JPH0117397B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an electronic sewing machine that automatically forms a preselected desired pattern on a work cloth. The present invention relates to a technique for accurately forming a desired pattern without protruding from the area or being unevenly distributed within the area.

Prior Art In electronic sewing machines that automatically form a desired pattern selected from pre-stored patterns, the number of types of patterns that can be sewn has recently been expanded to, for example, more than 100 types. It is common for a figure to be displayed on the front of the sewing machine. However, because the display area on the front of the sewing machine for displaying the image of the pattern is limited, as the number of types of patterns that can be sewn increases, the size of the image of the pattern displayed on the front of the sewing machine becomes smaller than the actual size of the pattern. There is a tendency for the dimensions to be smaller than those of For this reason, with such conventional electronic sewing machines, it is difficult to predict the dimensions of the pattern that will actually be formed on the workpiece cloth from the shape displayed on the front of the sewing machine and set the sewing position, and it is difficult to set the sewing position. When forming a desired pattern within a sewing area on a workpiece cloth, there is a problem in that the pattern protrudes from the sewing area or is unevenly distributed within the sewing area.

On the other hand, by adjusting the pattern shape changing devices such as the needle amplitude adjuster and work cloth feed amount adjuster, and sewing the desired pattern on a trial basis before actual sewing, it is possible to make sure that the desired pattern fits accurately within the sewing area. It is conceivable to check whether the pattern is correct or not, but it would be extremely troublesome for the operator to carry out trial sewing every time a pattern is formed.

Purpose of the Invention The present invention has been made against the background of the above-mentioned circumstances, and its purpose is to provide a sewing area on a workpiece cloth on which a pattern is to be formed with a desired size of the same size as that of the sewing area. An object of the present invention is to provide an electronic sewing machine that can form a pattern.

Structure of the Invention In order to achieve the above object, the gist of the present invention is to control the relative position of a sewing needle and a work cloth in order to form each pattern in a cycle pattern having a predetermined standard size. In a sewing machine that is equipped with a stitch signal generator that generates a stitch signal and automatically stops the vertical and reciprocating movement of a sewing needle after completing the formation of a cycle pattern in accordance with the stitch signal, A designated operating body that can be operated manually to specify the size of the sewing area, and a reduction/enlargement ratio of the pattern is calculated based on the size of the sewing area designated by the designated operating body and the reference dimension, and and a signal changing circuit that changes the magnitude of the stitch signal according to the reduction/enlargement ratio.

Effects of the Invention With this method, when the size of the sewing area on the workpiece cloth in which a cycle pattern is to be formed is specified in accordance with the operation of the specified operating body, the signal changing circuit
The reduction/enlargement ratio is calculated based on the size of the sewing area and the reference dimension of the selected cycle pattern, and the size of the stitch signal generated from the stitch signal generator is adjusted according to the reduction/enlargement ratio. The size of the pattern is changed to match the size of the sewing pattern. Therefore, the size of the cycle pattern formed on the work cloth is automatically matched with the size of the sewing area, so it is completely eliminated that the cycle pattern protrudes from the sewing area or is unevenly distributed within the sewing area. It is.

Embodiment FIG. 1 shows the external appearance of an electronic sewing machine to which the present invention is applied, in which a pillar part 12 is erected on a bed part 10, and an arm part 14 is connected to the pillar part 14 at one end thereof. supported horizontally.
A head 16 is formed at the other end of the arm portion 14, and a sewing needle 18 is provided at the lower end of the head 16 and is driven reciprocally in the vertical direction in synchronization with the rotation of the main shaft of the sewing machine (not shown). A bar 20 and a presser foot 22 which can be manually moved to a raised position and a lowered position are provided. On the other hand, the bed section 10
A feed dog 24 is provided near the needle drop point of the upper sewing needle 18 to feed the workpiece cloth by being reciprocally driven in synchronization with the rotation of the main shaft of the sewing machine.

Pattern display section 2 provided on the front side of the arm section 14
6, a large number of patterns (approximately 100 types) consisting of groups A, B, and C are displayed together with two-digit pattern numbers (not shown). Those belonging to Group B are so-called continuous sewing patterns, including practical stitches such as straight stitches and zigzag stitches, and decorative patterns. Those belonging to Group A are letters such as alpha alphabets and numbers, and the patterns belonging to Group C are series of patterns or patterns. It is a character. The patterns belonging to groups A and C are so-called cycle patterns in which each pattern is sewn individually.
Ten pattern selection switches 28 each having a fixed number are arranged below the pattern display section 26 to select a desired pattern. The pattern selection switch 28 also serves as a designation operating body for inputting the size of the sewing area of a desired pattern. Also,
On the right side of the pattern display section 26, there is a two-digit numerical display 30 for displaying the pattern number or the size of the sewing area in which the pattern is to be formed, and a 1-cycle designation switch 32 for designating single-cycle sewing. and a display changeover switch 34 for switching the number displayed on the number display 30 from the pattern number to the size of the sewing area, and an LED 36 for displaying each operation.
38. A combination designation switch 39 for designating a combination of cycle patterns is provided between the pattern selection switch 28 and the display changeover switch 34. Note that 40 is a start/stop switch for starting and stopping the sewing machine, and 42 is a speed setting device for setting the speed of the sewing machine motor 44 to a desired value.

The electronic sewing machine configured as described above is equipped with a control circuit shown in FIG. 2. That is, when a two-digit pattern number corresponding to a desired pattern is input to the encoder 46 according to the operation of the pattern selection switch 28, it is converted into a code signal representing the input numerical value at the encoder 46, and the code signal is Through the gate 48, the first address memory 50,
Pattern data SM to input port L of pattern discriminator 52, stitch number data memory 54, and multiplexer 56
Supplied as. The gate 48 switches the supply destination of the output signal of the encoder 46 when a display switching signal DC, which will be described later, is generated. This is a case in which the pattern selection switch 28 is used as an input key for inputting the dimensions of the sewing area on the workpiece cloth on which the cycle pattern is to be sewn, and the signal representing the dimensions of the sewing area, which is the output signal of the encoder 46, is 48 to the reduction/enlargement ratio calculation circuit 58 and the input port H of the multiplexer 56 as sewing length data SL. The encoder 46 is designed to generate the operation signal SO when a two-digit value is input from the pattern selection switch 28, and the operation signal SO is supplied to the load input terminals of the adders 60 and 62. be done.

The start address memory 50 stores a large number of start addresses corresponding to each pattern, and supplies the start address corresponding to the input pattern data SM to the channel selector 64. The channel selector 64 operates in a state in which a start signal SST is not generated from the motor control circuit 66, which will be described later.
The start address from the start address memory 50 is sent to the pattern code memory 6 via the channel selector 64.
8, but the activation signal SST
is generated, the start address output from the pattern code memory 68 is allowed to pass through the channel selector 64 to the stitch data generator 70.

A timing signal TS synchronized with the rotation of a sewing machine main shaft (not shown) is supplied to the stitch data generator 70 from a timing signal generator 72, and in order to form a pattern corresponding to the pattern data SM in synchronization with the timing signal TS. A series of stitch signals are sequentially supplied to the actuator drive circuit 74. That is, the stitch data generating device 70 has an address counter that is loaded with a leading address and counts a timing signal TS in addition to the loaded contents, and many types of stitch signals are stored in advance in the stitch data generator 70. It is equipped with a stitch data memory, etc., which sequentially outputs stitch signals addressed according to the count contents. The stitch signals each include a needle position signal SH representing the swinging position of the sewing needle 18 and a feed signal SF representing the feed amount and feed direction of the workpiece cloth,
The needle position signal SH is directly supplied to the actuator drive circuit 74, and the sending signal SF is supplied to the actuator drive circuit 74 via the data change circuit 80. Note that the stitch data generation device 70 includes:
When a series of stitch signals generated therefrom reaches its terminal end, an end signal SE is generated, and the end signal SE is supplied to an AND circuit 82.

The actuator drive circuit 74 receives a needle position signal.
The needle swing actuator 76 converts SH and feed signal SF into analog signals and amplifies the power.
and feed actuator 78, respectively. The needle swing actuator 76 changes the swing position of the needle bar 20 by driving the needle swing mechanism, and the feed actuator 78 changes the feed by positioning the rotational position of a feed adjuster (not shown). The amount and direction of feed of the work cloth by the teeth 24 are changed.

In the data change circuit 80, a coefficient signal representing the reduction/enlargement ratio is sent from the reduction/enlargement ratio calculating circuit 58.
SK is supplied, and the magnitude of the feed signal SF is changed and corrected by multiplying the magnitude represented by the feed signal SF by the reduction/enlargement ratio represented by the coefficient signal SK.
The corrected sending signal SF is supplied to the actuator drive circuit 74.

In the pattern discriminator 52, the pattern data
It is determined whether the pattern corresponding to SM belongs to the cycle pattern (single sewing pattern) of group A or C, or to the continuous sewing pattern of group B, and if it belongs to the cycle pattern, an H level signal is output. The signal is supplied to an AND circuit 84. An H level signal is supplied to the AND circuit 84 in response to the pressing operation of the combination designation switch 39, and a signal indicating that a combination has been designated following the selection of a cycle pattern is supplied to the AND circuit 84. The signal is supplied from 84 to address counter 86 via OR circuit 82, and is also supplied to adders 60 and 62 as addition command signal SA. The address counter 86 is configured such that a clear signal consisting of a pulse with a fixed time width is supplied from the one-shot multi-circuit 88 after the generation of the activation signal SST, and the count contents of the address counter 86 are brought to zero by the clear signal. It is starting to be cleared. Further, the count contents of the address counter 86 are supplied to the pattern code memory 68 as a signal specifying the temporary storage location or the readout location of the stored top address.

The pattern code memory 68 receives the activation signal SST.
If not supplied, it enters a reading state, and the start address supplied from the start address memory 50 via the channel selector 64 is temporarily stored in a location specified by the count contents of the address counter 86, while a start signal SST is generated. If so, it enters a reading state and outputs the leading address of the location specified by the count contents of the address counter 86 to the stitch data generator 70 via the channel selector 64.

The number of stitches of each cycle pattern is stored in the stitch number data memory 54, and a signal representing the number of stitches corresponding to the pattern data SM is sent to an adder 60.
supply to. In response to the operation signal SO, the adder 60 loads a signal representing the number of stitches output from the stitch number data memory 54, and when a cycle pattern is selected and the combination designation switch 39
The loaded signals are added according to the addition command signal SA generated when the pressing operation is performed.
Then, the adder 60 supplies the motor control circuit 66 with a stitch number signal SN representing the total value of the added results.

In the motor control circuit 66, for example, a start signal is generated in accordance with a pressing operation of the start/stop switch 40.
The number of stitches represented by the number of stitches signal SN is loaded in a state in which a T-type flip-flop circuit that alternately generates and eliminates SST and a 1-cycle designation signal SI indicating that the 1-cycle designation switch 32 has been operated are supplied. A subtraction counter is provided which is subtracted in response to the timing signal TS and which resets the T-type flip-flop circuit when the loaded content decreases to zero. When the count content of the subtraction counter is reduced to a predetermined constant value, a shift command signal STO is supplied to the motor drive circuit 92, and then, when the count content reaches zero and the hand position detector From 94, a rising position signal indicating that the needle position is in the rising position
When SU is supplied, the start signal SST that has been supplied to the motor drive circuit 92 is stopped.

In the motor drive circuit 92, the start signal
While SST is being supplied, the sewing machine motor 44 is operated so that the signal representing the actual speed of the sewing machine motor 44 supplied from the speed detector 96 and the signal representing the command speed supplied from the speed setting device 42 match.
Electric power is supplied to the sewing machine motor 44, and the speed of the sewing machine motor 44 is controlled to the speed set by the speed setting device 42. Further, while the speed change command signal STO is being supplied in addition to the start signal SST, electric power for driving the sewing machine motor 44 at a predetermined low rotational speed is output, and the sewing machine motor 44 is driven at a low speed. On the other hand, when the supply of the start signal SST is stopped, the power supply to the sewing machine motor 44 is stopped. Therefore, when a pattern belonging to the cycle pattern is selected by the pattern selection switch 28, the sewing machine motor 44 is activated at a certain period before the completion of sewing the cycle pattern.
is driven at a low speed, and when the sewing needle 18 reaches the raised position upon completion of sewing the cycle pattern, the sewing machine motor 44 is automatically stopped. Here, the output signal of the 1-cycle designation switch 32 is supplied to a T-type flip-flop circuit 98, and each time the 1-cycle designation switch 32 is pressed, the T-type flip-flop circuit 98 is reset or set. The one-cycle designation signal SI at the H level supplied from the flip-flop circuit 98 to the motor control circuit 66 and the AND circuit 100 is generated and extinguished for each pressing operation. Further, the output signal of the display changeover switch 34 is also supplied to another T-type flip-flop circuit 102.
A signal supplied from the T-type flip-flop circuit 102 to the AND circuit 100 is generated and extinguished each time the display changeover switch 34 (H level) is pressed. Therefore, AND circuit 10
The display switching signal DC (H level) supplied from 0 to the gate 48 and the multiplexer 56 is one cycle
In other words, it is a switching operation that indicates that the individual sewing of a cycle pattern (discontinuous sewing) is specified and that the dimensions of the area where the pattern is planned to be formed on the workpiece cloth are input and displayed on the numerical display 30. It represents that something has been done.

The multiplexer 56 always selects its input port L and therefore allows the pattern data SM to be supplied to the display drive circuit 104 via the multiplexer 56, but when the display switching signal DC is supplied, it selects its input port H. By selecting
Sewing length data SL indicating the length of the sewing area where a pattern is to be formed on the work cloth is sent to the multiplexer 56.
The signal is allowed to be supplied to the display drive circuit 104 via the. The display drive circuit 104 supplies a display signal to the numeric display 30 so that the numerical value represented by the supplied signal is optically displayed on the numeric display 30.

The operation of this embodiment will be explained below.

When sewing one of the continuous sewing patterns belonging to the group B, the pattern number of the continuous sewing pattern is input by operating the pattern selection switch 28, and the 1 cycle designation switch 32 and the display changeover switch 34 are operated. are not operated together. Therefore, since the display switching signal DC cannot be generated, the output signal of the encoder 46 is
8 is supplied as pattern data SM to the start address memory 50, multiplexer 56, etc.
In the multiplexer 56, its input port L
is selected, the pattern data SM is supplied to the display drive circuit 104 through the multiplexer 56, and the pattern number of the selected continuous sewing pattern is displayed on the numerical display 30. At this time, the 1 cycle designation switch 32 and the display changeover switch 34
Even if the input port H of the multiplexer 56 is selected by erroneously operating the display switching signal DC, the sewing length data SL is not output from the gate 48, so the numeric display 30
nothing is displayed. Furthermore, since the pattern data SM supplied to the pattern discriminator 52 corresponds to a continuous sewing pattern, no signal is output from the pattern discriminator 52, and even if the combination designation switch 39 is operated, the No signal is output from circuit 84. Therefore, a count signal is not supplied to the address counter 86, and the temporary storage location or readout location of the leading address in the pattern code memory 68 is always designated at a constant address, for example, address zero. The start address memory 50 outputs the start address corresponding to the pattern data SM supplied thereto.
Since the activation signal SST is not supplied to the channel selector 64, the first address from the first address memory 50 is supplied to the pattern code memory 68 via the channel selector 64 and temporarily stored at address zero. Since the activation signal SST is not supplied to the pattern code memory 68 either, the pattern code memory 68 is in the reading state.

When the start/stop switch 40 is pressed in the above state, the start signal SST is supplied from the motor control circuit 66 to the motor drive circuit 92.
The sewing machine motor 44 is driven at a speed set by the speed setting device 42.
The driving continues until the start/stop switch 40 is pressed again. At this time, the activation signal is also sent to the channel selector 64 and pattern code memory.
Since SST is supplied, the pattern code memory 68
is in the read state, and the start address already stored at the zero address is transferred from the pattern code memory 68 via the channel selector 64 to the stitch data generator 70.
is supplied to For this reason, the stitch data generator 7
Needle position signal synchronized with timing signal TS from 0
Since the stitch signal consisting of SH and the feed signal SF is sequentially supplied to the actuator drive circuit 74, a continuous sewing pattern is continuously formed on the work cloth. At this time, since the sewing length data SL is not outputted from the gate 48, the reduction/enlargement ratio calculating circuit 58 supplies the coefficient signal SK whose content is set to 1 to the data changing circuit 80. Therefore, since the 1-cycle designation signal SI is supplied to the reduction/enlargement ratio calculation circuit 58, the content of the count signal SK supplied to the data change circuit 80 is set to 1, and the stitch data generator Sending signal SF supplied from 70 to actuator drive circuit 74
The size of is not changed.

Next, when forming one of the cycle patterns belonging to the pattern group A or C, the pattern number of the cycle pattern is input according to the operation of the pattern selection switch 28, while the one cycle designation switch 32 is input. In accordance with the operation, the T-type flip-flop circuit 98 is set, thereby supplying the 1-cycle designation signal SI to the motor control circuit 66 and causing the LED 36 to light up. At this time, the pattern discriminator 52 discriminates the cycle pattern and supplies an output signal to the AND circuit 84, but when one cycle pattern is formed, the combination designation switch 3 for combining the cycle patterns is activated.
9 is not operated, the address counter 86 is not supplied with a signal for counting in the same way as in the operation described above. Therefore, the start address memory 50
From then on, the start address for forming the cycle pattern corresponding to the pattern data SM is temporarily stored at address zero of the pattern code memory 68 via the channel selector 64.

On the other hand, in the stitch number data memory 54, a signal representing the number of stitches of the pattern corresponding to the pattern data SM is supplied to an adder 60, and the adder 60 supplies a signal representing the number of stitches in accordance with the operation signal SO. is loaded, and the stitch number signal SN representing the number of stitches of one selected cycle pattern, which is the loaded content from the adder 60, is sent to the motor control circuit 6.
6. In addition, unit length data memory 5
5, a signal representing the unit length (reference length) of the pattern corresponding to the pattern data SM is supplied to the adder 62, where it is loaded in accordance with the operation signal SO. Then, a signal representing the unit length of one selected cycle pattern, which is the content loaded from the adder 62, is supplied to the reduction/enlargement ratio calculation circuit 58.

At this time, when the display changeover switch 34 is first pressed in order to designate the size of the sewing area in which the desired one selected cycle pattern is to be formed, the T-type flip-flop circuit 102 is set and the T-type flip-flop circuit 102 is set. Since the flip-flop circuit 102 supplies an H level signal to the AND circuit 100 and the LED 38, a display switching signal DC is generated. For this reason, gate 48 is switched,
In addition, the input port H of the multiplexer 56 is selected, and the LED 38 is turned on.

Next, when the pattern selection switch 28 is operated as a numerical input key for inputting the size of the sewing area, a signal representing the size of the sewing area generated from the encoder 46 is passed through the gate 48 to the sewing length data. Reduction/enlargement ratio calculation circuit 58 as SL
and is supplied to multiplexer 56. Therefore, in the reduction/enlargement ratio calculation circuit 58, the ratio between the unit length of the desired cycle pattern supplied from the adder 62 and the size of the inputted sewing area (length of the sewing area in the work cloth feeding direction ÷ cycle A reduction/enlargement ratio (correction coefficient) is calculated by taking the length of the pattern in the work cloth feeding direction, and a coefficient signal SK representing the reduction/enlargement ratio is sent to the data change circuit 80.
is supplied to Further, since the input port H of the multiplexer 56 is selected, the sewing length data SL is supplied to the display drive circuit 104 through the multiplexer 56, and the sewing length data SL is supplied to the display drive circuit 104 through the multiplexer 56, and the sewing length data SL is displayed in the input sewing area in the work cloth feeding direction. The length dimension is displayed.

When the start/stop switch 40 is pressed in the above state, the start signal SST is supplied from the motor control circuit 66 to the motor drive circuit 92.
A selected desired cycle pattern is formed on the work cloth according to the same operation as described above, but the length dimension of the cycle pattern formed on the work cloth in the work cloth feeding direction is already displayed. It is formed to match the length dimension of the sewn area. That is, the stitch data generation device 70
The series of stitch signals generated from the data changing circuit is determined so that the size of the selected cycle pattern on the work cloth becomes a predetermined size (reference length in the work cloth feeding direction). 80
is supplied with a coefficient signal SK representing a reduction/enlargement ratio, which is the ratio between the reference length of the selected cycle pattern and the length of the sewing area allowed to be sewn on the work cloth, from the reduction/enlargement ratio calculation circuit 58; In addition, in the data changing circuit 80, the reduction/enlargement ratio represented by the coefficient signal SK is multiplied by the sending signal SF generated from the stitch data generating device 70, thereby changing the sending signal.
The magnitude of SF is corrected, and the corrected sending signal SF is supplied to the actuator drive circuit 74. For example, if the unit length (reference length) of the selected desired cycle pattern is 20 mm and the allowable sewing area on the work cloth is 16 mm, the data change circuit 80 has a reduction/enlargement ratio. 0.8
Since a coefficient signal SK representing
4. As a result, the length of the desired cycle pattern formed on the work cloth can be made to accurately match the length of the sewing area inputted in advance.

Furthermore, even when a plurality of desired cycle patterns are combined, the length of the combined cycle patterns in the work cloth feeding direction is made to match the length of the sewing area on the work cloth where pattern formation is permitted. That is, when the pattern number of the desired first cycle pattern is input by operating the pattern selection switch 28 while the 1 cycle designation switch 32 and the display changeover switch 34 are pressed, the same operation as described above occurs. Then, the start address corresponding to the first cycle pattern is temporarily stored at address zero of the pattern code memory 68. Next, when the combination designation switch 39 is pressed, a signal is supplied from the AND circuit 84 through the OR circuit 82 to the address counter 86, and the address counter 86 counts the signal. Therefore, 1 is added to the contents of the address counter 86, so that the signal representing the contents of the address counter 86 changes the temporary storage location in the pattern code memory 68 to address 1. When the pattern number of the second desired cycle pattern is input according to the operation of the pattern selection switch 28, the start address corresponding to the second cycle pattern is set to 1 of the pattern code memory 68.
The address is temporarily stored. By repeating such operations, a desired number of cycle patterns can be combined. At this time, the number of stitches and the unit length are sequentially added in the adders 60 and 62 according to the addition command signal SA output from the AND circuit 84, so that the motor control circuit 66 receives the combined cycle pattern. A stitch number signal SN representing the total number of stitches is supplied. Next, while the 1 cycle designation switch 32 and the display changeover switch 34 are pressed and the display changeover signal DC is generated, the size of the sewing area on the workpiece cloth (dimension in the workpiece cloth feeding direction) is adjusted to select the pattern. The input is made according to the operation of the switch 28. The dimensions of the sewing area are those in which the selected cycle pattern combination is to be formed. The sewing length data SL representing the size of the sewing area is supplied from the gate 48 to the reduction/enlargement ratio calculation circuit 58 in the same manner as in the above-described operation.
The signal is supplied to the display drive circuit 104 via the multiplexer 56. As a result, the reduction/enlargement ratio calculation circuit 58
In , the reduction/enlargement ratio can be calculated by taking the ratio between the total reference length of the selected cycle pattern and the size of the sewing area, and the coefficient signal SK representing the reduction/enlargement ratio is changed as data. While being supplied to the circuit 80, the size of the sewing area is displayed on the numerical display 30.

In the above state, when the start/stop switch 40 is pressed, the motor control circuit 66 generates a start signal SST to start rotating the sewing machine motor 44.
Since the occurrence of SST, a clear signal with a predetermined pulse width is supplied from the one shot multi circuit 88 to the address counter 86 as a clear signal, so that the contents of the address counter 86 are cleared to zero. For this reason, the first address temporarily stored in advance at address zero of the pattern code memory 68 is the first address stored in the channel selector 64.
Since the stitch data is supplied to the stitch data generating device 70 through the process, a first cycle pattern is first formed on the work cloth. When the series of stitch signals generated to form this first cycle pattern reaches its end, the stitch data generator 70 sends an end signal.
SE passes through the OR circuit 82 to the address counter 86
Since the address counter 86 counts the signal, the pattern code memory 68
Change the reading location to address 1. Therefore, the start address for forming the second cycle pattern is supplied from the pattern code memory 68 to the stitch data generator 70 via the channel selector 64, so that the second cycle pattern can be created following the first cycle pattern. A cycle pattern is formed on the processed fabric. In the above pattern forming process, a sending signal is supplied from the stitch data generating device 70 to the actuator drive circuit 74.
Since the size of SF is corrected in the data change circuit 80 according to the same operation as described above, the total length of all the cycle patterns formed on the work cloth is inputted in advance at the time of completion of sewing the combined cycle patterns. This makes it possible to match the length of the sewing area. Furthermore, when the sewing of the combined cycle pattern is completed, the stitch number signal indicating the total number of stitches is
In accordance with SN, the sewing machine motor is automatically stopped in the same manner as described above.

As described above, according to this embodiment, when a desired cycle pattern is selected by the pattern selection switch 28, after the 1-cycle designation switch 32 is pressed, the sewing area in which the cycle pattern is allowed to be formed is selected. By specifying and inputting the size, a cycle pattern of the same size as the sewing area is formed on the work cloth. Therefore, if the sewing start position is set at the edge of the sewing area, a cycle pattern of the same size as the sewing area is automatically formed within that sewing area, so the cycle pattern may protrude from the sewing area or This completely eliminates the problem of being unevenly distributed within the world. Furthermore, the same effect can be obtained even when one cycle pattern is selected or when a plurality of cycle patterns are selected.

Although the embodiment of the present invention has been described above based on the drawings, the present invention can also be applied to other aspects.

For example, in the block diagram of FIG. 2, part or all of the circuit surrounded by a dashed line can be constructed by a so-called microcomputer. Furthermore, in the above embodiment, the sending signal SF
Reduction/enlargement ratio calculation circuit 5 to change the size of
8. A signal change circuit consisting of a data change circuit 80 and the like is provided, but it may also be provided to change the magnitude of the needle position signal SH, and also if the sewing machine In a sewing machine in which the work cloth holder is relatively moved, such a signal changing circuit may be provided to change the magnitude of the signal representing the amount of relative movement.

In addition, in the above embodiment, in order to match the size of the cycle pattern formed on the workpiece cloth with the sewing area, the size of the feed signal SF is multiplied by the reduction/enlargement ratio. For example, a series of stitch data to form a cycle pattern is combined with character data to form a character and space data to determine the space between characters. In this case, the cycle pattern formed on the work cloth may be made to match the sewing area by changing only the space data. In such a case, there is an advantage that the shape of the character is not changed.

The above-mentioned embodiment is merely one embodiment of the present invention, and various modifications may be made to the present invention without departing from the spirit thereof.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the appearance of a sewing machine to which an embodiment of the present invention is applied. FIG. 2 is a block diagram showing the circuit configuration of the embodiment of FIG. 1. 18... Sewing needle, 28... Pattern selection switch (designated operating object), {58... Reduction/enlargement ratio calculation circuit, 80
...data change circuit} (signal change circuit), 70...
Stitch data generator (stitch signal generator).

Claims (1)

[Scope of Claims] 1. A stitch signal generating device that controls the relative position of a sewing needle and a workpiece cloth in order to form each stitch in a cycle pattern having a predetermined reference dimension; A sewing machine that automatically stops the vertical and reciprocating movement of a sewing needle after the completion of forming a cycle pattern according to the present invention includes a designating operation body that can be manually operated to specify the size of a sewing area on a workpiece cloth in which the cycle pattern is formed. , a signal changing circuit that calculates a reduction/enlargement ratio of the pattern based on the size of the sewing area designated by the specified operating body and the reference dimension, and changes the size of the stitch signal according to the reduction/enlargement ratio; and electronic sewing machines.