JPS6142591B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an industrial pattern stitch sewing machine, and more particularly to an industrial pattern stitch sewing machine that feeds cloth in a plane using a pulse motor based on a pattern stored in a memory in advance.

Pattern stitch sewing machines can perform predetermined pattern stitches accurately and quickly, and are therefore useful for improving work efficiency in sewing processes. A sewing machine that performs sewing based on a plurality of patterns such as embroidery patterns stored in advance in its memory can easily select any one of the plurality of pattern patterns stored in its memory. You can select more patterns by changing the memory contents or replacing it with another memory.
Alternatively, the selected pattern has many useful features, such as being able to be enlarged or reduced freely for sewing.

However, in this type of sewing machine, the actual feed amount of the presser foot, which is flat-fed while clamping the cloth on the sewing machine table, may not reach the feed command value due to a step-out in the pulse motor, etc. If the error between the actual feed amount and the feed command value becomes extreme, there is a risk that the presser foot will exceed the feed limit range allowed for the presser foot. For this reason, in conventional sewing machines, accidents such as collision between the sewing machine needle and the presser foot may occur, which is dangerous. Such accidents generally occur when sewing is performed that enlarges the pattern. Further, in this type of sewing machine, the pulse motor often loses synchronization during the enlarged sewing.
In other words, when sewing an enlarged pattern, the amount of cloth feed increases and the speed of the pulse motor increases, but the torque of the pulse motor decreases rapidly as the speed increases, making it difficult to drive the presser foot with the pulse motor. As a result, the pulse motor loses synchronization.

The present invention has been made in view of the above-mentioned conventional problems, and its purpose is to provide an industrial pattern stitch sewing machine that stops the sewing machine operation when the presser foot exceeds the feed limit range allowed for the presser foot. There is a particular thing.

In order to achieve the above object, the present invention provides a sewing machine body that sews a predetermined pattern while flatly feeding a presser foot holding a cloth on a sewing machine table using two pulse motors, and a sewing machine that stores a predetermined pattern pattern. The sewing machine has a memory, an operation command section that includes a plurality of command elements that output operation commands including an enlargement command, and a sewing machine control section that reads out a pattern from the memory and controls the sewing machine body according to the operation command. In an industrial pattern sewing machine that can sew, a rotation detection plate that is installed on the rotation shaft of each pulse motor and rotates with each rotation shaft is used to detect when the feed limit range allowed for the presser foot is exceeded. A feed limit detector that outputs a feed limit detection signal by rotation of the plate, a rotating disk provided on the rotating shaft of each pulse motor, and a detector that cooperates with the rotating disk, which is used to detect enlarged commands. The invention is characterized in that it is provided with an origin detector that outputs origin detection signals in both the X-axis and Y-axis directions serving as a pattern origin reference, and that the sewing machine control section controls the sewing machine body to stop based on the feed limit detection signal.

Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

A preferred embodiment of the invention is shown in FIGS. 1, 2, and 3. FIG. 1 shows an outline of this embodiment, and this embodiment consists of a sewing machine body 10 that performs pattern stitching, a P-ROM 12 that stores various sewing patterns, and an operation command that outputs operation commands. 14, and a sewing machine control section 16 which reads the pattern from the P-ROM 12 and controls the sewing machine main body 10 based on operation commands.

As shown in FIG. 2, in the sewing machine main body 10,
A cloth to be pattern sewn is held between an upper presser foot 20 and a lower presser foot 22 of a cloth presser foot 18 on a sewing machine table. In the figure, the presser foot 18 is fed in the X-axis direction by a pulse motor 24 via a feed transmission mechanism 28 including a drive belt 26, and by a pulse motor 30 via a feed transfer mechanism 34 including a drive belt 32. It is sent in the Y-axis direction.

Further, the sewing machine main shaft of the sewing machine body 10 is driven by a drive motor 36, and embroidery is performed on the cloth held by the presser foot 18.

Furthermore, Fig. 1 shows the presser foot drive, thread splitting,
Electromagnets 38 for thread cutting, thread removal, and thread loosening,
40, 42, 44, and 46 are shown, and when each is driven, the fabric is released from or clamped from the presser foot 18, or the thread is split, thread trimmed, thread wiped, or thread loosened.

Next, the operation command section 14 will be explained. The driving command section 14 is provided with a plurality of command elements for outputting various driving commands.

The first and second command elements are photo interrupters 48 and 50 that output operation commands 100 and 102 in conjunction with a foot pedal (not shown).
In this device, the photo interrupter 48 outputs a command 100 to raise the upper presser 20 when the foot pedal is not depressed, and to lower the upper presser 20 to clamp the fabric when the foot pedal is lightly depressed. When the pedal is depressed more deeply, a start command 102 to start the sewing machine operation is output from the interrupter 50.

In this device, it is possible to select any one of a plurality of pattern patterns stored in advance in the P-ROM 12 and perform pattern sewing, but a third command element is provided for selecting this pattern pattern. ing. That is, in FIG. 1, a pattern selection circuit 52 having a plurality of switches is provided as a third command element, and by operating a switch of the pattern selection circuit 52, one of the pattern patterns stored in the P-ROM 12 is selected. A selection command 104 to select is output.

Further, in this device, the sewing machine speed can be switched and set in several stages, and a fourth command element is provided to command the sewing machine speed. That is, the first
In the figure, a sewing machine speed command circuit 54 having a plurality of switches is provided as a fourth command element, and a predetermined sewing machine speed is selected by a speed selection command 106 outputted by switch operation of the sewing machine speed command circuit 54. be done.

Further, this device can sew by enlarging or reducing the pattern, and includes fifth and sixth command elements for instructing the enlargement or reduction of the pattern. That is, FIG. 1 shows a fifth switch having a plurality of switches,
Enlargement/reduction command circuit 56 as a sixth command element,
58, and by operating the switches of each command circuit 56, 58, the command circuit 56 issues a command 108 to enlarge or reduce the pattern in the X-axis direction, and the command circuit 58 issues a command 108 to enlarge or reduce the pattern in the Y-axis direction. Command 1 for enlarging or reducing
10 are output respectively. This device can form a pattern that is enlarged or reduced in the X-axis direction or the Y-axis direction by the pattern enlargement/reduction commands 108 and 110.

The operation command unit 14 of this embodiment has the above configuration. In addition, in FIG. 1, an interrupter 60, which detects the pattern origin in the X-axis direction and the Y-axis direction,
62 are shown adjacent. In this device, two rotating disks are provided on the rotating shafts of the pulse motors 24 and 30, as shown by the chain lines in FIG. Photo interrupters 60 and 6 are provided as reference numerals 25 and 31 and correspond to the notches of each rotating disk.
2 are arranged, and when the notch of each rotating disk reaches the slit of the photo interrupter 60, 62, the origin detection signal 11 in the X-axis direction and the Y-axis direction is generated.
2,114 is output as the pattern origin reference for the enlargement command.

Next, the sewing machine control section 16 that drives and controls the sewing machine main body 10 will be explained.

In FIG. 1, the sewing machine control section 16 includes a CPU 6 that controls the sewing machine main body 10 by performing various calculations based on various operation commands from the operation command section 14.
4, and a RAM is provided for the calculations of this CPU 64. In addition, the input port 70 is shown in FIG.
and output port 72 are shown, and the aforementioned operation commands 100, 102, 104, 106, 108,
110 and origin detection signals 112 and 114 are taken into the sewing machine control section 16 via the input port 70, and various control signals from the CPU 64 are outputted from the output port 72.

The sewing machine control unit 16 controls the sewing machine main body 1 according to the control signal output from the output port 72 as follows.
Drive control of 0.

Electromagnet 3 for the presser foot of the sewing machine main body 10 described above
8, Thread splitting electromagnet 40, Thread cutting electromagnet 42,
The thread removing electromagnet 44 and the thread loosening electromagnet 46 are
Each control signal 116, 118, 120, 122, 1
24 are each supplied with amplifiers 74, 76, 78,
The drive is controlled by 80 and 82. For example, when the foot pedal is operated, the command 100 is sent to the sewing machine control section 1.
6, the control signal 116 is applied from the output port 72 to the amplifier 74, the amplifier 74 drives the electromagnet 38, and the upper presser 20 is controlled by the command 10.
The fabric is raised and lowered in accordance with 0, and the fabric is released from the presser foot 18 or is clamped by the presser foot 18.

Further, the drive motor 36 of the sewing machine main body 10 is driven and controlled by an amplifier 84 to which a control signal 126 is applied from the output port 72. In this embodiment, when the foot pedal is depressed deeply and the command 102 is taken into the sewing machine control section 16 through the input port 70, the control signal 126 is applied to the amplifier 84 to drive the drive motor 36, which drives the sewing machine main body. The main shaft of the sewing machine No. 10 rotates to perform sewing.
The speed of the drive motor 36 is set to a constant speed that is preselected by operating a switch in the speed command circuit 54. In this embodiment, the speed detection signal 12 of the speed detector provided in the sewing machine body 10 is
8 is supplied to the sewing machine control section 16, and the speed of the drive motor 36 is controlled by the sewing machine control section 16 so as to be at a preselected speed.
Further, the sewing machine main body 10 is provided with a needle position detector for detecting the position of the sewing machine needle, and a needle position detection signal 130 thereof is supplied to the sewing machine control section 16. This needle position detection signal 130 is used to adjust the timing so that the fabric is not fed when the sewing machine needle is piercing the fabric, or to ensure that the sewing machine needle is not piercing the fabric when cutting thread. The signal is used in the sewing machine control section 16 as a signal necessary for controlling the sewing machine.

Furthermore, as described above, this apparatus performs pattern stitching while feeding the cloth in a plane using the pulse motors 24 and 30, and the drive control of the pulse motors 24 and 30 is performed in the following manner.

In the sewing machine control unit 16, a pattern selection command 104, a speed command 106, a pattern enlargement/reduction command 108, 1
10 is fetched and the start command 102 is fetched, the sewing machine control section 16 controls the drive motor 36.
is driven at a speed according to the speed command 106 to move the sewing machine needle up and down, and when the sewing machine needle is retracted upward, the pulse motors 24 and 30 are driven to move the presser foot 1.
8 is plane-feeded. That is, the CPU 64
- Read the feed amount for one stitch of the pattern selected by the pattern selection command 104 from the ROM 12, and enlarge/reduce this feed amount with commands 108, 110
The parallel pulse data 132 (for the X-axis direction) and 134 (for the Y-axis direction) corresponding to the expanded/reduced feed amount are expanded/reduced in the X-axis direction and the Y-axis direction by
The pulse generation circuit 8 sends the pulse through the output port 72.
Output to 6. Then, the sending pulse generation circuit 86
The speed detection signal 128 converts parallel pulse data 132 and 134 into serial pulse data 1 according to the sewing machine speed only when the sewing machine needle is retracted upward.
36,138 and output to amplifiers 88,90. As a result, the number of cloth feeding drive pulses 136 corresponding to the enlarged or reduced pattern pattern is transmitted from the amplifiers 88 and 90 to each pulse motor 24 and 30.
a, 138a are output according to the sewing machine speed, and each pulse motor 24, 30 rotates to
Fabric feeding is performed in a plane. Therefore,
A uniform stitch pattern is formed on the cloth plane-fed by the presser foot 18 at a predetermined magnification or reduction ratio, regardless of the speed of the sewing machine.

By the way, as mentioned above, an object of the present invention is to provide a sewing machine that stops the sewing machine operation when the presser foot exceeds its feed limit area. A feed limit detector is provided to detect the feed limit detection signal, and the sewing machine control section controls the sewing machine to stop based on the feed limit detection signal.In order to realize the present invention, this embodiment is configured as follows. ing.

In this embodiment, in order to detect that the feed limit area allowed for the presser foot 18 has been exceeded, the pulse motors are fixed to the rotating shafts of the respective pulse motors 24 and 30 on the side opposite to the drive side of the presser foot 18. rotation detection plate 9
2 and 94, and limit detectors 96 and 98 that output feed limit detection signals 140 and 142 based on the rotation angle of each rotation detection plate 92 and 94, and these constitute a feed limit detector. Figure 3 explains the configuration of this feed limit detector.
Figure A shows the front side of the feed limit detector, Figure B shows its side view, and Figure C shows its electric circuit.

In FIG. 3, the rotation detection plates 92 and 94 are the rotation shafts of the pulse motors 24 and 30, and are the rotation shafts of the presser foot 18.
The limit detectors 96 and 98, which are fitted into the rotating shaft on the opposite side to the drive side and are fixed with screws, and are constituted by photo interrupters, are fixed with screws to the sewing machine body 10. Further, half of the outer periphery of the rotation detection plates 92, 94 is cut out in an arc shape, and the uncut outer periphery is used for the pulse motors 24, 3.
0 rotation allows light to pass through the slits of photointerrupters (limit detectors) 96, 98 and to be applied from the light emitting diode to the phototransistor. In this embodiment, when the uncut outer peripheral portions of the rotation detection plates 92 and 94 are moving within the slits of the photo interrupters (limit detectors) 96 and 98, the presser foot 18 is moved in the X direction or the Y direction. The feed limit detection signals 140 and 142 are not outputted within the limit range, and the uncut outer circumferential portions of the rotation detection plates 92 and 94 pass through the slits and the presser foot 18
When exceeds the feed limit area in the X direction or Y direction, the light from the light emitting diodes of the photo interrupters 96 and 98 passes through the slit and hits the photo transistor, thereby generating the feed limit detection signal 1.
40 or 142 is output. The feed limit detection signals 140, 142 are supplied to the input port 70, and the sewing machine control unit 16 controls the sewing machine body 10 to stop when either one of the feed limit detection signals 140, 142 is supplied. I can do it.

As understood from the above explanation, the rotation range of the pulse motors 24 and 30 is only allowed to rotate by 180 degrees due to the feed limit range of the presser foot 18. This is because this range of rotation is considered sufficient considering the shape and dimensions of the pattern formed on the cloth.

A preferred embodiment of the present invention has the above configuration,
The operation will be explained below using the flow diagram shown in FIG.

First, the power is turned on and the sewing machine control section 16 is initial reset. Along with this, the origin detection signal 1
12, 114 are given to the sewing machine control section 16 and X
The presser foot 18 moves to the pattern origin in the axial direction, and
The presser foot 18 moves to the pattern origin in the axial direction, and as a result, the presser foot 18 is guided to the pattern origin on the XY plane. Then, the fabric is placed on the lower presser foot 22,
When the foot pedal is depressed lightly, the cloth is clamped by the upper presser foot 20.

Next, the "signal input" shown in FIG. 4 is performed. That is, the commands 108 and 110 to enlarge or reduce the pattern in the X-axis direction and the Y-axis direction are selected by the enlargement/reduction command circuits 56 and 58, and the speed command 106 is selected by the speed command circuit 54, Furthermore, P
- A pattern selection command 104 for selecting a predetermined pattern in the ROM 12 is selected by the pattern selection circuit 52 and supplied to each input port 70.

Next, when the foot pedal is depressed further, the sewing machine control section 16 outputs a feed limit detection signal 14.
After confirming that 0 and 142 are not input (both the feed limit detection signals 140 and 142 are not input since the presser foot 18 is at the pattern origin at the start), the drive motor 36 is started using the control signal 126. The sewing machine 10 starts to be driven. Then, only once when the sewing machine needle comes under the fabric, the sewing machine control unit 16 reads one unit corresponding to one stitch in the pattern pattern selected by the command 104 from the P-ROM 12, and uses the speed command 106 and the pattern. According to the speed command 106 and the enlargement/reduction commands 108, 110, the presser foot 18 is moved in a plane on the sewing machine table by driving and controlling the pulse motors 24, 30 while controlling the drive motor 36. Then, one unit of the pattern enlarged or reduced in the X-axis direction, Y-axis direction, or both directions is applied to the fabric held by the presser foot 18, and the sewing machine body 10
to form.

Furthermore, the process returns to the "signal input" shown in FIG. 4, and the next time the needle comes under the cloth, the same operation is repeated.

As a result, an enlarged or reduced pattern is formed on the cloth held by the presser foot 18 for each unit (one stitch).

During the above operation, the pulse motors 24, 3
0 is out of step and as a result, when the presser foot 18 is fed beyond its feed limit area, the sewing machine main body 10 is controlled to stop, and the sewing machine needle and presser foot 18
Collision with is avoided.

That is, the presser foot 18 exceeds its feed limit area, and the cutout outer circumference of either of the rotation detection plates 92, 94 in FIG. When either limit detection signal 140 or 142 is output, sewing machine control section 16 outputs feed limit detection signal 1.
40 and 142, it is determined that the presser foot 18 has exceeded its allowable feed limit area, and the sewing machine main body 10 is controlled to stop.

As explained above, according to the present invention, the sewing machine is controlled to stop when the presser foot exceeds the feed limit range allowed for the presser foot, so collisions between the sewing machine needle and the presser frame can be effectively prevented. can be avoided. Therefore, according to the present invention, it is possible to construct a safe pattern sewing machine in which collision between the sewing machine needle and the presser frame does not occur.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a preferred schematic configuration of the present invention, FIG. 2 is an explanatory diagram of the cloth feeding mechanism of FIG. 1, and FIG.
FIG. 1 is an explanatory diagram of the configuration of the feed limit detector, and FIG. 4 is a flow diagram of a preferred embodiment of the present invention. The same parts in each figure are given the same reference numerals, 10 is the sewing machine body, 12 is the P-ROM, 14 is the operation command section, 16 is the sewing machine control section, 18 is the presser foot, 24,
30 is a pulse motor, 36 is a drive motor, 52 is a pattern selection circuit, 54 is a speed command circuit, 56, 58
is an enlargement/reduction command circuit, 92 and 94 are rotation detection plates,
96 and 98 are limit detectors.

Claims (1)

[Claims] 1 The main body of the sewing machine, which sews a predetermined pattern while feeding the presser foot that holds the cloth between the two on the machine table using two pulse motors, a memory that stores the predetermined pattern pattern, and outputs operation commands including enlargement commands. An industrial pattern stitch sewing machine capable of enlarging stitches, which has an operation command unit equipped with a plurality of command elements to perform enlarged stitching, and a sewing machine control unit that reads a pattern from the memory and controls the sewing machine main body according to the operation command. In order to detect when the feed limit area allowed for the presser foot is exceeded, a rotation detection plate is installed on the rotation shaft of each pulse motor and rotates with each rotation shaft, and a feed limit detection signal is output by the rotation of each rotation detection plate. A feed limit detector having a feed limit detector, a rotating disk provided on the rotating shaft of each pulse motor, and a detector that cooperates with the rotating disk and the X-axis and Y-axis directions that serve as the pattern origin reference for the enlargement command. An industrial pattern stitch sewing machine, comprising: an origin detector that outputs both origin detection signals; and a sewing machine control section that controls the sewing machine to stop based on the feed limit detection signal.