JPH0687916B2 - Upper thread feeder - Google Patents

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a needle thread feeder for a sewing machine.

2. Description of the Related Art Conventionally, as shown in FIG. 20, a needle thread supply device of this type includes a yarn feeding means 1, a first yarn gripping means 2 arranged before the yarn feeding means, and a yarn feeding means. The second yarn gripping means 3 arranged at the rear stage. As shown in FIG. 21, the yarn feeding means comprises a driving roller 4 and one driven roller 5 which can come into contact with the driving roller 4. The driven roller is supported by the lever 6 and is pressed against the drive roller by the spring 7. The first and second thread gripping means are composed of a magnet 8 and a gripping plate 12 which is supported by a shaft 9 of the magnet and can grip an upper thread 11 between a body 10 of the magnet. The upper thread 11 is pulled out from the spool 13 and passes through the first thread gripping means 2, then between the driving roller 4 and the driven roller 5, and then through the second thread gripping means 3 toward the unillustrated balance. , Through this balance to a needle not shown.

However, in the prior art as described above, it was difficult to pass the knotted yarn between the first and second yarn gripping means or the driving roller and the driven roller. It is an object of the present invention to provide a practically useful needle thread feeder that overcomes the above-mentioned drawbacks of the prior art.

In order to achieve the above-mentioned object, in the present invention, a first yarn feeding means and a first and a second yarn gripping means are attached so that a knot of the yarn can be passed smoothly. The second frame having the thread guide member attached thereto was made movable.

The second frame is movable with respect to the first frame so as to dispose the yarn guiding member in the yarn path or move away from the thread path.

Embodiments of the present invention will now be described in detail with reference to the drawings.
Explained. 1 to 4, according to the present invention
A needle thread feeder is shown. This device is
Is applied to a two-needle sewing machine. This needle thread feeder is
The first frame 20 fixed to the sewing machine body (not shown)
A second flap movably mounted on this first frame
Lame 21 and. Thread puller on the first frame
The step 22 and a plurality of first stages arranged in front of the yarn feeding means.
Of the yarn gripping means 23, 23 'and the yarn feeding means
The second thread gripping means 24 is attached. Thread reel
The discharging means is a thread winding bobbin (not shown) for each needle thread for two needles.
Draw a predetermined amount from. In more detail, this thread feeder
The step 22 extends along the drive roller 25 and the axial direction of the drive roller.
Are arranged side by side and arranged so that they can contact the drive roller.
Consisting of two driven rollers 26a and 26b
It One driven roller 26a is connected to the drive roller 25.
Grasping the first upper thread 27a (shown by the solid line in FIG. 3)
Pull out the upper thread from the bobbin by a specified amount and use the other driven thread.
Of the second upper thread 27b between the roller 26b and the drive roller 25.
Grasp the upper thread (shown by the broken line in Fig. 3) and wind the bobbin
A predetermined amount from the The drive roller 25 is a model not shown.
The rotation of this motor is controlled by the motor.
Controlled by means. Driven rollers 26a, 26b
Is supported on the lever 28. One end of this lever is a shaft
It is attached to the first frame 20 by 29 so that it can swing.
Has been. The driven rollers 26a and 26b are formed as levers.
It is rotatably attached to the bearing 28a. Leva
A driven roller driving means is provided at the other end of the roller. This
The driven roller driving means of the
For pressing and separating from the drive roller
Of. This driven roller drive means is
The lever is pressed so that the driven roller is pressed against the drive roller.
The spring 30 for urging the spring and the driven roller against the spring 30.
Latch voltage that drives the lever away from the drive roller
And a magnet 60 (schematically shown in FIG. 12).
One end of the spring 30 is attached to the other end (free end) of the lever 28.
The other end of this spring is attached to the spring support member 31.
ing. This spring support member is shown in FIG. 1 and FIG.
It has a slot 31a extending in the direction. This spring support member
Is inserted into the slot and screwed into the second frame.
Movably fixed to the second frame by the screw 32
To be done. Loosen the screw 32 and move the spring support member vertically.
The moving roller changes the spring pressure to drive the driven roller.
It is possible to change the pressure applied to the la. Example above
Then, two driven rollers are supported by one lever 28.
However, as shown in FIG. 8, each of the two driven rollers is
First and second levers 33a, 3 respectively independently arranged
You may make it support each of 3b. In this case,
The driven roller drive as described above is applied to each of the first and second levers.
Means are provided. Therefore, these levers are independent
It is operational. The driven roller driving means described above will be described later.
It is controlled by the control means. Independent of each driven roller
To control, especially to perform sewing using multiple needles
In this case, it is useful to independently feed the upper thread to be fed to each needle.
It is effective. That is, each lever is operated to drive the driven roller 2
6a and 26b are brought into contact with or separated from the driving roller 25.
For example, by feeding one needle thread,
Can be controlled so that the upper thread of the other
It Separately, two driven rollers are connected to one lever 2
In the form supported by 8 (see FIG. 1), a plurality of first
Each of the thread gripping means is controlled by the control means to provide two needle threads.
You can also change the feed. First and second thread gripping hands
Steps 23, 23 'and 24 are electromagnet grippers in the illustrated embodiment.
It consists of structures. This electromagnet gripping mechanism is connected to the electromagnet 34 and this electromagnet.
And a grip plate 35 driven by a magnet. Electromagnet 3
4 is a main body 34a and magnetic field generating means housed in the main body
(Not shown) and the main body are supported so that they can move linearly and generate a magnetic field
Shaft 34b driven by means. Small
The holding plate 35 is supported on the tip of this shaft. Upper thread
Is inserted between the end surface of the main body 34a and the grip plate. electromagnetic
The stone is controlled by the control means described later. With electromagnet
When the gripping plate is urged and moved toward the main body, the upper thread grips
It is gripped between the plate and the end face of the main unit, and the grip plate is separated from the main unit.
Then, the upper thread is released. Incidentally, the above-mentioned yarn feeding means, first and second
The second and second thread gripping means are not limited to the above embodiment. second
The frame 21 of is substantially parallel to the first frame and
They are arranged at intervals (see FIGS. 1 and 2).
This second frame is moved by the movable support means 36 into the first frame.
Mounted on the frame. This movable support means
Is a plurality of guide shafts 37 fixed to the first frame 20.
Have. Hole 3 into which the guide shaft is inserted in the second frame
8 are provided. Bolt 3 is attached to the other end of the guide shaft 37.
9 screwed in, these bolts and the surface of the second frame
A compression spring 40 is arranged between the and. Assembly order
To mount it easily, first fix the guide shaft on the first frame.
Set. Install the guide shaft in the hole 38 in the second frame.
Attach it to the first frame as it is inserted. Next
, Insert the compression spring 40 into the guide shaft, and finally attach the bolt.
Screw on the guide shaft. Thus, the second frame 21 is
As shown in FIG. 1, an arrow Y is shown on the first frame 20.
It can be mounted so that it can move in any direction. Second frame
21 has the first to fifth parts on the surface opposite to the first frame.
Thread guide members 41 to 45 are attached. First and first
One threading hole 46 is provided in each of the second thread guiding members 41, 42.
Are provided, and the third to fifth yarn guide members 43 to 45 are respectively provided.
Two threading holes 46 are provided. First thread guide
The material 41 uses the first upper thread 27a from the bobbin as the thread.
Guide through the through hole 46. This first thread guide
The first upper thread 27a passing through the material 41 is one of the first thread grips.
End face of main body 34a of electromagnet and holding plate in holding means 23
35, and then one of the third thread guide members 43
The driven roller 26a and the driving roller 26a are passed through one of the threading holes.
And the fourth thread guide member 44.
Through one of the threading holes 46 and then the second thread gripping means
24 between the end surface of the body of the electromagnet and the grip plate.
And then the one threading hole 4 of the fifth thread guiding member 45.
6 and then one needle (Fig.
(Not shown). The second thread guide member 42 is a thread winding bobbin.
Thread the second upper thread 27b from
To guide you. The second thread passing through the second thread guide member 42
The upper thread 27b is in the other first thread gripping means 23 '.
Pass between the end face of the electromagnet and the grip plate, and then the third thread
The other driven thread passes through the other threading hole of the guide member 43.
Between the drive roller 25 and the drive roller 25, and then the fourth
It passes through the other threading hole 46 of the thread guiding member 44 and then
Between the end surface of the electromagnet and the grip plate in the second thread grip means 24
The other thread of the fifth thread guide member 45.
The other needle is passed through the hole 46 and then through a balance not shown.
(Not shown). Briefly describing the supply of needle thread,
Without the first and second thread gripping means 23, 23 ', 24, respectively.
Keep the upper thread released and drive roller 25
The driven rollers 26a and 26b grip the upper threads 27a and 27b.
While holding it, rotate the drive roller 25 an appropriate amount and supply to the needle
The predetermined amount of upper thread to be fed is fed out. After this feeding, the first thread
The gripping means 23, 23 'grips the upper thread, and the second thread gripping hand
The upper thread fed out in the state where the step 24 releases the upper thread.
Is sent to the needle by a balance. After this needle thread is sent to the needle,
The second thread gripping means 24 grips the upper thread. by this
Excess needle thread is prevented from being supplied to the needle. Threader
The second frame to give convenience to the first frame
With respect to the direction of arrow Y
Driving means for driving is provided. This drive means
In the embodiment shown, a bracket fixed to the first frame 20
Rotatably mounted on the bracket 46 and this bracket and
Arranged between the first frame 20 and the second frame 21
And an oval-shaped cam 47 that is formed. This cam is
So that it can be rotated manually by the knob 48
Has become. This cam is shown in Fig. 2 when sewing (Fig. 1).
Thus, the short diameter portion 47a has the first frame and the second frame.
It is arranged between the cable and the thread and is shown in Fig. 4 when threading (Fig. 3).
As described above, the long diameter portion 47b has the first frame and the second frame.
Is located between At the time of sewing, as shown in Fig. 1,
The upper thread is a thread guide member, first and second thread gripping means, and
And between the driving roller and the driven roller
It is in a state of From this state, the knob 48 is indicated by an arrow in FIG.
If you rotate it clockwise, the cam 47 will
The second frame 21 is pushed against the compression spring 40 and the first frame 21
The yarn as shown in FIG. 4 by moving it away from the boom 20.
Bring it through. In this state, the needle thread is as shown in Fig. 3.
As described above, the yarn feeding means 22 and the first and second yarn gripping means 2
First to fifth thread guide members separated from 3, 23 'and 24
Only the threading holes 46 of 41 to 45 are passed. In this state
The thread feeding means and the threading means of the first and second thread gripping means.
Can be made easy, especially the knot T on the thread (see Figure 3)
If present, as shown in FIG. 9 and FIG.
Also, threading of the second thread gripping means is facilitated. Thread of Figure 4
From the through state, turn the knob 48 counterclockwise as indicated by the arrow.
When rotated, the cam rotates from the long diameter portion to the short diameter portion,
The second frame 21 is pressed by the compression spring 40.
And approach toward the first frame 20 to sew as shown in FIG.
Can bring to the state. At this time, the upper thread is
The second thread gripping means and the thread delivering means are automatically engaged.
In this way, the needle thread is moved to the first and second positions by operating the knob 48.
Easily engaged with the second yarn gripping means and yarn feeding means
Can be removed. Please refer to FIG. 5 and FIG.
Then, another embodiment of the needle thread feeder according to the present invention is shown.
There is. The needle thread supply device in this embodiment is a needle thread 27a.
Arrangement of a plurality of driven rollers along the feeding direction of (27b)
It was done. In the illustrated embodiment, two driven rollers 5
0 and 50 'are arranged. In addition, this embodiment is not essential
It is not limited to two upper threads, but also applies to one upper thread.
be able to. These driven rollers are the bearings of the lever 51.
It is rotatably supported by 51a. Of this lever 51
The structure is the same as that of the lever 28 except for the bearing portion 51a.
You can Also, the same driven roller driving means is provided.
Has been. In this way, multiple driven rollers feed the upper thread.
If it is arranged in the direction, contact between the driven roller and the drive roller 25
The touching part makes line contact, and
Slip of the upper thread due to the larger contact area compared to point contact
Is drastically reduced. In the embodiment shown in FIG. 5, the driven roller is driven.
Left and right from the center of the drive roller at the upper position of the roller
However, in the embodiment shown in FIG.
One driven roller 50 ′ is arranged almost on the side of the driving roller 25.
It is placed. By doing this, the contact area can be further increased.
Can be large. In this case, the driven roller 5
0 and driven roller 50 'contact the drive roller 25
The pressure of the driven roller 50 ′ is larger than that of the driven roller 50.
small. The driven roller 50 'is located on the side of the drive roller.
As a result, the force component pressed against the drive roller is
This is because it is smaller than 0. In this way the driven roller
By changing the arrangement for the drive roller, each driven roller
The pressing force of the la against the drive roller can be changed.
In the embodiment shown in FIG. 7, the two driven rollers 50, 50 'are
A belt 52 is wound around the periphery. This belt
The driven roller is arranged between the driving roller 25 and the driven roller.
It is pressed against the drive roller by the roller. This practice
In the example, the belt 52 is used for the contact between the driven roller and the driving roller.
Through the line contact, and therefore the contact area is very large
You can do it. 11 and 12 show the empty chain stitching system.
An example of control is shown. That is, the number without sewing
When the needle (about 10 stitches) is sewn, the driven roller drive means
The electromagnet 60 is activated to move the lever 28 against the spring 30.
Drive as shown by the arrow in FIG.
The driven rollers 26a, 26b (or 50, 50 ')
Move away from the drive roller 25. Therefore, the upper thread is not supplied.
Become Such operation is controlled by the control means described later.
It is done voluntarily. In this case, the presence / absence of the sewn product is determined by the cloth detection means.
Detected by 61 (see FIG. 11). This cloth detection hand
The step is, for example, the head end 6 near the needle 62 in the illustrated embodiment.
Needle for mounting the light emitter and the light receiver attached to 3 and the sewing material
It consists of a plate or a reflector attached to the table.
Made up of a light sensor assembly. Incidentally, reference numeral 6
4 shows a presser foot. 13 and 14 show the thickness of the upper thread.
Therefore, when changing the pressing force of the driven roller to the drive roller
Examples of are shown. Upper thread supplying device in this embodiment
The device is a thread thickness detecting means for detecting the thickness of the thread, such as potentiometer.
Of the gyometer 70 (see FIG. 13) and the driven roller driving means.
And a spring force adjusting means 71 for changing the pressure of the spring 30.
There is. This spring force adjusting means is connected to the link 72 and this link.
The eccentric cam 73 arranged so as to come into contact with the eccentric cam
And a motor (not shown) for driving the motor.
The link 72 has a second frame 21 or a sewing machine having a substantially central portion.
It is pivotally attached to the body, and one end of the spring 30 is attached to one end of the body.
Has been. The other end of the link is a cover on the outer circumference of the eccentric cam 73.
Contact the surface. The motor is controlled by the control means described later.
Controlled. The potentiometer mentioned above is also used for this control means.
It is connected. If you put it on easily,
The thread thickness is detected by the target and the motor is controlled accordingly.
It is rotated by the control means, and if the eccentric cam and link
The strength of the bed can be changed. Details will be described later. Figure 1
No. 5 is an example for accelerating the rotation of the drive roller 25 during thread cutting.
An example is shown. The upper thread is cut by thread cutting means (not shown)
To be done. This thread cutting means is, for example, a cutter and this cutter.
It consists of a thread trimming solenoid that drives the motor. this
The thread cutting solenoid is controlled by the control means. Figure 1
As is clear from 5, the motor that drives the drive roller 25
The number of rotations is indicated by the symbol U only when the thread trimming signal C is input.
Is set to be high. Do this
And while the upper thread is present, it is fed out at high speed,
Without affecting it and using more threads than when sewing normally
When you need the thread, you can secure the required amount of thread and
The upper thread can be cut completely and surely. Figure 16 is a needle
The needle thread feeder of the present invention is applied to a sewing machine of a type in which the needle swings.
An example of the case of doing is shown. This needle thread feeder is rocking
Needle bar amplitude detecting means 8 for detecting the swing width of the moving needle bar 80.
1 is provided. This needle bar amplitude detecting means is controlled later.
Connected to the means. This needle bar amplitude detection means
It is attached to the moving table 82. This needle bar amplitude detection means
Output the amplitude of the sewing machine needle as a digital signal.
It FIG. 18 shows an example of the control means 100. In the figure
Reference numeral 101 denotes a sewing machine rotation signal generation circuit, and 10
2 is a stop switch connected to this sewing machine rotation signal generation circuit.
Show the switch. The sewing machine rotation signal generation circuit is rotating the sewing machine.
Signal of "L" is generated when the sewing machine is stopped.
It The stop switch 102 stops the operation of the needle thread feeder.
It has a function to make it. 103 indicates a thread trimming signal generation circuit
However, this circuit is "L" when the thread trimming solenoid is ON,
"H" signal when OFF and this ON → OFF
When "H", OFF → ON, "L" signal and short pulse
Output. The timer 104 is the sewing machine rotation signal generation circuit 1
01, the sewing machine rotation signal
"L" when "L", sewing machine rotation signal is "L" →
When it is switched to "H" and a specified time has elapsed, it becomes "H".
The cloth detection means 61 is connected to the count control circuit 107.
The position detection means 105 is connected to this count control circuit.
Has been continued. If there is a sewn product, the cloth detection means 61
Generates signal "H", and generates signal "L" if none
It The position detecting means 105 includes the upper position, the lower position and
It is for detecting the rotation angle, and the upper and lower positions are being detected.
Respectively generate a signal "L". Count control circuit 107
Is when the cloth detecting means 61 is "L" (when there is no sewing material,
, The upper position, the lower position of the sewing machine or the number of stitches is counted,
When the specified number is counted, the signal becomes "H". Cloth detection hand
When the stage outputs the signal "H", this count control circuit
The signal becomes "L". A lower position setting switch 108 is provided.
This lower position setting switch outputs the lower position signal "H".
Disable with and enable with "L". Reference numeral 109 is a latch
Chi electromagnet position detecting means, which is a latch electromagnet 60.
Rises, that is, separate the driven roller from the drive roller
When operating, output signal is "L", when falling, ie driven low
When the roller is pressed by the drive roller, "H" is output. La
The electromagnet 60 has an ascending operation circuit 110 and a descending operation circuit.
111 is connected. In addition, these raising operation circuits and
And a reset signal generating circuit 112 is connected to the descent operation circuit.
Has been done. Ascending actuation circuit 110 has latch electromagnet 60
The timer 104 and thread trimming signal generation circuit 103
ON → OFF signal, stop switch 102, count control
Depending on the "L" → "H" signal of any of the circuits 107,
The electromagnet 60 is lifted. Also, the reset signal generation
A reset signal from the path 112 unconditionally latches the electromagnetic
Raise the stone. The lowering operation circuit 111 has a latch electromagnet
When rising, the sewing machine rotation signal of the sewing machine rotation signal generation circuit 101
Signal causes the latch electromagnet to descend. Reset signal input
Sometimes it doesn't work. The latch electromagnet 60 is as described above.
When driven, the driven rollers 26a, 26b (50, 50 ') are raised.
To lower the driven roller when descending. Reset signal
The signal generation circuit 112 is a reset signal when the power is turned on and off.
To occur. The sewing machine speed detecting means 113 is provided,
The detection means detects the speed of the sewing machine and
And output the frequency. Feeding setting means 114 and feeding
And a detection unit 115 is provided, and the feeding setting unit 114 is provided.
Is connected to the latch circuits 116 and 117 to detect the feeding.
A counter circuit 118 is connected to the means 115.
The feeding setting means 114 keeps the driven rollers 26a, 2 during sewing.
Setting of the amount of thread feeding of the two upper threads of 6b and the two at the time of thread cutting
Set the thread feed amount of the upper thread. Feeding detection means 115
Outputs the yarn feeding amount by a digital pulse. Latch times
The path 116 is a rotation angle detection output from the position detection means 106.
During sewing between the rotation angle specified by the intelligent signal
Latch the thread feeding setting of. The other latch circuit 1
17 is a thread trimming signal generating circuit 103 and a thread trimming solenoid
OFF → ON signal to set the thread take-up amount during thread cutting
To latch. The counter circuit 118 is the feeding detection means 11.
The digital pulse generated in 5 is counted and output.
Further, the count clear is the rotation angle of the position detection means 106.
It is performed at a specified angle. Pitch detection means 119 is provided
This pitch detecting means detects the pitch of the sewing machine and
Output with digital signal. This pitch detection means has an error
The arithmetic circuit 120 is connected. Also, this error calculation circuit
Are connected to the latch circuit 116. Needle bar amplitude above
The detection means 81 is connected to this arithmetic circuit 120.
The error calculation circuit 120 outputs from the sewing machine speed detecting means 113.
The detection signal, the latched setting signal of the latch circuit 116,
Pitch detection output of pitch detection means 119, needle bar amplitude detection
The feeding amount is calculated by the output of the means 81 and is output. Mistake
Selectable for the difference calculation circuit 120 and the latch circuits 116 and 117.
The selection circuit 121 is connected. This selection circuit is thread trimmer
Latch when the thread cutting signal of the signal generating circuit 103 is "L"
Output the latched design quantity of the circuit 117,
Output the error calculation circuit output. In the selection circuit 121
The comparators 122 and 123 are connected and these comparators 12
Reference numerals 2 and 123 are connected to the counter circuit 118. ratio
The comparator 122 outputs the output of the counter circuit 118 and the selection circuit 12
1 and R side output is compared, and when they are the same, signal "L"
Is output. The comparator 123 outputs the counter circuit 118.
And the L-side output of the selection circuit 121 are compared and found to be the same.
At this time, the signal "L" is output. Reference numeral 126 is a first R electromagnet
And 127 is the first L electromagnet. The first R electromagnet
The voltage of one of the two first thread gripping means is
The first L electromagnet corresponds to the magnet, and the first L electromagnet is the electromagnetic of the other yarn gripping means.
Equivalent to stone. The first R electromagnet 126 has an operating circuit 124.
Is connected, and the operating circuit 125 is connected to the first electromagnet 127.
Has been continued. These operating circuits 124 and 125 are reset
Connected to the output signal generation circuit 113. Operating circuit 12
4 turns on the first R electromagnet when "H" is input, and when "L" is input
Turns off. It is turned on when the reset signal is input. Product
The driving circuit 125 turns on the first L electromagnet when "H" is input,
Turns off when "L" is input. Also, when the reset signal is input
Turns on. Incidentally, the first R electromagnet 126 is one of the two needles.
For example, controlling the yarn feeding of the right needle, the first L electromagnet 127
Controls the thread delivery of the left needle. The electric power of the second thread gripping means 24
A second electromagnet control circuit 128 for controlling the magnet is provided,
An operating circuit 129 is connected to this circuit.
A second electromagnet 130 is connected to. This second electromagnetic
The stone corresponds to the electromagnet of the second thread gripping means. This second electric
As described above, the magnet holds the thread when it is ON and releases it when it is OFF.
It The second electromagnet control circuit is provided by the position detecting means 106.
The position detecting means 1 outputs "H" according to the determined rotation angle.
Set rotation angle signal and thread trimming signal generation circuit from 06
Thread cutting signal from 103, latch electromagnet position detecting means 1
09 signal or stop switch 102 signal
The output "L" is generated by any of these signals. Operating circuit 12
9 turns on the second electromagnet 130 by inputting “H”,
This is turned off by inputting "L". Reset signal input
The time is ON. One-needle setting switch 131, thread breakage detection
Means 132 and linear motor position detection means 133 are provided
Has been. In addition, the single needle setting switch 131 and the linear model
The operating circuit 134 is connected to the data position detecting means 133,
A linear motor 135 is connected to this operating circuit.
This linear motor is an actuator (not shown) that controls one needle.
Operates the ETA to neutral / left / right positions. One needle installation
The constant switch stops sewing in the one-needle control sewing machine.
It is a switch for inputting the needle bar.
Stop input "L" will be a stop input. Thread breakage detection means 13
No. 2 detects a thread break and sets the output to "L".
In the case of, the output is set to "H". Linear motor position detection
The means 133 detects the position of the linear motor 135 and detects the voltage
Output as data. The operating circuit 134 is a linear motor
Upon receiving the signal from the placement detecting means 133, the linear motor 135 is driven.
Operate left and right. First R electromagnet 1 of the first thread gripping means
26 and the first L electromagnet 127 for controlling the first electric
A magnet control circuit 136 is provided. This first electromagnet
The control circuit uses the signal of the stop switch 102 and the latch electromagnet position.
The signal from the position detecting means 109 and the signal from the position detecting means 106
Turning angle signal / thread trimming signal generation circuit 103 turns OFF → O
"L" is output by either of the N signals. Also, comparator
Receiving "L" signals from 122 and 123 and outputting "H"
It Thread trimming signal generation circuit 103, stop switch 102 and
And the frequency generating circuit 137 is connected to the feeding setting means 114.
Has been done. Further, DC motor rotation speed detection means 138 is provided.
The DC motor rotation speed detecting means is provided with a comparator 139.
Is connected to this comparator, and a motor control drive circuit 1 is connected to this comparator.
40 is connected, and DC is connected to this motor control drive circuit.
The motor 141 is connected. This DC motor is driven
It corresponds to a motor that drives the roller 25. Frequency generation frequency
The path 137 is a thread trimming signal of the thread trimming signal generating circuit 103
The data of the output setting means 114 and the stop switch 102
Generates the frequency required to rotate the DC motor 141 by input
To live. The DC motor rotation speed detecting means 138 is a DC motor.
The frequency of 141 is output as the frequency of the digital pulse. ratio
The comparator 139 rotates the frequency generating circuit 137 and the DC motor.
The input from the detection means 138 is compared, and the detection means 138
The input value from the input circuit is lower than the input value from the generation circuit 137.
"H" is output when it becomes, and "L" is output when the opposite occurs.
It When the motor control drive circuit 140 is “H” input
When the rotation of the DC motor 141 is accelerated to "L" input
Slows down. Position of the presser foot for pressing the sewing material of the sewing machine
The presser foot detecting means 142 for detecting the position is provided.
The output means is "L" when the presser foot is rising, and the presser foot is
When descending, that is, in the state of holding down the sewing
Output "H". Generating a false signal to the selection circuit 121
The circuit 143 is connected, and this false signal generation circuit
Generate "L" or "H" signal, and use "L"
Done. The thread feeding means 22 is used so that normal sewing is performed at "H".
To control. The division number setting means 144 and connected to this
The division circuit 145 is provided. In this division circuit
Is connected to a comparator 146, to which the distributor 14
7 is connected. The division number setting means 144 is the division number
The division ratio of the path 145 is determined. Also, a stop command with a division ratio of ∞
Can be set. The division circuit 145 is a one-needle setting switch.
When R is “L” at the input of switch 131, R is divided and output
If L is "L", L is divided and output. The division rate is
It is determined by the input of the division number setting means 144. The division rate ∞
Not output when. The comparator 146 is the counter circuit 118.
If the output and the output of the division circuit 145 are compared and they are the same,
Output "L". The distributor 147 has a configuration as shown in Table 1.
Has been A one-needle limiting circuit 148 is provided,
When the one-needle setting switch 131 is input,
It works to limit the salary. Referring again to FIG. 16, the needle
The case of controlling the upper thread take-up amount according to the swing width
Describe. The delivery setting means 114 controls the yarn delivery means 22.
And set the yarn feeding amount. This feeding setting means 114
A correction means 150 is connected to the
151 is connected, and a pitch amount setting means is connected to this comparator.
152 and needle thread supply setting switch 153 are connected
It Further, the comparator 151 has a needle bar amplitude detecting means 81.
It is connected. Therefore, by the needle bar amplitude detection means 81
A signal indicating the amount of the upper thread fed out according to the amplitude of the needle is output to the comparator 151 and
It is given to the feeding setting means 114 via the correcting means 150.
be able to. The rotation setting means 1 is provided in the feeding setting means 114.
DC motor through 60 and motor drive control means 161
By connecting 141, rotation of the drive roller 25
Can be changed stepwise according to the needle feed pitch
It When the power of the sewing machine is turned on or off,
The upper thread is gripped by turning on the electromagnet of the second thread gripping means.
The circuit is the operating circuit 1 in the control means shown in FIG.
24, 125, first R electromagnet 126, first L electromagnet 12
7, an operating circuit 129 and a second electromagnet 130.
When the power of the sewing machine is turned on or off, the driven low
The circuit that separates the rollers 26a and 26b from the drive roller 25 rises.
Actuation circuit 110, descending actuation circuit 111 and latch electromagnet
It consists of 60. These circuits enable the sewing machine to start or stop.
There is a real benefit that the upper thread is not supplied excessively when stopped.
The single needle operation will be described again. As shown in FIG.
When sewing the collar 150 of clothes with two needles, the sewing
In l₁Sewing line l of the other needle than (inner)₁(Outside
Side) is longer. Therefore, in this case, the sewing line l_Twoof
The sewing line l₁Have to send the upper thread more than
No In the needle thread feeder of the present invention, the sewing line 1₁On
Leave the driven roller that sends the yarn away from the drive roller for a certain period of time.
Sewing line l_TwoIt is possible to reduce the amount of thread
it can. This is a latch electromagnet that drives this driven roller
Is done by controlling. Also, the sewing line l₁
The first thread gripping means related to_TwoRelated to
The thread grip timing earlier than the first thread grip means
The sewing line l₁Thread feeding
Amount of sewing line l_TwoCan be less than.
Further, in the needle thread feeder of the present invention, the presser foot is raised during sewing.
Even if the driven roller and the drive roller remain engaged, that is, the thread
It can be held in the feeding state. This is the presser foot detection
Means 142 and the first electromagnet control circuit 136,
This can be done by setting the state. Ise again
The function of the stitches will be described. Busy signal generation circuit
Numeral 143 is a delivery setting means 11 for controlling the yarn delivery means 22.
4 and the first electromagnet control circuit 136 to control the yarn feeding
Set the amount less than the desired dispense amount. This is the first
The first R electromagnet 126 and the first L electromagnet are controlled by the electromagnet control circuit.
Hold the thread with magnet 127 earlier than normal timing
Control so that the thread feeding amount is reduced.
It When the thread take-out amount becomes small, the thread pulls the sewing product,
The sewn product is squeezed. This is how to sew
You can do

According to the present invention, the upper yarn can be reliably and accurately supplied by the above-mentioned structure, and various upper yarn supply control can be performed by the control means. There is a real advantage that it is possible to provide a superior needle thread feeder.

[Brief description of drawings]

FIG. 1 is a perspective view showing a sewing state of a needle thread feeder according to the present invention,

2 is a bottom view of FIG. 1,

FIG. 3 is a perspective view of the device of FIG. 1 showing a threading state,

4 is a bottom view of FIG. 3,

FIG. 5 is a front view of the main part showing an embodiment in which a plurality of driven rollers are arranged along the yarn feeding direction,

FIG. 6 is a front view of a main part showing a modified example of FIG. 5;

FIG. 7 is a front view of a main part showing still another modified example of FIG.

FIG. 8 is a side view showing a modified example of the arrangement of driven rollers.

FIG. 9 is a side view showing the knot of the thread during sewing just before passing through the thread gripping means;

FIG. 10 is a side view showing the thread guiding member in a threading state separated from the thread gripping means;

FIG. 11 is a side view of a main part of the sewing machine head to which the cloth detecting means is attached,

FIG. 12 is a front view showing an embodiment in which an idler driven roller is separated from a drive roller;

FIG. 13 is a top view of a thread thickness detecting means for detecting the thread thickness,

FIG. 14 is a schematic configuration diagram showing a spring force adjusting means,

FIG. 15 is a graph showing a rise in rotation of the drive roller motor during thread cutting;

FIG. 16 is a schematic configuration diagram showing the arrangement of a needle bar amplitude detection means and a needle,

FIG. 17 is a plan view of a collar portion of a sewn item sewn with two needles.

FIG. 18 is a schematic configuration diagram of control means,

FIG. 19 is a table showing the functions of the distributor,

FIG. 20 is a schematic configuration diagram of a conventional needle thread feeder.

FIG. 21 is a side view of a conventional driven roller.

[Explanation of symbols]

 20 first frame 21 second frame 22 thread feeding means 23, 23 'first thread gripping means 24 second thread gripping means 25 drive rollers 26a, 26b driven rollers 27a, 27b needle thread 28 lever 30 spring 60 latch Electromagnet 100 control means

Claims (1)

[Claims] 1. A first and a second frame, a yarn feeding means attached to the first frame, and a first yarn attached to the first frame, which is arranged in front of the yarn feeding means. The gripping means, the second thread gripping means arranged in the subsequent stage of the thread feeding means and attached to the first frame, the first thread gripping means, the thread feeding means and the second thread gripping means. A plurality of thread guiding members arranged in the thread path passing therethrough and attached to the second frame, wherein the second thread guiding members are arranged in the thread path or are separated from the thread path. The upper thread feeding device is characterized in that the frame is movable with respect to the first frame.