JPH0295399A - Cloth end detection controller for sewing machine - Google Patents

Abstract

PURPOSE:To prevent an automatic operation control of a sewing machine from being stopped due to the number of pieces of cloth by reading and storing the transmission quantity of each of plural pieces of cloth interposed between a light emitting element and a light receiving element, and also, setting a cloth end detection threshold by a difference of the transmission quantity of every sewing section which is stored. CONSTITUTION:A cloth end detection threshold VTH2 is obtained by the transmission quantity Vb of a detection light which transmits through lines cloth B sewed to the lower cloth C obtained by executing a sensitivity read routine of a first detecting means, and the transmission quantity Va of a detecting light which transmits through the lower cloth C and the lined cloth B and the upper cloth A obtained by executing a sensitivity read routine of a second detecting means. It is stored as the cloth end detection threshold VTH2 in a memory which is brought to address designation. Thereafter, in each STEP, a relation to the cloth end detection threshold VTHn is set to the memory which is brought to address designation, and when this setting is completed, a sewing routine is called.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a fabric edge detection control device for a sewing machine that detects overlapping fabrics to be sewn, and in particular detects the presence or absence of work fabric or changes in its thickness using detection light. The present invention relates to a fabric edge detection control device for a sewing machine that detects.

[Prior Art] Conventional technology of a material edge detection control device for this type of sewing machine is disclosed in Japanese Patent Application Laid-Open No. 179494/1983 and Japanese Patent Application Laid-Open No. 1983-17949.
The technique disclosed in Japanese Patent No. 85386 can be mentioned.

The technology described in the former section sets the cloth edge detection sensitivity based on the difference in the amount of transmitted detection light projected from the light emitting element that is received by the light receiving element of the lower cloth and the overlapping lower cloth and upper cloth. be.

In addition, the technology described in the latter includes a detection means that includes a light emitting element and a light receiving element and detects the presence or absence or change in thickness of an object to be detected introduced between the two based on the amount of light transmitted. a variable attenuator for attenuating the output voltage from the reference voltage changing means; the output voltage of the reference voltage changing means is compared with the output voltage of the variable attenuator, and the output voltage of the detected object is determined based on the comparison result. a comparator that generates a detection signal; reference voltage setting means for adjusting the sensitivity and setting the output voltage of the reference voltage changing means to a predetermined level; and an output voltage attenuated by the variable attenuator. is the group i1! a first changing means for stepwise changing the attenuation layer of the variable attenuator until the output voltage set by the voltage voltage means is exceeded; and by the variable attenuator based on actuation of the first changing means. A determination means for determining whether the attenuated output voltage exceeds the output voltage set by the reference voltage setting means, a determination violation by the determination means, an output voltage attenuated by the variable attenuator, and the reference. The attenuation amount of the variable attenuator or t1 is adjusted so that the output voltage from the voltage changing means is at a level suitable for detecting the presence or absence of the object to be detected or the thickness thereof.
! and second changing means for changing at least one of the changing amounts of the voltage changing means.

[Problems to be Solved by the Invention] However, in the fabric edge detection control device of the sewing machine, for example,
When sewing pieces of fabric such as pockets, this is fine when sewing two pieces of fabric, the bottom fabric and the top fabric, together, but if there is a place where the bottom fabric itself is sewn together, the two pieces of fabric, the bottom fabric and the top fabric, will be sewn together at that point. Therefore, the automatic operation control of the sewing machine becomes impossible with the threshold value for detecting the cloth edge of the two pieces of cloth, the lower cloth and the upper cloth, which are sewn together.

Therefore, the present invention sequentially reads the amount of permeation of the overlapped lower fabric and upper fabric in accordance with the sewing order for each sewing section, so as to avoid the influence of the number of overlapped fabrics in the sewing section. An object of the present invention is to provide a fabric edge detection control device for a sewing machine that does not have a fabric edge detection control device.

[Means for Solving the Problems] A fabric edge detection control device for a sewing machine according to the first invention detects a plurality of fabrics to be sewn together, which are interposed between a light emitting element and a light receiving element constituting a plurality of detection means. and a reading instruction means for instructing to read the amount of transmission of each of the plurality of cloths combined, and the reading instruction means reads the amount of transmission of each of the cloths interposed between the light emitting element and the light receiving element. Sequentially performing each of the detection means according to the sewing order for each section,
A device comprising a reading storage means for storing the read transmission amount in a storage means, and a threshold setting means for setting a cloth edge detection threshold based on the transmission amount for each @ sewing section stored according to the continuous sewing order stored in the storage means. I'll go.

A fabric edge detection control device for a sewing machine according to a second invention includes a light emitting element and a light receiving element for detecting light projected from the light emitting element, and detecting means for detecting the amount of light transmitted through the fabric to be sewn. a reading instructing means for instructing to read the amount of light transmitted through the cloth to be sewn; and a reading instructing means that operates in accordance with the instructions of the reading instructing means to read the amount of light transmitted through the cloth to be sewn detected by the detecting means. storage means for storing a plurality of threshold values set by a threshold value setting means for setting a threshold value for detecting the presence or absence of cloth based on the amount of cloth according to a sewing order; Compare the amount of transmission of
The cloth edge determination means determines whether the target cloth is "present" or "absent", and when the determination result of the cloth determination means changes from "presence" to "absence", the cloth edge determination means determines that it is a cloth edge. is.

[Operation] In the first invention, the amount of transmission of each of a plurality of fabrics to be sewn together and a plurality of fabrics in combination interposed between a light emitting element and a light receiving element constituting a plurality of detection means is read. The reading instruction means reads the transmission amount of each of the cloths interposed between the light emitting element and the light receiving element, and the reading storage means sequentially reads the transmission amount of each of the cloths interposed between the light emitting element and the light receiving element for each of the detection means in accordance with the sewing order for each sewing section, and The read amount of transmission is stored in the storage means. Then, the threshold value setting means sets the cloth edge detection threshold value based on the difference between the amount of penetration for each sewing section stored in accordance with the continuous sewing order stored in the storage means. Therefore, if you select the cloth edge detection threshold value for each sewing section, the cloth edge of that sewing section can be detected for each sewing section, and the automatic operation control of the sewing machine will stop depending on the number of overlapped sheets of cloth. There's nothing to do.

In addition, in the fabric edge detection control device for a sewing machine according to the second invention, light emitted from the fabric to be sewn is detected by a light emitting element constituting the detection means and a light receiving element that detects the light emitted from the light emitting element. Detect the amount of permeation. Then, the reading instruction means is instructed to read the amount of light transmitted through the cloth to be sewn, and the detection means detects () according to the instruction from the reading instruction means.
Based on the amount of light transmitted through the cloth to be sewn together, the threshold value setting means sets a threshold value for detecting whether the target cloth is "present" or "absent" and is stored in the storage means according to the sewing order.

When the sewing machine is operating, the threshold value set by the threshold value setting means is compared with the amount of light transmitted by the detection means to determine whether the target cloth is "present" or "absent". Then, when the determination result of the cloth determining means changes from "present" to "absent", it can be determined that there is a cloth edge.

[Example] Examples of the present invention will now be described.

FIG. 1 is a block diagram showing the electrical configuration of a material edge detection control device for a sewing machine according to an embodiment of the present invention.

Further, FIG. 2 is a front view of essential parts showing a detection means of a material edge detection control device of a sewing machine according to an embodiment of the present invention, and FIG.
FIG. 3 is a side view of a main part of the detection means shown in the figure. And the fourth
The figure is an explanatory diagram showing a plane positional relationship between a detection means of a fabric edge detection control device of a sewing machine according to an embodiment of the present invention and a plurality of pieces of fabric;
FIG. 5(a) is a front view of main parts showing a panel of a material edge detection control device of a sewing machine according to an embodiment of the present invention, and FIG. FIG. 3 is a circuit configuration diagram of a panel of the control device.

2 to 4, a light emitting element 5 is attached to a face plate 1 fixed to a sewing machine main body (not shown) via a support member 2.
, 6 is fixed to the face plate 1. This light emitter 3 is provided with two light emitting elements 5 and 6 that project detection light onto a needle plate 4 fixed to a table (not shown). Furthermore, light receiving elements 7 and 8 are arranged on the needle plate 4 in pairs with the light emitting elements 5 and 6 to receive detection light from the light emitting elements 5 and 6.

The light-emitting elements 5 and 6 and the light-receiving elements 7 and 8 which are paired with the light-emitting elements 5 and 6 and receive detection light from the light-emitting elements 5 and 6 are the light-emitting element 5 and the light-receiving element 7, and the light-emitting element 6 and the light-receiving element. 8 constitute a first detection means 9a and a second detection means 9b, respectively.

As shown in FIG. 4, between the light-emitting elements 5, 6 and the light-receiving elements 7.8, a lower cloth C and an upper cloth A overlapped with a matching cloth B sewn with the lower cloth C are connected to the throat plate. It is placed on top of 4.

As a result, between the light emitting elements 5, 6 and the light receiving elements 7, 8,
The positional relationship is such that the lower fabric C and the upper fabric A, which overlaps the lower fabric C and the combined fabric B sewn together, are interposed, and by the detection light,
It is possible to detect the presence or absence of the lower cloth C and the upper cloth A overlapping the lower cloth C and the seam 15B sewn together, or the difference in the amount of transmission thereof.

As shown in FIGS. 1 and 5, light emitting elements 5.6 are connected to the boats P4 to P5 of the microcomputer 10 via light amount adjustment means. The light amount adjusting means includes a control voltage generation circuit 11 and a current setting circuit 12.
, an LED drive circuit 13 and a pulse generation circuit 14. The control voltage generating circuit 11 changes its output voltage in response to 2-bit digital outputs from ports P4 to P5 of the microcomputer 10. Further, the current setting circuit 12 sets the value of the current flowing through the light emitting elements 5 and 6, that is, the brightness of the emitted detection light, in accordance with the output of the control voltage generating circuit 11. Further, the LED drive circuit 13 is made up of an analog gate, etc., and is opened and closed by the pulse generation circuit 14, and the output of the current setting circuit 12 is applied to the light emitting elements 5 and 6.

A pulse generation circuit 14 that controls opening and closing of the LED drive circuit 13 controls a signal detection circuit 15 in synchronization with the opening and closing control of the LED drive circuit 13. The light receiving element 7.8 is connected to the input side of the signal detection circuit 15, and the output side of the signal detection circuit 15 is connected to the input of a differential amplifier circuit 16.

Further, a differential amplifier circuit 16 is connected to the ports P6 to P8 of the microcomputer 10 via a comparison voltage generation circuit 17, and the comparison voltage generation circuit 17 is controlled by the 3-bit digital signals from the ports P6 to P8. Output VR
changes. The differential amplifier circuit 16 outputs the difference between the output vS from the signal detection circuit 15 and the output VR from the comparison voltage generation circuit 17 as an output vO to the boat P9. In other words, the output is determined by the sum of the "brightness of the detected light" detected by the light receiving element 7.8 and the "external brightness".
The difference between S and the output VR from the comparison voltage generation circuit 17 determined by the outputs of boats P6 to P8 as "external brightness", that is, the "brightness of the detected light" is determined by the analog input terminal. Output to P9.

Then, the changeover switch circuit 22 receives the output from the boat P3.
Activate. The changeover switch circuit 22 selectively operates only one of the first detection means 9a having a pair of light emitting element 5 and light receiving element 7, and the second detecting means 9b having a pair of light emitting element 6 and light receiving element 8. let That is, when the output of the boat P3 of the microcomputer 10 is "O", the first detecting means 9a of the pair of the light emitting element 5 and the light receiving element 7 has an output of 1 (when the output of the boat P3 of the microcomputer 10 is 1u, the light emission is Second detection means 9 for a pair of element 6 and light receiving element 8
b. In addition, the boat P10 of the microcomputer 10 has a RAM 21 used as an expansion memory.
is connected.

Furthermore, in the boat P12 of the microcomputer 10,
A step motor drive circuit 32 is connected and drives a step motor 33 that determines the stitches. Also,
A feed amount detector 31 is connected to the boat pH of the microcomputer 10. This feed amount detector 31 is for detecting the actual feed of cloth. These step motor drive circuit 32, step motor 33,
The feed amount detector 31 determines the size of the seam of the cloth.

In addition, in the boat P13 of the microcomputer 10,
An upper shaft motor drive circuit 35 is connected and drives an upper shaft motor 36 that determines the cloth feeding speed. Further, an upper shaft position detector 34 is connected to the boat P14 of the microcomputer 10. This upper shaft position detector 34 detects the position of the needle when stopping the feeding of the cloth. These upper shaft motor drive circuit 35, upper shaft motor 36, and upper shaft position detector 34 determine the needle position when stopping the cloth feed.

A switch 37 is connected to the boat P15 of the microcomputer 10 to the foot 1 for driving the step motor 33 and the upper shaft motor 36.

Furthermore, ports P1 to P of the microcomputer 10
2, the operation panel 18 is connected via the interface 18a.
It is connected to various switches and light emitting diodes used for display.

Specifically, one sensitivity setting switch and a display LED 20 are arranged on the operation panel 18, and each of the cloths interposed between the light emitting element 5.6 and the light receiving elements 7, 8 A display LE that displays the completion of sensitivity setting or a sensitivity setting error based on the processing result performed by the microcomputer 10 in response to the output from the sensitivity setting switch 19, which is the reading instruction means of this embodiment that instructs reading of the amount of transmission.
D20 lights up or flashes. The operation panel 1B includes, in addition to a sensitivity setting switch 19 and a display LED 20 that indicates completion of sensitivity setting or a sensitivity setting error.
An up switch 23 and a down switch that sequentially specify the memory M E (STEPn) that stores the cloth edge detection threshold THn (the above n is an integer such as 1.2, etc., and corresponds to the number of memories). 24, Memory M E (STE
An end switch 25 for inputting a code indicating that the storage of the cloth edge detection threshold VTHn has ended in Pn), and a memory M
The input mode switch 26 starts storing the cloth edge detection threshold value V THn in the memory M E (STEPn), and the memory M E (STEPn)
The sewing machine has a sewing mode switch 27 that starts sewing 5i using the cloth edge detection threshold value VTHn stored in TEPn). Note that a description of switches that are not directly related to the fabric edge detection control device of the sewing machine according to the other embodiments of the present invention will be omitted.

Next, as shown in FIG. 6(b), the operation of the fabric edge detection control device of the sewing machine of this embodiment configured as described above will be explained. B and below *C
An example in which the upper fabric A is sewn onto the lining 15B will be explained. The locations where upper cloth A will be sewn are in the order of "A", "I", "Tsu", and "Work" in Fig. 6(a).

Figure 7 shows a lower fabric C, a laminated fabric B sewn with the lower fabric C, and an upper fabric A@
FIG. 8 is an explanatory diagram showing the order of stitching, and FIG. 8 shows a memory M E (STE
FIG. 4 is an overall explanatory diagram of the cloth edge detection threshold value VTHn stored in Pn). 9 to 14 are flowcharts of a fabric edge detection control device for a sewing machine according to an embodiment of the present invention.

First, the detection means of the fabric edge detection control device of the sewing machine of this embodiment shown in FIG. As shown in the explanatory diagram showing the positional relationship when sewing upper cloth A to cloth B, first,
), a lower cloth C is interposed between the light emitting element 5 and the light receiving element 7 constituting the first detection means 9a, and the second detection means 9
The lower cloth C and the upper cloth A are interposed between the light-emitting element 6 and the light-receiving element 8 constituting part b.

FIG. 9 is a flowchart of the "sensitivity setting and sewing routine" of this embodiment. This routine is called at the beginning of the main routine in which the driving conditions of the step motor 33, which determines stitches (not shown), and the driving condition of the upper shaft motor 36, which determines the sewing speed, are set, and sewing control is performed according to these conditions.

In step S1, it is determined whether the input mode switch 26 is on, and when the input mode switch 26 is turned on, step S2
It is determined whether the input mode switch 26 is turned on immediately after the input mode switch 26 is turned on, and if the input mode switch 26 is turned on immediately after the input mode switch 26 is turned on, the memory ME (STEPn) that stores the cloth edge detection threshold value V THn is sequentially specified in step S3. 5TE
Set P to "1". If it is not immediately after the input mode switch 26 is turned on, the process enters step $4 without changing the 5TEP specified for ME (STEPn) in order to maintain the 5TEP currently being changed. Then, in step S4, [rS
TEP change routine" is called. Next, step S
5, it is determined whether the sensitivity setting switch 19 is on, and when the sensitivity setting switch 19 is on, the "first detection means sensitivity reading routine" is called at step S6A, and the "second detection means sensitivity reading routine" is called at step S86B. , Furthermore, in step 36G, the "sensitivity setting routine J" is called, and in step S7, the cloth edge detection threshold value VTH obtained in the "sensitivity setting routine" is called.
n is stored in the memory ME (STEPn). Thereafter, as long as the input mode switch 26 remains on in step S1, the routine from step S1 to step S7 is performed.

When the input mode switch 26 is off in step S1,
In step S8, it is determined whether the sewing start switch 27 is on, and when the sewing start switch 27 is off, the routine of step S1 and step S8 is repeatedly executed and stopped there.

In step S8, [When the start switch 27 is on,
In step S9, a "sewing routine" is called.

Next, the 1rs shown in FIG. 10 called in step S4
"TEP change routine" will be explained.

In step 311, it is determined whether the up switch 23 is on, and if the up switch 23 is off, step S'
At step 12, it is determined whether the down switch 24 is on. 15 in step 313 when the down switch 24 is on.
A memory M E (STE
5TEP that addresses Pn) is decremented by "1", and in step 814 it is determined whether 5TEP is less than "1", that is, it is less than 5TEP1, and 5TEP
If less than 5, address 5 in step 315.
Let TEP be 1 "9", that is, 5TEP9. This means that in this embodiment, the memory M E (STEPn) that stores the cloth edge detection threshold value VTtfn is 5TEPI to 5TEPI.
It means that it has 9 pieces of P9.

Further, when the up switch 23 is turned on in step S11, the memory M I:= (STEPn
) is incremented by U1J, and in step 319 the 5TEP addressing is r
Although it is 9J or more, it is determined. That is, it is determined whether it is 5TEP9 or more. 5TEP9J in step S19,
7 Uenotoki, 5TE addressing in step 520
Let P be "1", that is, 5 TEPI.

Then, when the predetermined number of 5TEPs is selected, when the end switch 258 is turned on in step S16, a setting is made in the memory FIN indicating the end of the number of 5TEPs selected at that time in step 317.

As mentioned above, in this routine, the cloth edge detection threshold VTH
The designation of 5TEP to address the memory M E (STEPn) that stores n, and the cloth edge detection threshold vTHn
The end number of 5 TEPs is set in the memory FIN which determines the end of M E (STEPn) for storing. As shown in Fig. 6(b), a lower cloth C, a combined mB sewn with the lower cloth C, and a lower cloth C and a combined cloth B
Applicable to the case where upper fabric A is sewn on. The places to sew the upper fabric A are shown in Figure 6 (a), “A”, “I”, “
It is assumed that the address is specified using 5 TEP numbers in the order of "1" and "work", and the cloth edge detection threshold value yr+in is stored in the memory ME (STEPn).

Here, the memory ME (S
The cloth asthma detection threshold @V THn stored in TEPn) is set as follows.

The detecting means of the fabric edge detection control device of the sewing machine of this embodiment shown in FIG. As shown in the explanatory diagram showing the positional relationship when sewing, first,
As shown in FIG.
@A lower cloth C and an upper mA are interposed between the light emitting element 6 and the light receiving element 8.

Then, when the "first detection means sensitivity reading routine" is called in step S6A, in step s21 the port P3
is set to "'O", and the changeover switch circuit 22 selects the first detection means 9a. In step 322, the 5-bit counter FSEL, which sets the signals input to the ports P4 to P8 of the microcomputer 10, sets the first signal, that is, all ports are set to "O", rooooOJ, and the register MADR registers the first detection means. The first address of the memory that stores the sensitivity obtained is set to V[^DRI. Step 523r The counter FSEL(7) value is set in ports P4 to P8. In step 324, the differential amplifier circuit 16
The sensitivity of the first detection means 9a (transmission of the detection light VO corresponding to the value of the counter FSEL) corresponding to the signals of the ports P4 to P8 outputted to the port P9 by and its output is input to the memory MA.In step 325, the counter FS
The sensitivity VO of the first detection means 9a of the memory MA corresponding to the value of EL is stored at address VLADRI of the register MADR. At step 326, counter FSEL is set to "11".
111" and the counter FSEL is "111".
11'', the next value is set in the flag VSEL in step 327, and the address V is set in the register MADR.
The next address V LADR2 following LADRI is set,
Return to step 323.

By repeating this operation, the counter FSE
The sensitivity VO of the first detection means 9a corresponding to the value of L is the address 1 to 32 of each register M ADR V LADRI~
When the counter FSEL becomes rllllllJ, this routine is exited. Note that the first detection means 9 corresponding to the value of the counter FSEL
The sensitivity VO (Vd) of a is all stored in the RAM 21.

When the execution of the "first detection means sensitivity reading routine" is completed, the "second detection means sensitivity reading routine" is called next.

First, in step 331, "O" of the port P3 of the microcomputer 10 is switched to "1", and the changeover switch circuit 22 selects the second detection means 9b. As a result, the lower cloth C and the upper cloth A shown in FIG.
Start measuring the amount of permeation. Boat P4 ~ in step 332
5-bit counter F that sets the signal input to P8
SEL sets the first signal, i.e. rooooOJ,
A register MADR is set to the first address VHADR of the memory storing the sensitivity obtained by the second detection means.

At step 333, the counter FSE is applied to ports 1 to P4 to P8.
The value of L is set. Boats P4 to P outputted to boat P9 by the differential amplifier circuit 16 in step 334
8, i.e. the second signal corresponding to the value of the counter FSEL.
The transmitted IVO of the light detected by the detection means 9b is determined, and its output is input to the memory MB via the built-in analog/digital conversion circuit. At step 835, the counter FS
The sensitivity 0 of the second detection means 9b of the memory MB corresponding to the value of EL is stored at address VHADRl of the register MADR. At step 336, counter FSEL is set to N1.
111J, and the counter FSEL is rllll.
If it is not llJ, the next value is set in the counter FSEL in step 337, and the address V is set in the register 1MADR.
The next address V HADR2 following HADRI GC is set, and the process returns to step 333.

By repeating this operation, the counter FSE
The sensitivity VO of the second detection means 9b corresponding to the value of L is the address 1 to 32 of each register M ADR HADR1 to
It is stored in the VlIADR32, and when the counter FSEL reaches rllllllJ, the main routine is returned to.

Note that the sensitivity VO (Vc) of the second detection means 9b corresponding to the value of the counter FSEL is all stored in the RAM 21.

When the execution of the "second detection means sensitivity reading routine" is completed, the "sensitivity setting routine" is called.

Memo IJM in step 341 of the "sensitivity setting routine"
Set the minimum sensitivity difference VMIN @ to C. Normally, this minimum sensitivity difference V) fIN is set to the minimum value that can be controlled by the fabric edge detection device of the sewing machine of this embodiment. In step 342, the 5-bit counter FSEL, which sets the signals input to the ports P3 to P7, is set to an initial value of "00000J," and the register MHADR is a memory that stores the outputs of the first detection means 9a and the second detection means 9b. First address V HADR
I and the register M LADR is set to the first address V LADRI of the memory storing the lower cloth sensitivity.

This completes the initial address setting. Step 34
The sensitivity difference between the first detection means 9a and the second detection means 9b at the address set in step 3 is calculated and stored in the memory MD. It is determined whether the sensitivity difference stored in the memory MD calculated in step 344 is larger than the minimum sensitivity difference V MIN of the memory MC, and if it is larger, the value of the memory MD is updated to the value of the memory MC in step 345, and the value of the memory MD is updated to the value of the memory MC. The value of counter FSEL is input to memory ME.

When the sensitivity difference stored in the memory MD is less than or equal to the minimum sensitivity difference V)IIN in the memory MC, the process of step 346 is entered. At step 346, counter FSEL is set to “11111J”.
, and the counter FSE[ is "1111".
1", the next value is set in the counter FSEL in step 347, and the address VHADRI and VHADRI are set in the register MHADR and register MLADR, respectively.
The next address V HA [ ) R2 and address V LADR2 following LADRI are set, and the process returns to step 343 . By repeating this operation, the first detection means 9a and the second detection means 9a
The maximum sensitivity difference with the detection means 9b is calculated and input into the memory MC. If the flag VSEL is rllllllJ,
In step S48, the value of the memory MC is the minimum sensitivity difference VHIN.
Determine whether the value of the memory MO is greater than the minimum sensitivity difference V
If it is less than HIN, an error is displayed by repeating blinking in step 351, and if it is larger, as shown in FIG. 8, the center of the sensitivity difference is calculated in step 349 and it is set as the material edge detection threshold VTHI. and stores it in the RAM 21. In step 350, the display lamp 20 is lit continuously to notify the end of sensitivity setting.

That is, the transmission of the detection light through the lower cloth C obtained by executing the "first detection means sensitivity reading routine" ff1lVd
and the transmission IV of the detection light passing through the lower cloth C and the upper cloth A obtained by executing the "second detection means sensitivity reading routine"
The cloth edge detection threshold VTold is obtained by c. This is 5
Memory M E (STEP
I) is stored as the cloth edge detection threshold V, TH1.

Hereinafter, similarly, the end of "A" in Figure 6 (a>) is shown in Figure 7 (
The position corresponds to b), and the transmission ff1Vb of the detection light that passes through the lower cloth C and the stitched combination mB obtained by executing the "first detection means sensitivity reading routine" and the "second detection means sensitivity reading routine" Transmission ff of the detection light that passes through the upper fabric A to the lower fabric C and the matching fabric B, which have been increased by 1q by executing ``
The cloth edge detection threshold VTH2 is increased by 1q by 1Va.

This is the memory M E addressed by 5TEP2.
(STEP 2) is stored as the cloth edge detection threshold value V-thread H2. Also, the end of "A" in Figure 6(a) is shown in Figure 7(C).
The transmission amount vb of the detection light that passes through the lower fabric C and the sewn-together fabric B obtained by executing the ``first detection means sensitivity reading routine'' and the ``second detection means sensitivity reading routine'' The cloth edge detection threshold value VTH3 is obtained from the transmission IVa of the detection light that passes through the upper cloth A at the lower t5C and the combined mB obtained by executing ``. This is 5TEP
It is stored in the memory M E (STEP 3) addressed in step 3 as the cloth edge detection threshold VTH3.

Then, the "one" end in FIG. 6(a) becomes the position corresponding to FIG. 7(d), and the detection through the lower cloth C obtained by executing the "first detection means sensitivity reading routine" The cloth edge detection threshold V TH2 is obtained by the amount of light transmitted Vd and the amount VC of the detection light transmitted through the lower cloth C and the upper cloth A obtained by executing the "second detection means sensitivity reading routine". is the memory M E addressed by 5TEP4
(STEP 4) is stored as the cloth edge detection threshold V TH2. Also, the end of "work" in Fig. 6 (a) is shown in Fig. 7 (
e), the transmission amount Vd of the detection light passing through the lower cloth C obtained by executing the "first detection means sensitivity reading routine" and the "second detection means sensitivity reading routine"
The cloth edge detection threshold value V TH2 is obtained by the transmission IVC of the detection light transmitted through the lower cloth C and the upper cloth A obtained by performing the above. This means that the cloth edge detection threshold 't/T)f is stored in the memory M E (STEP5) addressed in 5TEP5.
It is stored as 2.

In this way, as shown in the overall explanatory diagram of the cloth edge detection threshold value VTHn stored in the memory M E (STEPn) corresponding to the sewing of this embodiment shown in FIG. The relationship between STEPn> and the cloth edge detection threshold VTHn is obtained.

As mentioned above, 15 edge detection thresholds iF! 1VTl
When the relationship with "In" is set and the predetermined number of 5 TEPs, for example "6" in this embodiment, is set in the memory, the "sewing routine" shown in FIG. 14 is called.

In step 361, it is determined whether the sensitivity settings for all 5 TEPs have been completed, and if the sensitivity settings have not been completed, step 362
The display LED 20, which indicates a sensitivity setting error, flashes. Also, when the sensitivity setting of all S lower EP is completed,
In step S63, STEP is set to "1", and in step 364, the memory ME addressed by 5TEP2 is set.
Cloth edge detection threshold VTH2 stored in (STEP 2)
is called, and the point at which the value changes to below the cloth edge detection threshold value VTH2 is determined as the cloth edge for sewing. At step 365 foot switch 3
7 is detected, the step motor 33 and the upper shaft motor 36 are driven in step 366 according to control conditions (not shown) set on the operation panel 1B. and,
The process stops at step 867 until the transmitted amount VO of the detection light of the first detection means 9a or the second detection means 9b exceeds the cloth edge detection threshold value V1H2, and the first detection means 9a or the second detection means 9b The process remains at step 368 until the transmitted amount vO of the detection light becomes less than or equal to the cloth edge detection threshold VTHI.
As a result, when the value falls below a predetermined threshold, step S
69 "Cloth edge correction routine" is called. Since the "fabric edge correction routine" is not directly related to the gist of the present invention, a detailed explanation thereof will be omitted, but the step motor 33 and It controls the upper shaft motor 36. After executing this “cloth edge correction routine”, step 3
At step 70, the step motor 33 and the upper shaft motor 36 are brought to a halt. In step 371, it is determined whether the 5TEP number is the 5TEP number in the memory FIN, which means the end of sewing,
If it is not the 5TEP number of memory FIN, step 372
The current 5TEP number is incremented by "1" and the routine from step 364 is repeatedly executed. Further, when the number of 5TEPs matches the number of 5TEPs in the memory FIN indicating the end of sewing in step 871, thread trimming processing is performed in step 373, and this routine is exited.

As described above, the fabric edge detection device of the sewing machine of this embodiment includes a first detection means 9a and @2 A plurality of detection means consisting of detection means 9b etc., and a plurality of fabrics to be sewn interposed between the light emitting elements 5, 6 and the light receiving elements 7, 8, each of a single fabric and a plurality of combined fabrics. Sensitivity setting switch 1 instructs to read the amount of transmission of
9 reading instructing means, and the reading instructing means, the lower cloth C interposed between the light emitting element 5.6 and the light receiving element 7.8, and the overlapping lower cloth B and upper '45A. The reading of the amount of permeation for each sewing section is
Each of the detection means 9a according to the sewing order for each sewing section such as "Tsu", "Work", etc.

A reading storage means for storing the read permeation amount, and a continuous sewing order stored in the storage means. Threshold setting means for setting a cloth edge detection threshold based on the difference between the transmission amount for each sewing section recorded according to
Since the device is equipped with a threshold setting means for storing the cloth edge detection threshold value VTHn for each "T" and "Work", in this embodiment, the sewing section "A", " Memory ME (S
By calling the fabric edge detection threshold value VTHn of TEPn), fabric edge detection can be performed for each of the sewing sections "A", "I", "TS", and "r". Therefore, even when multiple pieces of cloth are stacked, the sewing sections "A" and "I" according to the sewing order
, ``Tsu'', ``Sewing work can be automated by setting the cloth edge detection threshold ■Hn for each work J. This can be an embodiment of the first invention.

It also includes light emitting elements 5, 6 and light receiving elements 7.8 for detecting the light projected from the light emitting elements 5, 6, and detecting means 9a, 9b for detecting the amount of light transmitted through the cloth to be sewn. , a reading instruction means consisting of a sensitivity setting switch 19 for instructing the detection means 9a, 9b to read the light transmission 2 of the cloth to be sewn; Based on the amount of light transmitted through the cloth to be sewn detected by 9a and 9b, the presence or absence of the target cloth is determined as in step 367 and step 368 in FIG.
, Detecting "None" @ Seikima "A", "I", "Tsu",
Threshold setting means for setting the cloth edge detection threshold VTHn for each "work"; and a memory M E (ST
The storage means stored in EPn) compares the threshold set by the threshold value setting means and the amount of light transmitted by the detection means 9a, 9b, and determines the amount of light transmitted by the target cloth "r*J, r absent". When the determination result of the cloth determining means and the cloth determining means changes from "present" to "absent" as in steps 367 and 868 in FIG.
An embodiment of the second invention may include a cloth edge determining means that changes 5 TEP to change the cloth edge detection threshold value VTHn or performs thread cutting.

In the above embodiment, the lower cloth 23 is interposed between the light emitting element 5 and the light receiving element 7 constituting the first detection means 9a,
By simply interposing the upper cloth A overlapping the lower cloth C and the combined cloth B sewn with the lower cloth C between the light emitting element 6 and the light receiving element 8 constituting the second detection means 9b, the lower cloth Since the cloth edge detection threshold can be set based on the difference in the amount of transmission between the lower cloth C and the upper cloth A overlapped with the sewn laminate cloth B, only one operation of the reading instruction means is required. This simplifies the multiple operations for each sewing section for setting the fabric edge detection darkness value.

Although not disclosed in the flowchart of FIG. 14, the memory M E (ST
The starting point can also be determined by using the cloth edge detection threshold of the starting point of the sewing section "A" of EPn).

By the way, the light emitting element 5 and the light receiving element 7 constituting the first detecting means 9a in the above embodiment, and the light emitting element 6 and the light receiving element 8 constituting the second detecting means 9b are each an independent pair of light emitting element and light receiving element. However, when carrying out the present invention, the light-emitting element and/or the light-receiving element can be used in common by using a prism, a half mirror, or the like, or by mechanically separating the lights. In addition, the first detection means 9
Although two pieces a and second detection means 9b are used,
When implementing the present invention, the reliability of the cloth edge detection darkness value can be increased by using two or more detection means and a plurality of detection means.

Further, the light emitting element 5.6 and the light receiving element 7 of the above embodiment,
The first detection means 9a and the second detection means 9b read the amount of transmission of each of the lower cloth C interposed between the lower cloth 15C and the upper cloth A overlapped with the sewn combined cloth B. The reading/storage means for storing the read transparent end is prepared with a memory having a capacity specified by the 5-bit AT/NO. There are no limitations, as long as the response can be done with high reliability. For example, it is also possible to feed the upper cloth A overlapping the lower cloth C and the combined cloth B sewn together with the lower cloth C by a predetermined distance vertically or horizontally at the time of detection.

Threshold setting means for setting a cloth edge detection threshold based on the difference in transmission amount between the lower cloth stored in the storage means of the above embodiment and the lower cloth and upper cloth overlapped with each other includes the first detection means and the second detection means. The cloth edge detection threshold is set at the center between the output of the detection means and the amount of transmission, but when carrying out the present invention, one of the transmission amounts should be set in consideration of changes in the thickness, density, color, etc. of the cloth. It can be brought closer to the quantity side.

Further, the threshold setting means for setting the cloth edge detection threshold based on the transparent edge of each l sewing section stored in the continuous sewing order stored in the storage means of the above embodiment is configured to set the cloth edge detection threshold for sewing sections "A", "
Although nine memories are prepared in the following description, the number of sewing sections is not limited to a predetermined number, but can be set arbitrarily. be able to.

[Effects of the Invention] As described above, the fabric edge detection control device for a sewing machine according to the first invention is capable of detecting a single piece of fabric of a plurality of fabrics to be sewn interposed between a light emitting element and a light receiving element constituting a plurality of detection means. or reading instruction means for instructing reading of the amount of transmission of each of a plurality of cloths combined; reading and storing means for sequentially reading the amount of permeation by each of the detection means according to the sewing order for each sewing section and storing the read amount of permeation in the recording means; and the continuous sewing order stored in the storage means. and threshold value setting means for setting a cloth edge detection threshold value based on the transmitted amount for each sewing section stored according to the method.

Therefore, by recalling the cloth edge detection threshold value in the storage means for each sewing section specified by the threshold value setting means, it is possible to detect the cloth edge for each sewing section, and even when multiple pieces of cloth are overlapped, the sewing order A cloth edge detection threshold can be set for each sewing section according to the following, and sewing work can be automated.

In addition to the effects of the above invention, the fabric edge detection control device for a sewing machine according to a second aspect of the invention instructs the reading instruction means to read the amount of light transmitted through the cloth to be sewn; Based on the amount of light transmitted through the cloth to be sewn, which is detected by the detection means in response to the instruction, the threshold value setting means determines whether the target cloth is present or not.
, setting a threshold value for detecting "absence", storing it in a storage means according to the sewing order, and comparing the threshold value set by the threshold value setting means with the amount of transmitted light detected by the detection means during operation of the sewing machine; Since it is a device that determines whether the target cloth is "present" or "absent," the judgment result of the cloth discriminating means changes from "present" to "
When it changes to "No", it can be determined that it is a cloth edge, and in the middle,
Even if multiple pieces of fabric overlap, the operation of the sewing machine can be controlled simply by setting the final threshold value.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the electrical configuration of a material end detection control device for a sewing machine according to an embodiment of the present invention, and FIG. 2 shows a detection means of a material end detection control device for a sewing machine according to an embodiment of the present invention. 3 is a side view of the main part of the detection means shown in FIG. 2, and FIG. 4 is a front view of the main part of the detection means shown in FIG. An explanatory diagram showing the plane positional relationship with the fabric, FIG. 5 is a front view of the main part showing the panel of the fabric edge detection control device of the sewing machine according to one embodiment of the present invention, and its circuit configuration diagram, and FIG. 6 is the present invention. FIG. 7 is an explanatory diagram showing the order in which multiple pieces of cloth are sewn in an embodiment of the present invention. FIG. 8 is an explanatory diagram showing the order in which cloth is sewn in an embodiment of the present invention. 9 to 14 are flowcharts of the fabric edge detection control device I of the sewing machine according to the embodiment of the present invention. In the figure, 5.6: Light emitting element 7, 8: Light receiving element 9a: First detection means 9b = Second detection means 10: Microcomputer 19: Sensitivity setting switch A, A, T, M: Sewing section. In the drawings, the same reference numerals and the same symbols indicate the same or equivalent parts. Patent applicant Aisin Seiki Co., Ltd.

Claims (2)

[Claims] (1) A detection means consisting of a light-emitting element and a light-receiving element that detects light projected from the light-emitting element, and a plurality of cloths to be sewn interposed between the light-emitting element and the light-receiving element, either alone or in combination. a reading instruction means for instructing to read the amount of transmission of each of a plurality of cloths; and the reading instruction means reads the amount of transmission of each of the one or more cloths interposed between the light emitting element and the light receiving element. reading and storing means for sequentially reading the information by each of the detection means according to the sewing order for each sewing section, and storing the read transmission amount in the storage means; 1. A fabric edge detection control device for a sewing machine, comprising: threshold setting means for setting a fabric edge detection threshold based on the amount of penetration in each sewing section. (2) a detection means that has a light emitting element and a light receiving element that detects the light projected from the light emitting element, and detects the amount of light transmitted through the cloth to be sewn; a reading instruction means for instructing to read the amount of light transmitted; and a reading instruction means that operates according to the instructions of the reading instruction means, and selects a target cloth based on the amount of light transmitted through the cloth to be sewn detected by the detection means. a threshold value setting means for setting a threshold value for detecting "presence" or "absence" of the threshold value; a storage means for storing a plurality of threshold values set by the threshold value setting means according to the sewing order; and a threshold value set by the threshold value setting means. A cloth determining means compares the amount of transmitted light detected by the detecting means and determines whether the target cloth is "present" or "absent", and the determination result of the cloth determining means changes from "present" to "absent". A fabric edge detection control device for a sewing machine, comprising: fabric edge determining means for determining that the fabric edge is present when the change occurs.