hindered. ing.

  For example, as shown in FIG. 1, the cloth presser 30 is a rectangular frame having an opening penetrating in the vertical direction, like the holding frame 60, and the insides of the four sides are greatly opened. The cloth presser 30 has substantially the same size as the holding frame 60, and can freely rotate on the lower surface of the holding frame 60 facing each other in the middle between one end and the other end of the two sides parallel to the X-axis direction. It is connected. Specifically, the cloth presser 30 is connected to the lower surface portion of the holding frame 60 around the connecting shaft 31 along the Y-axis direction at the center in the longitudinal direction of two sides parallel to the X-axis direction. Yes. The connecting shaft 31 is disposed so as to be orthogonal to the connecting shaft 61 serving as the first shaft and to pass through the center of gravity of the cloth presser 30, and functions as the second shaft of the biaxial tilting means in the present embodiment. Thereby, the cloth presser 30 has variable inclination angles of two sides parallel to the X-axis direction (see FIG. 4).

  The cloth presser 30 moves up and down integrally with the cloth presser arm 20 when the cloth presser arm 20 moves up and down in response to driving of a cylinder device 50 described later. And when descending, the cloth M placed on the lower plate 40 (described later) is disposed at a cloth holding position that presses the cloth M from above, and is held on the upper surface of the bed portion while holding the cloth M held in cooperation with the lower plate 40. Along the XY direction. That is, the cloth presser 30 holds the cloth M and moves the held cloth M in the front-rear and left-right directions (XY directions) together with the cloth presser 30 as the X-axis pulse motor and the Y-axis pulse motor are driven. Then, the movement of the cloth presser 30 and the operation of a sewing needle and a hook (not shown) are interlocked so that the needle M is dropped on the cloth M held inside the opening, and based on predetermined sewing data. A seam pattern is formed. Here, the predetermined sewing data refers to, for example, data relating to XY coordinate data, feed pitch, etc. of all needle drop points set for each stitch in advance in order to form various patterns. Are stored in a storage device or an external storage device of a control unit (not shown) in this embodiment.

  As shown in FIGS. 1 to 3, the base plate (rear end) portion of the lower plate 40 is connected to the front lower end of the base end portion of the cloth feed base 10 described above, and the tip portion is the upper surface of the bed portion. Is extended to the front side of the bed portion. The tip of the lower plate 40 is formed in a square frame shape that is substantially the same shape as the tip of the cloth presser 30, and is disposed so as to face the cloth presser 30 from below. Then, the cloth placed on the tip is held together with the cloth presser 30 described above to hold the cloth, and the needle drop by the sewing needle is performed inside the frame of the tip.

  The cylinder device 50 is arranged on both sides of the cloth feed base 10 and is composed of a pair of air cylinders that use air as a fluid. Such an air cylinder includes a cylinder attached to the cloth feed base 10, a piston rod that advances and retreats in response to depression of a depression pedal (not shown), and an electromagnetic valve for adjusting the amount of air supplied into the cylinder. The conventionally well-known structure is taken. The cylinder device 50 moves the cloth presser 30 up and down to a cloth holding position where the cloth presser 30 is lowered and presses the cloth M from above and to an upper standby position where the cloth presser 30 is retracted upward and disposed at the upper position.

(Explanation of cloth presser operation)
Next, operation | movement description of the cloth presser 1 provided with the said structure is performed. In the present embodiment, an example will be described in which the thickness of the fabric M is non-uniform in the X-axis direction and the right side shown in FIGS.
As shown in FIG. 6A, when the cloth presser 30 is disposed at the upper standby position, the pins 71 and 71 protrude downward by the biasing force of the coil springs 70 and 70, and the pins 71 and 71 All the tips (lower ends) are in contact with the upper surface of the cloth presser 30. Thereby, the inclination angle of the cloth presser 30 with respect to the holding frame 60 is maintained in a horizontal state. In the present embodiment, since the connecting shaft 61 is disposed so as to pass through the center of gravity of the holding frame 60, in this state, the cloth presser 30 is disposed horizontally, that is, parallel to the upper surface of the bed portion.
Next, when the cloth presser arm 20 and the cloth presser 30 are lowered by driving the cylinder device 50, one end side (the right side in FIG. 6B) of the cloth presser 30 in the X-axis direction is the upper surface of the cloth M during the lowering. It will contact | abut.
When the cloth presser 30 is further lowered, the cloth presser 30 is rotated in the direction of arrow C around the connecting shaft 31, and the cloth presser 30 is inclined according to the thickness of the fabric M. At this time, as shown in FIG. 5B and FIG. 6C, one coil spring 70 contracts and the thickness of the fabric M is absorbed. On the other hand, the length of the other coil spring 70 does not change, and the upper surface of the cloth presser 30 is separated from the lower end of the pin 71. When the cloth is lowered to the lowermost cloth holding position, the entire lower surface of the cloth presser 30 is brought into contact with the upper surface of the cloth M as shown in FIG. As a result, the entire fabric M placed on the upper surface of the lower plate 40 is uniformly pressed downward by the fabric presser 30, and the fabric M is held by the fabric presser 30 and the lower plate 40. In this state, the cloth M is moved in the XY directions by driving the X-axis pulse motor and the Y-axis pulse motor.
Further, even when the thickness of the fabric M is not uniform in the Y-axis direction, the holding frame 60 and the fabric presser 60 are inclined in the direction of arrow A or B as shown in FIG. Variations in thickness are absorbed. That is, according to the cloth presser 1 according to the present embodiment, the cloth presser 30 is inclined at an arbitrary inclination angle centering on two axes that are parallel to the upper surface of the bed portion and orthogonal to each other.
In the present embodiment, the case where the thickness of the fabric M is thick only on the right side in FIGS. 6A to 6C is illustrated, but it goes without saying that the same applies to the case where the left side is thick.

(Effect of embodiment)
As described above, according to the cloth presser device 1 for a sewing machine according to the present embodiment, even when the thickness and hardness of the fabric M are not uniform in the X-axis direction as well as the Y-axis direction, The cloth presser 30 can be brought into contact with each other. Thereby, in addition to being able to apply a uniform pressing pressure to the fabric M, it is possible to prevent the displacement of the fabric M accompanying the fabric feeding operation because the retainability of the fabric M by the fabric presser 30 is improved. Accordingly, it is possible to prevent a reduction in sewing quality.
Further, since the retainability of the fabric M can be improved without increasing the frictional force between the bed portion and the lower plate 40, the load on the feeding operation due to the increase in the friction is reduced, and the durability of the sewing machine is reduced. Therefore, it is possible to improve the efficiency of the sewing machine operation while preventing the performance from being lowered. Further, the pressing pressure can be made uniform from one end of the cloth presser 30 to the other end by the connecting shaft 61 passing through the center of gravity of the holding frame 60 and the connecting shaft 31 passing through the center of gravity of the cloth presser 30.
Further, when the cloth presser 30 is disposed at the cloth holding position by the cylinder device 50, the cloth M can be lowered in parallel with the bed portion, so that one end of the cloth presser 30 comes into contact with the cloth M first. Can be prevented. Accordingly, it is possible to prevent a reduction in sewing quality.

  The restricting means may be formed of rubber or resin. That is, when rubber or resin is used as the pin 71, it is possible to reduce the sound generated when the upper surface of the cloth presser 30 is in contact with the pin 71. Alternatively, a sufficiently soft rubber or resin that allows the inclination of the cloth presser 30 may be attached to the lower surface of the holding frame 60 without using the coil spring 70. Further, this restricting means may be provided on the upper surface side of the cloth presser 30.

It is a disassembled perspective view which shows the principal part structure of the cloth pressing device of the sewing machine which is this embodiment. It is a perspective view which shows the cloth pressing device of the sewing machine which is this embodiment. It is a side view which shows the cloth pressing device of the sewing machine which is this embodiment. It is a front view which shows the cloth presser in this embodiment. It is the schematic which shows the control means in this embodiment. It is operation | movement explanatory drawing which shows operation | movement of the cloth pressing device of the sewing machine which is this embodiment. (A) is an upper standby position, (b) is a lowering (upward), and (c) is a cloth holding position. It is a side view which shows the cloth presser device of the conventional sewing machine.

Explanation of symbols

1 Fabric holding device (cloth holding device for sewing machine)
10 Cloth feed base 20 Cloth presser arm 30 Cloth presser 31 Connection shaft (second shaft)
40 Lower plate 50 Cylinder device (lifting drive means)
60 Holding frame (biaxial tilting means)
61 Connecting shaft (first shaft)
62 Supporting part 70 Coil spring (regulating means, elastic body)
71 Pin M Cloth (Sewing product)

Claims (3)

A cloth feed base having a base end portion standing on the sewing machine bed and moving freely on the sewing machine bed in the XY directions by an XY driving means;
A cloth presser arm having one end attached to the cloth feed base so as to be movable up and down;
A cloth presser that is connected to the other end of the cloth presser arm and presses the workpiece from above;
Elevating drive means for elevating the cloth presser to an upper standby position and a cloth holding position;
A biaxial tilting means for tiltably supporting the cloth presser at an inclination angle centered on two axes that are parallel to the upper surface of the sewing machine bed and perpendicular to each other;
The biaxial tilting means has a holding frame connected to the other end of the pressing arm via a first axis and connected to the cloth presser via a second axis orthogonal to the first axis,
The sewing machine cloth presser apparatus according to claim 1, wherein the first axis is arranged to pass through the center of gravity of the holding frame, and the second axis is set to pass through the center of gravity of the cloth presser.   The cloth presser device for a sewing machine according to claim 1, further comprising restricting means for restricting an inclination angle of the holding frame with respect to the cloth presser.   The sewing machine cloth presser apparatus according to claim 2, wherein the restricting means is an elastic body provided between the holding frame and the cloth presser.

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