JPS6042731B2 - Cloth detection sewing control sewing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sewing machine, and more particularly to an automatically activated sewing machine that is equipped with a cloth detecting means and uses cloth detection as a condition for starting sewing in a certain mode of sewing control.

Conventional sewing machines are generally equipped with a switch that detects the depression of a foot pedal, and a potentiometer or encoder that indicates the amount of pedal depression, so that sewing is started in response to the pedal depression, and the sewing speed is determined according to the amount of depression. ing.

Recently, there has been a trend to construct electronic control devices by assembling electronic elements such as ICs, LSIs, and microcomputers, and to perform control operations in a sophisticated manner and in a wide variety of ways. Although I am calm,
Sewing efficiency and ease of sewing work have not been improved much. A sewing machine with improved work efficiency and simple work is desired, especially in industries where the same or similar patterns are repeatedly sewn at high speed. It is desired to improve work efficiency and simplify work in commercial sewing machines.

A first object of the present invention is to provide a sewing machine that improves work efficiency, and a second object is to provide a sewing machine that simplifies work.

In order to achieve the above object, the present invention provides a sewing machine equipped with a foot pedal and an electronic control device that controls sewing according to the pedal's depression.A cloth detection means is installed at the tip of the sewing machine arm, and the cloth detection information is electronically transmitted. The electronic control device is configured to start sewing in at least one sewing control mode on the condition that at least the pedal is depressed and the presence of cloth is detected.

That is, when the cloth detecting means detects cloth while the foot pedal is being depressed, the sewing machine starts sewing. The cloth detection means detects when cloth arrives at a certain position, no matter what it is, so in some cases, sewing may be started even when there is not enough cloth set. Even in the worker's normal cloth setting work, it is preferable that sewing is started after the worker considers that the cloth setting is completed. Therefore, in the present invention, the electronic control device is further configured to measure time, and starts counting when the presence of cloth is detected after the pedal is depressed, and starts sewing after a predetermined time. Furthermore, depending on the sewing pattern, the type and size of the fabric, the planned sewing speed, or the operator, the time from when the fabric detection means detects the fabric until the start of sewing can be set by the operator as appropriate. Preferably, it can be set. Accordingly, the present invention is further configured such that the electronic control device reads the set value of the time setting means which can be set manually, starts timing, and then starts sewing after the set time has elapsed. Although a microswitch or a photo sensor can be used as the cloth detection means, it is preferable to use a photo sensor from the viewpoint of ease of arrangement and reliability of detection.Also, even with a photo sensor, the space around the needle should be taken up as little as possible. It is preferable to use a reflective photosensor and form a reflective surface around the needle. Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1a is a needle perspective view showing an outline of the appearance of a sewing machine embodying the present invention.

In FIG. 1a, a sewing machine bed 12 is pivotally mounted to a sewing machine table 10 so as to be tiltable. sewing machine bed 1
A standard 14 is integrally formed perpendicularly to the sewing machine 2, and a sewing machine arm 16 is integrally formed with the standard 14 in a substantially perpendicular relationship. A sewing machine motor M is installed at the bottom of the table 10, and a clutch and brake unit 18 is coupled to this motor M.
a pulley fixed to the output shaft of the arm 16, and one end of the arm 16.
A belt is stretched around a pulley 20 fixed to the upper shaft. Mounted below the motor M is a motor control box 22 with one end of a link coupled to a pedal 24 driving a pedal switch and potentiometer within the box 22. table 1
0, a sewing control box 26 is fixed to the front of the unit 18, and a power on switch button 2 is attached to the right side of the sewing control box 26.
8. A power off switch button 30 and a presser foot lifting solenoid unit 100 are arranged. The front side of the sewing control box 26 is shown in FIG. 1b. The box 26 is equipped with an electric unit and control setting switches for performing various conventional sewing controls.Firstly, to explain what is conventionally provided, the box 32f is a one-stitch (one-stitch) for forward sewing.
32b is a dial that sets the sewing length (Tfrm) for 1 stitch of backward stitching, 34f is a dial that sets the sewing length for one stitch of backward stitching, and 34f is a dial that sets the sewing length for one stitch (single) and 2 A changeover switch 34b sets the sewing speed at the beginning of sewing to either one reciprocation (double), a changeover switch 34b sets the folding stitch at the end of sewing to one reciprocation or two reciprocations, and 36 changes the sewing speed at the beginning of sewing to a predetermined number of stitches (number of stitches). ), and a speed corresponding to the amount of depression of the pedal 24 from the start of sewing (when the cloth edge detection control setting switch 44 described later is off) or a speed corresponding to the setting of the dial 52 ( When the setting switch 44 is on, sewing is performed at high speed (hereinafter referred to as high speed).
This is a high speed/low speed start setting switch to select either one. 38 is a switch for setting the thread sweeping operation, 40 is a needle lift finger cold button switch that commands the upward movement of the presser foot and needle (top dead center stop) with one-bush action, 42
is a reverse stitch setting switch that specifies reverse stitching that repeats forward and backward for each stitch.

Inside the motor control box 22, there are a switch and a mode detection circuit that select one forward stitch or one backward stitch according to the depression mode of the pedal 24, a switch that detects the depression of the pedal 24, a potentiometer, a motor energizing circuit, and a mode detection circuit. When the cloth edge detection control setting switch 44, which has a built-in protection circuit and is installed for carrying out the present invention, is off, the dial and switches 32f described above are turned off.
, 32b, 34f, 34b, 36, 38, 40 and 4
2 and the depression operation of the pedal 24, various conventionally known sewing operations such as continuous stitching, single-stitch stitching, and basting are performed, and in the case of continuous stitching, the sewing speed corresponds to the amount of depression of the pedal noll 24. Further, a quick back switch 54 is provided at the tip of the arm 16, and while this is closed, a quick back solenoid is energized to perform back sewing. Hereinafter, parts related to the implementation of the present invention will be explained. On the front side of the sewing control box 26, there is a dial 43 for setting the number of sewing steps, considering sewing from one end of the cloth to the other end as one step, and a dial 43 for setting the number of sewing steps. The fabric is detected when the fabric edge detection control setting switches 44, 44 are closed and the pedal 24 is depressed, which specifies automatic sewing control that automatically performs sewing start control and sewing stop control by detecting the presence or absence of the fabric. Then, as will be described later, sewing is automatically started at a certain time T48 after the detection.
The dial 48 that sets the time T48, the dial 50 that sets the time T5O, and the dial 44 that set the time T5O, which automatically stops sewing at a low speed when the sensor detects that there is no cloth after the automatic sewing start, after a certain time T5O. A dial 52 is attached to set the sewing speed when closing.

46 is a light emitting diode that is lit when 44 is closed.

A reflective photo sensor 56 is mounted on the face plate 17 at the tip of the arm 16.
is attached, and a reflective surface 61 is attached to the throat plate 60 of the bed 12.
is formed.

Below, in order to explain these mutual relationships, a front view of the lower part of the tip of the arm 16 is shown in Fig. 2a, and a side view is shown in Fig. 2b.
2c, and the top view is shown in FIG. 2c, the reflective surface 61 is formed in front of the needle 66 when the operator is facing the sewing machine, and is
As clearly shown in the figure, the reflective photosensor unit 56 is arranged on the optical axis which is inclined with respect to the upper surface of the throat plate 60 and perpendicular to the inclined reflective surface 61, and is fixed to the face plate 17. As a result, the light emitting and light receiving axes of the photosensor unit 56 are inclined at an angle with respect to the axis of the needle 66, ie the vertical axis, as clearly seen in FIG. 2a. As a result, when the cloth 88 is above the reflective surface 61, even if the light from the sensor unit 56 is reflected by the cloth 88, one reason is that each reflection is diffused, and the other reason is that the light is not reflected on the cloth 88. Since the reflected light is projected obliquely and goes in a direction away from the reception window of the sensor unit 56, the amount of light received by the sensor unit 56 is small. On the other hand, when there is no cloth 88 on the reflective surface 61, the light projected from the unit 56 is strongly reflected by the reflective surface 61 and goes toward the receiving window of the unit 56, so the unit 56
The amount of light received at 6 is extremely large. As a result, in the sensor unit 56, it is easy to set the threshold level for distinguishing between cloth detection and non-detection, and the detection accuracy is high. In addition, in FIGS. 2a, 2b, and 2c, 62 is a sliding plate, 64 is a needle bar, 66 is a needle, 68 is a presser foot bar, 70 is a fabric presser foot, 72 is a thread remover, and 74 is a thread remover solenoid unit. , 76 is a quick back solenoid unit.

58 is a light emitting diode that lights up when the unit 56 detects cloth.

In the case where the upper fabric and lower fabric have approximately the same shape, and in the case where a small item such as pocket material is placed on top of a larger lower fabric as the upper fabric, in the former case, fabric detection will not work properly for both the upper fabric and the lower fabric. There is no problem with the control, but with the latter, if the edge of the upper fabric is not detected and sewing control is not performed, even if the sewing of the upper fabric (accessory) is finished, only the lower fabric will continue to be sewn. There's a problem. Therefore, in this embodiment, a fixing member 82 is attached to a connecting rod that connects the presser rod 68 and the presser foot 70 with a screw 84.
A reflective adapter is attached to this fixture 82 to allow the sensor 56 to detect only the upper cloth when the upper cloth is a small item such as pocket fabric. The top view with the adapter installed is shown in Figure 3a, and the front view is shown in Figure 3b.
The adjuster 84 of the adapter is shown in FIG.
The cross-sectional view of , that is, the cross-sectional view of
d, with the presser foot 70 and needle 66 placed above. A front view of the raised state is shown in Fig. 3e. In these drawings 88a
88b is the lower cloth, and 88b is the upper cloth. The adapter includes a roughly dogleg-shaped adapter arm 78, an adjuster 84, a guide plate 92, and a reflective arm 86. An adjuster 84 is fixed to one end of the adapter arm 78, and a guide plate 92 is coupled to the outer periphery of the adjuster 84 so as to be slidable in the vertical direction.A reflection arm 86 is fixed to this guide plate 92 with screws 96, 97. has been done. The reflective arm 86 has a pin screw 91 passing through the adjuster 84,
90 is fixed. Coil springs 94, 95 are inserted inside the adjuster 84, and these 94,
95 is trying to separate the reflective arm 86 from the adjuster 84. A reflective surface 87 is formed at the tip of the reflective arm 86 and is perpendicular to the optical axis of the sensor 56 . As shown in FIGS. 3a, 3b, 3c and 3d, the presser foot 7
0 is lowered, the reflection arm 86 hits the lower fabric, so the coil springs 94, 95 are compressed. However, when the presser foot 70 is raised as shown in FIG. , 95 are lowered downward, and the heads of the pin screws 91, 90 are in contact with the upper surface of the adjuster 84. As a result of such a spring action, for example, the presser foot 70 becomes 8? Where it rises, the reflex arm 86
rises only a small distance of about 27 WL. As shown in FIG. 3e, this means that even when the presser foot 70 is raised (for example, when setting the cloth before starting sewing),
This is to enable the upper cloth to be positioned on the reflective surface 87. The adapter arm 78 is fixed by a screw 80 to a fixture 82 fixed to the presser bar, and can be removed by loosening the screw 80. When the adapter arm 78 is attached, the reflective surface of the throat plate 60 is normally covered with the lower cloth 88a, and the sensor 56 detects the presence or absence of the cloth on the reflective surface 87 of the arm 86. Note that even if the lower cloth 88a is no longer on the 61, the optical path between the sensor 56 and the reflective surface 61 is blocked by the arm 86, and the reflective surface 87 faces the sensor 56, so the adapter arm 78 is attached to the fixture. 84, the sensor 56 always detects the presence or absence of cloth on the reflective surface 87. FIG. 4a shows the aforementioned switches and dials 43.
52, cloth detection/non-detection of the sensor 56, and various control operations in response to the depression operation of the pedal 24. The main elements of this system are the microcomputer MCP, which includes a central processing unit 146, ROM 148, RAM 150, input/output port (1/0) 152, and address counters 154, 15.
5. Clock pulse oscillator 156, address bus 158
, data bus 159, etc., and its I/01
The various switches, dials, etc. described above are connected to 52 directly or indirectly through a signal processing circuit, and furthermore, the I/
0152 is connected to control lines for the drivers of the thread wiper solenoid 74, presser foot lifting solenoid 100, and thread trimmer solenoid 110, and is also connected to a drive control unit 142 including a microcomputer that mainly performs conventional sewing control. The control of the solenoids 74, 100 and 110 is handled by the microcomputer MCP, and the control of the conventional dials and units 32f
The drive control unit 142 performs reading of the settings of 42 to 42, conventional sewing control in response to pegle depression, and control of the clutch/brake unit 18. Drive control of the motor M is performed by an electric circuit within the motor control box 22 in response to the operation of the switch buttons 28 and 30. In the clutch brake unit 18 (Fig. 4a), 120 is a flywheel, 122 is an electromagnetic clutch coil, 124 is a belt, 126 is a pulley 18, 128 is a brake shoe, 130 is an electromagnetic brake coil, 132 is a clutch shaft, and 134 is a movable clutch. The plate 136 is a movable brake plate, and the belt 124
is stretched around a pulley 20 connected to the upper shaft. The quick-back switch 54 is connected to the I/0152 so that the MCP detects its opening/closing, but the activation control of the quick-back solenoid 76 is performed by a driver connected to the switch 54. To explain the relationship with reference to FIG. 4b, quickback solenoid driver 98 is connected to signal voltage source Vcc via switch 54, and driver 98 energizes quickback solenoid 76 while 54 is closed. do. The solenoid 76 is of a rotating type, and its bias rotates the rotor, which shifts and drives the gear of the direction switching mechanism via the link, thereby switching the direction of rotation of the lower shaft relative to the upper shaft. When the solenoid 76 is not energized, the lower shaft is connected to the upper shaft in a forward cloth feeding relationship, and when the rotor of the solenoid 76 rotates by a predetermined angle or more, the lower shaft is connected to the upper shaft in a backward cloth feeding relationship. . Therefore, when the switch 54 is momentarily closed as in the case of the first narrow pulse shown in FIG. 4c, the solenoid 76 is deenergized before the rotor of the solenoid 76 rotates sufficiently. Even when it rotates, the lower shaft rotates in the forward cloth feeding direction, and the cloth feeding does not move backward. However, the switch 54 is turned on for a predetermined period of time. If the above is closed, the rotor of the solenoid 76 rotates sufficiently, and the lower shaft 108 is coupled to the upper shaft in a backward cloth feed relationship. When the upper shaft rotates, the lower shaft reverses, and the cloth feed is reversed. . In any case, cloth feeding is performed only while the upper shaft is rotating. The thread trimming solenoid is placed near the lower shaft under the bed, and when it is energized, the rotation of the lower shaft is transmitted to the thread cutting mechanism, which rotates the thread cutting teeth and cuts the thread. The microcomputer MCP (7) ROM 48 has the required control program data and constant data stored in a fixed memory in advance, and the ACP reads the input state of the I/0152,
Sewing control is performed based on the data in the ROM 48.

The operation flow of the sewing control related to the present invention is shown in FIGS. 5a and 5b, and the time chart 6.
Shown in Figure a, Figure 6), Figure 6), and Figure 6c. The operation of the MCP determined by the ROM data will be described below with reference to these drawings, and the outline thereof is as follows. Note that this is the case when the cloth edge detection control setting switch 44 is closed, and when the switch 44 is open, the sewing control is performed in response to a conventionally known pedal operation. (1) Automatic start...
...If the sensor 56 detects cloth while the pedal is being depressed, sewing will automatically start after the time set by the dial 48 from the cloth detection. Even if the pedal is depressed when the sensor 56 does not detect cloth, the machine will not start. vice versa,
If the pedal is depressed while the sensor 56 is detecting the fabric, sewing starts in response. (2) Automatic stop...
...When the sensor 56 no longer detects the cloth during sewing, the sewing machine automatically switches to a predetermined low speed sewing, and then automatically stops sewing after the time set with the dial 50. (3) Each time it stops automatically in (2), 1 is subtracted from the setting value of the dial 43, and when the remaining value becomes zero, the thread is automatically cut, the thread is swept away,
The presser foot 70 is driven upward.

If the residual is not zero, it automatically returns to (1). (4) Forward and backward one stitch... When the quick back switch 54 is closed with the pedal depressed, the upper shaft is driven for the stitch length (T2) after that, and this After driving, if the switch 54 is closed, it will be driven one more stitch, and this will continue thereafter.

As shown in FIG. 4c, when the on period of the quick back switch 54 is short, the operating amount of the quick back solenoid 76 is small, so the rotation of the upper shaft after t1 causes the lower shaft to feed the cloth forward, and the quick back switch 54 is turned on. If the period is long, the lower shaft feeds the fabric backwards, and sewing continues while the sewing machine 54 is closed. In other words, quick back switch 5
If 4 is momentarily closed, it will be one stitch forward stitch, and 54 will be T. O
If 54 is closed longer than t1+ and less than t1+, one stitch of backward sewing will be performed, and if 54 is closed longer than t1+T2, one stitch or more of backward sewing will be performed. t1 is the reversal switching waiting time that is longer than TCX), T
2 is a one-stitch driving period. (5) Setting the number of low-speed sewing steps... When the quick back switch 54 is turned on with the pedal released, the number of times it is turned on is accumulated and stored in memory, and when the pedal switch is turned on, the quick back switch 54 is turned on. It controls low-speed sewing until it turns off, and when it turns off, it stops and subtracts 1 from the memory value, and waits until the remaining value becomes zero (
Move on to 1).

While the remaining value is not zero, low-speed sewing starts as if the pedal is depressed, and stops each time the pedal is released. Cloth detection is not involved in these controls. In (1), if the switch 36 is set to slow start, the sewing speed is set for a predetermined time T from the start.

At a predetermined low speed for 1, turn the dial 5 after exceeding TO1.
The speed will change to the one set in step 2. When the switch 36 is set to slow start 0FF, the speed set by the dial 52 is achieved from the start. Next, the sewing control of the above-mentioned (1) to (5) will be explained with reference to FIGS. 5a and 5b.

First, the relationship between the address of RAM 15O and the data stored is as shown in Table 1 below. In Table 1, addresses 0 to 7 are direct registers that can be directly addressed, and addresses 32 to 63 are indirect registers that can be addressed by moving the address to a general-purpose register (address 0 or 1).

One byte consists of 8 bits.

When the power on switch 28 is turned on, the motor M is started, the sewing control box is turned on, and the power is connected to each part of the system shown in FIG. 4a.

When the microcomputer MCP is powered on, it initializes the I/0152 to the input waiting state, and stores the RAM 150
is set to the waiting data, and then reads the input of I/0152. Note that the input to the I/0152 is read each time there is a change in state depending on the input, or at regular intervals or at each step of the progress of the control program. When the cloth edge detection control setting switch 44 is open, the conventionally known sewing control is mainly executed by the microcomputer of the drive control unit, and the MCP is controlled by the solenoid driver 1 from the microcomputer of the drive control unit.
02, 112 and 114, and transmission of the quick-back switch 54 ON signal thereto. When the cloth edge detection control setting switch 44 is closed, the MCP gives a start command, a stop command, a low speed designation, high speed data, needle raising, etc. to the drive control unit 142, and causes the unit 142 to control the clutch/brake unit 18.

Now, when the switch 44 is turned on, the MCP first reads the number of sewing steps, which is the set value of the dial 43, and stores it in the register R3 (step 2).

Then, the number of sewing steps is stored in a register R4 used as a subtraction count. The number of sewing steps is the set number of steps when sewing is automatically started when cloth is detected and sewing is automatically stopped when cloth is not detected. Set to 4 when sewing the edge of a square cloth. Next, the MCP checks the output of the sensor 56, and if it is "cloth detected", it assumes that the cloth is set under the needle, and checks whether the pedal switch 25 is on (depressed) (step 4). If it is on, sewing starts after the time T48 set by the dial 48. This means that when the cloth is set under the needle with the pedal 24 depressed, the process will automatically start after T48 from the cloth detection. ζ8 is selected because the sensor 56 detects the cloth immediately after or during the cloth operation, so the operator waits until the cloth is sufficiently set under the needle, the operator does not have to worry about the danger, and the operator The intention is to give some extra time to the process, but in any case, this time is arbitrarily set by the operator using the dial 48, so the operator is aware of the time ζ8 from cloth detection to automatic start. If the pedal switch 25 is off when the sensor 56 detects the cloth, the sewing machine waits for the pedal switch 25 to turn on (step @) and immediately starts sewing. In this case, set the cloth and then press the pedal 24.
has been stepped on, and the sewing machine is fully prepared for sewing, so the delay time (T48) is not taken. Start sewing operation (
In step 6), if the switch 36 is in the slow dart ON state, the predetermined time T is reached. lT at low speed. After l, the speed is set on the dial 52, and if the slow start is 0FF, the speed is set on the dial 52 from the beginning. Further, if the quick back switch 54 is closed during the sewing operation, the fabric is fed backward during that time. During the sewing operation, the pedal switch 25 is monitored, and when it is turned off, sewing is stopped by stopping the needle down, and the sewing machine waits for the pedal switch 25 to be turned on. Sewing continues while the pedal switch 25 is on, and during that time the number of steps set on the dial 43 is compared with the contents of the register R3, and if they differ, it is assumed that the setting on the dial 43 has been changed and a dial is sent to the register R3, R. 43 settings are memorized. During this sewing, the reflective surface 61 or 87 is covered with the upper cloth as shown in FIG. 7a or 8a, and the sensor 5
6 detects cloth. Sewing progresses to figure 7b or 8.
As shown in figure b, the end of the upper cloth 88b is connected to the reflective surface 61 or 8.
7 and the sensor 56, the sensor 56
Give a "no cloth" signal to the MCP. Then, the MCP switches to low-speed sewing (step @), and after the time T5O set on the dial 50 has elapsed (step [phase]), the needle lowers and stops sewing. This completes one step of sewing. The situation is shown in FIG. 7c or 8c. In these drawings, the distance between the edge of the upper cloth 88b and the needle 66 is T.
It is determined by 4O. When the sensor 56 detects the absence of cloth for the first time (FIG. 7b or FIG. 8b), the distance between the edge of the upper cloth and the needle 66 is a constant value determined by the mounting position of the sensor 56. Time until final stop T5
O" is determined by the dial 50 as described above. This is because the amount of cloth feed changes depending on the fabric and the stitch setting dial 32f, etc., so the sewing stop position can be set and adjusted arbitrarily accordingly. This is because we intended to be able to adjust the distance between the edge of the fabric and the sewing stop position as desired.Now, when one sewing process is finished, the MCP is calculated based on the contents of register R4, that is, the remaining value of the sewing process up to the previous time. Subtract 1, move it to the accumulator register, check whether the subtracted value is zero,
If it is not zero, it is determined that the set number of sewing processes have not yet been completed, and the process returns to step 8 in the flowchart of FIG. 5a, returning to the automatic start standby conditioned on cloth detection.

In the case of a four-cornered cloth, the operator will have 90
Since the zero cloth is turned, the sensor 56 detects the cloth.

Even if it is not a square cloth, the process up to the edge of the cloth is one process, so if the setting process is completed and the setting process remains, the cloth is turned and the sensor 56 detects the cloth.

The sewing control in the next step is also as described above. When one process is completed and the setting process is completed, the presser foot 70 is lowered once (step 9; this de-energizes the solenoid 100).
The needle is stopped at the upper position, the solenoid 110 is energized to cut the thread (step @), the solenoid 74 is energized and the thread wiper 72 is rotated (step ◎), and the thread between the needle and the presser foot 70 is cut. to the side, energizes the solenoid 100, and presses the presser foot 7.
Increase 0 (step @). The above-mentioned thread trimming @, thread sweeping @, and presser foot 70 raising O are the sewing end operations, and sewing is defined as at least when the cloth presser foot 70 is raised @. With this sewing end operation, the number of sewing steps set with the dial 43 is completed. FIG. 6a shows the operation timing of each part in sewing the set number of dials 43 as described above. In addition, FIG. 6a shows the setting number of the dial 43 is 4 and the slow start switch 36 is 0N. It is something. When the switch 36 is ON, the speed set on the dial 52 is maintained even during TOI (this is called high speed). After starting the sewing operation (step 6), the pedal switch 25 is turned off (step 7), the needle is stopped lowering (step 8), and then the pedal switch 25 is turned on (step 9). FIG. 6b shows the timing when the pedal is temporarily released and then depressed again after the start of sewing.
During this interruption (from 7 to @ in Fig. 6b), the sensor 56 continues to detect the presence of cloth, so the MCP does not regard it as the end of one process. Next, the control operation in response to the closing operation of the quick-back switch 54 will be explained with reference to FIG. 5a. It is preferable to assume a state in which the sensor 56 does not detect cloth (FIG. 7c or 8c).

), the switch 54 is closed (step @), and the pedal switch 25 is further turned on (step @), the MCP
reads t1 of the ROM data, drives the upper shaft after t1, drives the upper shaft during T2 of the ROM data, then stops the upper shaft, and returns to cloth detection 3. In other words, if the switch 54 is closed while the pedal switch 25 is on due to non-detection of cloth, the MCP will then drive the upper shaft for one stitch sewing time T2 after t1 when t1>TOO, regardless of the closing time length. As described above, if the closing of the switch 54 is less than T.O, the rotor of the solenoid 76 is deenergized before it rotates sufficiently, so the direction switching mechanism 104 ( Figure 4b) maintains the lower shaft connected to the upper shaft in the forward cloth feed direction, so that the lower shaft rotates forward only for one stitch as shown in Figure 4c, and the cloth moves forward. The switch is driven and one stitch is sewn forward.On the other hand, the switch 54 is energized.
The rotor of the solenoid 76 rotates sufficiently to cause the direction switching mechanism 104 to switch and connect the lower shaft to the upper shaft in the backward cloth feeding direction, so when the MCP rotates the upper shaft a little after t1, the cloth will not move. It will be fed back by one stitch. Then, after T2, the MCP traces back to O-3-@, and at step @, the switch 54 is on, and the pedal switch 25 is on, that is, when the cloth is not detected, the pedal switch 25 is turned on.
is on and the switch 54 is closed for at least t1+T2, sewing of the next stitch is started. To summarize, if the switch 54 is closed when the pedal switch 25 is on due to non-detection of cloth, if the closing time is less than TCX), one forward stitch will be sewn, and the sewing time will be greater than or equal to t(X) and less than or equal to t1+. When t1+T2 is exceeded, it becomes a single backward stitch, and when t1+T2 is exceeded, it becomes a backward stitch of two or more stitches, and the switch 54 is opened even when the backward stitch is two or more stitches, or the sensor 56 detects the cloth, or the pedal switch 25 is turned off. When this occurs, continuous backward sewing will stop. Next, the storage of the set number of low-speed sewing processes and the control of the number of low-speed sewing processes based on the storage of the set number of low-speed sewing processes following step [Yes] will be explained.

The sensor 56 does not detect cloth (step 3), and the quick back switch 54 is turned on (step @).
Furthermore, if the pedal switch 25 is off at that time (step 3), the number of times the switch 54 is turned on is accumulated and stored in the accumulator register (step 9), and the register R,
The accumulated value is stored in memory. This process is repeated every time the quick back switch 54 is turned on, and when the pedal switch 25 is turned on (step [Yes]), low-speed sewing starts as if the operator has commanded sewing. When the switch 25 is turned off, it stops (step 9), considers this to be the end of one low-speed sewing process, subtracts 1 from the contents of register R7, checks the remaining value, and if it is zero, stores it in advance in register R7. Cloth detection automatic start C
When the value is not zero, the remaining value is updated and stored in the register R7 (step [phase]), and the next low-speed sewing process is started after the pedal switch 25 is turned on. When the low-speed sewing process is started, the set number of low-speed sewing processes (memory in the register R7) are performed until the process starts and the number stored in the register R7 is used even if the sensor 56 detects cloth in the middle. To explain the significance of setting and controlling this low-speed stitching, for example, when forming a stitch as shown by a triangle in the lower left corner of the upper cloth 88b in FIG. 8a, the oblique side 1
62 and the other side 163, the sensor 56 does not detect the cloth, and it is preferable to hold the cloth by hand and perform low-speed sewing in these small areas. In this case, set the number of low-speed sewing steps to 2 with the switch 54, and turn the dial 43.
By setting to 4, first 162 and 163
The setting number of low-speed stitches is used up at the sewing point 163, and from the next point 164, the cloth detection starts automatically, and the high-speed sewing process starts, and one high-speed sewing process is performed at points 165, 166, 167, and 168, respectively. Finished, point 168
The high-speed sewing of the number set with the dial 43 is finished. Therefore, by closing the switch 54 twice and setting the low speed step to 2, the stitches corresponding to 162 and 163 can be sewn symmetrically from point 168 at low speed. adapter 7
Even when 8-86 and 87 are not installed, when forming a seam in a curved shape such as an arc, press switch 5 as described above.
By setting low-speed sewing in step 4, the set number of low-speed sewing can be automatically performed even if the sensor 56 does not detect the cloth at the start of sewing or during sewing. Therefore, by setting the number of low-speed sewing processes using the quick-back switch 54 and the number of high-speed sewing processes using the dial 43 in advance in correspondence with the cloth shape and the shape of the seams to be formed therein, low-speed sewing control can be achieved. High-speed sewing control is automatically switched and selected at a predetermined point, simplifying the operator's work and improving sewing work efficiency. The setting of the number of low-speed sewing processes and the operation timing of each part in the low-speed sewing control explained above are explained in 6c.
As shown in the figure.

The circled numbers in the diagram indicate each step of the flow shown in Figure 5a. In the above embodiment, when the low-speed sewing process is started, the low-speed sewing is continued until the number of processes stored in the register R7 is completed. When each indicates cloth detection, a predetermined period of time (for example, 25 seconds)
The register R7 may be cleared on the condition that the cloth detection is not interrupted, and the process returns to step 3 or 4 to automatically start high-speed sewing.

Further, a key for clearing the register R7 may be provided, and when the pedal 24 is depressed later, the register R7 may be cleared. Further, in the embodiment described above, the reflective surface 61 is a surface cut diagonally into the throat plate 60, but the reflective surface may be formed of another metal plate or a mirror, or the reflective surface may be made to protrude from the throat plate 60.

An example thereof is shown in FIG. 9a (top view) and FIG. 9b (side view). In these drawings, reference numeral 160 denotes a reflective member, and an inclined surface 161 on the upper surface thereof serves as a reflective surface, and the member 160 is fixed to the needle plate 60. Although specific embodiments have been shown above, the present invention can be implemented by making various modifications and changes that are easy for those skilled in the art within the scope of the claims that are not specified in the embodiments. .

[Brief explanation of the drawing]

1a is a perspective view showing an outline of the appearance of a sewing machine embodying the present invention, FIG. 1b is an enlarged front view showing the front of the sewing control box 26, and FIG. 2a is an enlarged view showing the lower part of the tip of the arm 16. A front view, FIG. 2b is an enlarged side view, and FIG. 2c is a plan view of the main part. Figure 3a is a plan view of the main part in the state where the adapter for detecting small articles and clothing is attached, Figure 3b is an enlarged front view with the adapter attached, Figure 3c is an enlarged side view with the adapter attached, and Figure 3d is the enlarged side view with the adapter attached.
The figure is a sectional view taken along the line ■D--■D in FIG. 3b, and FIG. 3e is an enlarged front view showing a state in which the presser foot 70 is raised with the adapter attached. Fig. 4a is a block diagram showing the coupling relationship of each element of the electrical system that is installed in the sewing machine shown in Fig. 1a, especially for controlling sewing, and Fig. 4b is a block diagram showing the connection relationship of each element of the electrical system that is installed in the sewing machine shown in Fig. 1a. FIG. 4c, a block diagram showing the coupling relationship, is a time cheat showing the correlation between the on time of the quick back switch 54 and the rotational direction of the lower shaft. 5a and 5b are flowcharts showing the main control operations performed by the microcomputer MCP shown in FIG. 4a, and FIGS. 6a, 6b, and 6c.
The figure is a time chart showing the operation timing of each electric element in response to the control of the MCP. Figure 7a is a plan view of the main part during the sewing operation when the sensor 56 is detecting the cloth, with no adapter attached, and Figure 7b is the main part during the sewing operation when the sensor 56 no longer detects the cloth. The plan view, FIG. 7c, is a plan view of the main part when sewing is stopped. Fig. 8a is a plan view of the main part during sewing operation when the sensor 56 is detecting the cloth with the adapter attached, and Fig. 8b is a plan view of the main part during the sewing operation when the sensor 56 no longer detects the cloth. The plan view, FIG. 8c, is a plan view of the main part when sewing is stopped. FIG. 9a is a plan view showing deformation of the reflecting surface, and FIG. 9b is a side view. FIG. 10 is a block diagram showing block divisions corresponding to sentence divisions of claims. 10: Sewing machine table, 12: Sewing machine bed, 14: Standard, 16
: Arm, M: Motor, 17: Face plate, 18: Clutch and brake, 20: Pulley, 22: Motor control box, 24: Pedal, 25: Pedal switch, 26: Sewing control box, 28: Power on switch button, 30 : Power off switch button, 32f: Forward 1 stitch length setting dial, 32b: Backward 1 stitch length setting dial, 34f: Sewing start single-double setting switch, 34
b: Sewing end single-double setting switch, 36: High-speed/low-speed start setting switch, 38: Thread wipe setting switch, 40: Needle raise command button switch, 42: Backstitch setting switch, 43: Sewing man-hour setting dial, 44 : Fabric edge detection control setting switch, 46: Light emitting diode, 48: Sewing start timer dial, 50: Next process start timer dial, 52: High speed sewing speed setting dial, 5
4: Quick back switch, 56: Reflective photo sensor, 58: Light emitting diode, 60: Throat plate, 61: Reflective surface,
62: Slip plate, 64: Needle bar, 66: Needle, 68: Presser bar, 7
0: Presser foot, 72: Thread wiper, 74: Thread wiper solenoid,
76: Quick back solenoid, 78: Adapter arm, 80: Mounting screw, 82: Fixture, 84: Adjuster, 86: Reflective arm, 87: Reflective surface, 88: Cloth, 88
a: Lower cloth, 88b: Upper cloth, 90, 91: Pin screw, 92
: Guide plate, 94, 95: Coil spring, 96, 9
7: Screw, 98: Quick-button solenoid driver,
100: Presser foot lifting solenoid, 102: Presser foot lifting solenoid driver, 104: Direction switching mechanism, 106:
Upper shaft, 108: Lower shaft, 110: Thread trimming solenoid, 11
2: thread trimming solenoid driver, 114: thread trimming solenoid driver, 116: feed dog mechanism, 118: thread trimming mechanism, 120: fly hole, 122: electromagnetic clutch coil, 124: belt, 126: pulley, 128: brake shoe, 130: Electromagnetic brake coil, 132: Clutch shaft,
134: Clutch movable plate, 136: Brake movable plate, 1
38: Electromagnetic brake driver, 140: Electromagnetic clutch driver, 142: Drive control unit, 144: Top dead center,
Bottom dead center sensor, MCP: Microcomputer, 146
:Central processing unit, 148:Read-only memory (R
OM), 150: Read/write memory (RAM), 152:
Input/output port (1/0), 154, 155: address counter, 156: clock pulse oscillator, 158: address bus, 159: data bus, 160: reflective member,
161: Reflective surface, 162, 163, 164: Seam, 1
65-168: points.

Claims (1)

[Scope of Claims] 1. In a sewing machine equipped with a foot pedal and an electronic control device that controls the sewing force of the sewing mechanism according to the pedal's depression: A cloth installed at the tip of the sewing machine arm that provides cloth detection information to the electronic control device. A detection means; and a time setting means that can be set manually; means; and a second control means for starting sewing bias of the sewing mechanism after a time set by the time setting means in response to a change in cloth detection information from no cloth to cloth present after the pedal is depressed;
A cloth detection sewing control sewing machine comprising: