JPS62213792A - Sewing machine equipped with tape feeder - 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 having a tape sewing function.

[Prior art]

Conventionally, sewing machines with tape stitching functions include those that control the tape feed at a predetermined ratio of the feed speed of the work cloth (Japanese Patent Laid-Open No. 175586/1986), and those that control the tape tension using a strain gauge. There is a known method (British Patent Publication No. GBA2152016) in which the tension of the tape is measured and the tension of the tape is controlled so that the measured value becomes equal to a set target value. In such a device, the speed ratio and tape tension to be controlled are set to predetermined numerical values by a switch. Then, during sewing, the operator operates a switch to change the speed ratio and tape tension.

[Problems to be solved by the invention]

Tape sewing machines utilize the elasticity of tape to
It is used to add gathers to products. The degree of gather required for a product is not always constant and may vary depending on the position even in one continuous sewing path. In this way, when creating different degrees of gathers depending on the sewing location, the operator must stop needle movement at a predetermined position, operate the switch mentioned above to change the state of tape elongation, and then continue sewing. was there. For this reason, the position at which the degree of gathering changes depends on the intuition of the operator, which impairs the uniformity of the product. Furthermore, since it is necessary to interrupt sewing and operate a switch, there is a problem in that work efficiency is poor. Furthermore, since the designer and the sewing worker are different people, and the gather pattern differs depending on the type of product, the worker must check the data for tape control every time the type of product to be sewn changes. There was the annoyance of having to do it.

[Purpose of the invention]

The present invention has been made to solve the above-mentioned problems, and its purpose is to enable sewing manufacturers to follow the sewing route for each product by simply specifying the type of sewing product. By automating tape stitching control, the aim is to equalize product quality and improve work efficiency.

[Means to solve the problem]

The structure of the invention for solving the above problems is as follows. That is, the present invention includes a sewing length detector that detects a value related to the length sewn by a sewing machine needle, and a device that variably applies tension to a tape that is supplied between a presser foot and a feed dog and is sewn onto a workpiece cloth. a detector for detecting a physical quantity related to the tension of the tape; and a detector for detecting a physical quantity related to the tension of the tape; a data input means for inputting control data from a storage medium storing a control target value related to the tension value and the tension of the tape; a processed product specifying means for inputting data regarding the type of processed product to be sewn; a control device that outputs a signal for controlling the state of the tape to the tension applying means so that the control target value and the measured value detected by the detector become equal; the control device includes: a data reading unit that selectively reads control data corresponding to the processed product designated by the processed product designation unit from the storage medium via the data input unit; and a data reading unit that inputs a signal from the sewing length detector to determine the current sewing pattern. Based on the control data read by the sewing position detection section that detects the section and the data reading section, the above-mentioned The present invention is characterized by comprising a tension control unit that sequentially controls the tension applying means so that the tape is in a specified state. In the above, the value related to tape tension refers to the tape tension and elongation rate, etc., and the physical quantity related to tape tension refers to the tension, elongation rate, etc. measured directly or indirectly. refers to the corresponding physical variable that is detected in order to Therefore, when the control device controls the state of the tape so that the measured value becomes the control target value,
The two variables being compared can be any variable that correlates with tape tension. In particular, the control data is given as the sewing length of the work cloth for each sewing section and the length of the tape to be sewn in that section (value in a non-stretched state), and from these values the tape length to realize the sewing is determined. The tension or elongation can be calculated and the actual tension or elongation can be controlled so that the tape reaches this value. In such a case, since the sewing length and tape length are input, data creation is easy and the finished dimensions of the product can be easily predicted. Furthermore, if the control data is given as a count, it is necessary to determine the feed pitch of the work cloth according to that data, but if it is given as a length, the feed pitch can be set freely.

[Effect]

When the processed product specifying means inputs data specifying the type of processed product, the data input means inputs control data corresponding to the product from the storage medium. The control data is given, for each section divided along each sewing path, as a value related to the sewing length and a value related to the length of the fabric to be sewn in that section. The control device determines the current sewing section based on the signal from the sewing length detector and, based on the control data, specifies the tape for each divided section until sewing of the specified sewing length is completed. M
(tension, elongation rate, etc.). By such action, the state of the tape is automatically changed with respect to the sewing position in accordance with the programmed control data. As a result, a predetermined amount of gathers can be automatically placed at a predetermined programmed position. Furthermore, if the type of product changes, the above processing is repeated by inputting data specifying the type of product using the processed product designation means. Therefore, even when tape sewing different types of products, it is not necessary to create different control data, and it can be easily handled.

【Example】

The present invention will be described below based on specific examples. FIG. 1 is a perspective view showing the overall configuration of a sewing machine equipped with the apparatus of this embodiment. An arm 3 is protruded from the sewing machine frame 1, and a needle 6 is attached to the table 2.
It is arranged so that it can move up and down. A support arm 4 is pivotally supported on the lower side of the arm 3, and a presser foot 5 is fixed to the tip of the support arm 4. The presser foot 5 controls the feed of the workpiece cloth 8 by acting together with a feed dog (path shown) disposed below. The motor fixing base 9 is fixed to the upper part of the sewing machine frame l, and a motor 20 is disposed thereon. The tension applying means mainly includes a motor 20, a driving roller 21, a driven roller 22, a tension lever 32, and a coil spring 33. Drive roller 21 is operatively coupled to motor 20 via a drive shaft 25 and gears. The driven roller 22 is in contact with the drive roller 21 and is supported by a bearing 23 so as to rotate in the opposite direction as the drive roller 21 rotates. The tension lever 32 is rotatably supported by a support member 34 provided on the arm 3. A coil spring 3 is attached to one end of the tension lever 32.
3 is engaged, which urges the tension lever 32 to rotate in the entry direction. The tape 7 is wound around a bobbin 12, which is supported by a support 11 fixed to a motor fixing base 9. The tape 7 is unwound from the bobbin 12, is sandwiched between the driven roller 22 and the driving roller 21, and is wound half a turn around each of them, descending along the front surface of the arm 3, and passing through the tension roller 31. and reaches the presser foot 5. Tension is applied to the tape 7 by a tension roller 31. The tension lever 32 stops at a position where it generates a rotating force that balances the tension of the tape 7. The more it rotates in the opposite direction, the greater the tension applied to the tape 7. The tape 7 is moved forward and backward as the drive roller 21 rotates forward and backward. An angle detector 40 consisting of a potentiometer is used to detect the rotation angle θ of the tension lever 32.
is provided, and its output signal is sent to an A/D converter 58.
It is input to the control device 50 via. Since the rotation angle θ of the tension lever 320 is proportional to the tension of the tape, the current tension of the tape 7 can be measured from this signal, and the motor 20 is rotated so that the tension lever 32 stops at the commanded angle. By controlling the rotation of , the desired tension can be obtained. FIG. 2 is a block diagram showing the electrical configuration of the tape feeding device according to the embodiment. The data input means consists of a floppy disk device 66 for inputting control data, and the processed product designation means consists of a keyboard 56. A CRT display 59 is also provided for monitoring data. The control device 50 is composed of a computer system, which includes a central processing unit (CP).
U) 51, a ROM 52 that stores a control program,
A RAM 53 that stores a proportional constant of the rotation angle of the tension lever 32 with respect to the elongation rate of the tape for each type of tape, and stores selectively input control data for one product, an input/output port 54, and a motor drive circuit. 55. The RAM 53 is backed up by a battery (not shown). The motor 20 is a pulse motor, and the motor drive circuit 55 is a pulse generator that receives rotation command pulses from the CPLI 51 and generates multiphase excitation pulses. Reference numeral 60 denotes a counting detector, which is composed of an encoder that detects the number of rotations of a main shaft that controls the vertical movement of the needle of the sewing machine, and a counter that counts its output signal. A sewing machine motor 64 is driven by the drive device 62. Next, the operation of the device of this embodiment will be explained based on a flowchart showing the processing procedure of the CPU 51. (a) Measuring the feed pitch of the work cloth After setting the feed pitch during sewing, test-sew a cloth of a certain length d, and calculate the number of stitches t from the increase in the output data of the stitch count detector at that time.
is detected, and the pitch P is calculated by dividing the length d by the number of stitches t,
It is stored in RAM53. (b) Measurement of elongation characteristics of the tape with respect to the rotation angle of the tension lever. First, as shown in FIG. 3, a signal is input from the angle detector 40, and the rotation angle θ of the tension lever 32 is determined to be the angle θ at which the tension applied to the tape 7 is zero. The motor 20 is controlled so that (200 to 208
). Here, the rotation angle θ is an angle taken in the direction from the vertical direction. Next, the drive roller 21 is rotated by a predetermined angle α, the tape is wound by Rα (a value converted to an elongation rate of 0, R is the radius of the roller), and the rotation angle β of the tension lever 320 at that time is detected as an angle. input from the device 40 (2
10-212). Next, the proportionality constant of the rotation angle θ to the elongation rate X of the tape is calculated using the following equation. However, f(θ) is the path length from the drive roller 21 to the presser foot 5 at the rotation angle θ. Once the proportionality constant is determined in this way, the relationship between the rotation angle θ and the elongation rate X can be determined using the following equation. θ=θ. -A-X...-(2
) (C) Input of control data The control data is stored together with the product number on the fluorobi disk for each type of processed product, as shown in FIG. The control data is given for each divided section, for each sewing path, as the sewing length of the section and the tape length corresponding thereto. In FIG. 4, the control data input program is shown from step 108 onwards. When the product number J is input from the keyboard 56 (108), the control data block of the corresponding product is input from the floppy disk to the RAM 53. When the input is complete, the
The number of stitches K(D) corresponding to the sewing length is obtained by dividing the sewing length D) of the second section of the sewing path by the feed pitch P.
116). Next, the elongation rate xs (D) is calculated from the tape length 1 (D) of the second section using the following formula. , i2(D) Furthermore, the control target angle θ, (D) of the tension lever 32 that can achieve the elongation rate is calculated by the following equation. θs (D)=θo A−Xs (D)
- (4) In this way, the control data for the entire sewing section is converted into the number of stitches and the control target angle. Thereafter, control data for other sewing paths are also converted in the same manner. These converted control data are stored in the RAM 53 in the relationship shown in FIG. (d) Sewing process In FIG. 5, a sewing route number is input from the keyboard 56 in order to specify the sewing of one product. The control data for the sewing path (pattern made in a) is sequentially stored in the RAM 5.
The data is transferred to the predetermined area of No. 3. Thereafter, the steps from step 306 onward are executed, and the sewing process for one product is executed. Here, C is the pattern number of the sewing route. W is a pointer indicating the start address of the RAM where the C-th pattern is stored. Next, the sewing process for each section is executed in step 310. As shown in FIG. 6, the tension lever 32 is set to the initial value θs (1) in step 400, and the tension lever 32 is set to the initial value θs (1).
When the SW key is pressed, steps 404 and subsequent steps are executed. After the stitch number counter NC inputting data from the stitch number detector 60 is reset and the section number is set to 1 (404 to 406), the sewing process of the second section starting from step 408 is executed. After the tension lever 32 is set to the control target angle θ, (D), when the drive pedal or motor start switch 565 of the sewing machine is turned on, a signal for driving the sewing machine motor 64 is output (408 to 4).
12). Next, the processes of steps 408 to 412 are executed until the count NC detected by the count detector 60 becomes equal to the commanded number of stitches K (D) in that section, and the tension lever 32 is controlled to the control target angle, Therefore, the elongation rate of the tape is controlled to the control target value, and sewing progresses. Next, when the sewing of the first section is completed, the vertical movement of the sewing machine needle is temporarily stopped, and it is determined whether the sewing of the entire section has been completed.If the sewing is not completed, the sewing process of the next section is executed. , the process returns to step 408 and the above processing is executed. In the above, the angle control of the tension lever is performed as follows. In FIG. 9, the output data of the angle detector 40 is input as θ (510). The measured value θ of the rotation angle is compared with the control target angle θ3 (D), and when the control target angle θs (D) is larger than the measured value θ by Δ, the actual tape elongation rate is too large compared to the target value. Therefore, the motor 20 is rotated forward by a predetermined amount, and the tape elongation rate is controlled to be small (512 to 514). On the other hand, when the measured value θ is larger than the control target angle θS (D) by Δ, the actual tape elongation rate is too small compared to the target value, so the motor 20 is reversed by a predetermined amount, and the tape elongation rate becomes large. (516-518). The above series of processes is repeatedly executed in real time, and eventually the rotation angle θ of the tension lever 32 is controlled within the range of ±Δ with respect to the control target angle θS(,D). As a result, the elongation rate of the tape is also controlled within a predetermined range with respect to the control target value XS. In this way, the tape is accurately controlled to the programmed target elongation rate both during sewing and when the sewing machine is stopped. Therefore, the tape can be sewn onto the workpiece cloth at the set elongation rate from the first stitch at a desired position. In this embodiment, since the sewing length and tape length are input as control data, there is an advantage that data can be easily created from the finished dimensions and the gather pattern. [Modification] Since the light transmittance of the tape changes depending on the elongation rate of the tape, the elongation rate of the tape can be directly measured by measuring the transmittance. Therefore, by comparing the measured value and the control target value, it is also possible to control the elongation state of the tape. Instead of the elongation rate of the tape, the tension of the tape may be given for each sewing section as the control data. In such a case, the measured value of tension from the angle detector and the control target value of tension are directly compared, regardless of the type of tape, and the tension of the tape is controlled by the same process as in the above embodiment. be exposed. In addition, when setting the elongation rate, in the above embodiment, the control target value was converted from the elongation rate to the rotation angle of the tension lever.
The measured value of the angle detector may be converted into an elongation rate using equation (2), and this value may be compared with the elongation rate of the control target value.

【Effect of the invention】

The present invention provides control data such as tape tension, elongation rate, etc. associated with the sewing position in a sewing machine having a tape stitching function that can control conditions such as tape tension and elongation rate.
The present invention is characterized in that the tape is selectively inputted from a stored medium for each type of product, and the tape is sewn onto the workpiece fabric while automatically controlling the state of the tape based on the control data. . Therefore, even if the degree of gathers changes partially, the entire product can be automatically and uniformly sewn, improving work efficiency. Furthermore, the sewing manufacturer does not need to create control data and only needs to specify the type of product to be processed, which improves the operability of the device.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a sewing machine having a tape feeding function according to a specific embodiment of the present invention, FIG. 2 is a block diagram showing the electrical configuration of the tape feeding function section, and FIG.
4, 5, and 6 are flowcharts showing the processing procedure of the computer system used in the sewing machine, and FIG. 7 is an explanatory diagram showing control data stored in the storage medium. , FIG. 8 is an explanatory diagram showing the structure of control data before and after conversion, and FIG. 9 is a flowchart showing the control procedure of the tension lever. 1.--Sewing machine frame 2.--Table 3.
・-・Arm 5-・・・Presser foot 7”・・・Tape 8・・Working cloth 12・・・・Bobbin 20・・・Motor 21・・・Drive roller 22-・1ill roller
32...Tension lever 31...Tension roller 40...Angle detector Fig. 5 Fig. 6

Claims (3)

[Claims] (1) A sewing length detector that detects a value related to the length sewn by a sewing machine needle, and a device that variably applies tension to the tape that is supplied between the presser foot and the feed dog and is sewn onto the workpiece fabric. a tension applying means; a detector for detecting a physical quantity related to the tension of the tape; a data input means for inputting control data from a storage medium storing a control target value related to the tension of the machine; a processed product specifying means for inputting data regarding the type of processed product to be sewn; a control device that outputs a signal for controlling the state of the tape to the tension applying means so that the measured value detected by the detector is equal to the measured value detected by the detector; a data reading section that selectively reads control data corresponding to a designated processed product from the storage medium via the data input means; and a sewing section that inputs a signal from the sewing length detector to detect the current sewing section. Based on the control data read by the position detection section and the data reading section, for each divided section of one sewing path,
A tape feeding device comprising: a tension control section that sequentially controls the tension applying means so that the tape is in a specified state until sewing of a specified sewing length is completed; sewing machine. (2) The storage medium stores values related to the tension, which are summarized for each type of processed product, and for each sewing path in one processed product, the elongation rate of the tape for each section taken on the sewing path. 2. A sewing machine equipped with a tape feed device according to claim 1, wherein control data is created for the tape feeding device. (3) The elongation rate of the tape created on the storage medium is
3. A sewing machine equipped with a tape feeding device according to claim 2, wherein each section is given a value related to the sewing length of the work cloth and a tape length corresponding thereto.