JPS6244287A - Clamp-stitch apparatus of sewing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a sewing machine that selectively forms various types of patterns according to stitch data from a pattern memory, and more specifically, the present invention relates to a sewing machine that selectively forms various types of patterns according to stitch data from a pattern memory. The present invention relates to a tacking device that automatically performs tacking.

[Prior Art] Conventionally, in order to perform tacking stitches, a method is known in which an operating body provided exclusively for a sewing machine is operated at a desired location in a pattern. On the other hand, for one-cycle patterns such as decorative patterns and character patterns, tacking is automatically performed at predetermined locations in the pattern, for example, at the beginning and end of the pattern, regardless of manual operation. In this latter case, a plurality of stitch data for forming tacking stitches are stored in advance in the pattern memory along with stitch data for forming the main body portion of each pattern. Therefore, the stitch data for the tacking stitch along with the stitch data for the main body of the pattern are read out from the pattern memory in a predetermined order in synchronization with the vertical movement of the sewing needle, and the entire pattern in one cycle including the tacking stitch is read out from the pattern memory in a predetermined order. It is formed.

[Problems to be Solved by the Invention] However, in a conventional device that automatically performs tacking stitches, a plurality of stitches for tacking stitches are stored in the pattern memory along with a large number of stitch data for the main body of the pattern. Since the data is stored in advance for each pattern, if the above-mentioned conventional system is adopted in a computerized sewing machine that can form many patterns of over 100 types, it is possible to store data in the pattern memory using only the stitch data of the tacking stitches. This will occupy a lot of storage space. For this reason, in conventional devices, it is necessary to use a relatively large-capacity pattern memory, and the instruction data is also used to perform other special operations other than pattern formation, such as automatic guidance for sewing preparation work. Installing additional memory for storing the information is limited in terms of space and cost of the sewing machine.

[Object of the Invention] Therefore, the present invention has been made to solve the problems of the conventional device described above. The purpose is to reduce the storage area of a memory such as a pattern memory occupied by the execution commands as much as possible, and to make it possible to add instruction data for executing sewing machine functions other than pattern formation.

[Means for solving the problems] In order to achieve the above-mentioned object, the tacking device of the present invention has the following features:
A tacking memory stores control commands for executing tacking, and tacking is performed by detecting that stitch formation has progressed to a predetermined stitch formation position in each pattern to execute tacking. a detection means for generating an execution signal; and a predetermined number of stitch data for tacking according to the control command in the tacking memory, and generating stitch data for tacking in response to generation of the tacking execution signal. and control means for interpolating stitch data from the pattern memory and supplying the stitch data to a driving means for a stitch forming mechanism.

[Operation] While the desired pattern selected from among many types of patterns is being formed by the pattern selection means in accordance with the stitch data from the pattern memory, the detection means detects whether the current stitch forming position is within the desired pattern. At the step, it is determined whether or not the stitch forming position is predetermined for executing the tacking stitch, and when the stitch formation progresses to the predetermined stitch forming position, a tacking stitch execution signal is generated.

Then, the control means creates a predetermined number of stitch data for tacking according to the control command stored in the tacking memory,
In response to generation of the tacking execution signal, reading of stitch data from the pattern memory is stopped and stitch data for the tacking stitch is supplied to the driving means. Thereby, the stitch forming mechanism forms a predetermined number of tacking stitches subsequent to forming the main body of the desired pattern.

[Embodiment] An embodiment of the tacking device of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the electrical configuration of a sewing machine employing the tacking device of this embodiment. In Figure 1,
The pattern specifying device 10 is a known device that includes a plurality of pattern selection switches for inputting the pattern number of each pattern and an encoder that generates a pattern code PC of a desired pattern according to the switch devices. The start address memory 12 receives a start address signal PAD for designating the address of the pattern memory 14 (described later) in which the first stitch data related to the pattern is stored, and a start address signal PAD for specifying the address of the pattern memory 14, which will be described later, in which the first stitch data related to the pattern is stored, and the start of the pattern stored next to the pattern related to this address signal PAD. Address signal NA
D and are stored in pairs for each pattern, and are configured to output head address signals PAD and NAD, respectively, in accordance with the pattern code PC from the pattern specifying device 10. In this embodiment, the pattern selection means is comprised of the pattern specifying device] O1 head address memory 12 and the rear) book tacking necessity determination circuit 40. Data reading device 16
is configured as data reading means and has an address counter for specifying each address of the pattern memory 14. The address counter is configured to load the start address signal PAD when a pattern is selected and when a pattern end signal PED is generated from the pattern memory 14. Further, the data reading device 16 determines whether the selected pattern is a repeatedly formed practical pattern such as a straight seam or a one-cycle pattern such as a character pattern based on the pattern code PC,
The sewing machine is configured to output a stop command signal STP for stopping the sewing machine to an operation stop command circuit 18, which will be described later, when the pattern end signal PED is generated when the sewing machine is determined to be a one-cycle pattern. timing signal generator 20
is configured to generate a timing pulse TP at a position where the sewing needle is slightly lower than the sewing machine bed surface MB as shown in FIG. 5, and the timing pulse TP is delayed by a short time by a delay circuit 22. It is supplied to the data reading device 16 via the AND circuit 24 as the data reading timing signal DTP.

The address counter in the data reading device 16 is configured to count the data read timing signal DTP and output the counted contents to the input port P of the multiplexer 26 as an address signal TAS. [Pattern memory] 4 stores a large number of stitch data regarding each of a large number of practical patterns and one-cycle patterns in a predetermined order, and also outputs one bit of data following the final stitch data for each pattern as a pattern end signal PED. According to the address signal output from the multiplexer 26, each stitch data is supplied to the input port P1 of the multiplexer 28. The stitch data that has passed through the multiplexer 28 is supplied to the drive circuit 30.
is configured to drive the needle swing actuator 32 and feed actuator 34 in accordance with stitch data. The needle swing actuator 32 is driven to control the lateral swing position of the sewing needle, and the feed actuator 34 is driven to control the adjustment position of a feed adjuster (not shown), thereby controlling the feed movement of the feed dog.

In this embodiment, the drive circuit 30 and both actuators 32, 34 constitute the drive means.

Next, the electrical configuration related to the execution of tacking will be explained.

The securing stitch necessity determination circuit 40 determines whether or not the selected pattern is a one-cycle pattern that requires securing stitching based on the pattern code PC, and when it is determined to be a one-cycle pattern, sends a high-level securing stitch control signal @BTS. When it is determined that the pattern is not a one-cycle pattern, a low-level stop line control signal BTS is output to the AND circuit 42. The operation stop command circuit 1B has an operation switch that can be operated to start and stop the sewing machine, and in response to each operation of the operation switch, it outputs a high-level signal that is an operation command signal and a stop command signal. It is configured to alternately generate a certain low level signal. Further, the command circuit] 8 is configured to output a low level signal regardless of the operation of the operation switch when the stop command signal 8 P is supplied from the data reading bag @16. The output signal from the command circuit 18 is supplied to a sewing machine motor control device (not shown) and used to start and stop the sewing machine motor. Furthermore,
The output signal from the command circuit 1B is also supplied to an AND circuit 42, and the AND circuit 42 passes the stop line control signal BTS while the command circuit 18 is supplying a high-level signal that is a driving command signal. The signal is supplied to a detection device 44. The detection device 44 detects when the stitch formation progresses to a predetermined stitch formation position for executing the tacking stitch. There was a 1.77 sweep with Mimu Fukuda who picked up a 7 and a 1.77 sweep. The detection device 44 then detects the start address signal PAD from the start address memory 12.

NAD, the timing pulse TP from the timing signal generator 20, and the tacking control signal @BTS from the tacking/unfastening judgment circuit 40 via the AND circuit 42 are supplied, and based on these signals, the second The operations according to the flowchart shown in the figure are performed, and as a result, the first to third tacking execution messages @DP1°DP2. It is configured to output DP3.

The tacking data creation device 46 receives the first data from the detection device 44.
and second tacking execution signal DP1. DP2, the start address signal NAD from the start address memory 12, the tie stitch control signal BTS from the AND circuit 42, and the stitch data from the pattern memory 14 are supplied, and based on these signals and data, The sewing machine is configured to perform operations according to the flowchart shown in FIG. 3 in response to control commands stored in a tacking execution control memory 48 serving as a tacking memory. As a result of this operation, the tacking stitch data creation device 46 creates stitch data BSD for tacking stitches, temporarily stores it in the data register 50, and then creates a stitch data BSD for the tacking stitch to temporarily store it in the data register 50. The address signal is supplied to the input port P2 of the multiplexer 26, and the port selection signal PC3 is supplied to the boat selection terminal of the multiplexer 26. The first from said detection device @44
and second tacking execution signal DP1. DP2 is OR circuit 5
2 to the J terminal of a J- type flip-flop 54, to which a timing pulse TP is supplied. The flip-flop 54 is configured to output a port selection signal @PSD for selecting the input port of the multiplexer 28 from its Q terminal, and a signal @GS for controlling opening/closing of the AND circuit 24 from its Q terminal. ing. The AND circuit 24 is further supplied with a third tacking execution signal DP3 from the detection device 44. Note that the multiplexers 26 and 28 select the input port P1 when the boat selection signals PC3 and PSD are at low level.
When the level is high, the input port P2 is selected and the signal or data of the selected input port is output.

The control means in this embodiment includes an AND circuit 24°42,
Multiplexer 26, 28, tacking data creation device 46
, an OR circuit 52 and a flip-flop 54.

The operation of the sewing machine equipped with the tacking device constructed as described above will be described below.

Pattern designation device 1 for forming straight seams in practical patterns
When a straight stitch is specified by operating the pattern selection switch in 0, the pattern specifying device 10 outputs the pattern code PC of the straight stitch to the start address memory 12, data reading device 16, and tacking/unfastening judgment circuit 40, respectively. The start address memory 12 stores the start address signal PAD of the straight stitch,
The pattern stored next to the straight stitch, for example, the start address signal NAD of the zigzag stitch, is outputted to the data reading device 16, the detection device 44, and the tacking stitch data creation device 46, respectively. Then, the fastening stitch determination circuit 40 determines that the selected straight stitch is not a one-cycle pattern and outputs a low-level fastening stitch control signal BTS to the AND circuit 42, and the data reading device 16 The start address signal PAD of the stitch is loaded into an internal address counter, and the start address signal PAD is outputted to the input port P1 of the multiplexer 26 as an address signal TAS.

On the other hand, the flip-flop 54 is automatically reset when the sewing machine is powered on, or the timing pulse T
Since it is reset for each stitch formation in response to P, it is in the reset state when a pattern is selected, and a high level signal GS is applied from the QDa terminal to the AND circuit 24, and a low level signal is output from the Q terminal. A port selection signal PSD is output to the boat selection terminal of the multiplexer 28. As a result, the multiplexer 28 is in a state where the input port P1 is selected.

Here, in order to operate the sewing machine, the operation stop command circuit 18
When the operation switch is operated, the command circuit 18 outputs a high-level operation command signal to the AND circuit 42, and also supplies the command signal to the sewing machine motor control device to start the sewing machine motor. Then, the AND circuit 42 passes the low-level fastening line control signal BTS and supplies it to the detection device 44 and the fastening data creation device 46, respectively. The detection device 44 detects the stop line control signal BTS.
is at a low level while step RD1. shown in FIG. R.D.
2 is repeatedly executed, and the third tacking execution signal DP3 is set to high level and is supplied to the AND circuit 24. At this time, the first and second tacking execution signals DP1. Since DP2 is at a low level, the flip-flop 54 maintains the reset state and continues to supply the high level signal GS to the AND circuit 24, and the AND circuit 24 passes the data read timing signal DTP from the delay circuit 22. is in a state that allows

The tacking stitch data creation device 46 also outputs a tacking line control signal B.
Step RB1. shown in FIG. 3 while TS is at a low level.
Repeatedly execute RB2 and set the low level boat selection signal PC.
3 continues to be supplied to the boat selection terminal of multiplexer 26. As a result, the multiplexer 26 input port P1
is selected and the address signal TA from the data reading device 16 is selected.
S to the pattern memory 14, which sends the first stitch data for straight stitches to the multiplexer 26.
is supplied to the drive circuit 30 via.

The drive circuit 30 drives the needle swing actuator 32 according to the first stitch data of the straight stitch, more specifically, according to the needle swing data in the stitch data, and determines the swing position of the sewing needle.

Thereafter, when the sewing machine motor is started and the sewing needle reaches a predetermined position below the sewing machine bed surface, the timing signal generator 20 generates a timing pulse TP and the detection device 44
and the flip-flop 54. However, the detection device 44 continues to execute steps RD1 and RD2 described above regardless of the occurrence of the timing pulse TP, and the flip-flop 54 also continues to maintain the reset state. Further, the timing pulse TP from the timing signal generator 20 is also supplied to a delay circuit 22, and the delay circuit 22 supplies the data read timing signal @D T P to the data read device 16 via an AND circuit 24, Increments the internal address counter by 1.

Address signal TAS, which is the count content of the address counter
is supplied via multiplexer 26 to pattern memory 14, which outputs second stitch data for straight stitches. The second stitch data is supplied to the drive circuit 30 via the multiplexer 28, and the drive circuit 30 operates the feed actuator 34 according to the second stitch data, in particular, according to the feed data in the stitch data. to determine the adjustment position of the feed adjuster. After determining the position of the feed adjuster, when the sewing needle reaches a predetermined position above the sewing machine bed surface, the drive circuit 30 drives the needle swing actuator 32 according to the needle swing data in the second stitch data. to determine the swing position of the sewing needle. Thus, the known positioning operation of the feed adjuster and the sewing needle is repeated until the pattern end signal PED is output from the pattern memory 14. When the pattern end signal PED is output, the data reading device 16 loads the straight stitch start address signal PAD into the address counter again, and then determines the pattern code PC. In this case, since the pattern code PC corresponds to a straight stitch and does not correspond to a one-cycle pattern, the data reading device 16 does not generate the stop command signal STP. For this reason, the pattern memory 14
The stitch data is read out continuously from , and straight stitches are successively formed as described above. The formation of this straight stitch is stopped by operating the operation switch of the operation stop command circuit 18 to stop the sewing machine motor.

For practical patterns such as straight stitches, locking can be performed at a desired location of the practical pattern by operating a locking switch provided exclusively on the sewing machine.

In order to form a one-cycle pattern instead of forming a practical pattern, the pattern specifying device 10 is activated at time TS shown in FIG.
When a desired one-cycle pattern is specified by operating the pattern selection switch, the pattern specifying device 10 outputs the pattern code PC to the start address memory 12, and the start address memory 12 outputs the start address signal PAD to the data reading device 16.
Output to. The data reading device 16 uses the first address signal P.
AD is loaded into the address counter and is also supplied to the input port P1 of the multiplexer 26 as the address signal TAS. Further, the tacking line determination circuit 40 determines whether tacking is necessary according to the pattern code PC, and supplies a high level tacking line control signal BTS to the AND circuit 42.

Operation stop command circuit 1 to form a one-cycle pattern
When the operation switch 8 is operated, the command circuit 18 outputs a high-level operation command signal to start the sewing machine motor, and also sends the command signal to the AND circuit 42.
supply to. The AND circuit 42 passes the high-level fastening line control signal BTS and supplies it to the detection device 44 and the fastening data creation device 46, respectively. As a result, the detection device 44 determines the high level of the stop line control signal BTS in step RD1 shown in FIG. 2 and executes step RD3, but repeatedly executes step RD2 until the timing pulse TP is generated. While outputting the first and second tacking execution signals DPI and DP2 at a low level,
The third tacking execution signal DP3 is set to high level and output. Similarly, the tacking stitch data creation device 46 also determines the high level of the tacking line control signal BTS in step RB1 shown in FIG. 3, resets the internal counter C2 in step RB3, and resets the boat selection signal PC3 in step RB4. At step RB5, the address signal designating the address (NAD-2> of the pattern memory 14, that is, the address (m+n) shown in FIG. 4) is sent to the input port P2 of the multiplexer 26. The address signal supplied via this multiplexer 26 causes
The pattern memory 14 generates final stitch data, specifically needle swing data ZAn, which is the stored content at address (m+n), and inputs it to the tacking stitch data creation device 46. Then, the tacking data creation device 46 performs step RB6. At RB7, the level of the first tacking execution signal DP1 and the count contents of the internal counter C2 are determined, and steps RB4 to RB7 are repeatedly executed until the execution signal DPI becomes high level. During this time, the multiplexer 28 receives the boat selection signal PSD at a low level since the flip-flop 54 is in the reset state, and supplies the final stitch data from the pattern memory 14 to the drive circuit 30. Drive circuit 30
Since the sewing needle is above the sewing machine bed surface immediately after the pattern is selected, that is, at time TS shown in FIG. Set the swing position to the same position as the swing position of the last needle of the one-cycle pattern.

When the sewing needle set at the final needle swing position descends from the sewing machine bed surface and reaches a predetermined position in order to form the first stitch of the one-cycle pattern, the timing signal generator 20 outputs a signal as shown in FIG. The detection device 44 generates a timing pulse TP at a time point T1 shown in FIG. DP1 is temporarily set to a high level and outputted to the tacking data creation device 46, and also supplied to the flip-flop 54 via the OR circuit 52, and then in step RD6. until the next timing pulse TP is generated. Repeat RD7. The flip-flop 54 outputs a high-level first tacking execution signal DP1.
, outputs a high-level boat selection signal PSD to cause the multiplexer 28 to select input port P2, and outputs a low-level signal GS to prohibit the AND circuit 24 from passing the data read timing signal DTP. Further, the tacking stitch data creation device 46 performs step R.
In step B6, it is determined whether the first tie stitch execution signal jMDP1 is at a high level, and in step RB8, the internal counter C2 is
The count content of the internal counter C2 is incremented by 1 to change from "0" to "1", and the count content of the internal counter C2 is determined in step RB9. At this point, internal counter C2
is "1", the tacking stitch data creation device 46 refers to the needle swing data ZAn from the pattern memory 14 in step RB10 to create tacking stitch data BSD, and in step RB11 the tacking stitch data BSD is created. The stitch data BSD that has been created is output and temporarily stored in the data register 50, and steps RB4 to RB7 are repeatedly executed until the first tie stitch execution signal DP1 becomes high level again. The stitch data BSD for tacking stitches created this time consists of needle swing data ZAn in the final stitch data and feed data for commanding minute backward feed, as shown in Fig. 4. Stitch data BSD for tacking is supplied from the data register 50 to the drive circuit 30 via the multiplexer 28. The drive circuit 30 drives the feed actuator 34 in accordance with the feed data in the stitch data BSD for tacking stitches at a time when the sewing needle is below the sewing machine bed surface, that is, immediately after time T1 shown in FIG. 5, to perform a minute backward feed. At time T2 shown in FIG. 5, when the feed adjuster is positioned at the adjustment position for and the sewing needle rises above the surface of the sewing machine bed, the needle swing data ZA in the stitch data BSD for tacking is set.
The needle swing actuator 32 is driven in accordance with n to again set the swing position of the sewing needle to the same position as the swing position of the final needle.

As a result, the stitches of the second needle of the one-cycle pattern are formed at the swing position of the final needle after the minute backward feeding movement is performed.

When the timing signal generator 20 generates the second timing pulse TP at time T3 shown in FIG. 5, the detection device 44 determines the generation of the timing pulse TP in step RD6, and counts the internal counter C1 in step RD8. The content is incremented by 1 to change rOJ to "1", and the count content of the internal counter C1 is determined in step RD9. At this time, internal counter C
Since the count content of 1 is "1", the detection device 44 executes step RD10 to execute the first tie stitch (No. i DP1).
is temporarily set to a high level and output to the tacking data creation device 46. The tacking data creation device 46 determines the high level of the first tacking execution signal DP1 in step RB6, and sets the internal counter C2 to "1" in step RB8.
” to “2”, and after determining the count contents of the internal counter C2 in step RB9, step R
Execute B12. In step RB12, the securing stitch data creation device 46 creates stitch data BSD for securing stitches consisting of the needle swing data ZAn of the pattern memory 14 and feed data for commanding slight forward feed, and in step RB11. The stitch data BSD is output and stored in the data register 5Q. Then, the flip-flop 54 maintains the set state by outputting the first tie stitch execution signal DP1 at a high level, and selects the input port P2 of the multiplexer 28 so that the stitch data BSD from the data register 50 can pass through. continue.

The drive circuit 30 operates at the time point T shown in FIG.
Immediately after step 3, the feed actuator 34 is driven to set the feed adjuster to the adjustment position for slight forward feed, and the time point shown in FIG. At T4, the needle swing actuator 32 is driven to set the sewing needle swing position to the final needle swing position. As a result, the stitch of the third needle of the one-cycle pattern is formed at the swing position of the final needle after the minute forward feeding movement is performed.

After the tacking stitches consisting of three stitches have been executed as described above, the timing signal generator 20 outputs the timing signal at time T5 shown in FIG.
When the timing pulse TP is generated in step R, the detection device 44 detects the generation of the timing pulse TP in step R.
It is determined in D6, the internal counter C1 is changed from "1" to "2" in step RD8, the count content of the internal counter C1 is determined in step RD11, and step RDI 2 is executed. This step RDI
2, the detection device 44 sets the third tacking execution signal DP3 to a low level for a predetermined period of time that can inhibit the data readout timing signal DTP from the delay circuit 22 from being supplied to the data readout device @16. and closes the AND circuit 24. As a result, the count content of the address counter of the data reading device 16 is held at the value of the leading address signal PAD of the selected one-cycle pattern. At this time, the flip-flop 54 is reset by the generation of the timing pulse TP and outputs a low-level port selection signal PSD to cause the multiplexer 28 to select the input port P1. On the other hand, the tacking data creation device 46 performs step RB13. Repeating RB14, its step R
At B13, the port selection signal PC3 is set to low level and output, causing the multiplexer 26 to select the input port P1. Therefore, the start address signal PAD from the data reading device 16 is supplied as the address signal TAS to the pattern memory 14 via the multiplexer 26, and the pattern memory 14 receives the stitch data at the start address (m+1>) shown in FIG. The feed is supplied to the drive circuit 30 via the multiplexer 28.The drive circuit 30 drives the feed actuator 34 immediately after time T5 shown in FIG. Set the position of the needle, and set the needle swing data ZA in the stitch data.
1, the needle swing actuator 32 is driven at time T6 shown in FIG. 5 to set the swing position of the sewing needle. As a result, the fourth stitch of the one-cycle pattern is formed, and subsequent stitches are formed in the same manner as the fourth stitch according to the stitch data of each address shown in FIG. During this time,
The detection device 44 increments the count content of the internal counter C1 in step RD8 every time the occurrence of the timing pulse TP is determined in step RD6, and transfers the count content to step RD13. The determination is made in RD14, and the above-described determination operation is repeated until the count of internal counter C1 reaches a predetermined value.

After the data reading device 16 specifies the address (m+n-1> shown in FIG. 4 of the pattern memory 14 and reads out the stitch data), at time T7 shown in FIG.
When P occurs, the detection device 44 increases the count content of the internal counter C1 in step RD8, and proceeds to step R.
Execute D13. At this time, the count content of internal counter C1 has reached <n+2), and this content is (NAD-P
AD+1>, the detection device 44 determines this count content in step RD13, and performs step RDI5.
At this point, the second tacking execution signal DP2 is temporarily set to a high level and output. In response to the second tacking execution signal DP2, the flip-flop 54 is set and outputs a high-level port selection signal PSD to cause the multiplexer 28 to select the input port P2, and also outputs the data read timing signal DTP from the delay circuit 22. In order to prohibit passage of the signal GS, a low level signal GS is outputted to open the AND circuit 24. Therefore, the address counter of the data reading device 16 is set to the address (m+) of the pattern memory 14 shown in FIG.
n-1), and the pattern memory 14 stores the stitch data at that address in the lock stitch data creation device @46.
is supplied to. In addition, the tacking data creation device 46 includes:
Step RB
14, the internal counter C2 is increased from "2" to "3" in step RB15, and the content of the count is determined in step RB'16.
Execute step 17. In this step RBI 7, the tacking data creation device 46 creates tacking stitch data BSD consisting of needle swing data ZAn-1 from the pattern memory 14 and feed data for commanding slight backward feeding, In step RB18, the stitch data BSD is output and stored in the data register 50. data register 5
The stitch data BSD of 0 is supplied to the drive circuit 30 via the multiplexer 28, and the drive circuit 30 operates the feed actuator 34 immediately after time T7 shown in FIG. and drives the needle swing actuator 32 according to the needle swing data ZAn-1 at time T8 shown in FIG. is formed after the

Subsequently, when the timing pulse TP is generated at time T9 shown in FIG.
8, the count content of the internal counter C1 is increased from (n+2> to (n+3)), and the count content is determined in step RD13.
Since > is equal to (NAD-PAD+2>), the detection device 44 executes step RD15.Then, the securing stitch data creation device 46 executes the second
The high level of the lock stitch execution signal @DP2 is determined, and the internal counter C2 is changed from "3" to "4" in step RB15.
In step RBI6, the content of the count is determined and step RB19 is executed. In this step RB19, the tacking stitch data creation device 46 creates tacking stitch data BSD consisting of needle swing data ZAn-1 and feed data for commanding slight forward feed, and in step RB20, the tacking stitch data creation device 46 The data BSD is output, and the stop line control signal BTS is determined in step RB21. Since the stop line control signal BTS is at a high level during sewing of a one-cycle pattern, the next step RB22 is performed.
is executed to set the port selection signal PC3 to a low level and output it. Stitch data BSD for tacking created in step RB19 is stored in the data register 50 and then supplied to the drive circuit 30 via the multiplexer 28, and this drive circuit 30 is connected to the drive circuit 30 in FIG. Immediately after the time T9 shown in FIG. 5, the feed actuator 34 is driven, and at the time T10 shown in FIG.
2, thereby driving the (n+4th) one-cycle pattern.
>The stitch of the needle is formed after a small forward feed movement has been performed.

When the timing signal TP is generated at time T11 shown in FIG. 5, the flip-flop 54 is reset;
A low level port selection signal PSD is outputted to cause the multiplexer 28 to select the input port 28, and a high level signal GS is supplied to the AND circuit 24. At this time, the detection device @44 increases the internal counter C1 from (n+3) to (n+4) in step RD8, determines the content of this count in step RDI4, and determines the content of the count (n+4).
is equal to (NAD-PAD+3>, so step R
Returning to DI, in step RD2, the third tacking execution signal DP3 is set to high level and output to the AND circuit 24. Since this AND circuit 24 receives the high level execution signal DP3 and the high level signal GS, the delay circuit 24
The data readout timing signal DTP from 2 is passed through and supplied to the data readout device 16, and the address counter of the data readout device 16 has a count that specifies the address (m+n) shown in FIG. 4 of the pattern memory 14. pattern memory 1
The final stitch data from address (m+n) of No. 4 is supplied to the drive circuit 30 via the multiplexer 28,
The drive circuit 30 outputs the send data FAn when the data read timing signal DTP is generated immediately after time T11 shown in FIG.
At time T12 shown in FIG. 5, the needle swing actuator 32 is driven according to the needle swing data ZAn, and as a result, the needle swing actuator 32 is driven according to the needle swing data ZAn at time T12 shown in FIG. seams are formed.

Thereafter, when the timing pulse TP is generated at time T13 shown in FIG. 5, the data reading device @16 specifies the address (m+n+1) shown in FIG. Receive.

As a result, the data reading device 16 loads the head address signal PAD into the address counter again and supplies the stop command signal STP to the operation stop command circuit 18. The operation stop command circuit 18 outputs a low level stop command signal to the AND circuit 42 to close it, and also supplies the low level stop command signal to the sewing machine motor control device. The sewing machine motor control device performs a known operation to stop the sewing machine motor at time TE shown in FIG. 5 when the sewing needle reaches a predetermined position on the sewing machine bed surface. Thus, tacking is automatically performed at the first and last predetermined locations of the selected one-cycle pattern.

[Modifications] The present invention is not limited to the embodiments described in detail above, and various changes can be made without departing from the spirit thereof.

For example, in this embodiment, the tacking is automatically executed at two predetermined locations at the beginning and end of the one-cycle pattern, but the tacking is automatically executed at the middle location of the one-cycle pattern. may be configured.

Further, in this embodiment, the tacking stitch data creation device 46 responds to the tacking execution signals DP1 and DP2 from the detection device 44 to create stitch data BSD for tacking stitches, and the stitch data BSD is patterned. Although the operation of intervening with the stitch data from the memory 14 is performed, the operation of creating stitch data for tacking stitches may be configured to be performed when a one-cycle pattern is selected.

Furthermore, the entire portion or a portion of the portion surrounded by the dashed line in FIG. 1 may be configured by a microcomputer.

[Effects] The present invention includes a detecting means that detects that stitch formation has progressed to a predetermined seam formation position in order to execute the tacking stitch in each pattern, and generates a tacking execution signal; A predetermined number of stitch data for tacking stitches are created according to the control commands stored in the sewing memory, and the stitch data for tacking stitches is allocated to the stitch data from the pattern memory in response to generation of a tacking execution signal. and a control means for supplying the driving means for the seam forming position. With this configuration, there is no need to individually store stitch data for tacking stitches in the pattern memory for each of a large number of patterns, so the control command for executing tacking stitches can be stored in the sewing machine's memory, including the pattern memory. The storage area occupied can be reduced, and the reduced storage area can be used to perform other sewing machine functions, thereby efficiently improving the functionality of the sewing machine.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the electrical configuration of a sewing machine to which an embodiment of the tacking device of the present invention is applied, FIG. 2 is a flowchart for explaining the operation of the detection device in this embodiment, and FIG. 3 is a flowchart for explaining the operation of the securing stitch data creation device in this embodiment, and FIG. 4 shows stitch data and stitch data for securing stitches stored in the pattern memory regarding the one size sill pattern in this embodiment. Memory map FIG. 5 is a timing chart showing the generation of timing pulses, first and second tacking execution signals, and data readout timing signals with respect to the vertical movement locus of the sewing needle in this embodiment. 10: Pattern designation device, 12: Start address memory, 14
: Pattern memory, 16: Data reading device, 24.42: AND circuit, 26, 28: Multiplexer, 30: Drive circuit, 32: Needle swing actuator, 34: Feed actuator, 40: Stop stitching determination circuit, 44: detection device,
46: Tack stitch data creation device, 48: Tack stitch execution control memory, 52: OR circuit, 54: Flip-flop, DP
l, DP2: First and second tacking execution signals, BSD:
Stitch data for securing stitches

Claims (1)

[Scope of Claims] 1. A pattern memory for storing stitch data corresponding to the stitches in each pattern in order to form many types of patterns, and for selecting a desired pattern from among the various types of patterns. a pattern selecting means; a data reading means for reading out stitch data regarding the pattern selected by the pattern selecting means from the pattern memory in synchronization with the up and down reciprocating movement of the sewing needle; and supplying the read stitch data. a sewing machine that is equipped with a driving means that controls the position of a stitch forming mechanism including a sewing needle in response to a sewing machine, a locking memory that stores control commands for executing locking stitches; detecting means for detecting that stitch formation has progressed to a predetermined stitch forming position and generating a tacking execution signal; a sewing machine comprising: control means for creating stitch data, and in response to generation of the locking stitch execution signal, interposing stitch data for locking stitches into stitch data from the pattern memory and supplying the stitch data to the driving means; Securing device. 2. The pattern selection means generates a discrimination signal indicating whether or not the selected pattern requires tacking in connection with the pattern selection, and the control means enables or disables the operation according to the discrimination signal. A tacking device for a sewing machine according to claim 1, characterized in that: 3. The control means is characterized in that, when the lock stitch execution signal is generated, the control means performs an operation of creating stitch data for one lock stitch in relation to each vertical reciprocating movement of the sewing needle. A tacking device for a sewing machine according to item 1.