JP7012327B2 - sewing machine - Google Patents

Description

The present invention relates to a sewing machine, particularly a sewing machine for embroidery.

There are many types of sewing machines, one of which is an embroidery sewing machine. Embroidery machines are used to sew appliqués on cloth and to cover surface areas with thread. The difference from a normal sewing machine is that it sews a bulging part that bulges more than other parts formed on the surface of the cloth. This bulge provides a three-dimensional effect peculiar to an embroidery product, and it is desirable to prevent the bulge from being crushed in order to maintain the quality of embroidery.
However, even with an embroidery sewing machine, it is necessary to press the cloth surface with a cloth presser in order to smoothly insert and remove needles during work. Therefore, there is a problem that the bulging portion is crushed by this cloth retainer and the quality of embroidery is deteriorated.

Cited Document 1 proposes to stop the sewing machine operation and change the height position of the cloth retainer upward when the needle drop position overlaps the bulging portion in order to solve the above problem. However, this method has a problem that the work efficiency is lowered because the sewing machine operation is stopped.
Cited Document 2 proposes a method in which the height of the cloth presser is stored in advance for the area to be embroidered, and the embroidery is performed while changing the height of the cloth presser based on the data. However, this method requires a step of memorizing the height of the cloth presser, and there is still a problem that the overall work efficiency is lowered.

Japanese Unexamined Patent Publication No. 2007-289349 Japanese Unexamined Patent Publication No. 2008-006088

In view of the above problems, it is an object of the present invention to provide a sewing machine capable of changing the height position of the cloth presser so as not to crush the bulging portion without lowering the work efficiency.

According to the invention of claim 1,
It ’s a sewing machine,
A needle bar equipped with a needle, which is moved up and down by a needle drive motor to insert and remove the needle into the processed cloth.
A cloth pressing means that holds the processed cloth when inserting and removing a needle from the processed cloth, and a cloth pressing means that is moved up and down by a cloth pressing driving motor.
A cloth moving device that moves the processed cloth while the needle is being pulled out,
A cloth height detecting means that detects the cloth height from the height position of the cloth holding means when the cloth is pressed, and a cloth height detecting means.
Equipped with
The cloth moving device moves the processed cloth so that the needle can be inserted and removed at the new position after the needle has been inserted and removed at one position.
The cloth presser is lowered at a new position, and the cloth height is detected from the height position of the cloth presser means when the cloth presser presses the cloth by the cloth height detecting means.
With the processed cloth pressed by the cloth pressing means at the height detected by the cloth height detecting means, the needle is inserted and removed from the processed cloth to perform embroidery.
A sewing machine characterized by this is provided.

In the invention of claim 2, the cloth height detecting means includes a displacement display member that displays a displacement in response to a change in the height position of the cloth holding means, and a sensor member that detects the displacement displayed by the displacement display member. ..
In the invention of claim 3, the displacement display member is a slit attached to the member that is displaced in response to a change in the height position of the cloth holding means.
The sensor member is a photoelectric sensor including a light emitting member and a light receiving member of light passing through an optical path opened and closed by the slit.
In the invention of claim 4, the slit of the cloth height detecting means is formed in the rotary disk attached to the shaft of the cloth presser drive motor.
In the invention of claim 5, the slit of the cloth height detecting means is fixed to the cloth holding means which is moved up and down.

In the invention of claim 6, the rotational driving force of the cloth pressing driving motor is converted into a linear driving force by the link mechanism, and the linear driving force is transmitted to the cloth pressing means to move the cloth pressing means up and down. ..
In the invention of claim 7, the linear driving force is transmitted to the cloth pressing means via a spring.

The invention according to claim 8 has a standby detecting means for detecting that the cloth retainer has come to the upper standby position, and after the standby detecting means detects that the cloth retainer has come to the upper standby position, the cloth is clothed. The moving device moves the processed cloth to the next needle insertion / removal position.

The sewing machine according to the present invention is a needle bar provided with a needle, which is moved up and down by a needle driving motor to insert and remove the needle from the processed cloth, and a processed cloth when inserting and removing the needle from the processed cloth. The cloth holding means that holds the cloth, which is moved up and down by the cloth holding drive motor, the cloth moving device that moves the processed cloth while the needle is being pulled out, and the cloth when the cloth is held. It is equipped with a cloth height detecting means that detects the cloth height from the height position of the pressing means.
After the insertion and removal of the needle at one position is completed, the cloth moving device moves the processed cloth so that the needle can be inserted and removed at the new position, lowers the cloth retainer at the new position, and uses the cloth height detecting means. The cloth height is detected from the height position of the cloth pressing means when the cloth presser presses the cloth, and the processed cloth is pressed by the cloth pressing means at the height detected by the cloth height detecting means, and the processed cloth is applied. On the other hand, the needle is inserted and removed to perform embroidery. Therefore, the cloth presser presses the cloth according to the cloth height, so that the bulging portion is prevented from being crushed.

It is a perspective view of the 1st Embodiment of this invention. It is a perspective view seen from another direction of the 1st Embodiment of this invention. It is a side view seen from the A direction of FIG. It is a side view seen from the B direction of FIG. It is a figure which shows the square cloth fixing frame. It is a figure which shows the round fixed frame. (A) It is a figure which shows the position of the cloth presser when the cloth is thin. (B) It is a figure which shows the position of the cloth presser when the cloth is thick. It is a figure which shows the movement with time change of a cloth presser and a needle. It is a flowchart which shows the operation by the sewing machine by this invention. It is a figure which looked at the 2nd Embodiment of this invention from the same direction as FIG. It is a figure which shows the laser type height detection apparatus in the 3rd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
Reference numeral 1 indicates an embroidery machine frame attached to a frame (not shown). The embroidery machine frame 1 has a side wall 1a and a bottom wall 1b. The motor mounting member 2 is mounted on the side wall 1a (the notched portion in FIG. 1) of the embroidery machine frame 1. The motor 3 is attached to the motor attachment member 2. The first link member 5 is fixed to the shaft 4 of the motor 3, and the second link member 6 is rotatably connected to the first link member 5.
On the other hand, two guide rods are erected on the bottom portion 1b of the embroidery machine frame 1. A slider 8 is slidably attached to the guide rod 7. The slider 8 is supported by the slider support member 9, and the slider support member 9 is rotatably attached to the second link member 6.

The cloth retainer 11 is attached to the slider support member 9 via the cloth retainer attachment member 10. The cloth retainer 11 has an upper arm 12 whose upper end is coupled to the cloth retainer mounting member 11 and extends in the vertical direction, a lower arm 14 coupled to the lower end of the upper arm 12 via an intermediate portion 13 which extends short in the lateral direction, and a lower arm. It has a pressing portion 15 attached to the lower end of 14 and the lower surface presses the cloth.
A height indicator bar 30 is attached to the slider support member 9 to detect whether the cloth retainer 11 is in the upper standby position, and a standby position sensor 31 for detecting the passage of the height indicator bar 30 is a motor. It is attached to the mounting member 2.

Concentric holes 10d, 13d, and 15d are formed in the cloth holding member 10, the intermediate portion 13, and the pressing portion 15, the holes 10d and 13d have the same diameter, and the needle bar 16 moves up and down in the holes 10d and 13d. Move. A needle 18 is attached to the lower end of the needle bar 16 via a needle attachment member 17. The hole 15d has a diameter smaller than that of the holes 10d and 13d, and the needle 18 moves up and down in the hole 15d.

A disk with slits (not shown) in which a large number of thin slits are formed radially is attached to the opposite side of the shaft 4 of the motor 3. A photoelectric sensor 21 that detects the amount of rotational displacement of the disk with a slit by the light transmitted through the slit is attached to the motor 3 via the sensor support member 22. As will be described later, the disk with slits and the sensor 21 detect that the cloth presser 11 has come into contact with the surface of the processed cloth 100, stop the cloth presser 11, and prevent the cloth presser 11 from further lowering.

FIG. 5 shows a rectangular cloth fixing frame 40 for fixing the processed cloth 100 to be embroidered. The cloth fixing frame 40 is also arranged on a frame (not shown) like the embroidery machine frame, and can be moved in the X-axis direction and the Y-axis direction by the X-axis moving motor 41 and the Y-axis moving motor 42. The cloth fixing frame 40 has an outer frame 40a and an inner frame 40b, and the processed cloth is sandwiched between the outer frame 40a and the inner frame 40b and stretched and held so as to be embroidered by an appropriate method not described in detail.

FIG. 6 shows a circular cloth fixing frame 50 for the processed cloth 100 to be embroidered, and can be moved in the rotational direction and the radial direction by the rotary movement motor 51 and the radial movement motor 52. Similarly, the cloth fixing frame 50 has an outer frame 50a and an inner frame 50b, and the processed cloth is sandwiched between the outer frame 50a and the inner frame 50b and stretched and held so as to be embroidered by an appropriate method not described in detail. ..

Hereinafter, the operation of embroidering the processed cloth 100 using the sewing machine configured as described above will be described.
FIG. 7A shows a state in which the cloth retainer 11 presses the surface 100a of the region of the processed cloth 100 where there is no bulge. The lower surface 15a of the pressing portion 15 of the cloth retainer 11 is located above the surface 100a of the region of the processed cloth 100 where there is no bulging portion by a distance A in the initial state. The needle 18 is also in the upper standby position. When the cloth retainer 11 descends from this state, it reaches the upper surface 100a of the processed cloth 100, and the cloth retainer 11 stops there. That is, the cloth retainer 11 descends by the distance A. The sensor 21 detects and stores how far the slitted disk attached to the motor 3 has rotated when the upper surface 100a of the processed cloth 100 is reached. This is done by capturing the discrepancy between the command and the result that the signal of the sensor 21 indicates a stop even though the command to lower the motor 3 is issued, and by capturing the rotation angle of the motor at that time. ..

On the other hand, FIG. 7B shows a state in which the pressing portion 15 of the cloth pressing 11 presses the surface 101a of the bulging portion 101 formed on the surface of the surface of the processed cloth 100. Assuming that the height of the bulging portion is B, it descends by the distance AB and is stopped at the place. This catches the appearance of a discrepancy between the command and the result that the signal of the sensor 21 indicates a stop even though the command to lower the motor 3 is issued, and the further rotation of the motor 3 is stopped accordingly. It is done by doing.

FIG. 8 is a diagram showing movements of the pressing portion 15 and the needle bar 16 of the cloth retainer 11 with the passage of time. The dotted line indicates the position of the tip of the needle 18. The solid line shows the position of the lower surface of the pressing portion 15 when the cloth retainer 11 is moved in the first pattern.
At t ₀ , it is shown that the pressing portion 15 and the needle bar 16 are in the upper standby position.
At t ₁ , both the pressing portion 15 and the needle bar 16 are slightly lowered.
At t2, _both the pressing portion 15 and the needle bar 16 are shown in a state of being slightly lowered.
At t3 _, the pressing portion 15 reaches the surface of the cloth 100 and is stopped, but the needle bar 16 further descends.
At _t4 , the pressing portion 15 is stopped at the surface of the cloth 100, but the needle bar 16 has reached the lowest point.
_At t5, the pressing portion 15 is stopped at the surface of the cloth 100, but the needle bar 16 is slightly raised from the lowest point.
At t6, the pressing portion ₁₅ also separates from the surface of the cloth 100 and moves upward, and the needle bar 16 is further raised.
At t ₇ , the pressing portion 15 also separates from the surface of the cloth 100 and moves upward, and the needle bar 16 is further raised.
_At t8, the state of returning to the original standby position is shown.

In FIG. 8, what is indicated by the alternate long and short dash line indicates the position of the lower surface of the pressing portion 15 when the cloth retainer 11 is moved in the second pattern. In the second pattern, the cloth retainer 11 descends earlier than in the first pattern, and the time for pressing the cloth 100 by the cloth retainer 11 is longer, so that the cloth can be pressed more reliably.

FIG. 9 is a flowchart illustrating the operation.
In step S1, the processed cloth is moved according to the position of the next needle descent.
In step S2, the cloth retainer and the needle bar are lowered.
In step S3, it is determined whether or not there is a cloth holding stop request, and if a negative determination is made, the process returns to step S2, and if an affirmative determination is made, the process proceeds to step S4.
In step S4, the cloth presser is stopped (the cloth presser drive motor is stopped).
In step S5, it is determined whether or not the needle bar has reached the lowest point, and if a negative determination is made, the process is repeated, and if an affirmative determination is made, the process proceeds to step S6.
In step S6, the needle bar is stopped.
In step S7, the cloth holder and the needle bar are raised.
In step S8, it is determined whether or not the cloth holder and the needle bar have returned to the initial position. If a negative determination is made, the process returns to step S7, and if an affirmative determination is made, the process proceeds to step S9.
In step S9, the cloth holder and the needle bar are stopped at the initial positions.

Since the present invention is configured and operates as described above, even if there is a bulging portion on the cloth, the bulging portion can be embroidered without being crushed.

FIG. 10 is a diagram illustrating a height detection mechanism of the cloth retainer 11 in the second embodiment.
In this second embodiment, the slider support member 9 is divided into an upper slider support member 9a connected to the second link member 5 and a lower slider support member 9b to which the cloth retainer mounting member 10 is connected, and the upper slider support member 9 is connected. The 9a and the lower slider support member 9b are connected via a coil spring 9c having a weak spring force. A slit plate 9d in which a large number of slits are formed in parallel in the height direction is attached to the lower slider support member 9b.

On the other hand, for example, a photoelectric sensor 40 is attached to the bottom wall 1b of the embroidery machine frame 1, and the photoelectric sensor 40 has two portions arranged so as to sandwich the slit of the slit plate 9d. A light emitting unit is provided on one side and a light receiving unit is provided on the other side.
The lower end portion (not shown) of the cloth presser 11 is provided with the same pressing portion 15 as in the first embodiment. The pressing portion 15 abuts on the surface of the processed cloth 200 with the weak spring force of the coil spring 9c. When the height position of the surface of the processed cloth 100 changes, the height position of the slit plate 9d changes. As a result, where the light of the photoelectric sensor 40 passes through the slit plate 9d, that is, which slit of the slit plate 9d changes. As a result, the height of the pressing portion 15 of the cloth retainer 11 changes according to the changed height of the processed cloth 100.

Although the present invention is intended for a general sewing machine, it is particularly effective when applied to an embroidery sewing machine.

1 Embroidery machine frame 2 Motor mounting member 3 Motor 3a Motor shaft 4 1st link member 5 2nd link member 6 Connecting shaft 7 Guide rod 8 Slider 9 Slider support member 9a Upper slider support member 9b Lower slider support member 9c Coil spring 9d Slit Board 9d
10 Cloth retainer mounting member 11 Cloth retainer 15 Pressing part 16 Needle bar 18 Needle 20 Slit disk 21 Sensor 30 Height indicator bar 31 Standby position sensor 40 Cloth fixing frame 50 Cloth fixing frame

Claims (3)

It ’s a sewing machine,
A needle bar equipped with a needle, which is moved up and down by a needle drive motor to insert and remove the needle into the processed cloth.
It is a cloth holding means that holds the processed cloth when inserting and removing the needle from the processed cloth. The rotational driving force of the cloth holding driving motor is converted into a linear driving force by the link mechanism, and the linear driving force is obtained. The cloth holding means that the force is transmitted to the cloth holding means to move the cloth holding means up and down, and the cloth holding means.
A cloth moving device that moves the processed cloth while the needle is being pulled out,
A cloth height detecting means that detects the cloth height from the height position of the cloth holding means when the cloth is held, and a cloth height detecting means.
Equipped with
The cloth moving device moves the processed cloth so that the needle can be inserted and removed at the new position after the needle has been inserted and removed at one position.
The cloth retainer is lowered at a new position, and the cloth height detection means detects the cloth height from the height position of the cloth retainer when the cloth retainer presses the cloth.
In a sewing machine that embroiders by inserting and removing a needle from the processed cloth while the processed cloth is pressed by the cloth pressing means at the height detected by the cloth height detecting means.
The cloth height detecting means includes a slit formed in a rotating disk attached to the shaft of the cloth holding drive motor, and a photoelectric sensor including a light emitting member and a light receiving member of light passing through an optical path opened and closed by the slit. Equipped with
During the embroidery operation, when the cloth retainer moves toward the processed cloth and reaches the upper surface of the processed cloth and stops there, the signal of the photoelectric sensor stops while the descent command of the cloth retainer drive motor is sent. Based on the discrepancy between the command and the result that it is shown, the cloth height is detected by stopping the further rotation of the cloth holding drive motor and detecting the rotation angle of the motor at that time. And
The cloth holding means has a cloth holding mounting member which is connected to the cloth holding driving motor via a link mechanism and has a hole for passing a needle rod, and a hole which is connected to the cloth holding mounting member and passes through the end of the needle tip. The sewing machine is provided with a cloth retainer, and the cloth retainer mounting member can move up and down along the needle rod relative to the needle rod. The sewing machine according to claim 1, wherein the linear driving force is transmitted to the cloth pressing means via a spring. It has a standby detection means that detects that the cloth retainer has come to the upper standby position, and after the standby detection means detects that the cloth retainer has come to the upper standby position, the cloth moving device next to the processed cloth. Move to the insertion / removal position of the needle,
The sewing machine according to claim 1 or 2, wherein the sewing machine is characterized by the above.

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